I'd like to ask you a question about a possible vaccine. COVID-19 is a single stranded RNA virus. From what I understand that would mean that it's more prone to genetic change than a double stranded DNA virus would be.
So...if Dr. Moore and his team is successful how would the vaccine work?
Does the virus mutate so much that we'd need a new vaccine each year as we do for the flu?
Or would it be like the vaccine for small pox? We could be vaccinated and not ever get infected with COVID-19 again?
Is it possible to answer this yet?
Thanks for your time...
Good question!!! I can't overstate how happy your question makes me; it means that non-scientists are asking the right things. Most of the questions I've received on the subject are depressingly naive and/or rascist.
You're correct, the virus SARS-CoV-2 (which causes the disease COVID-19) is a single positive stranded RNA betacoronavirus. In generality, single stranded RNA (ssRNA) is less "stable" than double stranded DNA (dsDNA). As such, ssRNA genomes are often much shorter and more prone to mutation compared to larger dsDNA viruses. For example, HIV-1 (a ssRNA retrovirus) mutates so quickly that each infected person usually has dozens and dozens of unique sequence isolates in their body at any time. As you suggested, this means it can mutate around the many drugs we have invented and has prevented us from making a functional vaccine.
However, SARS-CoV-2 does not appear to mutate that quickly. In fact, of the hundreds of sequences that have been gathered to date, VERY few point mutations exist. Furthermore, betacoronaviruses have some of the longest ssRNA viral genomes. Together, this suggests that the "mutational sequence space" available must be limited. In other words, in contrast to HIV-1, SARS-CoV-2 is able to replicate with much higher fidelity, most likely because its own RNA polymerase is very very efficient. So, in terms of treatment/vaccine, this may help us. If it is slowly mutating, then our vaccines will be less likely to fail. HOWEVER, I promise you that it will mutate in the future; that is an inevitability.
The longer answer is that it very much depends on how the vaccine works. For a hundred years, the way vaccines were made was to deactivate or weaken a virus and give it to a person. This allowed the immune system to do what it does best; sample the virus and develop a semi-permanent resistance to infection without the burden of actually getting sick.
However, viruses often have evolved ways to "hide" from the immune system. For example, influenza mutates rapidly which why there are a near infinite number of versions. But a big reason why vaccines are only partly effective is because the immune system often targets the easiest part of the virus to target. The virus leaves this "low hanging fruit" while assuring that it mutates this part of its genome the most rapidly which leaving the parts that can't mutate "protected".
But we are getting smarter. Instead of just weakening viruses and letting the immune system figure it out, we are trying to take the guesswork out of the equation by telling the immune system what to target. I don't know the specifics, but Melissa Moore's team is working towards this concept as well. So I would argue that it is more likely that the vaccine strategies developed for SARS-CoV-2 (if they work) will likely permanently effective for SARS-CoV-2. But they probably won't be effective for the inevitable SARS-CoV-3/4/5/... But as we get better and better at identifying, isolating, and rapidly sequencing, we will also get better and better at developing treatments and vaccines as fast as the virus mutates.
Sorry for the length! I actually had this post 3-4 times as long and tried to cut it down as much as I could stand
Please don't hesitate to ask more though!!
There are cases in Tenerife, Barcelona, Austria, Switzerland, Croatia and Sicily.
I highly recommend Dr John Campbell's YT channel I linked to earlier.
He is respectable enough to have been interviewed as a specialist by DW (the German version of the BBC World Service).
The US CDC has said that it is not a question if but when Covid 19 reaches the US mainland. Hopefully it will be later rather than sooner because I can't see Americans to be as accepting of lock downs as the Chinese population.
The earliest the vaccine will be available apparently is Spring 2021.
John Campbell is no dummy. He might not be an immunologist persay, but he has plenty of experience in infectious disease research. Not a bad source of info.
So far, doctors (and other medical professionals) have done an exemplary job identifying those infected and keeping track of the epidemiology. The big problem will occur when the virus reaches developing/semi-developed nations where organized healthcare is minimal. They will have no way to test for the SARS-CoV-2 specifically (PCR as you were forcibly taught) and even less ability to enact quarantine procedures. Once that happens, limitation of spread will be, more or less, impossible. In fact, it is entirely possible it has already occurred and we have no idea. That's why the former CDC director Dr. Tom Frieden says that pandemic spread to the US is inevitable.
Also, I feel the need to give a word of warning. The current CDC head, Dr. Robert Redfield, while overpaid and with questionable motives, seems to know what he's talking about. I've met Bob and he has a good head on his shoulders and can manage people. However, he takes his orders from his boss, Alex Azar, the Secretary of Health and Human Services. Alex is a hopelessly incompetent man who knows just enough to sell a drug, but nothing else. I've haven't spoken directly with him, but I've heard him speak at multiple meetings specifically about government response to viral epidemics (in terms of influenza). It was immediately clear that he did not know what he was talking about. Mark my words, if the virus hits the US hard, the situation will be poorly handled and people will suffer.
So far, doctors (and other medical professionals) have done an exemplary job identifying those infected and keeping track of the epidemiology. The big problem will occur when the virus reaches developing/semi-developed nations where organized healthcare is minimal. They will have no way to test for the SARS-CoV-2 specifically (PCR as you were forcibly taught
) and even less ability to enact quarantine procedures. Once that happens, limitation of spread will be, more or less, impossible. In fact, it is entirely possible it has already occurred and we have no idea. That's why the former CDC director Dr. Tom Frieden says that pandemic spread to the US is inevitable. Also, I feel the need to give a word of warning. The current CDC head, Dr. Robert Redfield, while overpaid and with questionable motives, seems to know what he's talking about. I've met Bob and he has a good head on his shoulders and can manage people. However, he takes his orders from his boss, Alex Azar, the Secretary of Health and Human Services. Alex is a hopelessly incompetent man who knows just enough to sell a drug, but nothing else. I've haven't spoken directly with him, but I've heard him speak at multiple meetings specifically about government response to viral epidemics (in terms of influenza). It was immediately clear that he did not know what he was talking about. Mark my words, if the virus hits the US hard, the situation will be poorly handled and people will suffer.
We now have patient 1 in the USA who has no record of contact with anyone who has traveled from the East. The implication is that an intermediary who has been in contact with someone who traveled from the East was a symptomless carrier. If this is the case, we now have CoVid-19 in the general public and will see a general outbreak within two weeks.
I have seen indicators that at least one of our factories may start running out of parts within two weeks. IF this happens, then the supply chain is indeed impacted.
I have seen indicators that at least one of our factories may start running out of parts within two weeks. IF this happens, then the supply chain is indeed impacted.
My apologies, do you mean how the virus initially infected humans?
If so, the answer is, we don't fully know yet. Early reports from researchers in China argued that the source could be a Pangolin, a scaly, ant-eating animal commonly sold in illegal markets in China. However, further sequence analysis suggests otherwise.
Mystery deepens over animal source of coronavirus
Basically, we are gathering samples from animals either living near or sold directly in China's markets. From these samples we are using PCR and genetic sequencing to test for the presence of SARS-CoV-2/COVID-19 (or for a virus very close to it). Although the initially tested region (the RNA binding domain) of the pangolin virus was 99% identical to the SARS-CoV-2, the rest of the pangolin virus is only about 90% identical. This is definitely not close enough to say that the virus spread directly from butchering Pangolins.
For comparison, the SARS outbreak of 2002 is thought to have originated in Civets, a small, cat-like animal. The genetic sequence of the virus isolated in Civets was found to be 99.8% identical to SARS. We have not yet found any animal or sample with a virus that close to the current outbreak. As such, we do not yet know what animal was originally harboring the virus.
I've been actively following the outbreak (and most other outbreaks) since the start. Maybe I read different sources, but what legitimate news source said that it was bat soup?
Bats are a prime candidate for initial zoonosis, just ask anyone on the Ebola and Marburg teams. If we were doing round robin betting, my money is on bats. However, unless the sequencing comes back near 100% identical, I wouldn't argue anything.
A sub-url link from that article is on https://www.biorxiv.org/content/10.1101/2020.01.29.925867v1.full.pdf
, nice because Did not know there was a 'bio' axriv.
One of my hobbies is bio-quantum-entanglement.
, nice because Did not know there was a 'bio' axriv.
One of my hobbies is bio-quantum-entanglement.
Yeah, BioRxiv is a relatively new thing. I'm a HUGE proponent of it and have several papers on there. Take back science from Science, Nature, Cell, etc!
Haha I said media, not necessarily a reliable source of anything.
In this case UK tabloids reporting on something about some odd accusation regarding bat soup and that being responsible for the ease with which the virus hopped species.
This was right at the outset and only a small story in a tabloid, probably coming from some website or other, spreading the belief as theory.
It probably stems from somebody knowing just enough about virology to describe Ebola originating in bats if, as you say, Ebola originated in bats. I know I absolutely zero about this kind of thing.
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I read that this morning and didn't think more of it until now. Why is this? Do people think you can get the virus from Corona beer?
Are uber drivers going to avoid little Italy too? Ignorance breeds ignorance
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