Vaccines are regarded as one of the biggest miracles or rather, breakthroughs in medicine. It helps us build a stronger immune system that acts as a shield against infectious diseases; preventing us from contracting or potentially spreading them.
Reports from the World Health Organization show that about 10 million deaths have been prevented in 2010 to 2015 because of vaccinations delivered around the world. This is a powerful result, and it leaves us wondering just how different the world would be if the 500 million people who died because of the 1918 Spanish flu were vaccinated in time.
In this article, we speak to Infectious Diseases Specialist Dr. Loh Jiashen to learn more about the power of vaccines, and find out what are the essential ones Singaporeans are encouraged to take.
According to Dr. Loh, the average healthy adult do not need to receive a lot of vaccinations, but there are situations that call for it at different stages in life.
Touching on the types of common vaccines usually recommended, Dr. Loh said: “Routinely, TDaP vaccine (against diphtheria, tetanus and whooping cough) is recommended in all adults every 10 years. TDaP is also recommended in every pregnancy regardless of previous dosage received,” Dr. Loh shared.
“Influenza vaccines are recommended to be taken yearly, especially if one is at high risk of developing flu complications,” Dr. Loh added.
If you are wondering if all these vaccines can be taken together at once, the answer is usually yes, with a few exceptions.
“Many vaccines are coformulated to target multiple disease in one injection. The TDaP and MMR vaccine, one that infants aged around nine to 15 months usually get to prevent measles, mumps and rubella, are examples of coformulated vaccines,” Dr. Loh added.
However, it is important to note that there are also exceptions. For instance, the pneumococcal vaccines PCV13 and PPSV23 should be taken separately as they both counter overlapping strains of the pneumococcal bacteria.
Many wanted to know if they would be suitable to take the COVID-19 vaccine if they have an existing medical condition. Touching on this, Dr. Loh noted that it is generally a ‘yes’ for most medical conditions. For instance, hypertension, diabetes mellitus, asthma etc.
However, in the case of immunocompromised patients, there are three principles to be discussed and understood.
Dr. Loh explained: “Firstly, it is that the extent of the immunocompromised varies. Hence, vaccine eligibility must be individualized.
“Secondly, live vaccines are generally contraindicated in the immunocompromised or pregnant patient to avoid vaccine-related infection, which is an attenuated form of the infection caused by the live virus in the vaccine.”
“In this immunocompromised group, we recommend vaccination of close family members to form a non-transmitting protective bubble around the immunocompromised patient, who cannot receive the live vaccine. The classical example here is the varicella vaccine,” Dr. Loh added.
As for the third principle, Dr. Loh highlighted that there are immunocompromised conditions that are not permanent. As such, vaccination in these patients may be delayed until they exit the deep immunocompromised state. If non-live vaccine is administered in an immunocompromised state, it could lead to a suboptimal vaccine response.
Ever wondered why there are age restrictions for different vaccines? According to Dr. Loh, it is because they are made to prevent diseases that are likely to occur at different stages in life.
For instance, infants and young children are strongly encouraged to be vaccinated at a young age to prevent getting highly contagious diseases such as measles or mumps. Some of these vaccines remain highly protective for many years and are still effective even as the child enters adulthood.
Human papillomavirus (HPV) vaccination is also recommended in childhood and adolescents so that stronger immunity to HPV can be achieved prior to the start of sexual activity. The pneumococcal vaccine (PCV-13) is recommended in older adults where the consequence of infection tend to be more severe.
Bringing up another example with the dengue vaccine, Dr. Loh shared that the vaccine is recommended for those above the age of nine in endemic areas (where there is a higher prevalence of dengue). Dengue vaccination in seronegative individuals may also backfire and result in an increased risk of severe dengue fever infection subsequently.
With Singapore being an ageing population, it is also important for the elderly to get the appropriate vaccinations when they reach the recommended age group. After all, the risk of severe diseases increase with age and it is also when the immune system weakens, placing seniors at risk to fight off infections.
When asked for the most important vaccines seniors aged 65 and above should get in their silver years, Dr. Loh recommended the pneumococcal vaccines PCV-13 and PPSV-23, influenza vaccine. To prevent herpes or shingles, the zoster vaccine is also recommended.
To find out if it is time for you or a loved one to get vaccinated, consult your doctor or check out the national immunization guide here.
