Covid19 immunity in people who have contracted the virus can last for many months as people who are infected with the virus produce antibodies of high-quality against the disease for a period of 5-7 months or even more after they were initially infected, according to a study published in the journal Immunity. These findings suggest that not all but many people who have recovered from the virus are immune to it for some time. The authors of the study also suggested that covid19 vaccines may be capable of providing immunity to people for a period greater than one or two weeks.
An immunobiologist at the University of Arizona Deepta Bhattacharya said that in one patient he has seen the immunity to the virus lasted for seven months after contracting the virus, and in few other people the covid19 immunity lasted for a period of 5 to 7 months. His team wrote in the report that they conclude that the body of a person who has been infected with covid19 produce neutralizing antibodies for a period of not less than five to seven months.
Bhattacharya’s team has been working, by using the help of county officials for testing of volunteers, since the end of April immediately after the blood test for covid19 was developed. Like most of the researchers, it was discovered by them that the antibodies to the virus increased immediately after the infection and then decreased. The reason for this according to Bhattacharya is that antibodies are created by B cells which after creation mature into plasma cells, and a ton of these plasma cells are short-lived. These plasma cells create a lot of antibodies; however, these antibodies do not provide any covid19 immunity.
Bhattacharya said that the best cells are those that are competing with each other, they are generally formed later and become long-lived cells. His team has tested around 30,000 people, some of whom have already been tested many times.
The covid19 virus has not been around for more than a year, so it’s difficult to tell how long its immunity will last. Bhattacharya believes that the most similar virus to covid19 was the first Severe Acute Respiratory Syndrome (SARS) coronavirus and some people who were infected by it are still immune to it seventeen years later. He added that if the new coronavirus is in any way similar to that coronavirus then the antibodies are expected to last for not less than two years at least.
Nearly 800 people died due to the first SARS coronavirus and around 8,000 were infected before the virus ended in 2004. Moreover, according to Bhattacharya people who were hit the worst by the covid19 virus had a greater immune response and create antibodies that were of a higher level than people who were mildly hit, but how long will their immunity last is not known. Moreover, the researchers didn’t check that if those people were capable of resisting being infected again.
The studies conducted on coronavirus until now don’t support the idea of herd immunity in the United States or any country over the world for that matter, as according to the World Health Organization (WHO) only 10% of the world’s population have been infected with the virus, therefore herd immunity is a long way off.