By Saumya Joseph

(Reuters Health) – Human rabies deaths are so rare in the United States that even healthcare providers may not recognize a rabies infection – or the role that bats might play – which puts patients and the public at further risk, researchers say.

In a report from Utah, doctors describe the state’s first rabies death since 1944, stemming from exposure to bats in the man’s attic.

By the time he was correctly diagnosed, it was too late. Weeks had passed in which the man saw multiple healthcare providers and was transferred between hospitals, exposing potentially hundreds of health workers and others.

Dallin Peterson of the Utah Department of Health in Salt Lake City and her colleagues detail the case and the public health response as a cautionary tale in the Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report.

“It’s an odd, unique incident,” said Peterson, stressing that when a patient comes in with unexplained neurologic symptoms, physicians should ask about exposure to wild animals and consider rabies as a possible diagnosis.

Domestic dogs are no longer considered a source of rabies in the U.S., but exposure to wild animals such as bats, raccoons and skunks result in the need to observe or test hundreds of animals and to administer post-exposure preventive treatment to 30,000 to 60,000 Americans, according to CDC figures.

Bats are the primary reservoir for rabies in Utah, the authors write. Over the past decade, an average of 95 bats a year have been submitted to the state lab for testing, with 15%-20% turning out positive for rabies.

In the case of the 55-year-old Utah man, he first sought chiropractic treatment on October 17, 2018, for neck and arm pain he blamed on a recent work-related injury. Two days later, he was evaluated in an emergency room but showed no sign of fever or infection. The next day, he developed shortness of breath and lightheadedness, with severe esophagus spasms leaving him unable to swallow fluids, and he was admitted to a second hospital.

With worsening symptoms, high fever and delirium, the patient was transferred to a third hospital on October 21. By October 25, he was comatose and a day later started having uncontrolled seizures that prompted transfer to a fourth hospital. On November 3, an infectious disease expert at that hospital was consulted and suggested the possibility of rabies. The man died on November 4.

When questioned about exposure to wild animals, the patient’s family reported the man had extensive contact with bats infesting their home in the months before the illness began.

Unlike dog bites, which are relatively memorable events, most people fail to even realize they have been in the presence of bats, said Guy Palmer, a professor of infectious diseases at Washington State University, in Pullman, who wasn’t involved in the study. “Then the problem is, they don’t go for postexposure prophylaxis and once you begin to develop symptoms of rabies, death is inevitable.”

Most people tend to drive bats out of their houses rather than capture the animals and send them for testing, he added. “That’s where the challenge comes in and why a case like this has such a burden on the healthcare system – because of uncertainty of exposure, but certainty of the consequence of an infection,” Palmer said in a phone interview.

Of 37 close family and community contacts, 30 were considered potentially exposed and given postexposure prophylaxis. Because the man had so many contacts at multiple healthcare facilities, a total of 242 health workers were also canvassed and 74 of them given prophylactic treatment.

“I don’t think anything went wrong, at least on the public health side,” Peterson noted, “just the lack of education on the general public side made it hard for the medical providers to know what was actually going on with the patient.”

SOURCE: Morbidity and Mortality Weekly Report, online February 7, 2020.