New Delhi: Amid the ongoing vaccination drive against coronavirus, the Central government on Wednesday released data that shows that both the vaccines—Covaxin and Covishield—are working. As per the data released by the government, among those who received Covaxin, 695 tested positive after the second dose, which is 0.04 percent of the population that received the indigenous vaccine. Meanwhile, out of those who received Covishield, 5,014 tested positive after the second dose, that is, 0.03 percent of those who received the Oxford-AstraZeneca vaccine. India has so far administered 1.1 crore doses of Covaxin and 11.6 crore doses of Covishield.
Dr Chandrashekhar T, Chief Intensivist, Fortis Hiranandani Hospital Vashi, told The Sunday Guardian: “Covaxin is inactivated virus vaccine where the SARS-CoV-2 virus is used itself. But it doesn’t cause Covid-19 Infection, as it contains killed virus. The protein then triggers an immune response inside our bodies. That immune response, which produces antibodies, is what protects us from getting infected if the real virus enters our bodies. In this vaccine, the RNA of the weakened coronavirus has been utilized to induce the immune response from both B cells and T cells. But it is T cell immunized immunity that lasts longer. The Oxford-AstraZeneca (Covishield) COVID-19 vaccine uses a common cold viral vector found in chimpanzees known as ChAdOx1. It is developed to generate both B cell-mediated and T Cell mediate immunity. But it is the T cell-mediated immunity that lasts longer. When the vaccine is injected into a patient, it prompts the immune system to start making antibodies and primes it to attack any Coronavirus infection.”
Dr V.K. Paul, a member of health NITI Aayog and a part of the National Covid leadership team, while addressing a press briefing, said: “Breakthrough infections are sometimes happening about 3-4 in 10,000. This happens in foreign vaccines also. This incidence is very low… even if Covid happens after vaccination, it does not become serious,” he said, adding that these numbers occur in high-risk populations such as healthcare workers, so “incidence among common people will be even lower”.
“When the virus makes any changes in its RNA it is called a mutation. Now coronavirus is a mutating virus, it had mutated double and triple times in India. Therefore, what India needs are some genomic analytic studies to further understand the virus’s biology. With so many different information overloads that we have today, India needs to conduct a larger genomic sequencing study. Both vaccines are efficacious and will help protect the population from primary infection to a certain amount. These vaccines certainly prevent the severity of the infection and mortality as well. However, the vaccines available at present are speculated to give some protection against the mutant strains of SARS Covid-19. We need further research on the effectiveness of the vaccine on the mutated strain of Covid-19 virus infection,” Dr Chandrashekhar said. Several doctors The Sunday Guardian spoke to stressed that no vaccine will give “100% protection” from primary infection. However, getting vaccinated will ensure prevention from severity and mortality from the infection and disease.
Himanshu Sikka, an health expert at IPE Global, a think tank international development consulting firm, told The Sunday Guardian: “Both Covaxin and Covishield are approved and equally good. It has been very clear from the beginning that vaccines only reduce the severity of the infection and do not prevent the same. That’s why people need to keep following Covid appropriate behaviour even after vaccination. Further, it takes 2-3 weeks to get antibodies and one can get a severe infection in this period as well. Media can play a critical role by spreading this message and reduce skepticism. Trials for different vaccines for children under 18 are underway. Once such trials are over, the government will definitely open vaccination for those below 18 as well. So far, severe cases in children have been rare, so one should not unnecessarily panic or create panic.”