THIRUVANANTHAPURAM: The fourth national serosurvey on Covid, which shows how many people developed immunity against the infection, is a wake-up call for Kerala which has a large number of vulnerable people. The report made public partly on Tuesday says that the state still has a large number of people who are not immune to the infection while several states have almost achieved herd immunity. It also explains why the state continues to report a large number of new positives.
While it is noted that the pandemic waves did not cause a collapse of the health system, the threat of a third wave could still be damaging if the vaccination drive is not ramped up to create immunity among the susceptible population, according to health experts. The Indian Council of Medical Research survey found that two-third of the population in the country has got immunity by way of infection or through vaccination.
It also means that there are still around 40 crore people who are vulnerable to infection. The survey details regarding individual states are not known yet. However, it was found in the previous three surveys that Kerala has a low level of seroprevalence (proportion of people with immunity).
“The seroprevalence in the state will be low in this survey also. As there are more uninfected people, it will take time to bring down the baseline. But it should not be seen as a bad thing because we could manage the caseloads as per the capacity of our health system,” said Dr K P Aravindan, a leading pathologist and member of the expert panel on Covid. The state has seen an increase in the number of new positive cases and test positivity rate of late. It reported 17,481 new cases with a TPR of 11.97% on Wednesday. It was 16,848 and 11.91%, respectively, on Tuesday.
Immunologist and public health expert Dr Padmanabha Shenoy said only 45% of the state’s population have resistance to the virus and one-third of it was achieved by way of double dose of vaccination.
He arrived at the proportion of the immune population by considering the possible infection death rates and the excess deaths reported by various sources.
“The maximum number of Covid-infected people in the state would be around 1.25 crore. That leaves a large number of the population still susceptible to the virus. This is the reason for the prolonged high plateau. This plateau is a perfect launch pad for another uptick if we are letting our guard down. Even a small mistake can result in loss of gains we have made,” he said.
The health experts vouched for Covid vaccination as the only way to provide long-term protection. According to them, the presence of the delta variant of the virus would require more people to be vaccinated to achieve herd immunity.“Earlier, it was considered 50-70% immunity in the population offers herd immunity. But since we have virus variants in circulation, our target would be to vaccinate 80% of the adult population at the earliest,” said Dr Aravindan. Only around 20% of the population has been covered with two doses of vaccine so far.