Rabies is a rapidly fatal virus that affects the central nervous system causing encephalopathy and eventually death. It causes 40,000-60,000 deaths worldwide and 1-2 deaths annually in the United States.¹ The incubation period is typically 1-3 months but can be up to 7 years. Early symptoms are nonspecific but include malaise, fever, headache and pain which can be localized to the general area near the entry wound. As the disease progresses, neurological symptoms become more apparent like insomnia, anxiety, confusion, hallucinations, hypersalivation, difficulty swallowing and hydrophobia. Rabies is a public health concern because although preventable through timely pre- and postexposure interventions, once symptoms appear, death is usually imminent within a few days.

The virus is found in high concentration in the saliva of rabid animals. Transmission occurs when there is exposure through an animal bite, salivary contamination of breaks in the skin or mucous membranes, or by receiving donated tissues/organs with infected nervous tissue. Petting a rabid animal or contact with blood, feces or urine of an infected or suspect animal are NOT considered exposures. Bat bites may not be readily apparent and transmission can occur even when physical evidence of a bite is not found.

Pre-exposure vaccination and postexposure prophylaxis (PEP) are important in the prevention of rabies infection. Pre-exposure prophylaxis is given to people who are at high risk of animal exposure such as veterinarians, animal handlers, lab workers and international travelers to endemic areas. It is given as a series of 3 vaccines and may require serologic testing and a booster every 2 years.

Due to the potential of rabies transmission with a true animal exposure (such as a bite), the situation requires immediate action by the victim, medical provider and County agencies. An animal exposure should be reported by telephone (see Rabies Reports below) to the Anne Arundel County Department of Health and the Anne Arundel County Animal Control Unit. It is crucial that a timely medical evaluation be performed and a treatment plan implemented.

After a rabid animal exposure, all wounds should be cleaned and irrigated well, and a tetanus booster (either Tdap or Td) should be considered. Rabies immune globulin (HRIG) should be administered around the wound if possible. PEP for a non-vaccinated person includes 5 doses of the rabies vaccine (on days 0, 3, 7, 14 and 28). In a previously vaccinated person, only 2 doses of the rabies vaccine are required (on days 0 and 3), and rabies immune globulin should not be administered. In cases involving bats, PEP should be started when there has been a known or potential bite exposure, and the bat tests positive or is unavailable for testing. A rabies risk assessment algorithm has been developed by the Department of Health and Mental Hygiene and can be found at: http://www.edcp.org/vet_med/pdf/2005_Rabies_Algorithm.pdf

For dosages and other information, the CDC's Advisory Committee on Immunization Practices has released detailed guidelines for prevention of human rabies

Wild animals are the main reservoir for rabies accounting for greater than 85% of animal cases since 1976.¹ On the East Coast, including Anne Arundel County, raccoons are the primary reservoir for animal rabies, and bats account for the majority of cases in humans in the U.S. In the County, the number of terrestrial animal rabies cases has decreased substantially over the last decade. The graph below shows the trend in confirmed animal rabies from 1995-2007. In Anne Arundel County, about 70% of animal rabies cases are from raccoons. The Department of Health's successful Raccoon Oral Rabies Vaccination Project has helped to decrease the number of animal rabies cases in the County.

In 2007, 1,271 cases of human exposures to animals were reported in the County. The majority of 2007 cases of Anne Arundel County animal exposures were associated with dogs (47%), cats (22%) and bats (22%).

In 2007, the Anne Arundel County Department of Health recommended PEP for 117 exposed individuals, and 71 of those cases complied with recommendations and completed the full course of treatment. Out of the 117 cases where PEP was recommended 40% were dog exposures, 28% were bat exposures, and 21% were cat exposures. A high proportion of bat and raccoon exposures result in a recommendation for PEP because these two species are more likely to have rabies.

When the animal exposure is reported to Animal Control, every effort is made to identify and evaluate the animal. If necessary, a captured animal can be sent for rabies testing at the Maryland Department of Health and Mental Hygiene Rabies Laboratory. Quarantine for pets can be initiated and monitored through Animal Control.

The Department of Health maintains a supply of the rabies vaccine and rabies immune globulin for administration by medical providers. Arrangements for delivery can be made when the report has been received and reviewed by staff. If the provider's office is closed, urgent evaluation and initiation of the treatment plan can be done in local emergency departments. Department of Health staff are available for consultation 24 hours/day, 7 days/week to review animal exposure cases.

Anne Arundel County Department of Health Epidemiology and Immunizations Program
410-222-7256 (After office hours, a recording will provide a number for an operator.)

Anne Arundel County Animal Control 410-222-8900

Maryland DHMH Center for Veterinary Public Health