While enjoying a night boat ride on New Hampshire's Lake Winnipesaukee with friends, Adam Giroux suddenly felt something crawling up his leg. He jumped up, frantically trying to get whatever it was in his pants out of his pants.
"I finally got it out, and we saw that it was a bat," said Giroux, 27. "I wasn't sure if it had bitten me because there weren't really any bite marks. But to play it safe, I went to the emergency room."
Giroux explained his bat debacle to hospital staff. Moments later, doctors began administering rabies post-exposure prophylaxis.
"I got two shots in each arm and four shots directly into my stomach muscles, and then two months later, I was getting follow-up shots every other week," said Giroux. "It was pretty serious, but it was better than the alternative."
While cumbersome and certainly uncomfortable, the shots allowed Giroux to walk away from his bat encounter unscathed.
While most people think of dogs, raccoons or skunks as potential rabies carriers, bats are a major source of the disease in the United States, experts say. And on Thursday, the Centers for Disease Control and Prevention announced that a Mexican teenager had become the first person on U.S. soil to die from rabies after getting bit by a vampire bat.
According to the CDC's Morbidity and Mortality Weekly Report, the 19-year-old man arrived to work on a Louisiana sugar cane plantation in July 2010. After one of day working in the field, he began to experience fatigue, pain in his left shoulder and numbness in his left hand. His condition gradually worsened, and on Aug. 21, he died of rabies. After public health officials interviewed friends and family, they figured out that he had been bitten by a vampire bat in Mexico, 10 days before arriving in the U.S.
"This ... highlights the importance of a global perspective for human rabies prevention and the changing epizootiology of rabies," the Centers for Disease Control and Prevention wrote in the report. "Since 2000, eight of the 32 human rabies cases reported in the United States (including the case described in this report) were acquired from exposures abroad."
The rabies virus has an average incubation period of 85 days. In this case, symptoms showed within 15 days.
Once exposed, the rabies virus makes its way to broken nerve endings, then works its way back from the bite site toward the spinal cord.
"Once it's in the central nervous system, it attaches to the brain," said Dr. William Schaffner, chairman of preventive medicine at Vanderbilt University Medical Center. "Then there is inflammation of the central nervous system, and a person will get interference in the way they think and eventually lapse into a coma."
Experts say that as soon as exposure to a rabid animal is suspected, it's important to consult a doctor and receive a post-exposure prophylaxis vaccine. The vaccine will prevent them from getting rabies, which is almost always fatal.
"Because the rabies virus takes weeks to incubate, there is time for the vaccine to prevent disease even when given after exposure to the virus," said David Topham, associate professor of microbiology and immunology at University of Rochester Medical Center. "The man's death could have been easily prevented if he'd sought treatment in time."