CDC outlines Ebola risk levels, potential public health actions
The CDC has released new guidelines that outline four different levels of exposure to Ebola among travelers returning from West Africa and the potential public health actions that health departments can take.
The four levels of exposure are: high-risk, some-risk, low but nonzero risk and no identified risk. Examples of high-risk individuals include those who have received a needlestick or who have had known exposure to a patient with Ebola with no protective equipment. Examples of some-risk individuals include people who have been in households of patients with Ebola but had no direct contact and health care workers returning from West Africa where they have been working with patients.
“About 100 individuals per day, on average, are returning from the three affected countries of West Africa and about 5 or 6% have a background working in health care,” CDC Director Thomas Frieden, MD, MPH, said during a media briefing. “These guidelines increase the level of protection for Americans and at the same time recognize the heroic work these individuals are doing in Africa.”
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Thomas Frieden
Low but nonzero risk includes people who traveled through the affected countries but had no known exposure, and people with no identified risk are those who did not travel to the affected countries or traveled more than 21 days ago.
In terms of public health actions, Frieden said the first is active monitoring, in which local health authorities take responsibility for the daily monitoring of the patient and his/her symptoms. If they develop symptoms or an elevated temperature, they are rapidly evaluated and if appropriate, isolated and treated. People in the high-risk group may undergo direct active monitoring, when a member of the health authorities takes the person’s temperature in person and reviews plans for activities.
“Active monitoring is so important because it can identify patients in the early course of illness,” Frieden said. “We know with Ebola, as people get sicker, they get much more infectious. The first few hours of symptoms are far less likely to result in any infections than later courses of disease when people have much larger numbers of virus.”
Frieden said that individual states have the authority to enact stricter precautions based on individual assessments, such as a do not board order, restriction on use of public transport or restrictions on congregate activities.