Govt Used Faulty Data To Claim Fewer Post-COVID Vaccination Cases

The methodology used by the government is questionable, experts on virology said.

The central government has claimed that only two to four persons in every 10,000 inoculated with either of the two COVID-19 vaccines being used in India are seeing breakthrough infections. However, this was based on incomplete data – for nearly three months after vaccination began, the government's COVID-19 test form, used by both government and private laboratories, did not check if those being tested had been vaccinated. Cases of post-vaccination infection would therefore not have been detected and recorded, our ground investigation and review of documents revealed.

The methodology used by the government is questionable, experts on virology told us.

In clinical trials, both the two-dose COVID-19 vaccines Covishield and Covaxin being used have been shown to lower the risk of death, severe disease and mild infections in vaccinated individuals, even after only the first dose. Published phase-III trial results for Covishield showed a 70 percent vaccine efficacy in preventing symptomatic COVID-19 and 100 percent efficacy in preventing severe disease and death. Phase-III trial results for Covaxin have not yet been published, but the manufacturer claims a slightly higher vaccine efficacy of 78 percent.

Vaccine efficacy is the degree to which a vaccine prevents infection in vaccinated groups in closed, controlled clinical trials. Vaccine effectiveness, on the other hand, refers to how well a vaccine performs once it is approved for use and out in the real world.

In what appeared to be an attempt to demonstrate high effectiveness for both Covaxin and Covishield, however, the central government has used problematic data, we found. The number of persons receiving Covaxin and Covishield doses, and the number of breakthrough infections, ie COVID-19 cases reported by vaccinated persons after the first and second dose, were shared by Union health secretary Rajesh Bhushan at a press conference on 21 April.

"As everyone knows, there are two vaccines currently in use in our country. They prevent severe disease and death and definitely reduce infections. After vaccination, if we get infected, it is known as breakthrough infection," said Balram Bhargava, Director General of the Indian Council of Medical Research. Only 0.02 percent to 0.04 percent –or two to four per 10,000 – of vaccinated persons saw breakthrough infections after COVID-19 vaccination, which is a very small number, but even these few infections could be explained partly by the higher exposure of the infected persons compared to the general population, and to the ongoing second surge in India, added Bhargava.

He ascribed "this small number" to healthcare and frontline workers who were the first to be vaccinated. "They are prone to occupational exposure. But this is a very, very small number and not at all worrisome, and vaccination should continue," said Bhargava. "Secondly, the current highly transmissible second wave may also contribute little bit, or miniscule, to this percentage; otherwise this could have been even zero percent," he added.

Vinod Paul, member (health), NITI Aayog and head of India's COVID-19 task force, pointed out that these incidents of breakthrough infections were very low. Research was going on and even if these cases occur there will be no case of severe COVID-19, as per the data available with the government till date. The government was systematically collecting data on breakthrough infections, he added.

Until recently, however, ICMR's Specimen Referral Form (SRF), which laboratories were required to fill up when conducting a COVID-19 test, did not ask for information on whether the person being tested had been vaccinated against COVID-19.

On April 7 – nearly three months after India began its vaccination programme – the SRF form was amended to include questions on whether the person being tested had received the COVID-19 vaccine. If so, then which one? It also sought to know the dates on which the first and/or second doses had been received. This means that tests conducted for 81 days prior to7 April did not contain this information, a senior official at the ICMR admitted, asking not to be named.

Even now, the changed ICMR form has not fully made it to the ground, we found. The government's own National Centre for Disease Control's checklist of forms (accessible at this page) carries the old version of the ICMR SRF form, without fields for vaccination information. The websites of big diagnostic test providers, including Max Labs, SRL Diagnostics and Apollo Labs, still have the old ICMR form until today. This means that many who are testing positive for COVID-19 after getting vaccinated are still not being reflected in ICMR's data on breakthrough infections.

Siddharth Chakravarty, a 38-year-old researcher with an NGO, got his first dose of the Covishield vaccine at a government primary health centre in Bengaluru on 2 April. After experiencing mild symptoms, Chakravarty got himself tested for COVID-19 at a private lab in Delhi on 19 April and was positive. He was not required to give any details about prior vaccination, he said. (IndiaSpend reviewed his documents.)

B Sumana (name changed on request to protect identity), 69, got her first dose of Covishield on 3 April in Chennai. On 17 April, she experienced mild COVID-19 symptoms and got herself tested at a private lab. Again, no details on prior vaccination were sought. She then received a text message confirming receipt of her sample with a link to the ICMR's COVID-19 Sample Collection Management System portal, from which she could download her Sample Referral Form. In the personal details section was the question: Received Covid-19 vaccine? The form had already been filled out with the answer "no", even though she had never been asked the question, and had actually received one dose. She tested COVID-19 positive. (IndiaSpend has reviewed all her documents.)

At least two deaths from COVID-19 of vaccinated people have been reported in mainstream media; a father-son duo of doctors in Kalyan, Maharashtra who died on 17 April, had both received the first dose of a vaccine. Relatives said they had tested positive and died from COVID-19.

IndiaSpend sought a response from ICMR early on 22 April, asking what methodology was used to collate numbers of breakthrough infections, and seeking clarifications about facts uncovered by our ground reporting. The article will be updated should they respond.

"There is a World Health Organization guidance for conducting vaccine effectiveness trials in low and middle-income countries. This is absolutely not the way to measure it," said Gagandeep Kang, one of India's leading virologists. "There are ways to do even small trials for vaccine effectiveness, but this is not it. You can't first find people who test positive and go back to see if they were vaccinated. You need to start with the vaccinated population and see whether they get infected," she said. "In addition to the problems on the ground that you are pointing out, there will also be [vaccinated] people who test positive later. There will be (vaccinated) people who feel sick, but never get tested," she said

(This story was first published in IndiaSpend and has been republished with permission)