The Centers for Disease Control and Prevention along with its director, Dr. Rochelle Walensky, have come under critical fire for their mixed messaging during the COVID-19 pandemic.

According to NBC News, the lack of consistency in the CDC’s policies has added to the uncertainty and confusion of the pandemic. While millions of Americans have been vaccinated and many states are relaxing their restrictions, the number of COVID-19 cases continues to rise.

“One of the most important things we say in public health is that you have to have a very simple message,” said Dr. Wafaa El-Sadr, M.D., a professor of epidemiology and medicine at Columbia University. “But we’re in a situation where the message is very complex.”

For example, according to NBC, Walensky told MSNBC on March 29 that “vaccinated people do not carry the virus.” When scientists questioned her statement, the CDC walked back her remarks. When the agency relaxed its travel guidelines for people who are fully vaccinated despite the rising number of COVID-19 cases, Walensky contradicted the agency and said, “I would advocate against general travel overall.”

This back-and-forth communication has eroded public trust, say healthcare experts.

According to NPR, the public’s confidence in the CDC dipped to an all-time low during the pandemic. One of the reasons was the agency’s mixed messaging.

“Whether you’re a public health agency or doing a communications campaign of any kind, an erosion of trust is incredibly damaging,” Alison Buttenheim, a public health researcher and behavioral epidemiologist at the University of Pennsylvania, told NBC.

Dr. Vinay Prasad, a leading health researcher and associate professor at the University of California, San Francisco, was blunt.

“CDC messaging on restrictions post vax has been a mess,” he tweeted.

According to NBC, the CDC missteps mirror the changing landscape of the pandemic and health messaging is a challenge when the terrain is constantly shifting. Dr. Sandra Albrecht, a formally trained social epidemiologist and associate professor at Columbia University who previously worked for the CDC, said that while people want black and white answers to their risk potential during the pandemic, the nuances of COVID-10 make this an impossible task.

“Risk is a spectrum,” she said. “It depends on the context, the circumstance, the individual, geography. There are so many factors that contribute to risk that it’s really hard to deliver one line of public messaging for everyone.”

Albrecht and Buttenheim foresaw the potential for messaging mishaps early in the pandemic, and according to NBC, created Dear Pandemic, an online project to help the public navigate the deluge of information.

“A lot of what we’ve done is discuss the reasons and the motives behind public health massaging that comes from the CDC, because the public is confused,” said Albrecht. She said that as a scientist, she is able to unravel and explain why the CDC and other public health agencies often change or even reverse their recommendations. One of the big issues early in the pandemic was the CDC and the World Health Organization’s vacillation on the wearing of masks.

Albrecht said that the reasons for the change in guidance were not properly given to the public.

“That caused a lot of confusion and gave fodder to conspiracy theorists,” she said, per NBC. Experts called for the CDC to be more transparent in its information, sharing the scientific evidence and being cautious when they are not sure what the next steps should be in containing the pandemic. This honesty and transparency is especially important as new cases are rising and variants are spreading.

How Americans respond to the virus in the next crucial weeks could change the trajectory of the pandemic in the U.S., said Loren Lipworth, an epidemiologist at Vanderbilt University Medical Center.