Ebola’s early symptoms look a lot like the flu or malaria. What are US doctors doing to distinguish Ebola from other diseases?
With the first case of Ebola diagnosed Tuesday in the U.S., doctors are on alert for other cases of travelers from the region who might be infected and bring the virus back with them to the States. But what are they doing and, perhaps more pressing, what should they be doing?
Officials at the Centers for Disease Control and Prevention (CDC) have been expecting such a case, given how mobile the world’s population is. So the agency has published guidelines to help doctors and hospitals distinguishing Ebola, particularly in its early forms, from the common flu or other infections.
Complicating matters is the fact that Ebola can take as long as 21 days to incubate, after which the first symptoms, including fever, muscle aches, nausea, vomiting and diarrhea, might send sick patients to the hospital or their local urgent care center. But fevers, especially in October in much of the U.S., generally mean the flu—and most doctors won’t think twice about recommending a flu shot (if the patient hasn’t already been vaccinated) and some fever reducing medication before sending a patient home.
That needs to change, say infectious disease experts and CDC officials. “Given the current outbreak, I think all U.S. hospitals should review processes for evaluating patients with fever,” says Ryan Fagan, who is leading the domestic infection-control efforts related to Ebola for the CDC. “It’s good practice to take travel histories.”
“Asking the questions takes literally five seconds for most patients,” says Dr. Mark Kline, an infectious disease specialist and physician in chief at Texas Children’s Hospital. “It’s quick and it’s easy, and for 99% of patients we see, if they say they haven’t traveled outside of the U.S. in the last 21 days, that’s the end of the Ebola discussion right there.”
At Patient First, a primary-care and urgent care facility in Virginia, Maryland, and Pennsylvania, CEO Dr. Pete Sowers has been preparing an Ebola plan that will now be put into place. Patients will be greeted with a sign at the entrance and at the registration kiosk asking them to notify the receptionist if they have recently traveled to Guinea, Liberia or Sierra Leone and have any of the symptoms connected with Ebola. A nurse then meets the patient at the reception area and interviews them briefly to determine if they have potentially been in direct contact with the virus and if so, guides them to the nearest hospital. All staff are also educated about how to screen for common Ebola symptoms that might otherwise be mistaken for something else, like the common flu.
Similarly, at the University of Texas hospitals in Houston, nurses and staff who register patients in the emergency rooms or any of the clinics are trained to ask patients if they have traveled outside of the U.S. in the past 21 days. If they have, patients are asked where they have been. If the patient has been in Guinea, Liberia or Sierra Leone, they are brought to a separate room where they are given surgical masks and where health care personnel wear protective equipment, including gowns, gloves and masks, when entering the room.
Any hospital, no matter how small, has the capability of implementing such a system. Because Ebola is not an airborne virus, and can only be spread via direct contact with infected body fluids such as saliva, blood or other excretions, specially ventilated rooms aren’t necessary to contain infection and protect the rest of the hospital from getting exposed.
That’s why infectious disease experts are advising primary care doctors and those working at urgent-care clinics to adopt the same simple procedures: first asking patients about where they have been in the past month to triage those who are at highest risk of having Ebola, and also having a room ready for those who they suspect might be infected.
Even if they have recently traveled to the active Ebola areas in west Africa and have fevers doesn’t mean these patients harbor the virus. So far, says Fagan, hundreds of calls have come in to the CDC from local health departments about suspected cases of Ebola, and none, until the Dallas case, has been positive. Malaria and other infections also cause fevers that can last several days and make patients feel nauseous and weak. A quick look at a patient’s blood can reveal the malaria parasite under a microscope, and a relatively simple blood test can detect the genetic signature of the Ebola virus.
But it’s not practical nor necessarily helpful to run the Ebola test on every patient with a fever, says Fagan. Health departments and the CDC don’t have the resources to perform that many analyses, and even if they did, “if you test people who have low likelihood of having the disease to begin with, you start to run into problems with false positives since no test is perfect,” he says.
So here again, doctors have to rely on a much more labor-intensive but still effective technique: asking more detailed questions about their patients’ experience in the Ebola-stricken countries. Such as, did they have direct skin contact, or contact with the blood, urine, feces, saliva or vomit of an Ebola patient, or someone suspected of having Ebola? Did they have direct contact with the body of an Ebola patient during a funeral? Those patients would be at high risk of contracting Ebola, and would likely need a blood test to confirm presence of the virus. Doctors would take a blood sample and then call their local health department for testing, who would then notify the CDC, and both labs would likely perform analysis that looks for genetic signatures of the virus.
If the person had been in a home or health0care facility with Ebola patients, but didn’t have direct contact with them, they would be at medium risk of having the infection, and, says Fagan, public health officials would consult with the CDC to determine whether that person’s blood needed to be tested.
Despite the high death rate from Ebola in West Africa, health officials in the U.S. say that same toll is unlikely to be repeated here, since relatively easy infection control measures can be implemented in nearly every U.S. doctor’s office and clinic.