The durability of the immunity built from Covid-19 infection or by Covid vaccination stays for around nine months, according to Indian Council of Medical Research (ICMR) director-general Balram Bhargava. He also added that multiple studies from India and abroad have given scientific evidence of this window.
"Based on several global and Indian scientific researches, if you get an infection, you are generally protected for 9 months," Balram Bhargava said while addressing mediapersons on Thursday.
The IMCR director-general further clarified that three Indian studies have revealed that the immunity stayed up to eight months . “There are three studies, two from ICMR and one from Mumbai, on 284 patients, on 755 patients and 244 that immunity persists for up to eight months, seven months and six months (respectively) and these are all published data from infection that occurred in 2020, 2021,” he said.
In addition to this, Bhargava also said that the new Omicron Covid variant is highly contagious compared to the Delta variant and stressed that the vaccination is important to fight the infection better. Bhargava also pointed that the vaccine can provide better protection but does not prevent the virus from infecting people. He further added that studies have also shown that the hybrid immunity developed in people who got the vaccine after naturally recovering from the infection was comparatively stronger.
“The transmission of Omicron is three or four times more than the Delta variant. In terms of the precautionary dose, we have to remember one important point — all Covid vaccines are disease-modifying and they do not prevent infection,” he said.
Also Read | India records first 'Omicron death' in Maharashtra, state govt denies
Bhargava also asked people to continue taking the necessary precautionary measures like wearing masks, avoiding mass gatherings, and following the Covid-19 guidelines at all times.
“If you have had an infection and vaccination, your immune response is more than only infection or vaccination. So the important thing is that vaccination is essential,” Bhargava said.
Decision on mixing vaccines for booster dose to be taken by Jan 10: ICMR
A final guideline on whether the mixing of Covid vaccines for the third jab is possible or not will be announced before January 10, said ICMR director-general, Dr. Balram Bhargava. The IMCR chief also said that the scientific advisory groups are currently holding extensive discussion to evaluate the safety and efficacy of the mixed doses.
“We are having extensive debates on... what are the vaccines available and which vaccines can be given in terms of safety and efficacy. We are analysing all the data that is available... whether it is going to be same vaccine or is it going to be different one,” said the ICMR chief.
“The Drugs Controller General of India and National Technical Advisory Group on Immunisation are meeting and that decision will be taken before January 10,” he added.
CMC Vellore is reportedly testing the mixing of Covishield and Covaxin doses through trials and SII is also conducting trials for testing the results of mixing Covavax booster over two doses of Covishield.
Also Read | Covid-19 India Update: New cases double up in last two days at fastest rate ever
The Centre has approved only Covishield and Covaxin under the government’s Covid immunisation programme so far though six other vaccines have also been given the emergency use authorisation (EUA). The EUA was granted to Serum Institute of India’s Covovax, Biological E’s Corbevax, Russia’s Sputnik-V, Cadila Healthcare’s ZyCoV-D, and two other jabs from Moderna and Johnson & Johnson. The Bengaluru-based Biological E’s Corbevax and Covovax were the latest additions to the list.
