(ATLANTA) — After weeks of encouraging people to get tested if they may have been exposed to COVID-19, the Centers for Disease Control and Prevention abruptly changed course this week and is now telling the public testing might not be necessary.

The public health reasons for the change were not immediately clear.

When asked to explain, the Department of Health and Human Services — not the CDC — responded.

A spokesperson said in a statement that the new guidelines were updated to ensure testing is “used appropriately” and to “place an emphasis on testing individuals for post clinical and/or public health reasons,” including asymptomatic people.

“CDC recommends the decision to be tested should be one made in collaboration with public health officials or your health care provider based on individual circumstances and the status of community spread,” according to the HHS statement.

This new guidance directly contradicts what CDC Director Robert Redfield told ABC News last month: You don’t need symptoms to get tested.

Redfield’s comments came as case numbers in the U.S. were on the rise and health officials worried that younger people — attending protests and campaign rallies, as well as parties and bars — were driving the transmission.

Also in July, the CDC updated its guidelines online to specifically urge people without symptoms to get tested if they’ve come in contact with someone who has COVID-19, such as working the same shift at a job.

“Anyone who thinks they may be infected — independent of symptoms — should get a test,” Redfield told Dr. Jennifer Ashton, ABC’s chief medical correspondent, in July.

Since then, however, there have been reports of testing backlogs as much of the country tried to reopen and several universities tried to mandate testing for incoming students.

In new guidance dated Aug. 24, CDC says that so long as a person doesn’t show symptoms testing not necessary.

“You do not necessarily need a test unless you are a vulnerable individual or your health care provider or State or local public health officials recommend you take one,” the CDC states.

The quiet change comes amid questions on whether politics has leaked into public health guidance.

This week, the head of the U.S. Food and Drug Administration, Stephen Hahn, acknowledged that he overstated the benefits of convalescent plasma. With President Donald Trump at his side, he announced he was authorizing the treatment — frustrating some researchers who say they wanted to continue to conduct placebo-controlled clinical trials to see if it worked.

Trump later bragged that he got the FDA to act, despite the agency’s insistence that politics hadn’t influenced its decision.

On Wednesday, Hahn said he wanted to work on building trust with the public ahead of the vaccine trial.

“We at FDA recognize that we must build public trust so there is confidence in future decisions about vaccines for #COVID19,” he tweeted Wednesday. “I am concerned when I see public surveys that many people will decline taking a vaccine.”

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