Should My Teen Get the HPV Vaccine? A Doctor’s Guide

As a parent, you want to give your child the best possible start in life, and that includes protecting their long-term health. One important step is the human papillomavirus (HPV) vaccine, which protects against the virus. HPV is extremely common and is linked to several cancers and conditions that can affect both men and women.

The good news is that HPV-related diseases are largely preventable with vaccination. For many parents in Singapore, the question is not just whether the vaccine is necessary, but also when their teen should receive it, how safe it is, and what to expect.

This guide will walk you through everything you need to know about the HPV vaccine, based on current recommendations and clinical evidence.

What is HPV and Why is it a Concern?

HPV, or human papillomavirus, is one of the most prevalent viral infections worldwide. It is estimated that more than half [1] of sexually active people will be exposed to HPV at some point in their lives. The virus spreads primarily through skin-to-skin and sexual contact, and because it is so common, most people who contract HPV may not even realise it.

The body’s immune system often clears the infection naturally within a year or two. However, some HPV strains are more persistent [2]. When these high-risk types remain in the body, they can cause changes in cells that may develop into cancer years or even decades later.

The high-risk HPV strains are strongly associated with several cancers, including:

• Cervical cancer in women, where almost all cases [3] are linked to HPV infection
• Anal, penile, and throat cancers in both [4] men and women
• Oropharyngeal cancers [5] (back of the throat, tonsils, base of the tongue) are increasing [6] in incidence worldwide

Meanwhile, low-risk strains of HPV, although not cancer-causing, are responsible for genital warts [7], a common and distressing condition that can affect self-esteem and relationships.

In Singapore, cervical cancer continues to be a significant concern [8], ranking among the top 10 cancers in women. According to local statistics, hundreds of women are diagnosed every year, with many cases detected in their 30s to 50s. This is an age range when women are often balancing careers, families, and personal commitments.

What is important to remember is that HPV-related diseases are largely preventable. By vaccinating your teens before they are exposed to the virus, you are providing them with a powerful layer of protection against cancer and other HPV-related conditions later in life.

How Does the HPV Vaccine Work?

The HPV vaccine is designed to teach the body’s immune system how to recognise and fight HPV before an actual infection occurs. It contains virus-like particles (VLPs) that resemble the outer shell of the human papillomavirus but contain no genetic material. This means the vaccine cannot cause HPV infection.

Once the vaccine is given, the immune system responds by producing antibodies that remain in the body for years. If your teens are later exposed to HPV, these antibodies act like a protective shield, neutralising the virus before it can cause any damage.

This pre-emptive protection is why vaccination works best before HPV exposure, ideally during the teenage years.

Gardasil-4 vs Gardasil-9: What is the Difference?

Parents may come across two versions of the HPV vaccine: Gardasil-4 and Gardasil-9. It can be confusing to know which one is more suitable for their teens. Both vaccines are designed to protect against the most dangerous strains of HPV, but the difference lies in the breadth of coverage.

• Gardasil-4 was the earlier version and protects against four HPV types:

• HPV 16 and 18 – these are high-risk strains responsible for about 70% of cervical cancers [9] worldwide. They are also linked to other cancers, including anal, penile, and throat cancers.
• HPV 6 and 11 – these are low-risk strains that do not cause cancer but are responsible for about 90% of genital warts [10]. While not life-threatening, genital warts can be distressing, difficult to treat, and may recur.
• Gardasil-9 builds on this protection by covering the same four strains as Gardasil-4 plus five additional high-risk strains: 31, 33, 45, 52, and 58. These added strains are significant because they account for an additional 20% of cervical cancers globally [11]. By including them, Gardasil-9 protects against about 90% of all cervical cancers, as well as other HPV-related cancers in both men and women.

This broader coverage is why Gardasil-9 is now the standard vaccine in Singapore. It offers families greater reassurance that their teens are receiving more comprehensive protection available today.

At What Age Should My Teen Get the HPV Vaccine?

Timing is crucial for HPV vaccination. Both the World Health Organization (WHO) and the Ministry of Health (MOH) in Singapore recommend vaccination during adolescence, ideally before the onset of sexual activity.

Generally, the time frame is as follows:

• The optimal age is 9 to 14 years old, when the immune system produces a stronger and more effective response to the vaccine.
• Both girls and boys should receive the HPV vaccine. HPV does not only affect women. It can cause cancers of the throat, anus, and penis in men as well. Vaccinating boys also helps reduce HPV circulation in the community.
• For those who missed vaccination in early adolescence, a catch-up programme is available up to age 26 years old, ensuring young adults can still benefit from protection.

Is the HPV Vaccine Safe for Teenagers?

When it comes to any vaccine, safety is often the first question on a parent’s mind. The HPV vaccine has one of the most extensively studied safety records among modern vaccines. Since its introduction more than 15 years ago, over 500 million doses have been administered worldwide. Data from numerous large-scale studies, as well as continuous monitoring by global health authorities, show that the vaccine is both safe and effective.

Common, short-term side effects

Like many other routine vaccines, the HPV vaccine may cause mild and temporary side effects. These include:

• A low-grade fever
• Headache, tiredness, or mild muscle aches
• Soreness, redness, or swelling at the injection site

These reactions are usually short-lived, lasting a day or two, and indicate that the immune system is responding to the vaccine.

Rare, serious side effects

Serious side effects are extremely rare. Ongoing global safety monitoring has found no consistent evidence [12] linking the HPV vaccine to long-term complications. The vaccine’s safety record is comparable to other widely used childhood and adolescent vaccines.

Myths and misconceptions

Misinformation online has led some parents to worry about issues such as infertility, autoimmune conditions, or chronic illnesses. Extensive scientific research has confirmed that the HPV vaccine does not cause infertility or affect long-term health. Multiple studies conducted across different populations and age groups have consistently reached the same conclusion, which is that the HPV vaccine is safe.

Local reassurance in Singapore

In Singapore, all vaccines, including Gardasil 9, are strictly regulated by the Health Sciences Authority (HSA). The HSA continuously monitors vaccine safety and effectiveness, giving parents the added assurance that their teen is receiving a trusted and thoroughly vetted vaccine.

How Many Doses for HPV Are Needed and What’s the Schedule?

The number of doses required depends on your child’s age at the time of vaccination. This is because younger immune systems tend to respond more efficiently, meaning fewer doses are needed for lasting protection.

The timeline generally looks like:

• Ages 9 to 14 years – only 2 doses are needed. The second dose is given 6 to 12 months after the first.
• Ages 15 to 26 years – a 3-dose schedule is recommended. The doses are spaced at 0, 2, and 6 months.

If your teens miss a scheduled dose, there is no need to restart the entire course. Our doctor will adjust the timing to ensure the series is completed. What matters most is that your teens receive the full set of doses, as this ensures protection against HPV.

Is the HPV Vaccine Subsidised in Singapore?

The HPV vaccine is part of Singapore’s broader strategy to prevent cancer and protect population health. To make it more accessible for families, several subsidy schemes are in place:

• School-Based HPV Vaccination Programme – secondary girls are eligible to receive the HPV vaccine at no cost, administered directly in school as part of the national health initiative.
• CHAS and MediSave – Singapore Citizens can use CHAS subsidies and claim up to SGD500 yearly from MediSave per account to offset the cost of HPV vaccination at approved clinics. This makes vaccination more affordable for families of different income levels.
• Public and private clinics – HPV vaccination is widely available. While public clinics typically follow national subsidy schemes, private clinics may also offer packages for the full vaccination series.

What Should I Expect During My Teen’s HPV Vaccination Appointment?

For many parents and teens, knowing what to expect can help reduce any nervousness about vaccination. The process is simple, efficient, and usually completed within half an hour.

It entails:

• Pre-vaccination check – our doctor will review your teen’s health history, allergies, and suitability for the vaccine. This step ensures that your child is medically fit for vaccination.
• Injection – the vaccine is given as a quick injection in the upper arm. The procedure is similar to other routine vaccinations and is usually well-tolerated.
• Observation period – after the injection, your teen will remain in the clinic for about 15 minutes. This is standard practice to ensure there are no immediate side effects.
• Post-care – mild arm soreness or a temporary fever may occur, but typically resolves quickly. Most teens can return to school, sports, or their usual activities straight after the appointment.

Our clinic will also schedule reminders for the next dose, helping your teen stay on track to complete the full vaccination series.

Give Your Teen a Head Start on Health

The HPV vaccine is a safe and effective tool in preventing HPV-related cancers and diseases. By choosing to vaccinate your teens, you are investing in their long-term health and protecting them from conditions that may only surface decades later.

At Ardennes, we understand that parents want clear answers and reliable guidance when it comes to their child’s health. Our doctors are here to provide professional advice, address your concerns, and ensure your teens receive the best care.

Book an HPV vaccine appointment with Ardennes today and give your teen the protection they deserve.

References

1. Ault K. A. (2006). Epidemiology and natural history of human papillomavirus infections in the female genital tract. Infectious diseases in obstetrics and gynecology, 2006 Suppl, 40470. https://doi.org/10.1155/IDOG/2006/40470
   
2. So, K. A., Lee, I. H., Lee, K. H., Hong, S. R., Kim, Y. J., Seo, H. H., & Kim, T. J. (2019). Human papillomavirus genotype-specific risk in cervical carcinogenesis. Journal of gynecologic oncology, 30(4), e52. https://doi.org/10.3802/jgo.2019.30.e52
   
3. Cervical Cancer Causes, Risk Factors, and Prevention – NCI. (2022). In www.cancer.gov. https://www.cancer.gov/types/cervical/causes-risk-prevention
   
4. Baba, S. K., Alblooshi, S. S. E., Yaqoob, R., Behl, S., Al Saleem, M., Rakha, E. A., Malik, F., Singh, M., Macha, M. A., Akhtar, M. K., Houry, W. A., Bhat, A. A., Al Menhali, A., Zheng, Z. M., & Mirza, S. (2025). Human papilloma virus (HPV) mediated cancers: an insightful update. Journal of translational medicine, 23(1), 483. https://doi.org/10.1186/s12967-025-06470-x
   
5. Sabatini, M. E., & Chiocca, S. (2020). Human papillomavirus as a driver of head and neck cancers. British journal of cancer, 122(3), 306–314. https://doi.org/10.1038/s41416-019-0602-7
   
6. Hussein, A. A., Helder, M. N., de Visscher, J. G., Leemans, C. R., Braakhuis, B. J., de Vet, H. C., & Forouzanfar, T. (2017). Global incidence of oral and oropharynx cancer in patients younger than 45 years versus older patients: A systematic review. In European Journal of Cancer (Vol. 82, pp. 115–127). Elsevier BV. https://doi.org/10.1016/j.ejca.2017.05.026
   
7. Bhatia, N., Lynde, C., Vender, R., & Bourcier, M. (2013). Understanding genital warts: epidemiology, pathogenesis, and burden of disease of human papillomavirus. Journal of cutaneous medicine and surgery, 17 Suppl 2, S47–S54
   
8. Chan, Y.M., Ismail, M.Z.H. & Khaw, WF. Factors influencing the prevalence of cervical cancer screening in Malaysia: a nationwide survey. BMC Women’s Health 23, 389 (2023). https://doi.org/10.1186/s12905-023-02553-3
   
9. Works Cited Ramakrishnan, S., Partricia, S., & Mathan, G. (2015). Overview of high-risk HPV’s 16 and 18 infected cervical cancer: Pathogenesis to prevention. In Biomedicine & Pharmacotherapy (Vol. 70, pp. 103–110). Elsevier BV. https://doi.org/10.1016/j.biopha.2014.12.041
   
10. Genital Warts (Condylomata Acuminata): Background, Pathophysiology, Etiology. (2025). https://emedicine.medscape.com/article/763014-overview?form=fpf
    
11. Human Papillomavirus (HPV) Vaccines – NCI. (2024). In www.cancer.gov. https://www.cancer.gov/about-cancer/causes-prevention/risk/infectious-agents/hpv-vaccine-fact-sheet
    
12. Parent Concerns About HPV Vaccine Safety Increasing – NCI. (2021). In www.cancer.gov. https://www.cancer.gov/news-events/cancer-currents-blog/2021/hpv-vaccine-parents-safety-concerns
    
13. Schmuhl, N. B., Mooney, K. E., Zhang, X., Cooney, L. G., Conway, J. H., & LoConte, N. K. (2020). No association between HPV vaccination and infertility in U.S. females 18-33 years old. Vaccine, 38(24), 4038–4043. https://doi.org/10.1016/j.vaccine.2020.03.035 

Sexual health is a vital part of overall well-being, yet for many, the topic of sexually transmitted diseases (STDs) remains surrounded by stigma, silence and misinformation. This often leads to delays in seeking medical help, increasing the risk of complications and further transmission.

In Singapore, the issue is more common than many realise. In 2024, there were 151 new HIV cases [1] — the lowest annual total since 1998 — yet over half were diagnosed at a late stage, pointing to a worrying trend of delayed detection. Among notifiable sexually transmitted infections [2] (STIs), chlamydia remains the most commonly reported [3], followed by syphilis and gonorrhoea.

These numbers serve as a reminder: STDs are more widespread and often overlooked than we think. The first step to protecting your health is being informed. In this blog, we break down the facts about common STDs: how they spread, the symptoms to look out for, when to get tested, and the treatment options available.

What are Sexually Transmitted Diseases (STDs)?

STDs, also referred to as STIs, are infections that primarily spread through sexual contact. This includes vaginal, anal or oral sex. In some cases, it can be spread through skin-to-skin contact.

While “STD,” and “STI” are often used interchangeably, the term STI is more accurate in many cases. This is because not all infections cause disease or symptoms. In fact, someone may have an infection and pass it on without even knowing.

How do Sexually Transmitted Diseases spread?

Bacteria, viruses or parasites are the known causes of STDs. As such, they are most transmitted through:

• Unprotected vaginal, anal or oral sex
• Genital-to-genital contact
• Sharing needles or syringes
• During childbirth (mother to baby)
• In rare cases, through blood transfusions or organ transplants

It is important to remember that STDs cannot spread through casual contact such as hugging, sharing food or using the same toilet.

What are the common Sexually Transmitted Diseases?

Although STDs are common in Singapore, social stigma combined with a lack of awareness often results in many cases going undetected. This is especially common in the early stages, where the disease may not cause noticeable symptoms. 

Knowing the common types, how they are caused and what to look out for can help you seek timely testing and treatment. Some of the common STDs are:

STD	CAUSE	WHAT IT IS	KEY CHARACTERISTICS / APPEARANCE
Chlamydia	Bacteria (Chlamydia trachomatis)	A common bacterial infection affecting the genitals, rectum or throat.	Often silent. It may cause abnormal discharge, pain during urination or pelvic pain.
Gonorrhoea	Bacteria (Neisseria gonorrhoeae)	A bacterial infection that can affect the genitals, rectum and throat.	Yellow or green discharge, painful urination or sore throat (if oral).
Syphilis	Bacteria (Treponema pallidum)	A bacterial infection that progresses in stages, from sores to serious organ damage if untreated.	Painless sore, followed by rashes, fever and in late stages, neurological or heart issues.
Genital Herpes	Virus (Herpes Simplex Virus – HSV-1 or HSV-2)	A viral infection that causes recurrent sores on the genital or oral area.	Painful blisters or ulcers on or around the genitals, anus or mouth. It may recur after treatment.
Human Papillomavirus (HPV)	Virus	A group of viruses, some of which cause genital warts or lead to cervical and other cancers.	Genital warts (small bumps, often clustered). However, most strains are asymptomatic.
HIV	Virus (Human Immunodeficiency Virus)	A virus that weakens the immune system and can lead to AIDS if untreated.	Flu-like symptoms early on. However, later stages involve fatigue, weight loss and recurrent infections.
Hepatitis B	Virus	A viral infection affecting the liver, which can be transmitted sexually or through blood.	May be silent. Some experience fatigue, jaundice or liver inflammation.
Trichomoniasis	Parasite (Trichomonas vaginalis)	A parasitic infection commonly affects the genital tract.	Foul-smelling vaginal discharge, itching and irritation. But it is often asymptomatic in men.

What are the signs and symptoms of Sexually Transmitted Diseases?

Many STDs are asymptomatic, especially in the early stages. This is why regular screening is important if you are sexually active. When symptoms appear, they may include:

• Flu-like symptoms (fever, fatigue, swollen glands)
• Genital sores, blisters or warts
• Itching, redness or swelling in the genital area
• Lower abdominal or pelvic pain
• Pain during intercourse
• Pain or burning during urination
• Rectal pain, discharge or bleeding
• Unusual vaginal or penile discharge

What happens if Sexually Transmitted Diseases are left untreated?

Whether symptoms are mild or asymptomatic, it is crucial not to ignore the possibility of an STD. Many infections can silently progress and cause serious long-term health consequences.

This includes:

• Chronic pain – pelvic pain [4], testicular discomfort and pain during intercourse are possible long-term effects of untreated infections. These symptoms can persist even after the infection is cleared. It may also affect daily functioning and quality of life.

• Infertility – infections like chlamydia and gonorrhoea can spread to the reproductive organs, causing pelvic inflammatory disease (PID) in women and epididymitis in men. These conditions can result in permanent damage [5], making it difficult or impossible to conceive naturally.

• Pregnancy complications – STDs during pregnancy [6] can lead to miscarriage, preterm birth or low birth weight. Some infections, like syphilis or herpes, can also be passed from mother to baby during childbirth. This may potentially cause serious neonatal infections or congenital abnormalities.

• Organ damage and systemic illness – some infections can progress to affect the heart, liver, brain and nervous system. This is especially risky with syphilis [7], hepatitis B/C [8] and HIV [9]. 

The good news is that many STDs can be easily treated if caught early. That is why seeking timely medical attention is crucial, as it can improve the outcomes of the treatment while safeguarding your sexual health.

How are Sexually Transmitted Diseases diagnosed?

Doctors will initially begin the diagnostic process with a medical evaluation. During this stage, doctors may ask questions such as:

• The symptoms you are experiencing
• How long have you experienced these symptoms
• Risk factors, such as lifestyle
• Your medical history
• Your sexual history, which includes how many partners you have had

These answers will then help doctors determine the combination of methods tailored to the type of infection. It may include:

• Blood tests – detect antibodies, antigens or DNA/RNA for infections like HIV, syphilis, herpes and hepatitis B/C.

• Urine tests – use Nucleic Acid Amplification Tests (NAATs) to identify bacterial DNA for chlamydia or gonorrhoea.

• Swab tests – PCR-based swabs for genital areas, throat, rectum or sores. It is often used for chlamydia, gonorrhoea, herpes or HIV.

• Multiplex PCR panels – they offer comprehensive screening for multiple infections from a single sample.

When should you get tested for STDs?

Early detection saves lives, prevents complications and most importantly, stops transmission. As such, here is when you should consider getting tested for an STD:

• After a possible exposure – if you have had unprotected sex, engaged in a new or casual partner or suspect your partner may be infected, then it’s recommended to get yourself tested. Testing should follow the recommended windows as below:
  • Retesting for chlamydia 1 to 3 weeks after the initial test (even if the first result came back negative).
  • Retesting for syphilis 3 to 6 weeks after the initial test (even with a negative result from the first test).

• If you have symptoms – even if you are experiencing mild symptoms like burning sensation while urinating, unusual discharge, sores or rashes, this warrants immediate testing.

• For routine checks – Singapore’s National HIV Testing Recommendations advise that every adult (age 21 years and older) should get tested for HIV at least once in their lifetime. Meanwhile, higher risk individuals are encouraged to get tested every 3 to 6 months.

• When a partner tests positive – if your partner is diagnosed with an STD, do get tested immediately. Even in the absence of symptoms, STDs can still spread easily and silently.

How are Sexually Transmitted Diseases treated?

Being diagnosed with an STD can feel overwhelming. However, you are not alone and help is available.

Most STDs are treatable and many can be completely cured with the right medical care. For those that are not curable, effective treatments can help you live well, manage symptoms and prevent transmission to others. Starting treatment early not only protects your health, but also your future relationships and well-being.

Depending on the cause, STDs are treated through:

Bacterial STDs (curable)

• Chlamydia – typically treated with doxycycline for 7 days. Pregnant ladies who are diagnosed with this disease are treated with azithromycin.
• Gonorrhoea – often treated with antibiotics such as ceftriaxone, combined with azithromycin.
• Syphilis – penicillin is the standard treatment, with alternatives available for those allergic. 

Viral STDs (manageable, but not curable)

• Genital herpes – antivirals like acyclovir reduce outbreaks and transmission risk.
• HIV – requires lifelong antiretroviral therapy (ART). Over 90% of Singaporean residents on ART achieve an undetectable viral load, virtually eliminating transmission risk. 
• HPV – no cure, but vaccination helps. Additionally, HPV-linked cancers are monitored and managed.
• Hepatitis B/C – chronic cases are monitored and treated to manage symptoms and improve quality of life.

Why is follow-up care important?

Treatment is only one part of the journey towards better sexual health. Proper follow-up care plays a crucial role in ensuring that infections are fully cleared, chronic conditions are well managed and partners are protected from reinfection.

Whether your diagnosis was bacterial or viral, taking the right steps after treatment can safeguard your long-term health and support the well-being of those around you.

A comprehensive follow-up care involves:

STEPS	WHAT IT ENTAILS
Retesting to Confirm a Cure (for Bacterial STDs)	Even if symptoms have resolved, it is important to retest after treatment. It is typically done 2 to 4 weeks later, depending on the type of infection and your doctor’s advice. This is especially important for:ChlamydiaGonorrhoeaSyphilis Retesting ensures the infection has fully cleared and helps detect possible reinfection, which is not uncommon. For example, some studies show up to 20% of people treated for chlamydia may get reinfected within a few months, often unknowingly.
Ongoing Monitoring (for Chronic Viral STDs)	For viral infections such as HIV, herpes, HPV and hepatitis B/C, follow-up care is ongoing and vital. These infections may not be curable, but they can be effectively managed with regular medical support. Monitoring typically includes: HIV – regular blood tests to check viral load and CD4 counts. Adhering to ART can reduce viral load to undetectable levels, which means zero risk of transmission to others through sex.Hepatitis B/C – periodic liver function tests and ultrasounds may be needed to check for signs of liver damage, cirrhosis or cancer.Herpes and HPV – monitoring focuses on symptom control and regular screening to catch potential complications early.
Partner Notification and Support	If you have been diagnosed with an STD, it is crucial to let your sexual partner(s) know, even if you are no longer in contact. This may feel uncomfortable, but open communication helps stop the cycle of reinfection and protects others from unknowingly spreading an infection. You do not have to do it alone. In Singapore, many clinics and local non-governmental organisations (NGOs) offer:Anonymous partner notification servicesCounselling and educational resourcesSupport groups or helplines

Final Thoughts

STDs are more common than many people think. What is even more unfortunate is that it often goes unnoticed until complications arise. But the truth is: most STDs are treatable and many are completely curable, especially when caught early. Even chronic infections like HIV or herpes can be managed effectively with modern treatment, allowing individuals to lead healthy, fulfilling lives.

Unfortunately, many delay seeking help due to fear, shame or misconceptions. However, it’s important to remember that there is no shame in getting tested. In fact, prioritising your health is an act of self-respect and it protects those around you too. Like any other medical issue, STDs deserve to be handled with dignity, compassion and science-based care.

If you are experiencing potential symptoms of an STD, schedule a consultation with us today for a detailed diagnosis and treatment plan. 

References

1. Sexual Health. (2025). In Default. Default. https://www.nus.edu.sg/uhc/health-promotion/sexual-health
2. Sexually Transmitted Infections. (n.d.). In www.healthhub.sg. Retrieved June 30, 2025, from https://www.healthhub.sg/programmes/sexually-transmitted-infections
3. Chlamydia. (n.d.). In Communicable Diseases Agency. Retrieved June 30, 2025, from https://www.cda.gov.sg/professionals/diseases/chlamydia
4. Jennings LK, Krywko DM. Pelvic Inflammatory Disease. [Updated 2023 Mar 13]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK499959/
5. Tsevat, D. G., Wiesenfeld, H. C., Parks, C., & Peipert, J. F. (2017). Sexually transmitted diseases and infertility. American journal of obstetrics and gynecology, 216(1), 1–9. https://doi.org/10.1016/j.ajog.2016.08.008
6. Kumar, M., Saadaoui, M., & Al Khodor, S. (2022). Infections and Pregnancy: Effects on Maternal and Child Health. Frontiers in cellular and infection microbiology, 12, 873253. https://doi.org/10.3389/fcimb.2022.873253
7. Tudor ME, Al Aboud AM, Leslie SW, et al. Syphilis. [Updated 2024 Aug 17]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK534780/
8. Hepatitis B and the liver: What to know. (2024). In www.medicalnewstoday.com. https://www.medicalnewstoday.com/articles/does-hepatitis-b-attack-the-liver
9. Neurological Complications of HIV. (n.d.). Retrieved July 1, 2025, from https://www.hopkinsmedicine.org/health/conditions-and-diseases/hiv-and-aids/neurological-complications-of-hiv 

When was the last time you thought about your cervical health?

For many women, it rarely crosses the mind, especially when there are no symptoms. Life gets busy, appointments get delayed, and screening often slips to the bottom of the list. Yet cervical cancer doesn’t wait. It develops quietly, often without warning, and by the time symptoms appear, it may already be advanced.

In Singapore, cervical cancer remains one of the top ten cancers affecting women [1]. But it is also one of the most preventable. The key lies in early detection — and that begins with a simple, routine test: the Pap smear.

Despite widespread availability and decades of medical evidence supporting its effectiveness, screening rates in Singapore are still not where they should be. Some women are unsure when to start or how often to go. Others feel anxious or embarrassed, or don’t know what the procedure involves. This lack of awareness and confidence can lead to delays in diagnosis and missed opportunities for early treatment.

This guide is here to change that. Whether you are 25 and preparing for your first test, or 45 and unsure if you are overdue, this article offers a clear and practical overview of Pap smears in Singapore. We will explain what the test is, why it matters, who needs it, how often it’s recommended, and where you can get it done. 

Understanding Pap Smears

Cervical cancer screening can feel unfamiliar or even intimidating, especially if it’s your first time. But understanding what a Pap smear is and how it works is the first step toward making confident, informed choices about your health. Here is what the test involves and how it compares with another common screening method: the HPV test.

What is a Pap smear?

A Pap smear is a screening test used to detect abnormal changes in the cells of the cervix [2]. These changes, if left untreated, can develop into cervical cancer over time. During the test, a healthcare provider uses a small brush or spatula to gently collect cells from the cervix. The sample is then sent to a laboratory for examination under a microscope.

The main goal of a Pap smear is to find early warning signs — cellular changes that aren’t yet cancer, but could become cancer if not managed. Detecting these abnormalities early allows for simple and effective treatment, long before cancer has a chance to develop.

The procedure is quick, typically taking less than five minutes. It may feel slightly uncomfortable, but it should not be painful, and no recovery time is needed afterward.

Pap Smear vs HPV Test — What’s the Difference?

While both the Pap smear and HPV test are used in cervical cancer screening, they test for different things and are recommended at different stages of life. Understanding the distinction helps clarify which test you need and why.

Aspect	Pap Smear	HPV Test
What it checks for	Abnormal or precancerous cells on the cervix	Presence of high-risk HPV strains that can cause cervical cancer
Purpose	Detects early cellular changes	Detects the virus that causes those cellular changes
Recommended age group	Women aged 25–29	Women aged 30–69
Screening interval	Every 3 years	Every 5 years
Used for	Early detection of abnormal cells	Identifying high-risk HPV before cell changes occur
Can it be done together?	Sometimes recommended as a co-test depending on history	Yes, often combined with Pap smear in women over 30

Both tests play a role in safeguarding cervical health. Your doctor will recommend the appropriate test based on your age, screening history, and overall risk profile.

Cervical Cancer in Singapore

Cervical cancer remains a serious yet largely preventable health concern for women. The availability of screening and vaccination has significantly improved early detection, but the burden of the disease persists — particularly when regular screening is delayed or skipped. In Singapore, the patterns of diagnosis and the factors that increase risk highlight the ongoing need for awareness and timely intervention.

Prevalence and Statistics

According to the Singapore Cancer Registry, cervical cancer ranks among the top ten most common cancers in women [3]. Each year, around 200 women are diagnosed, and approximately 70 lose their lives to the disease [4]. Although the incidence has declined over the decades—thanks to improved access to Pap smears and the introduction of HPV vaccination—the rates are still concerning, particularly among women who do not undergo regular screening.

Data shows that the risk of cervical cancer increases with age, and many of the cases diagnosed are in women who have either never been screened or have not had a Pap smear in the last five years. This underlines the importance of consistent follow-up, especially in women aged 30 and above.

Risk factors

Several well-established factors can increase a woman’s risk of developing cervical cancer. Understanding these risks is key to recognising the importance of regular screening:

• Persistent HPV infection — the most significant risk factor. High-risk strains of the human papillomavirus (especially HPV 16 and 18) are responsible for the majority of cervical cancer cases [5].

• Smoking — chemicals in tobacco can damage cervical cells, making them more susceptible to HPV-related changes [6].

• Early sexual activity or multiple sexual partners — these factors increase the likelihood of HPV exposure.

• Weakened immune system — conditions like HIV [7] or long-term use of immunosuppressive medication can reduce the body’s ability to fight HPV infections.

• Lack of regular screening — women who have never had a Pap smear or have infrequent screenings face a significantly higher risk of late-stage diagnosis.

• Long-term use of oral contraceptives — some studies suggest a slightly increased risk after five or more years of continuous use [8].

While not all risk factors can be controlled, regular screening and HPV vaccination remain the most effective tools for prevention and early detection of cervical cancer.

National Guidelines for Cervical Cancer Screening

Cervical cancer screening is not a one-size-fits-all process. In Singapore, national guidelines are tailored to maximise the benefits of screening while minimising unnecessary procedures. The Ministry of Health has established age-based recommendations to ensure that women receive the most suitable test at the appropriate time.

Understanding these guidelines can help you stay on track with your screenings, avoid confusion about when to start or stop, and ensure you’re receiving the most relevant care for your age and risk profile. Here are the recommended screening ages and intervals [9]. 

Women aged 25 to 29

Cervical screening is recommended for women based on their age, and sexual history:

• Women aged 25 years old, and above who have ever had sexual intercourse should begin regular cervical cancer screening at 25 years old.
• Women who have never had sexual intercourse do not require cervical screening. However, if they experience symptoms such as abnormal vaginal bleeding, then they should consult a doctor

Additionally, this group of women is encouraged to undergo a routine pap smear every 3 years. At this age, Pap smears are preferred over HPV tests because younger women are more likely to clear HPV infections naturally, and over-testing may lead to unnecessary interventions.

Women aged 30 to 69

Women between the ages of 30 to 69 should undergo an HPV test every 5 years if the result is negative. The HPV test is more accurate in detecting high-risk HPV strains, and is now the primary screening tool for women in this age group. It can identify risk earlier, even before any visible cellular changes occur.

Women in both age groups should ensure that their screenings are up to date, even if they have no symptoms and feel well. Regular screening is preventive, not reactive—it’s meant to catch changes before they cause harm.

Women who have had HPV Vaccination

Women who have received the HPV vaccine should continue to follow the same screening schedule as those who are unvaccinated.

Immunocompromised women

Women with weakened immune systems, including those on long-term immunosuppressive therapy, may require more frequent screening. These cases should be assessed, and managed individually by a gynaecologist.

Special Considerations

Women over 69

Women in this age group may stop screening if they have had two consecutive negative HPV tests in the last 10 years, with the most recent test within the past 5 years. Those with a history of abnormal results may still require continued monitoring.

Meanwhile, women with a history of treatment for CIN 2, CIN 3, or adenocarcinoma in situ (AIS) should continue routine screening for at least 20 years, even if this extends beyond the age of 69 years old.

Women who have had a hysterectomy

The need for continued cervical screening depends on the type of hysterectomy, and the woman’s medical history. This includes:

Total hysterectomy for benign conditions

Further cervical cancer screening is only needed if:

• The woman has a history of normal cervical cytology.
• Histopathology confirms the cervix was benign with no precancerous or cancerous changes.

Subtotal (partial) hysterectomy

Cervical screening should continue according to the national screening guidelines, as the cervix remains in place.

Hysterectomy where cervical histology is unknown

For women in this group, a baseline vaginal vault smear is recommended. However, if the result is normal, then no further screening is necessary.

Histology of cervical intraepithelial neoplasia (CIN)

If the excision margins were involved or not adequately assessed, follow-up should be guided by a gyneacologist. In general, vault smears should be taken at least annually.

Additionally, if CIN (Cin 1/2/3) was completely excised at the time of hysterectomy:

• Vault smears should be done annually for 5 years.
• Then, every 2 years for an additional period as advised by the clinician.

Preparing for a Pap Smear

Feeling uncertain before a Pap smear is completely normal, especially if it’s your first time. Knowing how to prepare can help ease any anxiety, ensure the most accurate results, and make the experience as smooth as possible.

Optimal Timing

The best time to schedule a Pap smear is about 10 to 20 days after the first day of your periods, when you are not menstruating. While it is still possible to perform the test during light bleeding, heavy menstrual flow may interfere with the accuracy of the cell sample. If your cycle is unpredictable, let the clinic know in advance so they can advise on the best timing.

Before the Test: What to Avoid

To ensure the best quality sample, it’s recommended to avoid the following 24 to 48 hours before your appointment:

• Sexual intercourse — seminal fluid and friction can temporarily affect cervical cells and obscure results.

• Douching or vaginal washes —these can disrupt the natural environment of the cervix and wash away or alter the cells that need to be examined.

• Tampons, vaginal creams, suppositories, or lubricants — these products can interfere with sample collection and analysis.

If you are unsure whether your recent activities could affect your results, speak with your healthcare provider before the test. It’s also perfectly acceptable to ask questions during the appointment or request a female provider if that makes you more comfortable.

Being well-prepared not only helps your doctor perform the test efficiently but also increases the likelihood of a clear and conclusive result — avoiding the need for a repeat test.

The Pap Smear Procedure

Understanding what happens during a Pap smear can help reduce uncertainty and make the experience more manageable. The test itself is quick and usually takes only a few minutes. While it may feel unfamiliar or slightly uncomfortable, it is not typically painful — and your doctor will guide you through each step. 

What to Expect During the Test

You will begin by lying on an examination table, typically with your knees bent and feet placed in stirrups. A device called a speculum is gently inserted into the vagina to hold it open, allowing the doctor to clearly view the cervix.

Using a small, soft brush or spatula, the doctor will collect a sample of cells from the surface of your cervix. This may cause a slight scraping sensation or mild pressure, but it usually lasts only a few seconds. Once the sample is collected, the speculum is removed and the procedure is complete.

The entire process takes less than five minutes.

Is It Painful?

Most women describe the test as mildly uncomfortable rather than painful. Some may feel pressure or cramping similar to menstrual discomfort, especially if it’s their first time or if they are feeling tense. Taking slow, deep breaths and trying to stay relaxed can help ease any discomfort during the exam.

If you experience significant pain at any point, let your doctor know immediately, as it could indicate an underlying issue that may need further attention.

Being informed and knowing what to expect can make the experience much less stressful. If you have concerns or specific preferences — such as having a female doctor or being talked through the process in advance — don’t hesitate to request this when making your appointment.

Interpreting Pap Smear Results and What Happens Next

Once your Pap smear is complete, the collected sample is sent to a laboratory for analysis. Results are usually available within one to two weeks and will be shared with you by your doctor.

Pap smear results typically fall into one of three categories:

• Normal (negative) — this means no abnormal cells were found, and you can continue routine screening as advised based on your age.

• Abnormal — this indicates that some changes were detected in the cervical cells. It does not mean you have cancer, but further testing may be needed to determine the cause and whether treatment is necessary.

• Unsatisfactory — in some cases, the sample may not contain enough cells or may be obscured by blood or mucus. Your doctor may recommend repeating the test to ensure a clear reading.

If your result is abnormal, the next steps depend on the type and severity of the changes. Your doctor may recommend:

• A repeat Pap smear after a short interval
• An HPV test to check for high-risk viral strains
• A colposcopy, a procedure that allows the cervix to be examined more closely under magnification
• A biopsy (if further investigation is needed)
  

Timely follow-up is essential, even if you feel well. Many cervical cell changes cause no symptoms but can progress silently over time. 

Cervical Cancer Screening in Singapore

Cost and convenience should never stand in the way of essential healthcare. While many women assume that cervical cancer screening is expensive or hard to access, the reality is quite the opposite — Pap smears and HPV tests are widely available across Singapore, often at highly subsidised rates.

For those seeking more personalised care, many private women’s clinics and GP practices offer Pap smears as part of health screening packages. At Ardennes Health, we provide discreet, comfortable, and professionally guided Pap smear screening in a calm, patient-centred setting. Whether you are coming in for your first test or a routine follow-up, our team is here to ensure you feel informed, supported, and cared for at every step.

With accessible options across both public and private sectors, there’s no reason to postpone your screening. What matters most is staying on schedule — because early detection saves lives.

Taking Charge of Your Cervical Health

Cervical cancer is one of the few cancers that can be prevented through early detection and timely treatment — and the Pap smear remains one of the most effective tools in achieving that. Yet, many women continue to miss out on screening due to uncertainty, discomfort, or the misconception that it’s unnecessary in the absence of symptoms.

Pap smear is a quick, safe, and reliable test that can detect changes in cervical cells long before they pose a serious threat. When combined with regular HPV testing and follow-up care, it offers women a powerful layer of protection against a disease that often develops without warning.

If you are due for a Pap smear or simply unsure where to begin, schedule a consultation with us for confidential, professional care tailored to your needs.

References 

1. Cervical cancer. Retrieved May 6, 2025, from https://www.singaporecancersociety.org.sg/learn-about-cancer/types-of-cancer/cervical-cancer.html 
2. What is a pap test? Cleveland Clinic. Retrieved May 6, 2025, from https://my.clevelandclinic.org/health/diagnostics/4267-pap-smear 
3. Singapore cancer society. Retrieved May 6, 2025, from https://singaporecancersociety.org.sg/index.php 
4. Cervical Cancer – What It Is. SingHealth. Retrieved May 6, 2025, from https://www.singhealth.com.sg/patient-care/conditions-treatments/cervical-cancer 
5. Okunade, K. S. (2020). Human papillomavirus and cervical cancer. Journal of Obstetrics and Gynaecology: The Journal of the Institute of Obstetrics and Gynaecology, 40(5), 602–608. https://doi.org/10.1080/01443615.2019.1634030 
6. Smoking and cervical cancer. Australian Government Department of Health and Aged Care. Retrieved May 6, 2025, from https://www.health.gov.au/our-work/tobaccofacts/smoking-and-cervical-cancer#:~:text=Chemicals%20from%20smoke%20change%20your,cells%20of%20women%20who%20smoke. 
7. Hewavisenti, R. V., Arena, J., Ahlenstiel, C. L., & Sasson, S. C. (2023). Human papillomavirus in the setting of immunodeficiency: Pathogenesis and the emergence of next-generation therapies to reduce the high associated cancer risk. Frontiers in Immunology, 14, 1112513. https://doi.org/10.3389/fimmu.2023.1112513 
8. Oral contraceptives (Birth control pills) and cancer risk—Nci. (2018, March 1). [cgvArticle]. https://www.cancer.gov/about-cancer/causes-prevention/risk/hormones/oral-contraceptives-fact-sheet 
9. Why annual pap smears are history – but routine ob-gyn visits are not. (n.d.). Retrieved May 6, 2025, from https://www.acog.org/womens-health/experts-and-stories/the-latest/why-annual-pap-smears-are-history-but-routine-ob-gyn-visits-are-not 
10. Enhanced screen for life(Sfl). Ministry of Health. Retrieved May 6, 2025, from https://www.moh.gov.sg/managing-expenses/schemes-and-subsidies/enhanced-screen-for-life/ 

Influenza, more commonly known as the flu, is a contagious respiratory illness caused by influenza viruses. In Singapore, the flu is fairly common, given the hot and humid weather all-year-round, creating a conducive environment for viruses to survive and circulate easily. 

Flu vaccinations remain the most effective way to prevent influenza and its complications. It not only reduces the likelihood of falling ill but also limits the severity of symptoms if infection occurs. Moreover, getting vaccinated helps reduce the spread of the virus in the community as it protects those who are unable to receive the vaccine, such as very young infants or individuals with specific medical conditions. In this article, we’ll look into flu vaccinations in Singapore, who needs them, and why. 

Understanding the Flu: Spread and Symptoms

Influenza is an acute viral infection caused by influenza viruses, which primarily affect the respiratory system. There are four main types of influenza viruses, A, B, C, and D, but only types A and B are responsible for seasonal flu outbreaks in humans [4]. These viruses are highly infectious and have the ability to mutate rapidly, resulting in new strains that can vary from year to year.

Influenza spreads mainly through droplets expelled when an infected person coughs, sneezes, or talks. These droplets can land in the mouths or noses of nearby individuals or be inhaled into the lungs. The virus can also spread through contact with contaminated surfaces, such as door handles or shared devices, followed by touching the face. Because it can be transmitted before symptoms appear and up to a week after falling ill, influenza is particularly difficult to contain without proactive measures like vaccination and good hygiene practices.

Potential complications of influenza include:

• Pneumonia — a serious lung infection that can be life-threatening, especially in the elderly and those with chronic illnesses.

• Sinus and ear infections — particularly in children.

• Exacerbation of chronic conditions — such as asthma, diabetes, and heart disease.

• Hospitalisation or death — in severe cases, particularly among vulnerable populations.

Why is the flu so common in Singapore?

The flu is relatively common in Singapore for the following reasons:

• Tropical climate — Because of Singapore’s constant warm and humid climate, influenza viruses can circulate all-year-round. 

• High population density — Singapore is a densely populated urban society, which increases chances of person-to-person transmission.

• International travel hub — The country is well-known for being an international travel hub, increasing risk of imported flu strains.

• Enclosed environments — Enclosed, air-conditioned spaces are common in Singapore, and are conducive spaces for virus survival and transmission.

Who Should Consider a Flu Vaccine?

Influenza vaccination is recommended for everyone aged 6 months and older, with rare exceptions. The Ministry of Health (MOH) in Singapore [5], along with global health authorities such as the World Health Organization (WHO) [6], advises annual flu vaccination as a key preventive measure. This is because influenza viruses evolve constantly, and the vaccine is updated regularly to offer protection against the most common circulating strains.

While the general population can benefit from vaccination, certain groups face a significantly higher risk of developing serious complications from the flu. For these individuals, the flu vaccine is not only a preventive measure, it can be life-saving.

Elderly Individuals (65 years and Above)

Older adults are more vulnerable to severe flu-related illnesses [7]. With age, the immune system weakens, which minimises the body’s ability to fight infections effectively. Influenza in the elderly is more likely to lead to hospitalisation, pneumonia, and, in some cases, death. Annual vaccination offers critical protection by reducing the severity of illness and the risk of complications.

Young Children (6 months to Under 5 Years)

Young children, particularly those under five years of age, have less developed immune systems, which makes them more susceptible to influenza and its complications, including febrile seizures and respiratory infections [8]. The flu vaccine helps to strengthen their immunity and reduce transmission in childcare settings and homes.

Pregnant Women

Pregnant women are more prone to severe flu symptoms and complications, especially in the later stages of pregnancy [9]. Importantly, the flu vaccine also provides protection to the unborn child, with antibodies passed from mother to baby. Vaccination is safe during any trimester and is strongly recommended as part of routine maternal care.

Individuals with Chronic Medical Conditions

People living with chronic conditions such as diabetes, asthma, chronic lung disease, heart disease, or compromised immune systems are more likely to experience complications from the flu [10]. Influenza can exacerbate existing conditions and lead to longer recovery times. Annual vaccination helps lower these risks and prevents disease flare-ups triggered by flu infection.

Healthcare Workers and Caregivers

Those who work in healthcare or provide care to vulnerable individuals, such as the elderly or chronically ill, are at increased risk of contracting and spreading influenza. Vaccinating this group not only protects them but also helps safeguard the health of the people they care for.

When’s the best time to get a flu vaccination?

There is no hard-and-fast rule when it comes to getting a flu vaccine. However, there are certain instances where it may be more beneficial for you, such as:

• Peaks in flu circulation — In Singapore, ideal times to get a flu vaccine would be in April, to protect against the mid-year spike, and October to protect you until the end of the year, when flu more commonly spreads. 

• Before traveling — Getting a flu vaccination right before a trip can help prevent you from falling ill and putting a halt on your holiday. 

• Before the school term starts — Schools are high-risk environments for flu transmission, and getting your child vaccinated ensures a good start to their school term, protecting them from infection.

• Before medical procedures — If you expect to be hospitalised or have a compromised immunity, getting a flu vaccination will be ideal for extra protection and optimal outcomes while you heal from your procedure. 

Addressing Common Misconceptions

Despite widespread public health campaigns and scientific evidence, several misconceptions about the flu vaccine persist. These misunderstandings can discourage people from getting vaccinated; as a result, they may put themselves and others at risk. Here are some common myths associated with influenza vaccines.

“The Flu Vaccine Can Cause The Flu”

This is one of the most persistent myths. In reality, the flu vaccine used in Singapore contains inactivated (killed) viruses or fragments of the virus that cannot cause illness. These components are designed to trigger an immune response, which helps the body build protection without causing infection.

Some people may experience mild side effects after vaccination, such as a low-grade fever, fatigue, or soreness at the injection site, but these are signs that the immune system is responding to the vaccine, not symptoms of influenza. The flu vaccine cannot give you the flu.

“Healthy Individuals Don’t Need the Vaccine”

It’s a common belief that flu vaccination is only necessary for the elderly or people with chronic illnesses. While high-risk groups are more likely to experience severe complications, healthy individuals can still get infected and suffer from uncomfortable symptoms, time off work or school, and, in rare cases, complications like pneumonia.

Moreover, healthy individuals can transmit the virus to others, including family members or colleagues who may be more vulnerable. Vaccinating healthy people contributes to community protection and helps break the chain of transmission.

“Vaccination Is Unnecessary If It’s Not Flu Season”

Unlike temperate countries with clear flu seasons, Singapore experiences influenza activity throughout the year, with peaks typically seen from May to July and November to January. This makes it important to stay protected regardless of the time of year.

Waiting for a “flu season” in Singapore can lead to missed opportunities for prevention. As immunity builds about two weeks after vaccination, timely vaccination, before known peak periods or ahead of travel to countries experiencing seasonal outbreaks, is essential for effective protection.

Potential Side Effects and Safety

The flu vaccine has a strong safety track record and is generally well-tolerated. Still, knowing what to expect can help you feel more confident about your decision.

Common Side Effects

Most people experience no issues after their flu shot. If side effects do occur, they are usually mild and go away within a couple of days. These may include:

• A sore or slightly swollen area around the injection site
• Low-grade fever
• Mild fatigue or muscle aches

These are normal immune responses and a sign that your body is developing protection.

Rare Side Effects

Severe reactions to the flu vaccine are extremely rare. In isolated cases, people may have allergic responses, such as hives, swelling, or breathing difficulties, usually within minutes of the injection.

Our clinical team monitors every patient briefly after vaccination and is fully equipped to manage any adverse reaction safely and promptly.

Why Flu Vaccination Matters Now More Than Ever

At Ardennes Health, we offer seasonal influenza vaccinations as part of our commitment to preventive care for individuals and families.

Influenza continues to be a significant public health concern in Singapore, as it affects people across all age groups. With year-round flu activity and seasonal surges, the importance of annual vaccination cannot be overstated. The flu vaccine offers reliable protection — not only reducing your risk of falling ill but also helping to prevent severe complications, hospitalisations, and the spread of the virus to others. 

If you are unsure about whether the flu vaccine is right for you, our medical team is here to provide clear, personalised guidance based on your health needs. Book an appointment (link to contact us page) with us today for a consultation. 

References 

1. Flu measures. (22nd April 2008.). Ministry of Health. Retrieved April 7, 2025, from https://www.moh.gov.sg/newsroom/flu-measures/ 
2. Drobnik, J., Pobrotyn, P., Witczak, I. T., Antczak, A., & Susło, R. (2021). Influenza as an important factor causing increased risk of patients’ deaths, excessive morbidity and prolonged hospital stays. Archives of Medical Science : AMS, 19(4), 941–951. https://doi.org/10.5114/aoms/138145 
3. Influenza vaccination services offered by community pharmacists under new sandbox initiative. (n.d.). Ministry of Health. Retrieved April 7, 2025, from https://www.moh.gov.sg/newsroom/influenza-vaccination-services-offered-by-community-pharmacists-under-new-sandbox-initiative/ 
4. CDC. (2024, September 27). Types of influenza viruses. Influenza (Flu). https://www.cdc.gov/flu/about/viruses-types.html 
5. Protocols and enhanced screening measures to prevent cross-border spread of influenza into singapore. (6th March 2025). Ministry of Health. Retrieved April 7, 2025, from https://www.moh.gov.sg/newsroom/protocols-and-enhanced-screening-measures-to-prevent-cross-border-spread-of-influenza-into-singapore/ 
6. Strengthening influenza vaccination policies and programmes. (n.d.). Retrieved April 7, 2025, from https://www.who.int/news/item/04-02-2025-strengthening-influenza-vaccination-policies-and-programmes 
7. Flu and older adults. (2022, June 14). National Institute on Aging. https://www.nia.nih.gov/health/flu/flu-and-older-adults 
8. CDC. (2024, September 26). Respiratory viruses and young children. Respiratory Illnesses. https://www.cdc.gov/respiratory-viruses/risk-factors/young-children.html 
9. Oseghale, O., Vlahos, R., O’Leary, J. J., Brooks, R. D., Brooks, D. A., Liong, S., & Selemidis, S. (2022). Influenza virus infection during pregnancy as a trigger of acute and chronic complications. Viruses, 14(12), 2729. https://doi.org/10.3390/v14122729 
10. American Lung Association. Flu symptoms and risk factors. Retrieved April 7, 2025, from https://www.lung.org/lung-health-diseases/lung-disease-lookup/influenza/symptoms-causes-and-risk 
11. Kim, T. H. (2014). Seasonal influenza and vaccine herd effect. Clinical and Experimental Vaccine Research, 3(2), 128–132. https://doi.org/10.7774/cevr.2014.3.2.128