09 April 2020

Transactional Immunity

That phrase/term comes up at least once a week on the "Law&Order" re-runs. Looking it up, finally, one finds it's what used to be called, on the TeeVee shows at least, "blanket immunity". Every now and again the ADA makes a really bad deal, by granting immunity to a witness for 'other crimes' outside of that prosecution. It turns out the witness is also a perp with many, now immunized, bad behaviors. Face plant time. What sort of immunity can be expected from a Covid-19 vaccine, if one can be developed?

Contrary to what many folks think vaccination, on the whole isn't lifelong. Of those on the list, only measles is so named. Many are long lasting, though.

Amongst all the sites I lurk on, I found an intriguing comment:
There is not one vaccine for any coronavirus.

That'll get your attention. But is it true? The comment contained no link to a research paper or media report making that assertion. So I've let my fingers do the walking through the Yellow Googles. Let's see what I can find.

First, in "Nature" is a paper on vaccines for Covid-19.
If humans do develop immunity, how long does it last?

Immunity is short-lived for the coronaviruses that cause common colds; even people who have high levels of antibodies against these viruses can still become infected, says Stanley Perlman, a coronavirologist at the University of Iowa in Iowa City.

A bummer from the start. What, no herd immunity? I guess it's because civilians think that a virus is a virus, just like Rose, and you get one Polio shot for life (that's how most view it, anyway). Well, by now the informed civilian should know better.
The evidence is more equivocal for the two other coronaviruses that have triggered epidemics: those that cause severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). Perlman says his team has found that after people recover from MERS, their antibodies against the virus drop precipitously. He also says that his team has gathered data — not yet published — showing that SARS antibodies are still present in the body 15 years after infection. But it's not clear whether this immune response is enough to prevent reinfection. "We don't have good evidence of long-lasting immunity, but we also don't have really good data from both SARS and MERS," Perlman adds.

Still no better.

So, after one research paper, chalk one up, mostly, for the truth of the commenter's assertion.

Next, somewhat off point, but full of information is a "Wired" piece from early March. Doesn't directly address the question of existing coronavirus vaccine existence. It does offer up a bit unpleasant history of vaccines
In the 1960s, scientists at the National Institutes of Health were working on a vaccine against respiratory syncytial virus, or RSV, a common, very contagious virus responsible for most of the colds that infants and toddlers get. During clinical trials, some children who received the vaccine later went on to get terribly sick when they caught RSV in the wild. The vaccine produced an exaggerated immune response, causing extensive damage in their bodies. Two kids died.

Ah, just shove HCQ down everybody's throats. They'll be fine.

Wiki to the rescue (didn't come up early in the walk through the Yellow Googles). Well, not to refute the assertion, alas
Previous projects to develop vaccines for viruses in the family Coronaviridae that affect humans have been aimed at severe acute respiratory syndrome coronavirus (SARS) and Middle East respiratory syndrome (MERS). Vaccines against SARS[5] and MERS[6] have been tested in non-human animal models. As of 2020, there is no cure or protective vaccine for SARS that has been shown to be both safe and effective in humans.[7][8] According to research papers published in 2005 and 2006, the identification and development of novel vaccines and medicines to treat SARS was a priority for governments and public health agencies around the world.[9][10][11]

There is also no proven vaccine against MERS.[12]

And we already know that the Common Cold coronavirus has no vaccine. I'd wager because it's effects are sufficiently benign (well, close to anyway) that a vaccine would hardly be used.

In sum, my walk through the Yellow Googles doesn't gainsay the comment. And even if it did, there is a previous coronavirus vaccine, there isn't strong evidence that immunity would even be durable.

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