Baylisascaris procyonis

Question 1

Structure

Answer 1

large roundworm of small intestine

Question 2

Definitive hosts

Answer 2

Raccoons, can be found in domestic dogs and kinkajous

Question 3

Is it zoonotic?

Answer 3

yes

Question 4

Transmission cycle

Answer 4

adult female worms produce eggs that end up in feces-> develop into infective L2 larvae in 11-14 days -> can stay in environment for years
Young raccoons ingest L2 larval eggs-> penetrate and develop within mucosa of small intestine for several weeks-> mature in 50-76 days in intestinal lumen-> can be transmitted via milk or contact with mothers fur

Question 5

Pathogenesis

Answer 5

Intermediate hosts ingest L2-> penetrate into intestinal wall-> migrate through liver to lungs-> enter pulmonary veins so can enter arterial circulation-> larval migrans-> prolonged migrations and persistence of helminth larvae in organs and tissues of infected intermediate hosts-> some larvae are encapsulated in visceral and somatic tissues-> eosinophilic granulomas
Adult raccoons-> L3 larvae from intermediate hosts develop to adults in intestinal lumen 32-38 days

Question 6

Clinical Signs

Answer 6

Raccoons are usually asymptomatic
Other species: sudden death, lethargy, depression, unkempt haircoat, circling, ataxia, tremors, weakness, paralysis, seizures, difficulty swallowing

Question 7

Pathologic Lesions

Answer 7

severe segmental reddening in small intestine, fibrinous exudate, bleeding in small intestine mucosa -> some sections have pseudomembrane that contains flocculent
-mild, diffuse cerebral atrophy

Question 8

Diagnostics

Answer 8

No good ones
necropsy findings

Question 9

Treatment

Answer 9

albendazole

Question 10

Management

Answer 10

decontamination of raccoon latrine in urban settings
control of intermediate hosts
avoid encroaching of wildlife habitats
awareness and personal cleaning protocols for public