How can the Coronavirus pandemic end?

As we struggle to re-open our economic and social fabric in the United States we wonder how will the pandemic end?

There are two ways it can end.

1. Herd Immunity (also called herd effect, community immunity, population immunity, or social immunity)



In our present setting, the coronavirus only affects a very small percentage of the world population.  Even so, it is causing major disruption to the economy and to social functions.

A mathematical model for the unrestricted spread of infectious diseases, such as smallpox,  pertussis, measles, or coronavirus has been developed.  The model has been tested and proven by previous pandemics.  The variables in the equation are R (the number of infections transmitted by a single host) and S ( the proportion of the population who are susceptible to infection and setting this product to be equal to 1.

Viral entity                                R0                                   HIT       

Measles Airborne                    12–18                              92–95%

Pertussis Airborne droplet 12–17[51]                      92–94%

Diphtheria Saliva                       6–7                              83–86%

Rubella Airborne droplet          6                                       83–86%

Smallpox                                       5–7                                       80–86%

Polio Fecal-oral route

Mumps Airborne droplet           4–7                                 75–86%

COVID-19

(COVID-19 pandemic)              2–6                                50–83%

SARS

(2002–2004 SARS outbreak)               2–5                    50–80%

Ebola

(Ebola virus epidemic Bodily fluids      1.5–2.5               33–60%

Influenza

(influenza pandemics) Airborne      1.5–1.8                    33-40%

These are the facts, numbers do not lie.  

Prevention at the moment (summer 2020) may reduce the numbers, or flatten the curve but has the disadvantage of population variables, such as political motivation, willingness to comply with distance, wearing PPE, following CDC and WHO guidelines.  As we have experienced as soon as PPE, social distancing are removed the infectious rate quickly returns to a high level since the vast majority of the population is naive to coronavirus.


2  An effective vaccine.

Belgian virologist Guido Vanham, the former head of virology at the Institute for Tropical Medicine in Antwerp, Belgium, and asked him: how will this pandemic end? And on which factors might that depend?

Guido Vanham (GV): It will probably never end, in the sense that this virus is clearly here to stay unless we eradicate it. And the only way to eradicate such a virus would be with a very effective vaccine that is delivered to every human being. We have done that with smallpox, but that's the only example - and that has taken many years.

So it will most probably stay. It belongs to a family of viruses that we know - the coronaviruses - and one of the questions now is whether it will behave like those other viruses.

It may reappear seasonally - more in the winter, spring and autumn and less in the early summer. So we will see whether that will have an impact.

But at some point in this epidemic - and certainly in the countries that are most affected, like Italy and Spain - there will be saturation, because according to predictions, up to 40% percent of the Spanish and 26% of the Italian population are or have been infected already. And, of course, when you go over 50% or so, even without doing anything else, the virus just has fewer people to infect - and so the epidemic will come down naturally. And that's what happened in all the previous epidemics when we didn't have any [treatments]. The rate of infection and the number of those susceptible will determine when that happens.

This natural course, prior to vaccines places a demand on health services, significant morbidity, and mortality.  The cost of a natural process would exceed the cost of quickly developing an effective vaccine. Despite media exaggerating the mortality rate coronavirus kills few that it effects, mainly older and the chronically ill. Examining the R0 and HIT covid-19 is far less infectious than Pertussis and Measles.

Measles have been a chronic illness of children and when a vaccine developed it was eliminated very quickly.

The charts above display the rapid diminution of viral epidemics once vaccination begins. Normally the development of a safe and effective vaccine may take several years using previous technology.  Vaccines are now manufactured using RNA technology rather than growing batches of viral particles to be injected.  If the proper RNA is developed it can be injected directly into humans and the normal biochemistry of cells will develop the protein segment of the virus to be used as a vaccine. This means an entire viral particle is not necessary to produce immunity.

Several other factors could take place.  Covid-19 has exhibited some mutations in serotype already which are minor thus far.  A mutation could evolve spontaneously that would alter it immunologically and also it's pathophysiology.

Today pharmacology allows a pipeline to be developed to manufacture like products without having to reinvent the entire process.