Tri-colored batThe latest edition of CDC’s Morbidity and Mortality Weekly Reports describes a case of rabies in a Missouri man. Rabies is rare in people in the US, but it remains an ever-present risk because the virus circulates in various wildlife species. (This case seems to have been from 2014, but they missed some proofreading since both 2014 and 2015 are stated).

The case involved a 52-year-old man who first went to the local hospital emergency department because of neck pain. He was given some pain medication and muscle relaxants, and sent home.

  • The next day, he had some numbness, tingling and other progressive signs, so he went back to emergency, where he was diagnosed with a herniated disc and sent home with more drugs.
  • That night, his symptoms got worse. He became anxious and fearful, and started hallucinating, and was taken back to the hospital. There, he was diagnosed with a reaction to the drugs he was on.
  • The next day, he couldn’t swallow his medications, and he developed more signs of neurological disease. He ended up on a ventilator shortly thereafter because of respiratory failure.

A wide range of tests was then done and a wide range of treatments was provided. As his disease progressed and nothing worked, rabies was considered. Family members reported that he lived in a trailer in a wooded area, but they didn’t know about animal exposures. Rabies was eventually confirmed, and he died a couple of days later. The “Milwaukee protocol’, a rabies treatment plan that has resulted in a handful of rabies survivors, was not used because his condition was so bad by the time rabies was diagnosed.

As always, an investigation occurred, with two main emphases. One was to find out if anyone exposed to the infected patient needed post-exposure treatment. The other was to figure out why/where/how/when he was infected.

  • Nine family members and friends, and seven healthcare personnel were identified as having high-risk exposure and received post-exposure prophylaxis for rabies.
  • The rabies virus strain that was isolated was a bat rabies strain found predominantly in the tricolored bat (Perimyotis subflavus). The man had apparently reported seeing a bat in his home a few weeks before he got sick. When the trailer was inspected, bats were not found but there were several places where a bat could get it. There was also the potential for exposure at work, since we worked in a warehouse where bats were occasionally seen.

It’s easy to look back and wonder why they didn’t consider rabies earlier. However, rabies is a “great pretender” and can be confused with a wide range of more common disorders. Also, questions about animal exposure are too often not asked until quite late in the process, rather than being a standard part of history taking. While it’s a longshot, earlier questions to identify potential rabies reservoir exposure and earlier consideration of rabies could possibly allow for earlier treatment and a potential (albeit slim) for survival.  More importantly, education regarding the risk of exposure to bats and other reservoir species is critical – if the patient knew he’d had direct contact with a bat (which isn’t always the case) and reported it right away he could have received post-exposure prophylaxis to prevent infection, which is vastly more effective than attempting treatment once signs appear.

Image: Tricoulored bat (Perimyotis subflavus)(credit: Larisa Bishop-Boros)