Discussion
This report describes the public health response to two cases of B. procyonis eosinophilic meningoencephalitis in unrelated pediatric patients reported during a short period (September 2024) in Los Angeles County, California. Few cases of B. procyonis eosinophilic meningoencephalitis have been documented in the United States (5,9), and most of these patients have been young, male children with developmental disabilities, often with pica; however, infections have occurred in older age groups and in persons with occupational exposure (5). Despite its severe adverse health effects, the true incidence of B. procyonis infection in humans is not well understood. A recent serologic study in Santa Barbara County, California found a 7% seroprevalence in the general population (10), suggesting that asymptomatic or subclinical human infections are more common than previously thought; thus, asymptomatic cases might not be diagnosed.
Outcomes of B. procyonis infection can be severe if diagnosis and treatment are delayed, as was the case for patient B. The patient did not receive a diagnosis for approximately 3 months, resulting in severe neurologic sequelae. A clinician who had encountered a case before treating patient A suspected baylisascariasis in both patients A and B, suggesting that heightened awareness by the health care provider might have contributed to their diagnoses. This clinician’s observation highlights the possibility that similar cases might not be diagnosed without improved awareness among health care providers of the possibility of B. procyonis infection.
Epidemiologic investigations suggested the possible exposure of patient A at his residence where a raccoon latrine was present and where he was suspected to have consumed material contaminated with raccoon feces. Additional environmental investigations would be necessary to confirm that the feces at the residence were the source of infection. Identifying a potential source of infection for patient B was not successful; however, his family reported that he regularly placed soil and other objects in his mouth in outdoor areas that might have been frequented by raccoons.
Implications for Public Health Practice
Given the severity of disease in humans, the high prevalence of B. procyonis infection in raccoons, and the proximity of raccoons to humans and pets, B. procyonis is a substantial public health concern. To prevent infection, the public should avoid contact with raccoons and their feces, not keep raccoons as pets, ensure that children or persons with developmental disabilities do not place contaminated objects or fingers into their mouths, practice good hand hygiene after outdoor activities, and safely remove raccoon latrines on properties, paying special attention to flat surfaces such as rooftops, decks, tree stumps, or unsealed attics and other areas where raccoons prefer to defecate** (6). Property owners should also take measures to prevent raccoon infestations, including eliminating access to sources of food and water; securing trash in tightly closed containers; closing off access to basements, attics, and crawl spaces; and clearing brush and trees away from the property and roof line to discourage raccoons from sleeping or defecating nearby. Sandboxes on properties should also be covered, if possible, when not in use. Dog owners should also prevent their pets from eating raccoon feces and accessing areas with raccoon feces because dogs can also be infected and shed eggs in their feces (7). Pets should be treated with a year-round parasite prevention product that contains an intestinal dewormer effective against B. procyonis and have fecal examinations for intestinal parasites performed at least annually by a veterinarian, according to existing guidelines.††
Improving awareness among the public is critical for reducing the risk for B. procyonis infection, especially given the ubiquity of raccoons in urban settings and the challenges associated with raccoon exclusion. For clinicians, education to heighten awareness and increase recognition is needed. Any patients, especially young children or persons with developmental disabilities or pica, who have progressive neurologic deterioration and high peripheral eosinophilia or eosinophilic meningoencephalitis, should be promptly evaluated. A history of exposure to raccoons or their feces is highly suggestive but not necessary. Empiric treatment of baylisascariasis with albendazole should be considered (6).
Source link
