Why Kerala should keep tabs on breakthrough infections
KOCHI: While instances of breakthrough Covid infections among the vaccinated are a source of worry, Kerala too is witnessing a large number of such cases, especially among the health workers. According to experts, it is very important to track and investigate these rising number of infections, especially in the case of clusters, to identify new strains or mutated forms of the virus. In terms of daily Covid cases, Kerala is at the top of the list compared to other states.
With Kerala continuing to report high number of infections, experts believe there is a need to keep a close watch on the situation including breakthrough infection. More than 1.2 crore vaccine doses have been administered in state. Over 27% of people in the state have received at least one dose, and nearly 7% have been fully vaccinated.
“There are many cases where people have picked up the infection even after first dose of vaccination and after getting both the doses as well. Rather than the prevention of the infection, the factors considered for designing the vaccines were based on hospital admissions including ICU and ventilators. In such case, breakthrough infections are expected to an extent, but if the vaccines are able to bring down the number of those seeking hospital care in severe condition, then it meets the purpose. Since Covid puts a lot of stress on the healthcare system, it is important to bring down these numbers,” said a pulmonologist based in Thiruvanathapuram. Breakthrough infections can be in two ways — not generating antibodies even after taking the jab and even after generating the antibodies one is exposed to a dangerous and different strain of the virus. In both the cases, vaccination has proved ineffective.
“Antibody generation varies from individuals. Therefore, there will be at least some, who have not generated antibodies even after taking both doses. These people can be infected with the same old Covid strain with severe illness. Many studies had revealed that vaccination is ineffective against the Delta strain. A new mutated strain can also cause breakthrough infections,” said Monu Varghese, a pulmonologist here.
Most of the breakthrough infections reported in the state are due to the Delta strain. A study on breakthrough infections conducted among health workers at the Thiruvananthapuram Medical College in April found that most of those infected had Delta strain. Since health workers were among the first to be vaccinated, it is prudent to monitor this group for breakthrough infections.
“Breakthrough infection in a vaccinated population is something which we need to keep a close watch on. Identifying clusters of these infections should trigger investigation into the vaccine management system and genome sequencing to identify emergence of variants with immune escape capabilities,” said Anup R Warrier, infectious disease expert. According to a member of the Covid task force, the state is keeping a watch on regions with high number of cases and also genome sequencing is done among selected clusters by coordinating with the district medical officers.