NAME: Wuchereria bancrofti
SYNONYM OR CROSS REFERENCE: Bancroftian filariasis, filariasis, elephantiasis
CHARACTERISTICS: Filarial nematode, adults are white, threadlike worms; females (80-100 mm in length, 0.2-0.3 mm in width) usually twice size of male, resides in lymphatics; microfilaria are 250-300 µm long and 7-9 µm in width
PATHOGENICITY: Clinical manifestation varies from asymptomatic to a variety of symptoms including recurrent filarial fever, lymphadenitis and retrograde lymphangitis; chronic signs includes hydrocele, chyluria and elephantiasis of the limbs, breast and genitalia; those with tropical pulmonary eosinophilia syndrome, manifested by nocturnal asthma, chronic interstitial lung disease, recurrent low-grade fever
EPIDEMIOLOGY: Endemic in most of the warm humid regions of the world, including Latin America (scattered foci in Brazil, Surinam, French Guiana, Haiti, Dominican Republic and Costa Rica), Africa, Asia and the Pacific Islands; common in urban areas where conditions favor vectors breeding
HOST RANGE: Humans
INFECTIOUS DOSE: Not known
MODE OF TRANSMISSION: Usually by the bite of an infectious mosquito (Culex quinquefasciatus, Anopheles gambiae, An. funestus, Aedes polynesiensis, Ae. scapularis and Ae. pseudoscutellaris)
INCUBATION PERIOD: Variable; allergic inflammatory manifestations can appear a month after infection; microfilariae appears in the blood by 6 to 12 months and may persist for 5 to 10 years or longer
COMMUNICABILITY: Not directly transmitted from person-to-person; humans can infect mosquitoes if microfilariae are present in the blood; mosquito becomes infective 12 to 14 days after a blood meal
RESERVOIR: Humans
ZOONOSIS: Mosquito as developmental reservoir and vector
VECTORS: Mosquito (Culex quinquefasciatus, Anopheles gambiae, An. funestus, Aedes polynesiensis, Ae. scapularis, Ae. pseudoscutellaris)
DRUG SUSCEPTIBILITY: Sensitive to diethylcarbamazine, ivermectin
SUSCEPTIBILITY TO DISINFECTANTS: All infectious stages are susceptible to 1% sodium hypochlorite, 2% glutaraldehyde
PHYSICAL INACTIVATION: Sensitive to freezing
SURVIVAL OUTSIDE HOST: Not known
SURVEILLANCE: Monitor for symptoms; confirm by microscopic demonstration of microfilariae in peripheral blood; PCR detection method is available
FIRST AID/TREATMENT: Administer appropriate drug therapy
IMMUNIZATION: None available
PROPHYLAXIS: Diethylcarbamazine
LABORATORY-ACQUIRED INFECTIONS: None reported to date
SOURCES/SPECIMENS: Blood
PRIMARY HAZARDS: Accidental parenteral inoculation; droplet exposure of the infective stages of the parasite to the mucous membranes
SPECIAL HAZARDS: None
CONTAINMENT REQUIREMENTS: Biosafety level 2 practices and containment equipment for all activities involving the infective stages of the parasite and potentially infectious body fluids or tissues
PROTECTIVE CLOTHING: Laboratory coat; gloves when skin contact with infected materials is unavoidable
OTHER PRECAUTIONS: Frequent hand washing
SPILLS: Allow aerosols to settle; wearing protective clothing gently cover the 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, incineration, chemical disinfection
STORAGE: In sealed containers that are appropriately labeled
Date prepared: January, 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