NAME: Vesicular stomatitis virus (VSV)
CHARACTERISTICS: A member of the Vesiculovirus genus, in the family Rhabdoviridae(3,6). VSV is a bullet-shaped, enveloped virus, approximately 70 nm in diameter and 170 nm in length(3), and has a single-stranded, negative-sense RNA genome(5,8).VSV has eight main serotypes: Indiana, New Jersey, Cocal, Alagoas, Isfahan, Chandipura, Maraba, and Piry (1,2,3,5,6,8,9).
PATHOGENICITY/TOXICITY: Most human infections with Indiana and New Jersey VSV serotypes appear to be subclinical(1,6,8). In patients that show clinical manifestations, the initial symptom is high fever that is often biphasic. Subsequent symptoms are “flu-like” including severe malaise, headaches, myalgia, arthralgia, retrosternal pain, eye aches, and nausea (1,3,6,7). Vesicle formation on the oral mucosa, lips, and nose is possible, but these are rare symptoms of vesicular stomatitis (VS) (3,6,7). Human infections with Cocal virus have not been documented (6), whereas Alagoas virus infections in humans have only been reported in Brazil, with flu-like symptoms that resolved within 3-4 days (10). Chandipura virus has only been reported in India, where it mostly infects children. Symptoms include fever, sensory disorders, convulsions, vomiting, diarrhoea, and encephalitis leading to coma and death (11). Reports on the pathogenicity of Piry virus in humans are inconsistent and virtually absent from the primary literature; however, Piry virus is closely related to Chandipura virus, based on glycoprotein sequence analysis (12). The pathogenicity of Maraba virus in humans is also not known. Isfahan virus was associated with human infections in Iran; however, the virus has not been definitively linked to human illness(13). In the laboratory, VSV has been engineered to target cancer cells or to stimulate immunity against diseases such as AIDS or influenza(8).
EPIDEMIOLOGY: VS exists in North and South America, Africa and Asia but not in central Europe(6). Serological surveys indicate that the prevalence of infection may be high among some populations in enzootic areas. For example, in a rural locality in Panama, more than 90% of the adult population is affected (3); however, the precise frequency of VS is not well established, as the disease often goes unnoticed due to its benign course.
INFECTIOUS DOSE: Unknown.
MODE OF TRANSMISSION: Bite of an infected sand fly(1,5,7,8); by direct contact with abrasions on the skin; by contact with infected domestic animals; or by inhaling aerosols via the nasopharyngeal route(1,3). The virus has also been transmitted via accidental autoinoculation or inhalation of aerosols in a laboratory setting(3,8).
COMMUNICABILITY: There is no documented evidence of person-to-person transmission of VSV.
VECTORS: Sand fly (Phlebotomus spp.) appears to be the most important vector for VSV(2,6,8). Black flies (Simuliidae)(2,5,6), midges (Culicoides spp.), mosquitoes (Aedes spp.)(2,5,8) and other diptera(2,5,6) have also been implicated.
DRUG SUSCEPTIBILITY: Unknown.
PHYSICAL INACTIVATION: Inactivated at low pH (1.5) (14), and immediately upon heating to 60 °C (15,16). VSV in stroma-free haemoglobin can also be inactivated by phototreatment (for example, with red light-emitting diode (655 nm), 1,9-dimethylmethylen blue (DMMB), or methylen blue (MB)) (16).
SURVIVAL OUTSIDE HOST: VSV can survive for 3 to 4 days in infected saliva on milking pails, mangers and hay(1).
SURVEILLANCE: Monitor for symptoms. Human VSV infections are confirmed by virus isolation from throat swabs or blood (1,2,6). Other methods of detection include PCR (1,2,6), ELISA(1,2), neutralisation(2), compliment fixation, immunofluorescence, and electron microscopy(1).
Note: All diagnostic methods are not necessarily available in all countries.
FIRST AID/TREATMENT: No specific therapy is currently available. Symptomatic treatment and prevention of secondary infections is important (6).
IMMUNIZATION: None currently available for use in humans.
PROPHYLAXIS: Good hygiene is usually sufficient to prevent the spread of VSV(6).
LABORATORY-ACQUIRED INFECTIONS: 46 recorded cases with New Jersey and Indiana viruses (with no deaths) until 1980 (17). 13 cases of laboratory infections (no deaths) due to Piry virus were also reported before 1980(18). No LAIs associated with Chandipura, Cocal, Maraba or Isfahan viruses have been reported to date.
PRIMARY HAZARDS: Exposure of skin and mucous membranes to VSV by direct contact or bite by an infected sand fly.
RISK GROUP CLASSIFICATION: Chandipura and Piry viruses are classified as Risk Group 3 human pathogens. Indiana, Cocal, Alagoas, New Jersey, Isfahan and Maraba viruses are classified as Risk Group 2 human pathogens. Vesicular Stomatitis Virus is classified as Risk Group 3 since the species includes Risk Group 3 serotypes.
CONTAINMENT REQUIREMENTS: Chandipura and Piry viruses:Containment Level 3 facilities, equipment, and operational practices for work involving infectious or potentially infectious materials, animals, or cultures. Indiana, Cocal, Alagoas, New Jersey, Isfahan and Maraba viruses: Containment Level 2 facilities, equipment, and operational practices for work involving infectious or potentially infectious materials, animals, or cultures.
PROTECTIVE CLOTHING: In Containment Level 3 laboratories: Personnel entering the laboratory should remove street clothing and jewellery, and change into dedicated laboratory clothing and shoes, or don full coverage protective clothing (i.e., completely covering all street clothing). Additional protection may be worn over laboratory clothing when infectious materials are directly handled, such as solid-front gowns with tight fitting wrists, gloves, and respiratory protection. Eye protection must be used where there is a known or potential risk of exposure to splashes(19). In Containment Level 2 laboratories: Lab coat. Gloves when direct skin contact with infected materials or animals is unavoidable. Eye protection must be used where there is a known or potential risk of exposure to splashes.
OTHER PRECAUTIONS: In Containment Level 3 laboratories: All activities with infectious material should be conducted in a biological safety cabinet (BSC) or other appropriate primary containment device in combination with personal protective equipment. Centrifugation of infected materials must be carried out in closed containers placed in sealed safety cups, or in rotors that are loaded or unloaded in a biological safety cabinet. The use of needles, syringes, and other sharp objects should be strictly limited. Open wounds, cuts, scratches, and grazes should be covered with waterproof dressings. Additional precautions should be considered with work involving animals or large scale activities (19). In Containment Level 2 laboratories: All procedures that may produce aerosols, or involve high concentrations or large volumes should be conducted in a biological safety cabinet (BSC). The use of needles, syringes, and other sharp objects should be strictly limited. Additional precautions should be considered with work involving animals or large scale activities.
SPILLS:Allow aerosols to settle and, wearing protective clothing, gently cover spill with paper towels and apply appropriate disinfectant, starting at the perimeter and working towards the centre. Allow sufficient contact time before clean up (30 min) (19).
DISPOSAL: Decontaminate all materials for disposal by steam sterilisation, chemical disinfection, and/or incineration (19).
STORAGE: Chandipura and Piry viruses: In sealed, leak-proof containers that are appropriately labelled and locked in a Containment Level 3 laboratory(19). Indiana, Cocal, Alagoas, New Jersey, Isfahan and Maraba viruses: In sealed containers that are appropriately labeled (19).
REGULATORY INFORMATION: The import, transport, and use of pathogens in Canada is regulated under many regulatory bodies, including the Public Health Agency of Canada, Health Canada, Canadian Food Inspection Agency, Environment Canada, and Transport Canada. Users are responsible for ensuring they are compliant with all relevant acts, regulations, guidelines, and standards.
UPDATED: January 2012.
PREPARED BY: Pathogen Regulation Directorate, Public Health Agency of Canada.
Although the information, opinions and recommendations contained in this Pathogen 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.
Public Health Agency of Canada, 2012