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I found this link on the internet:

70 vaccines are getting ready for coronavirus: 3 very promising

Why is it that there will be vaccines before a cure? Shouldn't it be the other way around? What is the reason for the vaccine first then the cure?

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    @Gordon Thank you. I understand what you are saying. But why isn't the money being invested for the med that specifically cures COVID-19 or Corona virus by the Pharmaceutical companies who are targeting the vaccine first? – mvr950 May 4 at 14:30
  • @Gordon Wouldn't that help more people? – mvr950 May 4 at 14:31
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    Do you understand how vaccination works? – Bryan Krause May 4 at 18:18
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    The trouble with cures is that viruses can't (generally) be cured, as in, the viruses themselves cannot usually be targeted by medication. With bacteria it's easier because they are living beings so chemicals can be found which are poisonous to them but relatively harmless to us. Virus "cures", in most cases, don't actually destroy the virus itself, but they instead mitigate the damage the virus does, while the immune system can deal with the virus itself. – vsz May 5 at 8:22
  • "But why isn't the money being invested for the med that specifically cures" because throwing money at something doesn't always make it come true – Emobe May 7 at 13:55
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Your question contains a lot of misconceptions.

  • A cure is definitely possible
  • A cure could be found, proved, and proved safe, more quickly than a vaccine
  • People and firms that could be working on cures are choosing to work on vaccines

None of these are correct. Most virus-caused diseases have no cure: colds, Zika, Dengue, and so on. A tiny handful have treatments that can ease the course of the disease: you've heard of Tamiflu and so on. And some can be actually cured with medication. So the first assumption, that a cure exists to be found, is not a sure thing by any means, and is actually quite unlikely.

Then there is the matter of side effects, unintended consequences, and so on. We are pretty familiar with vaccinations by now. We know how to test that a vaccine doesn't cause other problems. But a cure often can have really bad effects. A drug that is supposed to lower your [blood pressure, heart rate, blood sugar, whatever] or raise your [immune response, whatever] might raise or lower it too much. It might cure one thing but give you a stroke or a heart attack. The immunotherapy that cured my 3-months-to-live melanoma also wiped out my thyroid and nearly killed me with a skin reaction. [I am fine with that trade, but the point is treatments can and do kill people. We only use them if the curing outweighs what the side effects do.] Cures have to be tested to understand all of these possibilities. In most cases we want to know the long term reactions -- and that means giving the drug and monitoring and studying for months or more. Plus, we give treatments to sick people, but vaccines to healthy people, so the side effects are even more of a big deal for a treatment.

And finally, the money and teams to work on a vaccine are entirely different than the money and teams who work on cures. So work is underway on cures too. It hasn't been set aside to focus on vaccines.

What you're observing is that everyone predicts a vaccine will come more quickly. It's a better understood area (we have vaccines for tons of viruses, but cures for very few) with less concern about hurting or killing the people we give it to. It's most likely the vaccine teams will succeed before the cure teams do. But it's not because there isn't any work happening on possible cures.

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    Another very important thing: cures help the people who are already sick. Vaccines help people prevent getting sick. If you have a dangerous disease that's likely to spread over most of the population, vaccines make far more health and economical sense. And for bonus points, having most of the people vaccinated protects the people who can't get a vaccine. Also, to be fair, we do have some anti-virotics that could be used broadly - but as you said, the side effects are pretty bad. Worth it if you have AIDS, but not exactly great to cure a common cold or the flu. – Luaan May 5 at 7:30
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    It is true that if I were forced to choose whether to invent a vaccine or a cure, I'd go for the vaccine because more people haven't caught it yet but are at risk to than are currently ill, and never getting something is better than getting it and then recovering. However nobody is making that choice, both are being worked on and funded. – Kate Gregory May 5 at 10:30
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    On the other hand, we also don’t have a vaccine for a good deal of viruses, such as HIV (in development since 1984), Ebola and Malaria. For the Dengue Fever, the EU approved the First-ever vaccination in 2018, after roughly 90 years of search for a vaccine. Of course, because vaccines for other viruses of the Corona type exist, we hope that with this solid background knowledge, it is possible to find a vaccine. Still, it might be that the current vaccines in development do not work. We might never find one. So it could be that treatment predates vaccine, or that we are left without either. – Narusan May 5 at 11:57
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    @Narusan Malaria isn't a virus. It's caused by a protist of the genus Plasmodium. – probably_someone May 5 at 14:40
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    @Narusan HIV is a special case because it has evolved a (vastly!) more sophisticated strategy for evading the immune system than any other known virus. And for other viruses (and other diseases) the question of finding a vaccine is (not exclusively, but) very much a function of the money you throw at it, and all your examples are sadly grossly underfunded because they disproportionately affect poor countries. Finding a vaccine for SARS-Cov-2 isn’t quite a safe bet, but on balance pretty likely. – Konrad Rudolph May 5 at 17:22
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Drugs are typically small molecules that interfere with some chemical process in the disease causing microbe, and therein lies the rub. Bacteria, fungi, protozoa, worms, etc. are sustained by their own complex systems of chemical reactions, largely independent of chemical systems that sustain us. That makes it easier to find a chemical that attacks something in the microbe's chemistry, but doesn't affect our own chemistry (much). Penicillin for example, targets an enzyme bacteria use to maintain their cell walls. Our own cells don't have cell walls in the same way bacteria do, and we don't use that enzyme, so a drug that blocks that enzyme in bacteria may cripple the bacteria without having (much) of an effect on our own cells.

Viruses on the other hand, are really just a bit of DNA or RNA wrapped in a coat of sugars, proteins, and fats. They don't have any life processes of their own. They simply piggy-back and subvert our own chemical systems. That means any drug that targets a chemical process used by the virus is likely to have bad side effects on the patient too. In some cases it is possible to create an anti-viral drug that attacks a protein unique (or mostly unique) to the virus. The problem is that this is a much narrower range of possible targets, and it tends to be specific to a single virus. Drugs like penicillin often work on whole families of bacteria. This is what makes finding a drug that "cures" viral diseases so hard.

However, living creatures have had to defend themselves against viruses for billions of years, so we've evolved sophisticated internal defenses against them. Even bacteria have a sort of immune system against viruses. When you are infected with a virus your body begins a race to mount an effective immune response before the virus does severe or even fatal damage to your body. Vaccines allow your body to begin mounting an immune response before you are actually exposed to the virus. Then if you are eventually exposed your immune system is able to shut the virus down much more quickly. Getting a workable vaccine is still tricky though, because you have to find substances that starts an immune response specific to the target virus in most people, but that doesn't also kick the immune system into an over reaction that itself can be very dangerous.

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    So COVID-19 virus could be used to make vaccines right? – mvr950 May 4 at 19:25
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    Right, but if you just inject people with COVID-19 you'll simply be giving them the disease, so that's not a great idea. You have to figure out some way to disable or modify the virus before you put it into people so that it can't cause the disease. The tricky part is that most of the ways of modifying the virus also change it enough that your immune system may not recognize the "real" virus when it comes along. – Charles E. Grant May 4 at 19:31
  • If you go back to the time when Smallpox was nearly endemic, some people would inoculate themselves with minute amount of viral material. If all went well, they'd get a mild, survivable case of the disease and then be immune for life. Here's a story of John Adams (eventually US Pres. John Adams) going through the process: doctorzebra.com/prez/z_x02smallpox_g.htm – Flydog57 May 5 at 6:22
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    @Flydog57, What made early vaccinations safer than getting a wild-caught case of the disease wasn't really the minuteness of the dose. The people who practiced vaccination collected material from patients who had only the mildest cases. In effect, they were breeding a safer form of the disease—passing it on from successfully vaccinated patients to new patients. Later (late 1700s) they discovered that innoculating people with cowpox was safer still, and it provided just as much protection. en.wikipedia.org/wiki/Smallpox_vaccine – besmirched May 5 at 13:07
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    P.S., "Vaccine" comes from the Latin, "vacca," meaning "cow." – besmirched May 5 at 13:09
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I don't believe we have the data to say that vaccines will be deployed earlier than an effective treatment.

Vaccine technology is old technology and the go to for most infectious diseases as there is a desire to prevent preventable illness. However, HIV was discovered in 1984 but we still don't have a vaccine against it though we have effective treatments. Some of the problems with a vaccine for HIV is that it's not a respiratory virus, and it mutates rapidly.

The SARS epidemic was in 2003 and we still also don't have a vaccine for that, and it's unclear if the new mRNA vaccines for COVID-19 will be effective or not as there has not been one deployed successfully before.

Most of our drugs used in treatment are small molecules but many of our modern biological drugs are synthetic humanised antibodies, and there is a lot of experience in developing such treatments in diseases such as Rheumatoid Arthritis, and Axial spondyloarthropathies.

To develop such antibodies to fight COVID-19 an animal (mouse) can be infected with SARS-CoV-2 and the subsequent antibodies are screened for effectiveness. Those most promising are humanised and then further developed for testing. Celltrion are using antibodies taken from recovered Korean patients.

Through a partnership with the Korea Centers for Disease Control and Prevention (KCDC), Celltrion initially identified and secured 300 different types of antibodies that bind to the SARS-CoV-2 antigen. These were then screened based on their ability to bind to the virus Spike (S) protein. Celltrion was then able to capture a total of 38 potent neutralising antibodies, of which, 14 were identified as most potent against SARS-CoV-2.

...

Ki-Sung Kwon, Head of R&D Unit at Celltrion said: “We are bringing our full resources and expertise to overcome this global health crisis and are glad to have identified these antibodies sooner than previously expected. These antibodies can recognise multiple epitopes, thus increasing the probability of neutralisation against viral mutations. Given the expedited development process of our antiviral antibody treatment, we anticipate moving to first-in-human clinical trials in July. We are also on track with the development of a ‘super antibody’ or ‘an antibody cocktail’ and the launch of a rapid diagnostic kit in the summer of this year.”

These would be expected to work like naturally developed antibodies that develop during the adaptive immune response to fight the infection.

https://www.drugtargetreview.com/news/60206/celltrion-selects-14-lead-monoclonal-antibodies-for-covid-19-treatment/

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    A mouse could be exposed to SARS-CoV-2 but it's very unlikely to be infected by it. Most viruses are specific to a particular species (e.g. not zoonotic, specifically animal to human). It is thought that SARS-CoV-2 most likely came from pangolins. It's possible that 20-70 years ago the ancestor to this virus was in bats. Cross species infection is very rare, fortunately. Viruses mutate to adapt to their host. SARS-CoV-2, although it has a mutation from its previous version allowing it to infect humans, has not yet acclimatised to us which is why the death rate is so high. – CJ Dennis May 5 at 4:24
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    Hamsters are being used. Also there are mice engineered with human ace2 receptors sciencemag.org/news/2020/04/… – Graham Chiu May 5 at 5:46

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