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HealthCoronavirus

Do COVID vaccines stop coronavirus from spreading or just make you less sick?

By
Sy Mukherjee
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By
Sy Mukherjee
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February 2, 2021, 9:55 AM ET

COVID vaccines have their work cut out for them. The various candidates from Pfizer/BioNTech, Moderna, Johnson & Johnson, and AstraZeneca have been the main players (particularly Pfizer and Moderna as the only two companies with an FDA emergency-authorized shot). But there’s a crucial mystery still left to unravel: Do these vaccines simply stop you from getting really sick, or can they actually stop transmission of the coronavirus itself?

Unfortunately there isn’t anything approaching a clear-cut answer to that yet. The rapid production timeline for these immunizations means we need to wait and see all the data. But vaccination is still crucial in the fight against the pandemic despite the unknowns, according to public health experts, and fairly typical when it comes to immunization campaigns.

In order to understand why, it’s important to know how a virus spreads and what vaccines really do.

You see, unlike bacteria, which can exist without infiltrating a host cell, viruses need to hack into your biological machinery in order to do their bidding. The coronavirus latches on to cells via a mechanism called a “spike protein,” and that’s how it replicates itself. It literally turns your body into a disease manufacturing plant.

This is what makes viruses so tricky. They’re significantly smaller than bacteria and, by way of their relative simplicity, can be difficult to contain.

A vaccine’s main purpose is to create an immune response. You’re essentially training up your cells so the immune system is ready once the villainous pathogen smashes through the door.

That doesn’t mean that you won’t get infected, or maybe even get sick from COVID if you do contract the coronavirus. But studies have shown that currently available COVID vaccines can, at the very least, weaken the virus enough to stave off serious and deadly illness.

Achieving “sterilizing immunity,” which prevents a pathogen from causing new infections in other people (including COVID cases in which someone may be asymptomatic or just mildly sick) is the ultimate goal. After all, one person’s asymptomatic or mild COVID sickness could easily turn into a high-risk individual’s death sentence if the person contracts the virus.

But with more data needed on how effective these vaccines are at preventing coronavirus transmission, the message from public health officials is clear: Get the vaccine once you qualify in order to weaken the virus and lower the chances of spreading it to others.

As frustrating as the uncertainty is, it’s nothing new in the world of vaccines. For instance, the vaccine that guards against the whooping cough is highly effective at making sure you don’t get extremely sick but not so much when it comes to spreading the underlying pathogen. But other vaccines such as the one for stomach-churning rotavirus help prevent transmission while not necessarily making someone who catches the bug less sick.

Despite the X factors, the overwhelming medical consensus is that it’s better to get a vaccine when you can, since at the very least it will protect you and may protect many others.

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By Sy Mukherjee
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