Covid-19 and Understanding its spread

The diagram above is called the disease triangle. For Covid-19, the pathogen is the virus, and the host is humans or the body’s organs susceptible to the disease. We know now it is not strictly a respiratory problem. Environment can be considered the conditions by which transmission is possible or likely. When Covid began, there was an immediate need to know how Covid invades the body and replicates. Thus, the Host – Pathogen axis was critical. Equally important was knowledge of under what conditions the disease could spread, thus Pathogen – Environment axis became important. Large gatherings of people in airports, bus and train stations, and for events, such as sporting or musical events were obvious venues for disease dispersion.

Many would include a fourth element, which would be “Human Response.” I think the fourth vertex is critical in Covid. The medical response is to find ways to interfere with a disease’s growth and spread, through effective treatments and vaccines. The Covid susceptibility is much lower in countries where there is a high level of vaccination. I believe easy access to testing and rapid results allows individuals to self quarantine and seek medical assistance.

The pathogen is not constant. The delta variant spread globally with lightening speed, and the downward trend in new cases has been reversed, with increases in many countries including the US. The understanding of the infection process is still evolving with the long term damage, termed “long Covid.”

There is a commonality in the global deadly viruses, which is asymptomatic characteristic of the disease and ease of transmission. A healthy person can be a carrier of the Covid even though there are no obvious symptoms. They are unlikely to be tested in this early phase of the disease. Covid can be transmitted either directly from someone else or from touching surfaces.

The human response has a sociality aspect as mass vaccinations need cooperation. The negative aspect is clear: vaccination hesitancy, resistance and ignorance. Misinformation via social media and politics are playing negative roles. The Trump and Biden administrations are to be commended for an incredibly rapid and effective roll out of vaccines. See former Secretary of HHS, Alex Azar comments on vaccines in links.

The human response should mean we act together in accepting restrictions, including indoor mask wearing, as it is now both a necessity and temporary. Further, we need to recognize this as a pandemic and help countries which can not afford vaccines for their populations. Otherwise, the disease will continue to re-appear in the US. We don’t know how long the immunizations will last for or what new variants might appear in the future. So, we can’t accept just reducing the new cases to a low level in the US.

We have to accept the new medical information, which is the Delta variant is spreading and new cases are on the rise. It is not as dramatic, but the cases of people in the US dying of Covid have also been rising in the last 30 days.

Stay tuned,

Dave

I Was the Architect of Operation Warp Speed. I Have a Message for All Americans. by Alex Azar

Why You Should Get Vaccinated

Covid-19 is a worldwide killer and vaccines are the answer, if everyone does their part. Let me tell you why.

The Covid-19 vaccination program began in December 2020 with Pfizer and Moderna vaccines. The supply was very scarce and the demand was very great. There are a lot of people in great health who have died of Covid-19. They ate well, took care of themselves and have no idea where they got the virus. Frontline medical professionals have died from Covid-19. In some cases, their immune system went into overdrive, and they didn’t pull through.

I’ve heard plenty of people feeling the after effects of Covid-19, including weeks without being able to taste food and respiratory problems.

Worldwide we just past the 1 billion doses of vaccines being administered. We still have a long ways to go. In the US and other countries, health professionals are monitoring the effectiveness of the vaccine. They don’t work for the drug companies. They have found that the vaccines are working, even against the various new strains. However, for the 2 shot vaccines, the second shot is really necessary to get the full benefit of the vaccine.

I’ve heard now, a few reasons why not to get vaccinated. The first is that it might actually cause you to get coronavirus, as they are injecting a weaken virus into your system. This is totally false. They are injecting strands of DNA which generate anti-body cells to defend the body against Covid. Second, the vaccines are not 100% effective. This one is true, but I’d say, 95% effective is pretty good to me. There will never be a perfect vaccine.

I heard a commentator state that the elderly are dying from Covid and the youth are spreading it. Well, yes and no. A third of the elderly population is unvaccinated, and they certainly can be spreading it. And within the US, there are 2,300 young adults (under age of 30) who died of Covid-19. It is sad, but now it is also preventable.

Covid-19 is a worldwide killer and vaccines are the answer, if everyone does their part. End of sermon.

Stay tuned,

Dave

Press Briefing with Dr. Fauci

Covid-19, Brazil and the World

In Brazil, the daily deaths due to Covid-19 made an all time record, of 2,286 on March 10, 2021.  These are people who did not make it out of the hospital.  This is four times as many people as four month ago.  This is real and it is scary.      Brazilian hospitals are overrun with new cases.  When hospitals run short of equipment such as ventilators,  more people die.

Deaths from Covid-19 in the world are trending down.  Only  about 1%  of the world is fully vaccinated.   The US is far head with 10% fully vaccinated.  Brazil has fully vaccinated only 1.4%. of its 211 million residents.   Note that reports of a 4% level of vaccination for Brazil is based on “one or more” vaccinations rather than the required two shots.

The progress in the world is likely a combination of vaccines plus stricter restrictions on travel and social gatherings in clubs, bars, restaurants, weddings, church sermons and  family re-unions.  Enforcement of mask wearing rules and social distancing I am certain helped reduce Covid-19 worldwide.

Brazil is going the wrong way in general, with the new record high.  I predict by May, they will be averaging 2500 daily deaths, with fewer than 5% of the population fully vaccinated.  Brazil accounts for 18% of all deaths from Covid-19 worldwide and may climb to 40% by May, 2021 (2500 in Brazil verses 6000 worldwide).

There is competition in the purchase of vaccines.  Brazil is now looking at ways to increase the supply of vaccines from China (see links below), while three months ago, it was hostile to the idea of testing of Chinese vaccines in Brazil in return for additional supplies. The efficacy of Sinovac vaccine (Coronavac) was reported to be only 50%, but it was 70% in preventing moderate to severe cases, which is very good.   The severe cases can result in death, particularly among my group (older males).    From everything I’ve read, Brazilians are ready to take the vaccine, but the supply is extremely limited.

Because vaccines are never 100% effective, the wearing of masks and social distancing are still required.  As long as there is a high rate of new infections, restrictions must stay in effect.   Biden last night delivered a powerful speech, in asking the American public to take precautionary measures to prevent a new surge in new infections.  Brazil needs to look on how it can best reverse course.

We will get rid of Covid-19 only by everyone’s action in every country in the world.  There is no magic pill.

Stay tuned,

Dave

Links:

https://www.reuters.com/article/us-health-coronavirus-brazil-vaccine-idUSKBN2B21Y8

https://ourworldindata.org/grapher/biweekly-covid-deaths

(The bi-weekly data chart helps smooth out the data noise).

https://www.bbc.com/news/world-latin-america-56342303