PETALING JAYA: Booster doses of vaccines are part and parcel of a long-term process of preventing infections or reducing severity of symptoms.
The efficacy of a vaccine wanes with time, according to virologist Dr Muhamad Afiq Aziz.
He said additional doses on a regular basis would keep the body’s immune system at its peak and thus be able to fight new infections.
Muhamad Afiq, who is with the Institute of Biological Science Research at Universiti Malaya, said the emergence of the Omicron variant of the Covid-19 virus, as well as other variants that may continue to surface in the future, showed that booster doses are essential.
He said the main reason for getting vaccinated against Covid-19 is not to fall seriously ill or succumb to the illness if infected.
He added that judging by the reduction in the need for hospitalisation or use of ventilators, as well as lower fatality rate, booster doses are effective.
“We need to get a booster dose. The level of antibodies in our body produced by vaccination goes down over time.
“Data from clinical trials shows that booster shots improve our immune response towards this virus,” he told theSun.
Muhamad Afiq likens it to the influenza vaccine. “The flu virus mutates regularly, so we need a new dose of the vaccine every year to stay protected against new strains,” he said.
However, the awareness on the importance of vaccination among Malaysians is still low, he added.
“From my observation, I find that many people get vaccinated only after being informed of the government’s ruling that only fully vaccinated shoppers are allowed to enter malls.”
Universiti Putra Malaysia consultant clinical microbiologist Dr Zamberi Sekawi said there may even be a need for a fourth dose of the vaccine.
He said efforts should also be made to enhance the efficacy of the vaccine to meet the threat from new strains of the virus.
“The virus has already mutated significantly. The current variant is very different from the original or ‘parent’ strain,” he said.
Zamberi added booster dose is effective in fighting the Omicron variant and he urged all those who are eligible to take the vaccine.
However, virologist Dr Sandy Loh of University Nottingham Malaysia said there may already be a need for a variant-specific vaccine to increase their effectiveness against newer strains.
“Can we keep up with the speed at which the virus is mutating and new variants emerging? Unfortunately, we have not been able to do it so far.”
Loh said there would come a time when a booster shot is needed at shorter intervals.
“This can only be avoided if we have a universally effective vaccine that can prevent any variant from infecting us.”
Loh added that when Covid-19 is declared an endemic disease, there is a likelihood that booster doses would be needed for many years.
“With the available vaccine, we may need to get booster doses every few months.
“If we do get one that will ensure efficacy for a year, like the flu vaccine, that will be an improvement,” she added.
