MATERIAL SAFETY DATA SHEET - INFECTIOUS SUBSTANCES

SECTION I - INFECTIOUS AGENT

NAME: Hepatitis E virus

SYNONYM OR CROSS REFERENCE: HEV, enterically transmitted non-A non-B hepatitis (ET-NANB), epidemic non-A non-B hepatitis, faecal-oral non-A non-B hepatitis, A-like non A non B hepatitis

CHARACTERISTICS: Single stranded positive sense RNA, non-enveloped, 27-34 nm, resembling caliciviruses and togaviruses (rubella virus); serologically related smaller (27-30 nm) particles are often found in faeces; hepatitis E virus has been assigned to genus "hepatitis E like virus"

SECTION II - HEALTH HAZARD

PATHOGENICITY: Symptoms include jaundice, anorexia, hepatomegaly, abdominal pain and tenderness, nausea and vomiting and fever; mortality of HEV infection has been reported to be as high as 1%; however, in pregnant women, with each passing trimester the mortality rate may reach 20%; this is the most severe hepatitis in pregnancy of all of the recognized hepatitis viruses

EPIDEMIOLOGY: Outbreaks and sporadic cases of HEV have occurred over a large geographic area, most notably in regions with poor sanitation; there have been several food-borne epidemics, but the majority of confirmed HEV infections have been associated with the consumption of fecally contaminated water; the attack rate is highest in young adults; in the USA, Canada and most other industrialized countries, HEV infections have been reported only from travellers returning from HEV-endemic areas; documented outbreaks have occurred in India, Burma (Myanmar), Iran, Bangladesh, Ethiopia, Nepal, Pakistan, Central Asian Republics of the former Soviet Union, Libya, Mexico, Algeria, Somalia, China and Indonesia; hepatitis caused by HEV is clinically indistinguishable from hepatitis A disease

HOST RANGE: Humans, primates (infection of chimpanzees, macaques, African Green monkeys, marmosets, owl monkeys, and squirrel monkeys), pigs, rodents and domestic chickens

INFECTIOUS DOSE: Unknown

MODE OF TRANSMISSION: Faecal-oral route; ingestion of contaminated water (most commonly documented vehicle of transmission; person-to-person transmission appears to be uncommon; secondary household cases are not common during outbreaks; potential exists for food-borne transmission

INCUBATION PERIOD: Two to 9 weeks, mean 26-42 days; resolution in all cases of HEV infection

COMMUNICABILITY: Unknown; HEV has been detected in stools 14 days after the onset of jaundice and approximately 4 weeks after oral ingestion of contaminated water and persists for about 2 weeks; maximal HEV shedding in feces occurs during the incubation period and during the early acute stage of the disease

SECTION III - DISSEMINATION

RESERVOIR: Unknown; occurrence of sporadic cases may maintain transmission during interepidemic periods, but a non-human animal reservoir for HEV is possible but not known; recent studies suggest a reservoir may exist in domestic animals, including swine

ZOONOSIS: Zoonotic spread of HEV is not known; HEV has been detected in swine, rats and chickens

VECTORS: None

SECTION IV - VIABILITY

DRUG SUSCEPTIBILITY: Unknown

SUSCEPTIBILITY TO DISINFECTANTS: Unknown; basic measures for the disinfection of hepatitis A virus (1% sodium hypochlorite, glutaraldehyde, formaldehyde)

PHYSICAL INACTIVATION: Unstable when stored at temperatures between -70° C and 8° C; stable in liquid nitrogen; basic measures for the physical inactivation of hepatitis A virus (susceptible to 56° C for at least 30 minutes and radiation); susceptible to 70° C after 4 minutes

SURVIVAL OUTSIDE HOST: Unknown; likely similar to hepatitis A virus (survives in water and sewage for long periods); serum storage at -70° C, feces storage at -120° C is preferred

SECTION V - MEDICAL

SURVEILLANCE: Monitor for symptoms; confirmation by serological and epidemiological characterization of the outbreak and by exclusion of hepatitis A and B viruses.

FIRST AID/TREATMENT: Rest

IMMUNIZATION: None available

PROPHYLAXIS: No specific treatment available

SECTION VI - LABORATORY HAZARDS

LABORATORY-ACQUIRED INFECTIONS: None reported

SOURCES/SPECIMENS: Feces of infected humans, primates and pigs

PRIMARY HAZARDS: Ingestion of feces, stool specimens and other contaminated materials; importance of aerosol exposure has not been demonstrated

SPECIAL HAZARDS: None

SECTION VII - RECOMMENDED PRECAUTIONS

CONTAINMENT REQUIREMENTS: Containment level 2 practices for activities with infected materials; animal pathogen containment level 2 for activities using naturally or experimentally infected animals

PROTECTIVE CLOTHING: Laboratory coat; gloves when direct contact with infectious materials is unavoidable; gloves and gown for work in biosafety cabinet

OTHER PRECAUTIONS: Animal care personnel should wear gloves and take other appropriate precautions to avoid possible faecal-oral exposure

SECTION VIII - HANDLING INFORMATION

SPILLS: Allow aerosols to settle, wearing protective clothing, gently cover spill with paper towel and apply appropriate disinfectant (the same disinfectant used for hepatitis A spills, 1% sodium hypochlorite, would be appropriate), starting at perimeter and working towards the centre; allow sufficient contact time (30 minutes) before clean up

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

STORAGE: In sealed containers that are appropriately labelled

SECTION IX - MISCELLANEOUS INFORMATION

Date prepared: May, 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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