With the Zika virus in the daily headlines, public health authorities should be looking carefully at how they communicate about this latest emerging infectious disease.

People need to be alerted, not alarmed.

That balance can be hard to strike when the health sources people turn to range from acquaintances on social media to politicians, instead of physicians and other medical professionals.

The Ebola outbreak in 2014 demonstrated that many of the old rules about public health communication no longer apply. Elected officials and media used to turn to professors or government public health officers. Now, headlines can be dominated and people can be swayed by a clever tweet or caustic comment on a talk show, even if they come from someone with no public health expertise.

Zika virus is considerably less dangerous than Ebola, but communicating about the risks requires some of the same delicate handling. In the past, politicians would yield and let physicians lead. In the Ebola outbreak, politicians not only demanded the spotlight, they often stoked fear by providing inaccurate information. Sen. Rand Paul, who has a medical degree, said that people could get Ebola just by helping someone into a taxi. There was no evidence to support that statement.

When scientists explained that Ebola isn't transmitted by casual contact, many members of the public didn't listen. A poll by Harvard researchers found that 4 in 5 Americans thought a person was likely to get Ebola if a person with Ebola coughed or sneezed on them or if they touched an object that had been in contact with an Ebola patient's body fluids. (Ebola transmission requires direct contact, such as when an Ebola patient's sweat gets into another person's body through a cut or the eyes, nose or mouth, according to the Centers for Disease Control and Prevention.)

Those of us who led medical center communications during the crisis had to play defense against false facts spread by people who should have been more responsible. Our experts had to get in front of people personally to overcome needless alarm stoked by misinformation in the media and elsewhere.

When Awareness Goes Awry

Errors in communications planning, preparation and practice contributed to unfounded hysteria about Ebola. As in the 2012 movie Contagion, fear can as dangerous as the infectious disease itself.

When World Health Organization Director-General Margaret Chan declared Zika virus a "public health emergency" on Feb. 1, her words were measured and precise. She focused on the need for international coordination to detect and study Zika infection cases and their consequences, develop tests and vaccines, and prevent new infections. She said there was no justification for travel restrictions. However, the CDC advised in January that pregnant women "consider postponing travel to any area where Zika virus transmission is ongoing."

A Reuters/Ipsos poll conducted in early February found that 41 percent of Americans who are aware of the Zika virus now are less likely to travel to Latin America and the Caribbean, where Zika virus cases have been reported. The poll also found that 60 percent of Americans are concerned about Zika virus, including 18 percent who are "very concerned."

Those poll numbers reflect that people worry, especially when they do not know much about the risks. With Ebola, people knew little more than that it was deadly. That lack of understanding undercut efforts by health officials to prepare for Ebola cases and manage the few that U.S. hospitals treated.

Getting accurate information out to more people in advance of an outbreak could have made a difference. That means more than just distributing messages via email. Texas Presbyterian Hospital executives apparently thought that distributing an Ebola policy to medical staff was sufficient preparation in case a person with Ebola might walk in the front door, as Thomas Earl Duncan did on Sept. 25, 2014.

"We believe that we were very well attuned to the potential risk of Ebola, and that we had communicated that fairly aggressively. What we didn't do is train and simulate for that," said Dr. Daniel Varga, chief clinical officer of Texas Health Resources, the company that operates Texas Presbyterian Hospital, in an interview with member station KERA.

Communication Requires Interaction

At Emory University in Atlanta, where Dr. Kent Brantly was successfully treated for Ebola, leadership figured out fast that face-to-face conversations were required to effectively inform hospital staff and media, says Vince Dollard, one of Emory's communications leaders.

When Dr. Craig Spencer was taken to Bellevue Hospital in New York with Ebola symptoms, there was plenty of hysteria, but health care workers throughout the city already knew the protocols, had gone through training and had fact sheets, posters and other materials on hand to help explain facts to concerned people. People may not believe government scientists, but they had a chance to get reliable information from their own doctors.

"One of the realities we learned and have to face is that today, many in the public simply will not believe a 'government expert' or top scientist anymore, not when they rely on Donald Trump, Sarah Palin and Jenny McCarthy for health information," says public relations consultant Kathleen Lewton, who has worked with hospitals for more than 30 years. "People stopped listening when it came to vaccines, so by the time we got to Ebola, experts from NIH and CDC were in some cases drowned out by others who saw a spotlight opportunity."

Lewton cites New Jersey Gov. Chris Christie as one example. On Oct. 22, 2014, Christie said elected officials "need to be responsible and cautious when talking about Ebola." Two days later, he and New York Gov. Andrew Cuomo announced mandatory quarantines for returning health care workers, despite objections from the National Institutes of Health and the CDC.

So far, with Zika, the tone has been relatively calm. The CDC was ready with posters, fact sheets and fliers. President Obama went on CBS This Morning on Feb. 8 with a clear, reassuring message: "The good news is this is not like Ebola, people don't die of Zika — a lot of people get it and don't even know that they have it," said the president. But he said Zika appears to present a risk to pregnant women and their offspring, echoing public health notices from both WHO and CDC.

Whether the public stays calm remains to be seen. Just as public health professionals keep watch for the next emerging disease, they also must anticipate the next source of fear and be ready to respond with more than just talking head experts. The days of waiting until an orderly news conference can be arranged are gone.

is former chief communications officer of Columbia University Medical Center in New York and has been an adviser to public health and other officials on crisis communications for more than 15 years. Previously he covered medicine and health atUSA Today.

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