No evidence that people who have survived coronavirus have immunity
telegraph.co.uk
telegraph.co.uk
I'm no expert, but usually antibodies mean your body can fight the virus, right?
Rich Condit: This raises the issue, again, just briefly, that I was going to comment on earlier. It came up two letters ago, the phrase "correlates of protection", which is a really slippery concept, because it's really easy to make the assumption that "oh, you make antibodies and that's it". No. Or, "you make antibodies to this particular protein, that's all you got to do." No. Immunity that confers protection can be much more complicated than that.
Alan Dove: Everybody with HIV produces antibodies against HIV and they're great antibodies against the virus, and guess what: you still have HIV. So the antibodies in that case are not a correlate of protection. They're just something your body has done. On the other hand, if you're producing great antibodies against measles virus, you're probably protected. That's a very good correlate of protection.
Condit: So figuring out what actually protects you with any particular pathogen is a critical issue and not straightforward.
Brianne Barker: There have been a few times where we've mentioned "neutralizing antibodies" today. Neutralizing is one of the things antibodies can do. That means they can block viruses from getting in to cells or interacting with cells. And so sometimes the correlate is you have to make neutralizing antibodies, not just any old antibodies.
[1] - http://www.microbe.tv/twiv/twiv-594/ from about 1 hour and 7 minutes in
A: “If you get an infection, your immune system is revved up against that virus,” Keiji Fukuda, director of Hong Kong University’s School of Public Health, told the Los Angeles Times. “To get reinfected again when you’re in that situation would be quite unusual unless your immune system was not functioning right.”
https://thehill.com/changing-america/well-being/prevention-c...
* In a hearing before the House Oversight and Reform Committee on Thursday, Anthony Fauci, director of the National Institute of Allergy and Infectious Disease, was asked if people who have contracted the virus might now be immune. “We haven’t formally proved it, but it is strongly likely that that’s the case,” Fauci said. “Because if this acts like any other virus, once you recover, you won’t get reinfected.”
https://www.c-span.org/video/?470277-1/federal-health-offici...
* From the paper: "Antibody responses to SARS-CoV-2 in COVID-19 patients." "The positive rate for IgG reached 100% around 20 days after symptoms onset. The median day of seroconversion for both lgG and IgM was 13 days after symptoms onset. Seroconversion of IgM occurred at the same time, or earlier, or later than that of IgG. IgG levels in 100% patients (19/19) entered a platform within 6 days after seroconversion."
https://www.medrxiv.org/content/10.1101/2020.03.18.20038018v...
Study - Reinfection could not occur in SARS-CoV-2 infected rhesus macaques. https://www.biorxiv.org/content/10.1101/2020.03.13.990226v1
https://www.cnbc.com/2020/04/13/who-officials-say-its-unclea...
"A preliminary study of patients in Shanghai found that some patients had 'no detectable antibody response' while others had a very high response, said Dr. Maria Van Kerkhove, WHO's lead scientist on Covid-19. Whether the patients who had a strong antibody response were immune to a second infection is 'a separate question,' she added."
Is it likely there is at least some protection? Yes. At the same time there is reason to be cautious - the virus has been observed attacking and successfully entering T-helper cells and that does carry the potential for some really ugly long effects.
Now of course the whole herd immunity thing had become a political matter and in the US that means science goes right out of the window in favour of left/right blinders