US: 81,000 new cases yesterday. 1,000 deaths.
228,000 deaths in total.
Let's play " Ask a Scientist "".
Mr Crow: What's the future for the US and Covid19?
( As a layman, I see a very dark future.)
When I first started looking at the mortality rates with outbreaks occurring in Western Countries with modern Health Systems that were not overwhelmed at the time, it appeared to me that the overall final death rate would be about 0.7%. That is, when all was said and done COVID-19 would be about 5x more lethal than the annual flu. From memory I did this cursory analysis in Feb-March and it included no data from China.
We would have to crystal ball gaze to see what the possibilities are from here. That involves some knowns, assumptions and unknowns.
We now know that a reasonable percentage of the infected can transmit asymptomatically or presymtomatically. This makes Covid more dangerous than SARS.
Airborne transmission seems a major route of infection.
It is possible that the viral load at exposure is a determinant of severity of infection. This is common for all microbial pathogens. There is a threshold for each individual above which you succumb relating to your innate immune system. As this is novel virus to humans we have to rely on this component when initial exposure occurs. This point needs to be considered for effective mask wearing.
It appears that immunity will be long lasting. There were fears that it might be transient and people could get reinfected. It looks now that it is likely to be years.
The virus needs humans to multiply so that it is dependent on human socialisation/interaction behaviours entirely. Sweden is often sited as a country that did not impose strict lockdowns but the general population generally altered their behaviours voluntarily. Their travel patterns decreased significantly.
The biggest unknown from my perspective is the possibility of long term health effects on those who recover. It appears to be significant on some but unfortunately only time can tell.
No Vaccine, or poor uptake of vaccine.
Herd immunity without an effective vaccine is not an option. Anyone can do the math on that. You could attempt it by deliberately exposing all of the "low risk" group over a short period, even if felt desirable this would be medically unethical. I haven’t checked the population range in the USA but unless the low risk group represents well over 80% this method would not result in the desired effect and the virus would always remain in the population ready to infect the vulnerable. The Spanish (really American) Flu went around the world a couple of times, killing millions but eventually mutated and became part of the seasonal flu population. There was no vaccine to it. They did not even know it was a virus at the time. So for latest virus we would be relying on a mutation that made the virus less lethal in the absence of an effective vaccine (or therapeutics).
Vaccine
There is optimism of the development of at least one effective vaccine. At this stage it would seem at least six months away. The testing needs to be finalised, that is it is safe and effective in preventing infection for the vast majority.
It will required upscaling in production and distribution. It also required uptake by the population. This might be the biggest problem currently with adoption of a vaccine.
I also agree that strict lockdowns can only be effective for a limited time. Humans are naturally social and there are huge economic implications to this also. The trick is getting the mix best we can.
To John’s question for the USA, let’s assume Biden wins. Trump is in power until January.
With no vaccine (or poor uptake), all you really have is long term behaviour alteration as defence. The old team, hand washing, social distancing and masks etc. that’s a tough haul. If you talk about deaths, it seems to be around 1000 per day at present. It does not seem to be going up with the case rate as it did initially, so let’s all hope it doesn’t.
Let’s assume that even after the election result there is not much behavioural change regards to the virus. At 1,000 deaths per day that would be another 80,000 deaths, for a total of more than 300,000. That would be my best guess at present. Cases is harder to predict, the category to fear is hospitalisations. The last thing the USA needs is a hospital system swamped over the Christmas New Year period.
After Biden takes office I would expect to see little meaningful change in rates until the vaccine is available. Let’s hope that confidence in science is restored enough so that the general population will willingly be vaccinated for the good of all.