As 'researchers using conventional approaches have struggled to develop effective vaccines against a number of pathogens, particularly viruses, that cause both acute (Influenza, Ebola, Zika) and chronic (HIV-1, herpes simplex virus) infection', why weren't RNA vaccines earlier 'explored as a way to more rapidly and cheaply produce vaccines for these diseases, particularly in response to emerging outbreaks'? Why are clinical trials only now commencing to be 'carried out or are ongoing on mRNA vaccines for influenza, cytomegalovirus, HIV-1, rabies and Zika virus'?

Five things you need to know about: mRNA vaccines | Horizon: the EU Research & Innovation magazine | European Commission

1. They’re a whole new type of vaccine

If an mRNA vaccine was approved for coronavirus, it would be the first of its type. ‘It's a very unique way of making a vaccine and, so far, no (such) vaccine has been licenced for infectious disease,’ said Prof. Bekeredjian-Ding.

  • $\begingroup$ Because they were only invented quite recently, perhaps? $\endgroup$ – jamesqf Apr 4 '20 at 4:30
  • $\begingroup$ This is not a biological question. It has to do with politics, policy, etc. Is like asking "why is health care not free now?" In addition, the OP seems to answer their own question, so this seems like a sketchy way of gaining reputation... $\endgroup$ – TumbiSapichu Apr 4 '20 at 23:33
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    $\begingroup$ @TumbiSapichu I'm uncertain why you think that I answer my own question. It appears unmannerly to allege this "a sketchy way of gaining reputation". I'm genuinely curious. $\endgroup$ – NNOX Apps Apr 11 '20 at 6:59
  • $\begingroup$ Clinical trials take a long time and depend upon continued investment at each stage. It's a very new technology, relatively speaking, and one fraught with financial risk. It may be difficult to answer without specifics about a particular disease and therapy. $\endgroup$ – Alex Reynolds Apr 11 '20 at 8:46
  • $\begingroup$ @TumbiSapichub is correct in his explanation of why this not a biological question in the terms of reference of SE Biology which is concerned with questions about the mechanisms of biological processes that are capable of objective answers. He should not, however, have made the remark in his final sentence. He presumably misunderstands that it was a third party who put a bounty on a question that is obviously off-topic here and imho against the spirit of the site's response to coronavirus misinformation, drawing attention to it and, I understand, ensuring that it cannot be closed for a week. $\endgroup$ – David Apr 11 '20 at 10:41

In fact there are many RNA viruses and there is no reason they can't have a vaccine. In fact the flu we get every year is a good example. Influenzas are RNA viruses with a new vaccine coming out every year.

Vaccines sometimes don't even have the RNA/DNA of the organism you are trying to immunize against. (I'm just going to talk about viral vaccines - there are many other related topics). Immune response is typically targeted to proteins on the external surface of the virus. Antibodies to these proteins are not only effective in creating an immune reaction, but also are ideally protective; some antibodies will block the virus from infecting and help actively fighting the disease. That's a double win and a big reason why previously infected individuals might become immune to a disease: the antibodies in the blood are stopping the virus from acting on contact. There are no technical barriers to a vaccine.

So why don't we have a vaccine? There are literally millions of families of viruses and its not cheap to develop a vaccine and that money means nothing if the public don't accept vaccination. While SARS and MERS were a strong indicator that Coronaviruses would be a threat, in themselves they turned out to be easy enough to stop without bringing the global healthcare apparatus to bear.

Even if they did develop one, its not clear that a SARS or MERS vaccine would be effective against other cornona viruses. Even though the flu is from the same species of virus, we need a new one every year to react to how quickly it changes.

If there had been a corona vaccine available... lmk ask you a question... The MERS outbreak was 2012. The public, having lost awareness of the benefits of vaccines, are not big on seeing the value of paying even $10 for a shot and then not getting sick. You never knew it did you any good. Would you have taken one last fall? Every year for the past 5 years?


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