Unvaccinated people infected with Covid-19 are likely to become "variant factories", infectious disease specialists said, as reported by CNN.

It turns out, an infected person's body is the only source of new coronavirus variants.

Mutations occur in unvaccinated bodies

"The more unvaccinated people there are, the more opportunities for the virus to multiply," CNN reported William Schaffner, a professor in the Division of Infectious Diseases at Vanderbilt University Medical Center, saying.

"When it does, it mutates, and it could throw off a variant mutation that is even more serious down the road."

Why vaccination is important

With unvaccinated people around, the virus can mutate in those bodies and even turn into something else that can bypass the vaccines currently administered.

Mutations mostly do nothing, but sometimes confer advantages to virus

Most mutations mean nothing to the virus, and some can weaken it.

But a virus sometimes develops a random mutation that gives it an advantage, such as better transmissibility, or an ability to infect a great diversity of hosts.

Viruses with an advantage will eventually make up the majority of virus particles infecting someone.

How unvaccinated people become a virus factory

An infected person will end up passing along the mutant version of the virus.

A variant occurs when a mutant version becomes successful enough as it spreads to others.

This occurs as an unvaccinated person allows that replication of a variant.

Every time the viruses change, they get a different platform for more mutations to spread more efficiently, Andrew Pekosz, a microbiologist and immunologist at the Johns Hopkins Bloomberg School of Public Health, told CNN.

In other words, viruses that don't spread cannot mutate.

This is the goal of vaccination.

Variants spread worldwide

Covid-19 coronavirus variants have arisen all over the world.

The B117 or Alpha variant was first seen in England.

The B1351 or Beta variant was first spotted in South Africa.

The B16172 or Delta variant was seen observed in India.

The U.S. has even come up with its own variants, including the B1427 or Epsilon lineage first seen in California, and the B1526 or Eta variant first seen in New York.

Covid-19 across time slightly different to virus mutations

One new variant has spread all over the world.

Around June 2020, a version of the virus carrying a mutation called D614G went from Europe to the U.S. and then the rest of the world.

The change made the virus more successful, so that version replicated better and took over from the original strain that emerged from China.

It appeared even before people named the variants, and it subsequently became the default version of the virus.

Most of the newer variants added changes to D614G.

The Alpha variant, or B117, became the dominant variant in the U.S. by late March thanks to its extra transmissibility.

Now the Delta variant is even more transmissible.

Threat posed by unvaccinated people

The current vaccines protect well against all the variants so far, but pockets of unvaccinated people will allow the virus to mutate.

If a virus tries to infect someone with immunity, it may fail, or it may succeed, and cause a mild or asymptomatic infection.

In that case, it will replicate in response to the pressure from a primed immune system.

This is why current vaccines work, but might fail if viruses mutate more rapidly.

Top photo via Xinhua