Understanding SARS-Cov-2, Effects of Covid-19 and the Future

[Astronuc]

The original article from Statnews, "Covid hasn’t given up all its secrets. Here are 6 mysteries experts hope to unravel" didn't sound right. SARS-Cov-2 is the virus, Covid-19 (Covid) is the illness (Coronavirus disease) or set of symptoms caused by the virus.
https://www.statnews.com/2022/04/19/six-covid-mysteries-including-how-it-will-evolve/

Outstanding questions:

1. How will the virus evolve next?​

2. What will future waves look like?​

3. If you’ve never had Covid, how worried should you be right now?​

4. How, exactly, does the virus transmit from person to person?​

5. Will we get a new, better generation of vaccines, therapeutics, and tests?​

6. How long before we understand long Covid?​

. . . more than two years after SARS-CoV-2 appeared, as documented deaths in the U.S. near 1 million and estimated global deaths reach as high as 18 million, there are still many mysteries about the virus and the pandemic it caused. They range from the technical — what role do autoantibodies play in long Covid? Can a pan-coronavirus vaccine actually be developed? — to the philosophical, such as how can we rebuild trust in our institutions and each other? Debate still festers, too, over the virus’s origins, despite recent studies adding evidence that it spilled over from wildlife.

Some of these questions defy answers entirely or can only be resolved over time. Here, STAT examines six mysteries that scientists are beginning to unravel. The eventual answers will determine our relationship with Covid and and how we’ll fight a future pandemic.

I've heard comments recently that everyone has been exposed, or has had Covid, or will get Covid. My wife and I have so far tested negative, but then we haven't been tested recently, since my son was exposed and did become ill (probably Omicron). It's not clear that he hasn't experienced long-term effects. Even if one doesn't become extremely ill, we don't know for everyone what the long term effects will be. One of friends developed Covid-19 from exposure at work. He got pretty ill, but recovered over a week thanks to some anti-viral medication (I believe molnupiravir).
https://www.nejm.org/doi/full/10.1056/NEJMoa2116044

Remember the pandemic’s early months of ceaseless surface-sanitizing and hand-scouring? It’s now clear that contaminated surfaces are rarely, if ever, the culprit. Rather, SARS-CoV-2 is primarily transmitted through the streams of mostly invisible respiratory particles that everyone emits when they’re talking, singing, sneezing, coughing, and breathing. It can survive in even the tiniest particles, called aerosols, which can linger in still indoor air for hours and be inhaled into the deepest recesses of one’s lungs.

I thought it was clear in January 2020 that it was transmitted by respiratory particles. Hence, the effectiveness of masks (e.g., N95 or KN95), and face coverings, in reducing transmission.

In March 2020, Munster and his team provided some of the first evidence that SARS-CoV-2 could stay suspended in the air for hours. Later, they showed that these aerosols more easily infected hamsters and made them sicker than virus the animals picked up from surfaces. In a study published in January, his team proved for the first time that the smallest aerosols — those less than 5 microns — contain enough virus to infect other animals at distances up to 6 feet after just one hour.

How long before we understand Long Covid?

Scientists from many disciplines are tackling the collection of symptoms that persist in as many as one-third of people after a Covid-19 infection. Virologists are turning their HIV expertise to this coronavirus, neurologists are trying to explain the cognitive and physical disruptions they see in rehab clinics, and immunologists are teasing out inflammatory and autoimmune responses.

 

[morrobay]

3. If you have never had covid, how worried should you be right now? Well if you are overweight with related diabetes and hypertension then get vaccinated. If you have BMI 70kg/1.81^2 of 21.4 and O neg. And furthermore have not had the flu or a flu shot in 25 years. Not worried at all. I am unvaccinated for SARS-Cov-2. However I'm sure I've been exposed. Especially walking through this crowded market a few times a week for past years. Some are exposed but not infected : Cross reactive T cell immunity from exposures to the other four circulating coronaviruses .

 

[pinball1970]

3. If you have never had covid, how worried should you be right now? Well if you are overweight with related diabetes and hypertension then get vaccinated. If you have BMI 70kg/1.81^2 of 21.4 and O neg. And furthermore have not had the flu or a flu shot in 25 years. Not worried at all. I am unvaccinated for SARS-Cov-2. However I'm sure I've been exposed. Especially walking through this crowded market a few times a week for past years. Some are exposed but not infected : Cross reactive T cell immunity from exposures to the other four circulating coronaviruses .View attachment 300687View attachment 300688

https://www.walesonline.co.uk/news/health/super-fit-dad-one-46-19728049

 

[jim mcnamara]

@morrobay - Have you had a serological test? I cannot tell. Why am I asking? Because it is extremely unlikely that you have not been exposed to the Covid virus and then had an asymptomatic case. A serologic test can usually discern if you have antibodies to that virus due to infection.

This is a BIG problem - because people wander around thinking they have never had the disease and then cite themselves as some a sort of anecdotal evidence against vaccination.

The only way you can refute my claim is with a blood test like I described. Just because you feel 'great' is not scientific evidence at all.

This discusses the misuse of antigen tests, which in a sense you are doing. In reverse.
https://www.fda.gov/medical-devices...mmunity-after-covid-19-vaccination-fda-safety

FYI there are multiple case reports of people who have had positive PCR tests over a time span, showing reinfections are very possible. So you are not immune to further infections in the future. Asymptomatic or otherwise.

Physics forums does not need this kind of misinformation. Please stop.Reinfections, CDC mmwr:
https://www.cdc.gov/mmwr/volumes/71/wr/mm7114a2.htm

 

[morrobay]

@morrobay - Have you had a serological test? I cannot tell. Why am I asking? Because it is extremely unlikely that you have not been exposed to the Covid virus and then had an asymptomatic case. A serologic test can usually discern if you have antibodies to that virus due to infection.

Several places in this paper, results, discussion you will find: Overall our results indicate that person's exposed to SARS-Cov-2 may develop specific T cell response without detectable circulating antibodies, seroconversion . This is not one and same as Covid asymptomatic. This is what my previous post stated. That I assume I have been exposed however the T cells cleared the virus before infection. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7774579/.

 

[morrobay]

<50 negative .>=50 positive . Interpretation?

 

[morrobay]

https://www.imperial.ac.uk/news/233018/cells-from-common-colds-cross-protect-against/

 

[Astronuc]

By now, you may know—or be—someone who has had COVID-19 two, three, or even four times. Omicron and its subvariants, which are highly contagious and contain mutations that may allow them to evade the body’s vaccine- and infection-acquired immune defenses, have made reinfections an unfortunate but common part of life.

https://time.com/6196814/covid-19-reinfections-omicron-risks/

The risks might be low for many under 60+, but risks increase with age, and the damage due to recurrent infections, or reinfections, is cumulative, as they are with influenza/pneumonia.

A new dominant omicron strain in the U.S. is driving up cases — and reinfections​

 

[pinball1970]

https://time.com/6196814/covid-19-reinfections-omicron-risks/

The risks might be low for many under 60+, but risks increase with age, and the damage due to recurrent infections, or reinfections, is cumulative, as they are with influenza/pneumonia.

A new dominant omicron strain in the U.S. is driving up cases — and reinfections​

UK Cases in hospital have risen from 5,000 to 15000 in a month or so. Deaths are around 60 per day at the moment.
I will check the latest technical briefing from UKHSA, see if they are publishing information on the variants.

 

[pinball1970]

latest on variants from the UK

https://assets.publishing.service.g...le/1086494/Technical-Briefing-43-28.06.22.pdf

"BA.4 and BA.5 Growth BA.4 and BA.5 were designated Variants of Concern (VOC) on 18 May 2022 based on a growth advantage which could plausibly lead to increased community transmission. BA.4 and BA.5 are now dominant and COVID-19 incidence is increasing. Updated modelling shows that BA.4 and BA.5 continue to demonstrate a growth advantage over BA.2 with a relatively high degree of certainty. The relative growth advantage for BA.5 is larger than BA.4 and it is therefore most likely that BA.5 will become the dominant variant in the UK. We estimate that 22.28% (CI: 16.25 to 28.77) and 39.46% (CI: 32.19 to 51.31) of cases are currently BA.4 and BA.5, respectively"

page 11 shows the variants rise and fall from Feb 2021

 

[Laroxe]

I wonder what the mystery actually is. We have in fact known for some time that predicting the future is difficult even for those with crystal balls of the highest quality. That seems to be the basic “thrust” of the article, but really some of these issues have been around since before Covid 19 appeared. The first two points will become clearer with little effort, we simply have to wait for the future to arrive. Then there is the issue of
how worried we should you be? Well, its already clear that there are considerable variations in the effects of exposure to the virus, often related to the type and length of exposure. Many people who have been exposed but who never develop symptoms tend to develop rather limited immune responses, once the virus is controlled the immune system stops refining its responses. Even following a robust response, one we have the most information about, humoral antibodies, are very short lived and offer limited protection against infection. Really, worry should be focussed on the risk factors that have the biggest effect on survival, most of which have an effect on immune competence, with advanced age being the most significant. If your over 80, worry may be appropriate but of course people at this age generally behave in ways that reduce the chances of exposure.

Then there is transmission, which appears to be similar to other respiratory viruses, rather than mysterious. The asymmetric spread we see, which is associated with individual differences in viral shedding isn't well understood and in fact wasn't before Covid appeared, other viruses are known to spread in the same way. We know that the possibility of infection varies with the route of exposure, but with Covid, the public information we developed was based on the evolving evidence available. We now have some reasonable estimates of the effects of the route of exposure but this is unlikely to get more precise despite complaints about the uncertainty. There are simply to many variables effecting viron survival in the environment and route of exposure for any sort of precision.

We know that vaccines offer little protection against infection, but this wasn't what they were developed to do, the vaccines were judged based on their ability to prevent serious disease and death. Currently many of the vaccines, following a full course of immunisation, are associated with around 95% protection against these outcomes. The short lived antibody responses and immune avoidance mean, its unlikely that any new vaccines will offer better protection against infection, but the 95% protection against serious disease is impressive and better than many other vaccines. Improvements in these outcomes, with new vaccines are unlikely to be dramatic, the current aim is in generating more enduring immunity and a broader range of antibody targets. The timing and the effects of different vaccine mixes still needs to be refined and it may be possible to develop vaccines that protect against other Coronavirus infections, the evidence from studies of cross immunity isn't really that promising.
I think the biggest impact of long Covid has been on people suffering from ME and Chronic fatigue syndromes, conditions, dismissed by the medical community for years. A considerable amount of prior research being used in an attempt to confirm these conditions as psychogenic and unworthy of serious consideration. As long Covid has become a major issue, this attitude has blown up in the medical communities face, with much of the past research exposed as worthless. This does mean that with long Covid we are starting basically from scratch, medical bias, effectively prevented progress. There are still patient groups who are deeply cynical and angry and a great deal of pressure and blame has been attached to the medical community. The large numbers now being seen with long Covid does mean that this has become a major political issue as health services attempt to meet demand with few available tools to help. So far, research has focussed on using vaccines and treatments against Covid in an attempt to prevent long Covid. While this does seem to have some effect, advances really require developing an understanding of parts of the immune system, that have until now attracted little attention. The same issue has caused significant delays in understanding Covid immunity, even limiting the tools we have to study parts of this system.

This does provide a prime example of how arrogance in dismissing patients, as none expert and the resulting biases, can effectively destroy objectivity. The huge amount of money devoted to Covid research has in fact brought significant changes in our understanding of disease and the development of effective vaccines quickly, a huge achievement. Unfortunately this has also been associated with increasing levels of people refusing infection control advice and vaccine refusal, the common coercive responses and insults to people, being the worst possible way of trying to control this. Oh well, rant over.!