Unvaccinated people face more than double the risk of COVID reinfection, CDC says

A new study of hundreds of Kentucky residents reveals more real-world data that shows COVID-19 vaccines offer better protection against reinfection than natural immunity.

Among nearly 740 people who previously had tested positive for the coronavirus, those who remained unvaccinated were more than twice as likely to contract COVID-19 again than people who were fully vaccinated.

The findings, published Friday by the Centers for Disease Control and Prevention, suggest vaccination serves as an extra layer of protection against reinfection even if you’ve already had COVID-19, especially as more contagious coronavirus variants continue to hospitalize and kill hundreds every day.

“If you have had COVID-19 before, please still get vaccinated,” CDC Director Dr. Rochelle Walensky said in a statement. “Getting the vaccine is the best way to protect yourself and others around you, especially as the more contagious delta variant spreads around the country.”

The new study adds to existing evidence that shows vaccinated people who get infected are more likely to have milder and shorter illnesses compared to the unvaccinated. Experts say this suggests they are less likely to spread the virus to others; less coughing or sneezing means fewer opportunities for the virus to latch onto others.

The delta variant, however, has challenged this idea.

Delta loads people with more virus particles

The most recent data shows the delta variant is more transmissible than the common cold, smallpox, Ebola, influenza and the 1918 “Spanish” flu, according to the CDC, and that it is as transmissible as chicken pox.

Part of the reason is that the variant arms people with more virus particles in their noses and throats, causing more severe disease that increases risks of hospitalization and death.

A study from China found that the viral load in delta-infected people was about 1,000 times higher than in people infected with the original version of the coronavirus.

And despite vaccination status, age or other health conditions, the delta variant still presented a 120% higher risk of hospitalization, 287% higher risk of intensive care unit admission and 137% higher risk of death, according to a study from Canada.

Regardless of how immunity is acquired, there’s no telling whose bodies will or won’t create effective antibodies against the virus, and why they last longer for some than others; doctors speculate age or certain medical conditions might play a role.

‘Vaccines save your life’

However, to date, evidence shows the vaccines are doing “exactly what they were supposed to do: prevent severe disease, hospitalization and death,” Walensky said during a White House COVID-19 briefing on Monday.

As of Aug. 2, when more than 164 million people in the U.S. had been fully vaccinated, the CDC reported 7,525 breakthrough infections among the vaccinated who were sick enough to be hospitalized or die. A total of 1,507 of them have died. That’s less than 0.001% of those who had been fully vaccinated at the time.

“People should be reassured that if they are fully vaccinated that they are very likely, highly likely, to be protected against severe or critical illness, the kind of illness that would cause them to be hospitalized or killed by this virus,” Dr. Paul Offit, a vaccine expert at Children’s Hospital of Philadelphia, told The Washington Post. “Vaccines save your life.”

More than 165.6 million Americans are fully vaccinated against COVID-19 as of Aug. 5, or about 50% of the U.S. population, according to a CDC tracker.