Those Infected With COVID-19 Could Be Immune for Just 3 Months, CDC Says

Individuals who contracted COVID-19 but remained symptom-free after the initial quarantine period has passed are immune for up to three months, according to information from the Centers for Disease Control and Prevention (CDC).

How long a person remains immune to the coronavirus after an infection has been the subject of research since the pandemic began in March. Some individuals have contracted the virus without showing any outward symptoms of being ill. Testing for the virus has proven to be unreliable at times with some specimens returning a false positive result. Others have posited the theory that if enough people get sick, the entire population will gain immunity.

In guidance that was updated in August, the CDC gave a concrete time period for how long immunity against the coronavirus is expected to last. "People who have tested positive for COVID-19 do not need to quarantine or get tested again for up to 3 months as long as they do not develop symptoms again," read the CDC website. "People who develop symptoms again within 3 months of their first bout of COVID-19 may need to be tested again if there is no other cause identified for their symptoms."

Quarantine is still recommended to last for 14 days from the date an individual first came into contact with a person who may have been exposed to COVID-19. If a member of the household becomes ill with the virus, or the person under quarantine should come into contact with another infected individual, quarantine should be restarted from the date of the latest contact.

In a statement sent to Newsweek on Friday, the CDC clarified its guidance update. "Contrary to media reporting today, this science does not imply a person is immune to reinfection with SARS-CoV-2, the virus that causes COVID-19, in the 3 months following infection," the CDC said. "The latest data simply suggests that retesting someone in the 3 months following initial infection is not necessary unless that person is exhibiting the symptoms of COVID-19 and the symptoms cannot be associated with another illness."

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People who have recovered from bouts with COVID-19 may be immune for three months according to guidance from the CDC. iStock/Getty

Some observers have expressed hopes that the U.S. will achieve herd immunity to the coronavirus. Herd immunity occurs after a majority of people contract a disease and recover from it, thereby raising the number of immune individuals. Without enough people able to function as disease carriers, the virus would eventually die out.

During a Friday Instagram stream, infectious diseases expert Dr. Anthony Fauci said if the U.S. were to attempt to achieve herd immunity, many people would not survive.

"If everyone contracted it, even with the relatively high percentage of people without symptoms," Fauci said, "a lot of people are going to die."

Fauci cited the number of Americans with underlying health issues as potentially contributing to the high fatality rate. "You look at the United States of America, with our epidemic of obesity, as it were," Fauci said. "With the number of people with hypertension, with the number of people with diabetes, if everyone got infected, the death toll would be enormous and totally unacceptable."

President Donald Trump said in May that if the U.S. had attempted to attain herd immunity, the death toll would have been "unsustainable."

"So many people have died," Trump explained during a meeting with Republican lawmakers at the White House. "That's the one thing we can't do anything about, unfortunately. What I can say is if we did it the different way—if we went 'herd,' if we just said 'let's wing it'—we would've been talking about numbers that would've been unsustainable and unacceptable."

Information from the CDC says 70 percent of the U.S. population, which represents more than 200 million people, would have to contract COVID-19 and recover for natural herd immunity to occur. "If many people become sick with COVID-19 at once," the CDC website says, "the health care system could quickly become overwhelmed."

Recent data indicates 5,462,243 positive cases of COVID-19 in the U.S. with 171,210 fatalities attributable to the virus.

Updated 12:12 a.m. EST 08/15/2020: This story has been updated with a statement from the CDC.