Children are most victims of new raccoon-spread pathogen. (Severe CNS Effects and Death).
MIAMI BEACH - Baylisascaris procyonis is emerging as an important and deadly new human pathogen, particularly in children, Dr. Sheldon L. Kaplan reported at a pediatric update sponsored by Miami Children's Hospital.
There is no effective treatment, and all reported cases have resulted in severe neurologic impairment or death.
The parasite is carried by raccoons, and because they are increasing in numbers and live in most areas of the United States, the likelihood of human exposure and infection may be higher than people recognize, said Dr. Kaplan, chief of infectious diseases at Texas Children's Hospital, Houston.
Infections with B. procyonis have been confirmed in more than 90 domestic and wild ammals. Human infection typically results in severe sequelae, induding eosinophilic meningoencephalitis, and death (Emerg. Infect. Dis. 8:355-59, 2002).
The first case was identified in a 10-month-old boy in rural Pennsylvania in 1984. Since then, infection with the unusual roundworm has been confirmed in 10 other people. Raccoons, as in the Pennsylvania case, spread eggs through fecal droppings.
Although people of any age are at risk, the fecal-oral route of transmission makes young children most susceptible. The eggs hatch in the soil and become larvae. If a host other than a raccoon ingests the larvae, they migrate through tissue to the brain, eyes, and central nervous system.
No effective treatment is known. Several antihelmintic agents have been tried unsuccessfully. Therefore, awareness and prevention are paramount. The number of reported human cases is likely to increase.
"In the U.S., our housing is getting more and more out into the woods, so there are more encounters with raccoons,i' he said.
Parents should be warned not to let children play in areas where raccoons may have defecated, he said. Nine of the 11 reported cases of larval B. procyonis infection occurred in children aged 10 months to 17 years. Four died. He also advised discouraging the public from having raccoons as pets.
Diagnosis is challenging because there is no serologic test for the infection, and its symptoms closely mirror those associated with other larval nematodes, such as Toxocara canis, T cati, and Ascaris lumbricoides.
A presumptive diagnosis can be made on the basis of clinical symptoms, such as meningoencephalitis, diffuse unilateral subacute neuroretinitis, or pseudorumor, and epidemiologic evidence, such as raccoon exposure.
Radiologic evidence of white matter disease and laboratory evidence of blood or central nervous system eosinophilia also are confirmatory
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||Baylisascaris procyonis|
|Publication:||Family Practice News|
|Date:||Apr 1, 2003|
|Previous Article:||Viral culprits suspected in five new exanthems. (Resolve on Their Own).|
|Next Article:||Watch for periodic fever syndrome under age 5. (Benign but Distressing for Families).|