Blog/COVID19 post draft

COVID19 post draft You can go down to very low levels of COVID19 like one new case per million per day or less by public health measures of test, trace,isolate, quarantine, active surveillance, promptly reacting to any outbreak by testing everyone especially if you also test people who don't have symptoms yet - and for the general public, physical distancing, not touching eyes nose or mouth without washing hands thoroughly, avoiding crowded places with poor ventilation or making sure there is adequate ventilation indoors - and wearing a cloth mask to protect others if you need to be closer than 1 meter when talking, singing, laughing, coughing etc.

We can make the disease less severe in its effects with better treatment methods and therapeutics. Many being tested, and two have proven effects already, remdesivir to reduce the time in hospital by a few days, and dexamethasone reduces mortality for those on oxygen significantly (but actually probably makes things worse if you don't need oxygen).

There are several others that are very promising in small scale trials but they are not double blind and could be statistical anomalies so they have to be tested properly before they can be recommended.

On vaccines, then there are 23 in clinical trials, two of them in stage 3, one from Oxford particularly promising as it is based on an adenovirus which hopefully will confer longer lasting immunity than a coronavirus based vaccine, and one from China which is an inactivated virus vaccine.

It is very common for vaccines to fail at stage 3, so there is no guarantee - they might not protect at all. But we will soon know, within a few weeks because of large numbers of volunteers in areas wth outbreaks - the Oxford one is being tested in Brazil since the number of cases is too low now in the UK to get results quickly.

We will know when they get to the point of about a dozen or so infected out of several thousand vaccinated. If most of those are in the control group then it is protecting at least to some degree, while if they are equally between the vaccine and control group then it doesn't offer any protection. It could also conceivably make it worse, in which case there would be more infections in the vaccinated group.

If you do get it when vaccinated then they will want to know how the disease progresses. For instance some vaccines don't stop you getting it but they stop you from displaying the symptoms and so basically stop you getting the clinical disease but you can still pass it on to others.

If it is like that then it is still useful of course, especially for high risk people, vaccinated so that when you get the virus you don't get sick, but we'd need to look further for a vaccine to stop the disease.

With 23 in clinical trials, and 140 that are in preclinical trials in animals then it seems pretty certain really that we get one eventually - and those 23 - they should go through to phase 3 in a few months and then another few weeks to a month or two to complete phase 3, longer if the world has suppressed the virus to the extent that there are no more major outbreaks left - but if there continue to be major outbreaks theno by the end of this year or early 2021 we should have some idea whether any of those 23 are safe and effective. If not, we have the remaining 140 some at least bound to reach clinical trial status and more new ones being added all the time.

Once any vaccine is proven to work there are manufacturers around the world can produce them in hundreds of milions and eventually billions. Also it is impossible for any country to sit on a vaccine and not license it to these manufacturers because under WTO rules then in an emergency like a pandemic a country can issue itself a compulsory license to something essential like a vaccine or a therapeutic even if the patent holder doesn't grant them a license (they have to pay them a reasonable recompense that they decide for themselves). For countries with weak health systems - Bangladesh has already granted itself a compulsory license for Remdesivir that has no royalty payments - they can do that because they are a developing economy.

However the vaccine developers already say they will license it royalty free to countries with weaker health care systems. The WHO is strongly behind making sure all vaccines are available to anyone who needs them and also they have the distribution networks too to make sure everyone gets it. It will be a massive task, there are several other diseases we could eradicate from the world like measles as we already have a safe and effective vaccine, but there is the political will and fInance to eradicate COVID19. So I think we will do this.

The WHO already coordinated eliminating smallpox from the world and eliminating measles, rubella, and polio from the Americas. There is no reason why we couldn't eliminate those other three diseases from the whole world and when this outbreak started, the WHO were close to the point of eliminating polio from the world too, within a few years of that.

Suppressing it, any country can get down to less than one case per day per million - that would be 300 a day for the whole US.

If all countries could do this then we would eradicate it just by public health measures since those extra cases those 1 per million would be imported cases. Isolated countries like New Zealand can eradicate it completely. Bhutan, similarly isolated by mountains surrounding it, has kept the virus out of its country by quarantine (it has a longer quarantine period of 21 days to be extra sure). North Korea claims to have kept it out by closing its borders, which is possible but hard to verify. Guernsey island near the UK has eliminated it by these public health measures and quarantine.

So - it can be eliminated. Theoretically it might linger in people perhaps in their stomach (where it can theoretically linger at a low level) and resurge months later, but so far the new outbreaks in China and New Zealand are from hard to trace imported cases and there is no evidence yet of new outbreaks from resurging infections in someone already infected months earlier.

So - if we really all did the physical distancing, test, trace, isolate etc thoroughly for a few weeks it would probably soon be gone from the world apart from any severe cases still in hospital and once those all recovered it would be extinct.

The resurgence in the US is because of people not doing the physical distancing, the governers lifting lockdown too soon without test, trace, isolate in place and not communicating clearly how important the physical distancing etc is for a few more weeks after lockdown to keep it trending down until it is close to over.

Probably by the end of this year we will be hearing the results of the trials every few weeks.

If the Oxford vaccine is a success then the first vaccinations would be this september or october - but would take some months to scale it up to vaccinate everyone.

The Oxford vaccine has production capacity lined up for 2 billion vaccines by early 2021 and several hundred million this year. But if it was a success many other manufacturers would join int.

Yes NATURAL herd immunity may be short lived. Nobody knows. Coronavirus colds can reinfect within a year and sometimes within a few weeks but MERS and SARS may have immunity lasting a year or two. However VACCINES are designed to trigger a stronger immune response. They give a big dose right away to stimulate your immune system and the dose is designed to trigger the best antibodies, that last longest.

The Oxford one is based on an adenovirus which causes a different kind of immune response from a coronavirus and hopefully will make the immunity longer lasting. That is the idea behind vaccine design, they design the vaccines to trigger a strong effective immune reaction.

The phase III trials are to test to see if that design worked. Phase I and II test for safety - but also test to see if it is stimulating antibodies so by phase III you have reasonable indications it might work and then test it to see if it really does. We have two vaccines already in phase III one in China and the Oxford one. The Oxford one is well ahead because they made it for MERS and it was at a very advanced stage already.

Many of these vaccines were developed for SARS or MERS which saved years of development time, Oxford just happened to be the fastest off the block. It's like wondering why someone won a 100 meter sprint - someone has to be first. It may be the better sprinter or it may just be they had a good day.

Another one from China an inactivated virus vaccine is also in phase III and not far behind. We should start getting results in a few weeks - probably Oxford first and then there are so many other vaccine candidates we likely get new results every few weeks after that learning from one vaccine after another, and hopefully soon one of them is the one we want. If not, with 23 in clinical trials and 140 following in preclinical animal trials we can expect results from more and more vaccines, by early next year likely getting results from one vaccine after another maybe even most weeks.

That is if we still have big outbreaks. If the virus is nearly all controlled by then, suppressed worldwide it will be harder to get the results.

There there's an idea called a "human challenge" trial where healthy young volunteers are deliberately infected with COVID19 to see if the vaccine protects them. That gets results a bit faster and much faster if there isn't a major outbreak to test it on. But it risks some of them dying, not a big risk if you have a dozen or so and they are young had healthy - but still may happen.That would be easier to do once we have better therapeutics which reduce the mortality.

There are many volunteers have already signed up for human challenge trials so there would be no trouble getting volunteers, but there are questions about the ethics, I think it will probably happen if we do get to that point and there aren't enough cases in major outbreaks to test it that way. It's not unheard of, have been previous examples of volunteers deliberately getting infected with disease to test vaccines. But normally there is some treatment for the disease so having good therapeutics will help to make this more feasible.