Over 20,000 post-vaccination Covid cases in Kerala district has Centre worried

Officials at Pathanamthitta district, home to Sabarimala shrine, say the breakthrough infections could indicate that vaccine strategy is working since high risk people are covered.

Representational image | A beneficiary receives a dose of the Covid-19 vaccine at a vaccination centre, in Kerala in July 2021 | ANI
Representational image | A beneficiary receives a dose of the Covid-19 vaccine at a vaccination centre in Kerala in July 2021 | ANI

New Delhi: The tiny Kerala district of Pathanamthitta has so far reported over 20,000 breakthrough infections, or infections in people vaccinated against Covid-19, officials in the district administration have told ThePrint.

Of these, 5,042 infections happened after the patient had received both doses of the vaccine, among which 258 tested positive two weeks after being fully vaccinated. Similarly, 14,974 cases occurred in people who had received only one dose, of which 4,490 tested positive after two weeks of taking the shot. The duration of a fortnight is significant since it takes that long for the human body to generate antibodies against the virus.

The district has been administering both the indigenous Covaxin and AstraZeneca’s Covishield.

Confirming the numbers, Pathanamthitta District Collector Dr Divya Iyer said, “We have been doing regular reviews on this. It is possible that the breakthrough infections actually show that our vaccination strategy has been appropriate … we have targeted those that needed to be covered and were at high risk.”

The generally accepted definition of breakthrough infections is those that occur two weeks after both doses of vaccines have been administered, Dr Iyer said.

The district has a large number of senior people in residence, as was pointed out by the central team that recently travelled there during its trip to Kerala to assess the Covid-19 situation in the state.

“We have so far vaccinated 86 per cent of our [entire] population with one dose and 51 per cent with both doses of the vaccine. Every month we send about 50 samples for sequencing and so far we have not detected any newer variants than the delta variant,” she added.

The matter of breakthrough infections in Kerala was flagged by the central team in its report to the Government of India. In his letter to Chief Minister Pinarayi Vijayan, a copy of which is with ThPrint, Union Health Minister Mansukh Mandaviya said Wednesday: “Effective monitoring of adherence to covert appropriate behaviour post vaccination is essential coupled with the need for samples of breakthrough infections to be submitted to INSACOG labs for regular genome sequencing.”


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Breakthrough infections not entirely bad news

The six-member central team stated that the micro containment done in the district is working better because of the hilly terrain.

“As per data shared by state, as on 30 July ‘21 the number of cases/deaths reported was 130268 and 520 deaths. The CFR [case fatality rate] was 0.40%. The TPR [test positivity rate] as on 30th July 21 was 9.1%. The topography of district Pathanamthitta is somewhat different from other districts of the state. It has significant amount of hilly terrain with scattered population. In addition, there is substantial amount of tribal population. Therefore, micro CZ [containment zone] strategy has been working better in the district compared to rest of the state. Pathanamthitta has one of the highest percentage of senior citizen population in the country,” it said in its report.

While breakthrough infections are a cause of concern, particularly because of SARS-CoV-2’s history of rapid mutations and the probability of some of those changes making vaccines less effective against the virus, it is also a fact that during clinical trials, both Covaxin and Covishield were tested on their efficacy in preventing serious disease or hospitalisations.

One positive aspect of the breakthrough infections, according to Dr Iyer who is trained in medicine, is that it is probable that had these people not been vaccinated, many of them would have ended up with a serious infection.

“With our limited vaccine availability, we have been prioritising people who are high risk, frontline workers, old people, those with comorbidities. One way of looking at this is we have managed to reduce the severity of infections, and prevented hospitalisation or any other undesirable outcomes in the people most at risk. Our TPR is currently about 7-8 per cent and twice a week we have a review at the level of the chief minister.”

Pathanamthitta has been reporting about 500-700 cases daily. In the last 24 hours, it reported 536 new infections and two deaths. So far, the district has reported 1,33,346 confirmed cases and 533 deaths.

This report has been updated following a clarification from Pathanamthitta’s District Collector Dr Divya Iyer that of the over 20,000 cases of infections to occur post vaccination, 253 meet the scientific criterion for breakthrough cases.

(Edited by Manasa Mohan)


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