Baltimore Area Residents Warned To Avoid Vaccine Bait

Residents in the counties surrounding Baltimore Maryland are being advised to closely watch pets and avoid bait blocks placed to vaccinate raccoons for rabies. According to a case report by the CDC, contact with the bait is confirmed to cause skin irritation and Human Vaccinia infection. (Summary can be found below)

The most recent case of rabies with raccoons was reported by the Baltimore City Health Department, a raccoon removed in the area of Schenley Road in the Roland Park neighborhood in response to a wildlife control call resulted in a positive rabies result after being tested. (1)

Rabies Vaccine Bait For Raccoons

Maryland — The annual raccoon oral rabies vaccination project carried out by the Anne Arundel County Department of Health began Thursday. Residents are advised to avoid baits that will be placed across the county. The project should wrap up soon, weather permitting.

The baits contain the liquid rabies vaccine and will be placed in neighborhoods by trained health department employees wearing shirts featuring health department logos. Baits also will be dropped from a low-flying county police helicopter in less populated areas.

The bait will either look like a ketchup packet with a light brown waxy coating or a small brown brick with a plastic packet inside. Anyone who comes in contact with the bait or has a pet that encounters the bait should call 410-222-1423 weekdays and 443-481-3140 evenings and weekends.

The vaccine is designed to vaccinate raccoons when the animal bites into the vaccine packet. It cannot cause rabies and is not harmful to raccoons, pets or other animals. While it does have a very low human health risk, the health department advises that youth, pregnant women and anyone with a chronic skin condition contact their doctor if they handle it.

The health department also recommends that pet owners keep their pets confined or on a leash during the baiting period and for two weeks thereafter. If your pet finds a bait, carefully remove the bait from your pet's mouth. (2)

CDC Case Report

A woman aged 35 years was picking blackberries in a rural area of Pennsylvania where ORV baits recently had been distributed. Her dog picked up a bait in his mouth and punctured the bait with his teeth. After the dog dropped the bait, the woman picked it up, and V-RG vaccine dripped from the bait onto her right hand and wrist, including sites that had been abraded by blackberry thorns.

Approximately 30 minutes passed before the woman was able to wash her hands. She telephoned the ORV helpline number printed on the bait, and her call was referred to PADOH. The woman had a history of inflammatory bowel disease, for which she was taking multiple immunosuppressive medications. These medications included a suppressor of T and B cell proliferation (taken daily) and a tumor necrosis factor-alpha (TNF-alpha) blocker (taken once every 6 weeks, with the last dose on July 13); she had no smallpox vaccination scar and reported no history of smallpox vaccination.

On day 1 after her exposure to the V-RG vaccine, her physician obtained a baseline serum specimen for analysis of rabies virus neutralizing antibody (by direct virus neutralization) and orthopoxirus (vaccinia) immunoglobulin IgG and immunoglobulin IgM antibodies (by enzyme-linked immunosorbent assay).

In addition, photos were taken of her right hand abrasions, and she was instructed to watch for signs of infection in her hand.

On day 4, she reported several red papules on her right hand. She visited a local hospital emergency department, where scrapings of the papules were obtained and submitted to the PADOH Bureau of Laboratories. The woman was discharged from the emergency department and advised to stop taking her immunosuppressant medications.

On day 5, a real-time polymerase chain reaction (PCR) assay of the scrapings tested positive for nonvariola Orthopoxvirus DNA. Subsequent testing performed at CDC confirmed the presence of vaccinia virus DNA and rabies virus G protein DNA in papule material and serologic evidence of rabies virus neutralizing antibodies. Neither Orthopoxvirus IgG nor IgM antibodies were detected.

On day 6, the papules had increased in number and size, and the patient was hospitalized. Physical examination on admission showed multiple papules on erythematous bases on the patient's right hand, wrist, and arm, including three that appeared to be early vesicles. Because of the patient's immune suppression and concerns about progressive vaccinia, she was administered a single dose (6,000 IU/kg) of VIGIV (Cangene Corporation, Winnipeg, Canada) provided by CDC. Contact precautions were utilized while the patient was hospitalized.

On day 9, she had 26 classic vaccinia virus lesions, including one on a site on her right arm that might not have been in contact with the vaccine initially. The patient was afebrile and not experiencing symptoms related to her inflammatory bowel disease. However, on day 11, she experienced myalgia and headache; she had pronounced redness and edema in her right hand (Figure 2), accompanied by right axillary adenopathy. (3)

Bottom Line

If you come into contact with anything foreign, or remotely resembling these baits put out for raccoons, please be careful and avoid them all all costs. If you have questions concerning getting rid of raccoons that may potentially be sick or living in your home, call us at (410) 982-5050 to reach one of the specialists at On The Fly Pest Solutions for professional consultation and your potential options for remediation of the situation.