Think like a virus to understand why the pandemic hasn’t ended yet – and what the U.S. needs to do to help other countries


Karen Levy, University of Washington

Kill every person on the planet.

This is the first assignment I have given to students in my public health classes, which are full of workers passionate about saving the world. Their homework is play a game called Plague, where they pretend to be pathogens twisted to infect everyone in the world before man can make a cure or vaccine.

Why this assignment? Because as a professor of infectious disease epidemics, I want to teach students to think like pathogens so they know how to control them.

In COVID-19, thinking like a pathogen leads to the inevitable conclusion: Getting the vaccine all over the world as soon as possible is not a necessary behavior, but also a selfish one.

Transmission of genetic material is an important purpose

While many rich countries will soon offer vaccines to their entire population, people of poor countries may have to wait years for their shots. About half of U.S. residents are now at least partially vaccinated. Many other countries have not yet reached 1% vaccination coverage.

In the meantime, SARS-CoV-2 will take advantage of this opening.

In fact, pathogens never want to kill all of their human hosts, because eventually they are homeless. Their purpose is to pass on their genetic material to the next generation. They will do what they can to answer their evolutionary call.

A list of what to do with the virus

Of course, viruses and bacteria do not have a brain so they do not “think,” respectively. But like all life forms, these particular living creatures are tested increase their chances of reproduction and their children shall live and bear children.

As a virus fragment, there are two main things on the to -do list. First, you need a place to multiply. You need to make yourself a lot of numbers, to increase the chances that one of your kids will do the right thing and give you some grandchildren. As a virus you are very good at this little bit. No need to visit Tinder and find the perfect match, like multiplying your asexual. Instead you use your landlord’s cellular machinery – the person you are touching – to live for yourself.

Second, you need a way to get from your current host to the next host you can detect, if the transmission is unknown. For that you need both an exit portal – the way to get out of your current host – and an entry portal – the way to get in to your next host. You need an receptive host. And you need a way to travel to your next landlord.

Easy to host? That’s easy for SARS-CoV-2 on first arrival on the scene. Because it is a novel pathogen, the entire world’s population is easily caught. There are no people with full resistance to this particular virus from previous exposure, as there were no human populations before 2019. Now, for every person exposed or vaccinated, the number of portable hosts are reduced.

For a exit portal, SARS-CoV-2 has several options-mostly respiration through respiration, but also through feces and excretion of other body fluids. For an entry portal it has inhalation-it is inhaled by the new host-and to a lesser extent-it is inhaled by the new host orally.

This means that the transmission of this virus is quick, involving an activity that people of all ages do all day: breathing. Some viruses require more specific activities or conditions, such as having sex or sharing a needle for HIV, or biting a specific mosquito species for Zika.

A woman at a research site for asymptomatic COVID-19 in Portsmouth, England, on Feb. 22, 2021. Finnbarr Webster / Getty Images

SARS-CoV-2 is a smart virus

SARS-CoV-2 has many things played in its favor, except that there is a global population that has no appetite for it. There are many other traits that make it even more successful.

First, while it kills, it can also cause slow or asymptomatic infections to others. If pathogens kill most of their hosts, they are less successful in spreading, because people change their behavior in response to the perceived threat of disease.

Ebola a perfect example. College students are likely to cancel their spring break plans in Florida in 2020 if they expect it to cause them to bleed from their eyes, as has happened to some people infected with the Ebola virus.

SARS-CoV-2 also has a long incubation period-the time between its infection with a new host and the onset of symptoms in the host. However it can pass in time before symptoms occur, allowing it to spread unnoticed.

The women mourned hugging each other.
Family members of the COVID-19 victim mourned as they waited outside the funeral home of Maulana Azad Medical College to collect the body on May 24, 2021, in New Delhi, India. Sanjeev Verma / Hindustan Times via Getty Images

Lots of transmissions, lots of new races

If you think like the pathogen of SARS-CoV-2 today, you are annoyed to be looking for a way around today’s vaccine formulas. The more cases the cause, the more likely it is that there will be new varieties that can penetrate the vaccines. You don’t care if these cases happen in Montana or Mumbai. This is why no one is safe from a pandemic until shipping is controlled anywhere.

Thinking like a pathogen requires thinking beyond an evolutionary scale, which for a virus is very short, sometimes the course of a human infection. SARS-CoV-2 and other viruses have remarkable powers of adapting to changing conditions.

One of their survival strategies is the built-in faults in their reproductive machinery that cause change. Rarely, a change will occur that will improve a virus’s ability to survive and spread.

This will lead to the new different, such as those we saw coming up recently. To date, vaccines are available appear to be effective against races. Even newer varieties may reduce the effectiveness of the vaccine, or lead to the need for a booster shot. Increased transmissibility of new varieties is likely to arrive host of resistance by vaccination unreachable.

We watched in horror as the virus plagued India, and to some it may seem like a distant threat. But each new case offers an opportunity for a new variety to come out and spread around the world.

A woman receiving a vaccine in Ecuador.
Grace Macias, a farm worker working on the author’s projects, was vaccinated in Quito, Ecuador, on May 23, 2021. Grace Macias, CC BY-ND

To prevent the virus, we need shots everywhere

That is why access to the world of vaccines is not only a moral necessity but also a way to get rid of the virus. The U.S. can do a lot right now to ensure global access to vaccines even if we increase vaccination here.

The US has already done so many commitments on COVAX, a global collaboration to facilitate the development and production of COVID-19 vaccines and guarantee equitable distribution.

The US could bring in more funding now and force other countries to do the same. Funding COVAX’s commitments can be hollowed out that there is no simultaneous plan to immediately dispense the vaccine stockpile accumulated in the U.S. as we run to purchase the first available dose.

In addition to vaccination, the U.S. and other countries with more equipment could help increase there is a test in all countries. These countries can also provide technical and logistical assistance to improve vaccine launch efforts and work to coordinate and improve the world. genomic surveillance so new varieties are easily identified.

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If everything is so expensive, consider the devastating economic costs of going back to lockdown. This is not the time to be cheap.

To avoid jeopardizing the effectiveness of the millions of shots that go into the arms of rich countries, we need to get the shots of people in all countries.

Karen Levy, Associate Professor of Environmental & Occupational Health Science, University of Washington

This article was also published from The Speech under a Creative Commons license. Read original article.



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