Baylisascariasis: A Potential Local Threat Joshua Sabey BIOL 4800

Emerging Diseases HINI (Swine Flu) Avian influenza (Bird Flu) Severe acute respiratory syndrome (SARS) West Nile virus Bovine Spongiform Encephalopathy (Mad Cow) Staphylococcus aureus (Antibiotic Resistance) Plasmodium (Malaria) Baylisascaris procyonis (Raccoon Ascaris)

Baylisascaris procyonis Eggs Larvae Adults Nematode Dioecious Thick cuticle

Life-Cycle

Life-Cycle Specifics Final host is Raccoon. Has a wide range of intermediate hosts including birds, squirrels, woodchucks, and rabbits. Larvae can also infect humans and cause major problems.

Raccoon Range

Raccoon Range Expansion Raccoon harvest 1000 pelts or more MB = 1967 SK = 1972 AB = 1983

Expansion Reasons 1. Anthropogenic Resources Food availability (Garbage and food crops). Den availability (Trees in parks or yards, chimneys, and attics). 2. Global Warming Longer growing season = more food. Mild winters = increased hibernation survival.

Raccoon Problems Average 20,000 eggs per gram of feces. Also common carriers of rabies and canine distemper.

The Urban Raccoon

Raccoon Latrines

Prevalence in Urban Areas Percentage of yards surveyed that had latrines: Chicago = 51%, San Jose = 49%. Percentage of latrines surveyed that were infective: Winnipeg = 50%, San Jose = 53%. Percentage of captured individuals that were infected: Winnipeg = 50%. Some areas in Florida have an infection rate of up to 82%.

Pathology CLM VLM OLM Children are at highest risk by playing in yards and parks.

Pathology Baylisascaris procyonis larval migration is more aggressive. Larvae are larger and grow during migration. Results in more damage to tissues. Releases toxic proteins causing inflammation. CLM = intense itching. VLM = abdominal pain. OLM = partial or total loss of vision.

NLM Initial Picture 2 Weeks Later 6 Weeks Later Encephalitis: inflammation of the brain. Progressive neurological decline. Treatment does not prevent damage.

Treatment OLM are treated through surgical removal or direct laser photocoagulation. All other LM are treated with antihelminthic medications. Despite treatment, there are no documented neurologically intact survivors of NLM. 40% of documented cases were fatal. 73% of documented cases were children under 3.

Conclusions Raccoon range expansion North and West into Canada is making baylisascariasis a potential local problem. Increased Raccoon populations in urban areas are increasing human exposure rates. Since treatment is not effective, emphasis should be put on prevention of exposure.

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