TheWinz said:
Using your logic, this article is 100% false, correct? After all, these are South Korean CDC researchers, and they are saying, with 100% certainty, that contracting the virus a second time is impossible. Not highly unlikely, not for only a set amount of time - they are saying never ever again.
That isn't what the article says.
Recurrent viral infections can occur by a number of mechanisms:
1. Reinfection due to an inadequate immune response to initial infection (related to viral and/or host factors, e.g. genetic susceptibility, immunosuppressive conditions or medications), or the virus evading the immune system. This would be a second infection with the same virus.
2. Reinfection due to a virus that has structurally mutated in the critical regions recognized by the first infection's antibodies. This would be a second infection due to a new strain.
3. Reinfection due to waning immunity. Antibody protection doesn't last forever, and the duration of immunity varies for different infections. This could also lead to a second infection with the original virus strain.
4. Reactivation of latent infection. Some viruses cause symptoms with initial infection, are temporarily contained by the immune system, but aren't completely killed off. A subset of viral populations hide out in areas inaccessible to the immune response. Years later they may reactivate, often when the immune system is impaired due to age, medications or concurrent medical conditions. Herpes, shingles and HIV are examples of
reactivation of the original infection.
The headline of the article is deceptive, implying none of these mechanisms is possible. But the meat of the article mostly refers to mechanism #4, and alludes to #2 not being evident on genetic analysis thus far. But they don't exclude that possibility altogether:
In the future it could be possible that the coronavirus mutates and infects people who have previously overcome it, similarly to the flu.
More importantly, there's nothing in the article that says #1 & #3 are impossible. And no reputable scientist would give 100% guarantee this early in our understanding of SARS-CoV-2 virology. Unlike "hard" sciences and math, medicine is rarely so cut and dry.
FTR, based on what we know about other coronavirus infections, I expect short-term reinfection is pretty unlikely. And early in this thread there were posts explaining SARS-CoV-2 mutates less rapidly than some other viruses, including other coronaviruses and influenza. Plus we don't have clear cut evidence of anyone infected twice. So hopefully our immune response can keep it at at bay a while, at least until a vaccine is developed.