With an increasing number of breakthrough infections being reported in the State, some public health experts are of the view that a third (booster) dose of COVID-19 vaccine is required, especially for healthcare workers. However, opinion is divided on the issue.
Breakthrough infections are those that occur among people who have contracted COVID-19 despite being vaccinated.
Till August 26, Karnataka had recorded 14,421 breakthrough infections and 126 succumbed to the disease. According to data from the State Health and Family Welfare Department, while 11,881 infections and 109 deaths were reported among those who have taken the first dose, 2,540 infections and 17 deaths were reported among those who have been fully vaccinated till August 26.
M.K. Sudarshan, chairman of the State’s COVID-19 Technical Advisory Committee (TAC), said that in his personal opinion healthcare workers, who were inoculated in the first phase after vaccination was rolled out on January 16, need a booster shot now. “This is especially in the wake of a possible third wave hitting the State in October-November as predicted by the TAC in May 2021,” he said.
Pointing out that the issue was yet to be taken up for discussion in the TAC, Dr. Sudarshan said, “I personally feel a third dose will boost the confidence of healthcare workers to manage the third wave confidently. The State should write to the Centre in this regard.”
However, he was quick to add that it is a policy decision. “It will be based on need assessment and vaccine availability. With a major chunk of the population yet to be fully vaccinated and vaccination of children yet to begin, availability is limited. But a decision has to be taken at the earliest because even if the process of administering a third dose begins now, it will take two-three months,” Dr. Sudarshan asserted.
The Indian Medical Association (IMA) also has similar views. It has even written to the Centre on the need for a booster shot for healthcare and frontline workers. Srinivasa S., chairman of National IMA Standing Committee for Child Health, said a third dose is required as there are reports about waning vaccine immunity. “Healthcare workers, who were prioritised for vaccination in the first phase, should get a booster dose,” he said.
‘Not the solution’
However, TAC member Giridhar R. Babu, who also heads Lifecourse Epidemiology at Indian Institute of Public Health in Bengaluru, said, “Breakthrough infections after two doses is more of a reason why booster dose is not the solution.”
In a series of tweets on Friday, Dr. Babu said, “Vaccine efficacy is established against preventing death and reducing hospitalization. It will be mostly met with two doses. The assumption that a third dose will prevent infection when the first two doses have not is an untested one.”
“Trial data and real-world effectiveness data can tell what proportion are breakthrough infections. This can be monitored as background rate and see trends. In areas with many breakthrough infections, very few need hospital care and ICUs.”
Besides, “Most health care workers who have breakthrough infections have been either detected due to routine/mandatory testing or with minor illness. Their immune response has worked effectively with two doses. That is why they do not need hospitalization. How will a third dose help them?”
Meanwhile, the State-run Sri Jayadeva Institute of Cardiovascular Sciences in Bengaluru will soon start a study to assess the need for a booster dose of the COVID-19 vaccine.
Institute Director C.N. Manjaunath, who is also the nodal officer for labs and testing in the State’s COVID-19 expert committee, said the 200 healthcare workers at the institute, who had received their second dose in February, will be tested for the robustness and longevity of anti-SARS-CoV-2 antibodies in September second week.
“In the wake of all the discussion around a booster dose, we want to study how long the vaccine mediated antibody response will last,” he said.