PETALING JAYA: Malaysia needs to plan ahead to administer Covid-19 vaccine booster shots considering the waning effect over time, say health experts.

       While the focus to vaccinate those who have not received their jabs including teenagers should be ramped up, they suggested immunity surveillance for those who need a booster shot to avoid wastage.

       Malaysian Medical Association president Dr Koh Kar Chai said booster shots were likely necessary as “the protective effects of vaccination will wane over time”.

       “This could be one of the reasons behind the high infections and deaths. But more data is needed,” he said.

       Dr Koh said healthcare workers and other high-risk groups should be given booster shots from October onwards based on the recommended interval of six months after full vaccination.

       “The government should ensure booster doses are available when needed.

       “More data is also needed on the vaccines with a longer-lasting efficacy,” he said, adding that the private procurement of vaccines should be allowed subject to approval.

       Dr Koh also called on Malaysia to be vocal on the need for a fairer distribution of vaccines globally.

       “Richer countries with an oversupply should help poorer nations. The World Health Organisation (WHO) should also take a tougher stand,” he said.

       Malaysian Public Health Physicians’ Association president Datuk Dr Zainal Ariffin Omar said Malaysia should do advance planning on administering booster shots.

       “We should start with the vulnerable groups and frontliners,” he said, adding that early next year would be a suitable time.

       But he said booster shots should only start after all the eligible population including teenagers were vaccinated.

       “The Health Ministry should conduct immunity surveillance to assess the immunity level in the population,” he said, adding that decisions must be made based on science and engagement between the government and health experts.

       Independent health policies expert Dr Khor Swee Kheng suggested a “targeted booster policy”.

       “Based on science and immunology, booster shots may be inevitable. But this does not mean that Malaysia should go for a blanket booster policy.

       “Only those who need a booster should be given.

       “If those with strong immune responses receive an unnecessary booster, they may suffer from hyper-immune reactions or a higher risk of side effects,” he said.

       Universiti Malaya’s virologist Prof Dr Sazaly Abu Bakar said all members of the adult population and adolescents aged 12 to 17 should be vaccinated first before considering booster doses.

       “We have to make early plans to purchase the vaccines for booster doses to avoid problems with the supply,” he said.

       Dr Sazaly said other than the waning effect of the vaccines, ineffective stimulation of memory immune response could also be possible behind the high infections and deaths.

       “It means the vaccine did not launch an adequate immune response to remember the antigens that previously activated it,” he said.

       UM professor of epidemiology and public health Dr Sanjay Rampal said the government could take the lead and start negotiating to secure booster shots in advance.

       “When purchasing booster shots, it is important to consider the vaccine effectiveness against newer Covid-19 variants,” he said.

       Dr Sanjay added that it was important for all countries to have access to vaccines, especially with newer strains emerging.

       “This is in line with WHO’s call for countries to complete the vaccination programme before considering booster doses to maintain vaccine equity,” he said.