Can we actually learn to live with the coronavirus?Until vaccination

Entering the final quarter of 2020, the virus that defined this problematic year is showing no signs of disappearing. Some say that in the absence of vaccines and broadly effective treatments, one needs to learn to live with COVID-19. But what does it really look like?

In summary, this is a complicated question. Is it necessary to disseminate SARS-CoV-2 to the majority of the population, protect all older people and those at high risk of serious illness, and give the population some basic immunity? Or is it better to keep up with the countermeasures and aim to get rid of the virus?

When trying to answer a question, the concept of “herd immunity” (when about 60% of the population is immune to the disease) is often called up. However, the term is not well understood. Control of infectious diseases by the accumulation of innate immunity in the population has never been achieved. Herd immunity works with targeted vaccination, but there is no COVID-19 vaccine yet.

Virus and immunity

Let’s look at an example of smallpox. It is a highly infectious and horrific disease and is the only human virus ever eradicated. Unlike COVID-19, people infected with the virus were always symptomatic and could be found and quarantined. Anyone who does not die will be protected for life.

But we only completely remove it from the world through a collaborative vaccination campaign. This was the only way in the world to achieve a sufficiently high level of protection to reach the herd immunity threshold.

About a quarter of all common colds are caused by the type of coronavirus. Since SARS-CoV-2 is also a coronavirus, is it possible that a similar protective crossover will occur? We do not know how long the protection against the coronavirus will last after recovery, but we do know that it will not last forever.

For example, one recent study shows that some people get sick multiple times with the same type of coronavirus in the same winter season. This indicates that innate immunity cannot be assumed as a fact of the relationship between humans and coronaviruses, and that herd immunity probably does not occur naturally. Indeed, it is worth noting that if we can achieve innate immunity without vaccines, we have never seen it before.

Spread control

Why not try to get rid of SARS-CoV-2 by controlling its spread? This happened with relatives SARS-CoV (Sars) and MERS-CoV (Middle East Respiratory Syndrome), both of which are associated with the bat coronavirus. These diseases emerged in the 21st century and presented new pathogens to which the human immune system responds, which could be a useful example for predicting what would happen with COVID-19.

Sir’s went around the world twice between November 2002 and May 2004 and then disappeared altogether. This is due to strict controls, such as quarantine contact with infected individuals and regular and thorough cleaning of public areas.

A robust laboratory test scheme has been set up. People were advised to wear face masks and wash their hands frequently. These measures stopped the spread of the virus among people and extinct the virus.

The advantage of trying to contain Sars was that most infected people developed symptoms so quickly that they could be identified with the necessary medical assistance and isolated from others. Unfortunately, COVID-19 appears to be the most infectious at the beginning of the disease, but people are mild or asymptomatic and cannot do the same effectively.

Mers first received attention in the Middle East in 2012. It causes a very serious illness and kills 34% of those who catch it. It seems to be less infectious than SARS and SARS-CoV-2. To spread the disease, people need to be in close contact.

As a result, Mers patients tend to give it to those who care for them and their close relatives in the hospital. This made it easier to contain the outbreak and prevented the disease from spreading too geographically. There are still major outbreaks, including 199 in Saudi Arabia in 2019.

Like Mers, unlike Sars, COVID-19 outbreaks are expected to occur even after more or less control. The important thing is to identify who is infected as soon as possible through testing and contact tracing to reduce the number of people affected by a particular incident. Effective and widely used vaccines help to reach this stage early.

calm down

Comparison with influenza outbreaks also helps to understand what the “coexistence” of COVID-19 looks like. The Spanish flu of 1918-20 infected 500 million people and is estimated to have killed about 50 million people. Between January 2009 and August 2010, at least 10% of the world’s population was probably infected with swine flu in Mexico, but the death toll was just over 250,000, with the expected rate of seasonal flu. It was almost the same.

A 1918 newspaper article introducing a new type of mask to protect healthcare workers from the Spanish flu.The Washington Times

The 1918 and 2009 viruses are the same type of influenza A called H1N1. So why was the swine flu mortality rate so low? In the 21st century, clinical testing for influenza was a daily routine, with effective antiviral treatments (Tamiflu and Relenza) and vaccines. The virus also mutated, reducing the risk.It calms down and joins all other seasonal influenza strains, now known as H1N1pdm09

Does the same thing happen with COVID-19? Unfortunately not. Although there are accurate laboratory tests for SARS-CoV-2, they were invented only in 2020. The test required the hospital’s microbiological laboratory to continue all normal work, but it did add extra work.

Antiviral remdesivir is only used to treat people who are already hospitalized with severe COVID-19. It is unlikely that the vaccine will be ready by the spring of 2021. There are several new strains of SA RS-CoV-2, but unfortunately they are about the same as or more infectious than the original strain. The virus has yet to show signs of calming down.

Escape route

Most people infected with COVID-19 recover, but about 3% of people worldwide who test positive have died. It is not known what percentage of people who have achieved some kind of recovery develop long-term side effects (known as long-term COVID), but it can be up to 10%. Studies of people infected with SARS in the early 2000s show that some of them still have lung problems 15 years later.

In the face of these statistics, we should strive to protect as many people as possible from COVID-19 infection, rather than “learning to live with the virus.” Daily measures should be continued to prevent the coronavirus from passing between people as much as possible. During 2020, it meant varying degrees of blockade imposed by the government in most countries.

In the medium term, we need to balance limiting people’s freedom with being able to meet loved ones and earn a living. However, SARS-CoV-2 is different from smallpox, unlike SARS and Mars, and different from Spanish and swine flu. There are lessons that can be learned from these previous infections, but this goes beyond the lesser-understood concept of learning to live with herd immunity, elimination, or the virus.

The outbreak of SARS-CoV-2 seems to be a reality for some time, but “learning to live with the virus” means infecting many people. It’s not a thing. The plan is to make sure that very few people are infected so that new outbreaks are small and rare.conversation

Sara Pitt, Chief Lecturer of Microbiology and Biomedical Sciences Practice, Fellow of the Institute of Biomedical Sciences, University of Brighton

This article has been republished by The Conversation under a Creative Commons license. Please read the original article.

Can we actually learn to live with the coronavirus?Until vaccination

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