There is no proof that getting it once conveys permanent immunity, some viruses just stick with you and come out when your immune system is weakened.
I have already heard that, and am asking one question. (Sorry if this is naive, I'm no virology expert!)
If the above happened to be true, how could a vaccine for it ever work?
Maybe the answer is obvious, and if so, I'm going to learn something about vaccines.
Some viruses don't act predictably, this new one being an example. Its obvious that its extremely unpredictable and thats why this particular epidemic is taking a deep toll on doctors and nurses.
I have been trying to figure out a good answer that expresses what I feel I know with accuracy, while not overreaching.
One area where there is a lot of activity is imune system adjuvants. There were discovered by looking at the way that some substances magnify the ability of the immune system to remember some things when they present themselves to the immune system the same time as something else.
These are substances that make the body remember a substance with an extra kick.. But from what little I know that can also be very problematic, its very complicated, the thing that seems to be killing people so frequently with covid 19 is an immune response thats delayed too long and then its too strong, the delayed, overstrong immune response is part of what is killing people.
Some viruses basically just effect peoples immune systems they deplete certain kinds of cells in the immune system. Example:
https://www.ncbi.nlm.nih.gov/pubmed/23087407This is an interesting article about the virus vaccine industry which explains why lots of viruses still have no vaccines.
Why are vaccines against many human viral diseases still unavailable; an historic perspective?
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7166819/Here is another one on the situation in 2006. (Right around the time of SARS-CoV-1 )
New viral vaccines.
https://www.ncbi.nlm.nih.gov/pubmed/16364754I'm not qualified to take much of a stab at this, as thats a subject I know very little on. What I know could be summarized in a few pragraphs. There are lots of reasons why a vaccine, even if it is available might not work in everybody or certain groups, even groups of the same age..
One thought - there are big moral and liability issues, a vaccine might be effective in some situations but not in others, if so, they likely dont want people to think they are protected when they are not. Also some vaccines seem (from what Ive read) actually make things worse if you get some other similar illness, it seems this happened with HPV vaccines made a few years ago The vaccine many people got was adquate protection for some strains but it put people at higher risk for HPV and I think also some cancers if they got others, So now there is a debate about what they should do.
There is a lot of focus on vaccines because at least in the past that was the most common way of fighting viral diseases.
But the economics of vaccines may not be what they want, take for example Gilead's treatment for hepatitis C. It cured the very costly disease but it was itself insanely costly.
With coronaviruses, they mutate very quickly, many coronaviruses mutate so much there is a very real chance that they would mutate into something else enough for a vaccine you got now to no longer to be effective against a very similar virus a few years from now.
Here is a good unknown question, why do people on ships tend to get it in such high numbers? Is it just them being confined in fairly close quarters? Because it seems those cuise ships were pretty spacious and once the coronavirus became an issue on some ships everybody was confined to quarters. But they still continued to have more and more people test positive. Maybe there is some aspect of ships that they all share that makes them an ideal environment for coronavirus transmission?
You won't know until mass testing for immune globuline reveals the true spread and whether it was enough to build any kind of herd immunity. But when I look at the current mortality figures especially for England, boy, that's not looking good. Something has started eating into the 15-64 year age bracket worse than any influenza in the past years. I hope it's the lockdown working when the curve flattens.