MATERIAL SAFETY DATA SHEET - INFECTIOUS SUBSTANCES

SECTION I - INFECTIOUS AGENT

NAME: Toxocara canis, Toxocara cati

SYNONYM OR CROSS REFERENCE: Toxocariasis, visceral larva migrans, larva migrans visceralis, ocular larva migrans

CHARACTERISTICS: Nematode, helminth, larvae are 400 µm X 20 µm; adults females are 5 to 18 cm long and adult males 4 to 10 cm long; eggs are about 85 µm X 75 µm with a thick brown shell

SECTION II - HEALTH HAZARD

PATHOGENICITY: Two distinct larva migrans infection can occur: visceral larva and ocular larva migrans, both due to the systemic migration of the larval form of the helminth; visceral larva migrans is characterized by hypereosinophilia, hepatosplenomegaly, pneumonitis, fever, and hyperglobulinemia, symptoms depends on the site and extent of larval migration; ocular larva migrans (endophthalmitis) symptoms includes leukokoria, loss of vision in the affected eye, eye pain and strabismus. Disease is rarely fatal.

EPIDEMIOLOGY: Worldwide; eggs are ubiquitous in the soil wherever dogs and cats defecate; common in preschool children with a history of dirt-eating; ocular disease more common in school-age children; increasingly recognized in humans; T. canis infections are much more prevalent

HOST RANGE: Dogs and cats are the definitive hosts for T. canis and T. cati respectively; humans and other mammals are accidental hosts for both parasites

INFECTIOUS DOSE: Not known

MODE OF TRANSMISSION: By direct or indirect transmission of eggs from contaminated soil to the mouth by eating raw, unwashed vegetables and dirt (children); may also be contracted by eating raw infected tissue such as the liver of chickens, sheep, cattle

INCUBATION PERIOD: Varies from weeks to months depending on the intensity of the infection. Eggs require 1-3 weeks incubation in optimal conditions to become infective.

COMMUNICABILITY: Not directly transmitted from person-to-person

SECTION III - DISSEMINATION

RESERVOIR: T. canis in dogs; T. cati in cats

ZOONOSIS: Yes - disease transmitted by contaminated feces of dogs and cats

VECTORS: None

SECTION IV - VIABILITY

DRUG SUSCEPTIBILITY: Sensitive to antihelminths diethylcarbamazine, thiabedazole, mebedazole, albedazole

SUSCEPTIBILITY TO DISINFECTANTS: Susceptible to 1% sodium hypochlorite, 2% glutaraldehyde

PHYSICAL INACTIVATION: Eggs are sensitive to drying

SURVIVAL OUTSIDE HOST: Eggs can remain viable in soil for many months

SECTION V - MEDICAL

SURVEILLANCE: Monitor for symptoms; confirm by ELISA testing, microscopic demonstration of eggs in tissue samples

FIRST AID/TREATMENT: Administration of appropriate drug therapy

IMMUNIZATION: None available

PROPHYLAXIS: None available

SECTION VI - LABORATORY HAZARDS

LABORATORY-ACQUIRED INFECTIONS: None reported to date

SOURCES/SPECIMENS: Blood and blood products; feces; ocular tissues

PRIMARY HAZARDS: Ingestion; contamination of mucous membranes; skin penetration of larvae

SPECIAL HAZARDS: Avoid the generation of aerosols when working with infected laboratory animals; avoid contact with contaminated feces

SECTION VII - RECOMMENDED PRECAUTIONS

CONTAINMENT REQUIREMENTS: Biosafety level 2 practices and containment for activities involving the infective stage of the parasite, infectious body tissues and fluids

PROTECTIVE CLOTHING: Laboratory coats; gloves when skin contact with infectious materials is unavoidable

OTHER PRECAUTIONS: Good personal hygiene and frequent hand washing

SECTION VIII - HANDLING INFORMATION

SPILLS: Allow aerosols to settle; wearing protective clothing, gently cover spill with absorbent paper towel and apply 1% sodium hypochlorite, starting at the perimeter and working towards the center; allow sufficient contact time (30 min) before clean up

DISPOSAL: Decontaminate all wastes before disposal; steam sterilization, chemical disinfection, incineration

STORAGE: In sealed containers that are appropriately labelled

SECTION IX - MISCELLANEOUS INFORMATION

Date prepared: March, 2001

Prepared by: Office of Laboratory Security, PHAC

Although the information, opinions and recommendations contained in this Material Safety Data Sheet are compiled from sources believed to be reliable, we accept no responsibility for the accuracy, sufficiency, or reliability or for any loss or injury resulting from the use of the information. Newly discovered hazards are frequent and this information may not be completely up to date.

Copyright ©
Health Canada, 2001

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