Post-vaccination protection: Annual booster shots the ‘new normal’: Prof. Vitharana  

  • Post-jab antigen levels/vaccine efficacy to wear away after 1-1½ yrs 

  • “SL will soon have to select most suited vaccine” 

By Aazam Ameen


Following reports from studies conducted in the United Kingdom (UK) which detail antigen levels of persons inoculated with Covid-19 vaccines, estimates show that the effectiveness of such vaccines will wear away after a period of one to one-and-a-half years, in which case annual booster shots will be required, The Sunday Morning learnt. 

Speaking to The Sunday Morning, Government parliamentarian, Lanka Sama Samaja Party General Secretary, and virologist Prof. Tissa Vitharana said that even though the information with regard to antigen levels was noted on the basis of partial information that is presently emerging from laboratories, he is inclined to accept the veracity of such findings. 

“Viruses, respiratory ones included, tend to undergo a series of changes over time. Therefore, fresh antigens are required to cover the range of a virus. This is why, for example, we see the annual administration of vaccines against influenza,” he explained. 

Prof. Vitharana also added that reports coming from the UK suggest that the duration of protection from Covid-19 vaccines is likely to be limited to one-and-a-half years, in which case a booster shot will be required. 

“Sri Lanka has very recently begun the administration of vaccines. Laboratories will have to follow up on individual subjects while considering demographic factors such as age groups and others, in order to assess the levels of antibodies present in their systems at different points in time. This will result in the observation of a trend. Based on this trend, we can project when it will be required to administer a booster shot,” he elaborated. 

Further, when queried as to whether the health authorities have considered these factors in terms of effectively administering vaccines, Prof. Vitharana claimed that despite his expertise, he has been completely left out from these matters. 

“For some reason which I cannot understand, I have become persona non grata with regard to these subjects,” he said. 

He also added that at this point of time, even though several manufacturers are producing numerous vaccines, Sri Lanka will have to, in due course, decide based on scientific studies, as to which vaccine is best for the country.