Medically Reviewed by Dr Jackie Lam, M.B.B.S (Singapore)
With the widespread uptake of COVID vaccination boosters, many individuals in Singapore have questions about the necessity of other vaccinations—particularly the flu vaccine. It’s understandable to wonder whether protection against one viral illness, like COVID-19, could also shield you from others.
However, COVID-19 and influenza are caused by entirely different viruses, and each requires its own line of defence. Understanding how each vaccine works and why both are recommended is essential to protecting your health, especially during Singapore’s annual flu season and amid the ongoing circulation of COVID-19.
COVID Vaccination vs. Flu Vaccination: What’s the Difference?
Both COVID vaccination and the flu vaccine aim to reduce the severity and spread of viral illnesses, but they target different pathogens. The COVID vaccination is designed to stimulate immunity against the SARS-CoV-2 virus, while the influenza vaccine targets specific strains of the influenza virus, which change each year based on global surveillance data.
Even if you’ve had all your COVID vaccination boosters, including updated versions for emerging variants, these do not offer protection against the flu. The immune response triggered by one vaccine does not cross over to protect against another virus, which is why separate immunisations are needed.
Why Annual Flu Vaccines Are Still Recommended
Influenza viruses mutate rapidly, which is why the flu vaccine is updated annually. Health authorities, including Singapore’s Ministry of Health and the World Health Organization, recommend yearly flu shots to protect against the most recent and prevalent strains.
Even if you’ve had your COVID vaccination, you’re still at risk of contracting the flu. The flu can lead to severe complications, particularly in vulnerable populations such as the elderly, young children, pregnant women, and those with chronic health conditions. A COVID-19 infection and an influenza infection can even occur simultaneously, increasing the risk of complications significantly.
Getting the flu vaccine annually reduces this risk and helps to prevent unnecessary hospitalisation. It’s especially important during times when both flu and COVID-19 are circulating.
Can I Get the COVID and Flu Vaccines Together?
Yes. In Singapore and many parts of the world, it is now common and safe to administer the flu vaccine and COVID vaccination during the same healthcare visit. Doing so helps maximise convenience and protection, especially for those with busy schedules.
Receiving both vaccines at once does not reduce the effectiveness of either. Side effects may include mild fatigue, soreness at the injection site, or low-grade fever—similar to the reactions experienced when receiving either vaccine alone.
Who Should Prioritise Both Vaccines?
While the COVID-19 vaccine remains essential for preventing serious COVID-19 complications, the flu vaccine is equally critical for those most at risk. Individuals who should ensure they are vaccinated against both illnesses include:
- Adults over the age of 60
- Children under 5 years old
- People with chronic illnesses (e.g., asthma, diabetes, heart disease)
- Healthcare workers
- Pregnant women
Singapore’s National Adult Immunisation Schedule (NAIS) includes both the influenza and COVID shot for eligible populations. Subsidies may apply for those under government health schemes such as CHAS, Merdeka, or Pioneer Generation.
Will My Immunity From COVID Vaccination Protect Me From the Flu?
No. Although both COVID-19 and the flu may cause similar respiratory symptoms like cough, fever, and fatigue, the viruses are genetically distinct. The COVID-19 immunization stimulates antibodies specifically against the spike protein of the SARS-CoV-2 virus. It has no efficacy against the surface proteins of influenza viruses. Assuming immunity to one means protection from the other is a misconception that could leave you vulnerable during flu season. For optimal protection, both vaccines are necessary.
Understanding Coinfections: The Danger of Overlapping Illnesses
A concerning scenario seen in recent flu seasons is coinfection, where individuals contract both COVID-19 and influenza simultaneously. Coinfections tend to result in more severe illness, longer recovery periods, and a higher chance of hospitalisation. Symptoms may become more intense, and pre-existing conditions may be aggravated.
Taking both the COVID vaccination and the flu vaccine is a preventive strategy that helps reduce the risk of such complications. It also helps protect those around you, particularly those who may not be eligible for vaccines themselves due to medical reasons.
How the Vaccination Strategy Supports Singapore’s Public Health Goals
Singapore’s public health authorities encourage vaccination as a cornerstone of disease prevention. By increasing coverage of both the COVID and flu vaccines, the country aims to reduce the healthcare burden during peak infection periods.
Vaccination reduces the spread of disease, decreases the load on healthcare infrastructure, and ensures that those who do fall ill are less likely to need hospital care. For working adults, students, and caregivers, it also means fewer days lost to illness and better overall productivity.
Where to Get Vaccinated in Singapore
Flu and COVID vaccinations are widely available at polyclinics, public hospitals, and private General Practitioner (GP) clinics. Many private clinics, like Keystone Clinic & Surgery, offer convenient appointments and combined immunisation visits.
Booking a vaccination at your GP also allows you to discuss any concerns you might have, receive a quick health review, and ensure your records are updated with the latest immunisation data. For adults and children alike, vaccinations can often be completed in a single visit.
Addressing Common Concerns About Getting Both Vaccines
Many individuals express concerns about taking two vaccines in one appointment. However, clinical data from both local and global studies confirm the safety and efficacy of co-administration. If you experience minor side effects, such as fatigue or mild muscle aches, they typically resolve within one to two days.
Another concern is the perception of vaccine fatigue—feeling overwhelmed by repeated doses. But both the flu vaccine and COVID boosters serve different protective purposes and are necessary for continued health resilience.
It is better to face temporary side effects than to risk a prolonged or severe illness that could lead to complications or missed responsibilities.
Conclusion
While your COVID vaccination offers critical protection against the coronavirus, it doesn’t cover you for seasonal influenza. With both viruses still circulating and the potential for coinfections, taking the flu vaccine—even if you’ve had your COVID boosters—is a wise and recommended health measure.
Vaccination remains the most effective tool for preventing severe illness and reducing transmission in the community. By staying up to date on both your flu and COVID shots, you’re investing in your own health, your family’s safety, and Singapore’s broader public health resilience.
Stay Protected All Year Round – Book Your Vaccinations Today
At Keystone Clinic & Surgery, we provide safe, convenient access to both flu and COVID vaccinations. Our team of experienced doctors can guide you on the best immunisation schedule for your age, health status, and lifestyle. Safeguard your health with trusted care and timely vaccinations. Book your appointment today at Keystone Clinic & Surgery and take a proactive step toward a healthier future.
References
Nicd.ac.za. The COVIDS-19 Vaccine and Flu Vaccine. https://www.nicd.ac.za/the-covid-19-vaccine-and-the-flu-vaccine/
Pursuit.unimelb.edu.au. You Can Get Your Flu and COVID Vaccinations at the Same Time, But What’s Best – One Arm or Two?. https://pursuit.unimelb.edu.au/articles/you-can-get-your-covid-and-flu-vaccinations-at-the-same-time,-but-whats-best-one-arm-or-two
Uhhospitals.org. COVID-19 and Flu Shot Spacing. Is It Needed?. https://www.uhhospitals.org/blog/articles/2021/10/covid-19-vaccine-and-flu-shot-spacing-is-it-needed
Lung.org. Flu Shot and COVID-19 Vaccine: Do I Need Both?. https://www.lung.org/blog/flu-shot-covid-19-vaccine