A new study published today shows covid reinfection from two different strains in a USA man.
Researchers are very concerned with either vaccine ineffectiveness or the virus learning to mutate rapidly in the body avoiding natural immune response.
The research confirms the 5th worldwide case of 2nd reinfection. This man was in Nevada. Researchers sequenced the genomes (meaning they studied the genetic make-up of the virus from both positive swabs) and found genetically significant differences in the 2 strains of virus.
SARS-COV-2 (the virus that causes covid) is a coronavirus which mutates frequently and fast. Some mutations are thought to be sloppy and cause the virus to mutate itself to a less severe strain, some are smarter. Other studies have explained strains that specifically seek and attack the lesser used ACE2 receptor organs, in turn causing the reactive immune system to take longer to notice.
In this study, the man was infected and tested positive in April. He tested negative twice in May on follow-up, then positive in June with a more severe strain that sent him to the hospital.
They found both viruses to be part of the clade 20C strain (identifying 5 common mutations) but the April virus had 5 further mutations, and the June virus had 6 further mutations off the reference genome clade 20C.
Other differences: April virus had 4 mutations not seen in June virus, and June virus had 7 mutations not seen in April virus.
The researchers hypothesized the more severe June strain could have been from increased viral load from a very high dose of the virus. Or the June strain was more virulent. Or third they seem to think this is most plausible - that anti-body dependant enhancement is the cause. (Immune cells become infected when they bind to the antibodies created from the first infection). Which is more scary to think about what that means in the future for vaccines. These researchers were very concerned stating warnings that vaccines may not be effective. Or worse, that it aids in allowing the virus to attack more stealthily while immune cells bind to antibodies created from the vaccines.
Science is never 100% accurate, so there is always a chance of reinfection from the initial infection. In this case though, if it were true, it would mean the virus would have mutated dozens of times in the mans body within a month to cause "reinfection" and more serious symptoms. We DON'T want this to be true! That would mean the virus can learn how to adapt in the body avoiding our natural immune response. If this is the case, no vaccine would ever prevent infection, we should be looking for a cure.
It took the world over 10 years to fully understand HIV (another RNA virus). Studies like this are not all doom and gloom though. It means that researchers can focus their efforts better, while humans should be focusing on immune health and wellness to beat it naturally.