Pathogen Safety Data Sheets: Infectious Substances – Mayaro virus

On this page

• Section I - Infectious agent
  • Characteristics
• Section II - Hazard identification
  • Host range
• Section III - Dissemination
• Section IV - Stability and viability
• Section V - First aid/medical
• Section VI - Laboratory hazards
• Section VII - Exposure controls/personal protection
• Section VIII - Handling and storage
• Section IX - Regulatory and other information
• References

Section I - Infectious agent

Name: Mayaro virus
Agent type: Virus

Taxonomy

Family: Togaviridae
Genus: Alphavirus
Species: Mayaro virus

Synonym or cross reference: Also known as MAYV ^{Footnote 1}, MAY virus ^{Footnote 2}, and Mayaro fever ^{Footnote 3}.

Characteristics

Brief description: Mayaro virus (MV) is a member of the genus Alphavirus within the family Togaviridae ^{Footnote 1}. It is identified as an arthropod-borne zoonotic pathogen responsible for an acute, dengue-like illness. MV consists of an envelope and a nucleocapsid, and is approximately 65-70 nm in diameter ^{Footnote 4}. It is spherical and has an icosahedral symmetry. The viral genome consists of linear, single stranded, positive-sense RNA approximately 11.5 kb long ^{Footnote 4}.

Section II - Hazard identification

Pathogenicity and toxicity: The disease caused by MV is an acute febrile illness that is non-fatal and self-limiting in general, lasting 3-5 days, with a 10% to 50% asymptomatic presentation reported. MV infection is characterized by symptoms including headache, nausea, retro-orbital pain, arthralgia, myalgia, vomiting, diarrhoea, and rash ^{Footnote 4Footnote 5Footnote 6}. Arthralgias caused by MV infection occur in approximately 20% of cases and generally include the hands, feet, and small joints of the extremities. Long-term arthralgia occurs following acute symptoms in more than 50% of infected individuals ^{Footnote 7}. Rash caused by MV infection consists of small maculopapular or micropapular isolated lesions and occurs in approximately two-thirds of confirmed cases ^{Footnote 2Footnote 3}. Mayaro fever patients have also displayed additional symptoms such as bleeding, thrombocytopenia, and jaundice ^{Footnote 8}. Sporadic infections are common ^{Footnote 5}.

Vertebrates, such as the opossum, sloth, armadillo, coati, primates, rodents, agouti, horses and donkeys, have demonstrated MV seroprevalence; however, information on the pathogenicity of the virus in animals remains limited ^{Footnote 10Footnote 11}. Experimental infection in macaques produces febrile disease lasting 4 to 5 days, which is comparable to symptoms in humans ^{Footnote 10}.

Predisposing factors: Individuals living in rural forested areas are more likely to become infected due to a greater likelihood of contact with mosquitoes carrying the virus ^{Footnote 4Footnote 10}.

Communicability: There is no evidence of direct person-to-person transmission, but MV may be transmitted between humans indirectly via mosquitoes ^{Footnote 3Footnote 11}. Transmission of MV to humans occurs through bites of infected mosquitoes ^{Footnote 3Footnote 5Footnote 12}.

Epidemiology: MV was first reported in Trinidad and Tobago in 1954 in five rural workers presenting with febrile disease ^{Footnote 13}. MV is endemic in rural areas of northern South America and the Amazon Basin ^{Footnote 5}. Several small outbreaks of MV disease have been identified among rural communities in northern Brazil and eastern Bolivia ^{Footnote 2}. Several cases of acute febrile illness have also been reported in Belterra in the state of Pará, Brazil; however, no fatalities have been directly linked to MV. Imported cases of MV disease are rare but have been reported in North Americans, French citizens and Europeans visiting South American countries ^{Footnote 13}. Men and women are equally likely to be infected with MV ^{Footnote 14}; however, the prevalence of infection increases significantly with age, with the highest rate of increase among individuals 10-19 years of age. Epidemics occur during the rainy season and end in the dry season, following the rise and fall in the mosquito population in tropical locations ^{Footnote 12}.

Host range

Natural host(s): Humans and wild vertebrates, including non-human primates, rodents, and birds ^{Footnote 11Footnote 13}. Humans have been suggested as the amplifying host of MV during MV epidemics ^{Footnote 2}; however, they are generally considered to be dead-end hosts ^{Footnote 10}. Marmosets are considered to be the amplification host for MV within forests ^{Footnote 3}.

Other host(s): Macaques, lizards ^{Footnote 10Footnote 11}.

Infectious dose: Unknown.

Incubation period: The incubation period of MV infection in humans ranges from 6 to 12 days ^{Footnote 3Footnote 4}.

Section III - Dissemination

Reservoir: Humans and wild vertebrates including non-human primates, rodents, and birds ^{Footnote 11}. Non-human primates are suspected to be the principal reservoir for maintenance of the virus ^{Footnote 12}. MV is believed to be maintained through an enzootic cycle whereby arthropod vectors transmit the virus to non-human primates and other mammals.

Zoonosis/Reverse zoonosis: Zoonosis is possible since the virus is indirectly transmitted to humans from mosquitoes ^{Footnote 3Footnote 5Footnote 11}. Airborne transmission from infected animals and/or samples has also been suggested based on accidental laboratory exposure; however, epidemiological data is lacking ^{Footnote 15}.

Vectors: Diurnal, canopy-dwelling Haemagogus spp. mosquitoes (H. janthinomys) are considered to be the main vector of MV infection ^{Footnote 3Footnote 11}. Secondary mosquito genera include Culex spp., Coquillettidia spp., Mansonia spp., Aedes spp., Psorophora spp., and Sabethes spp. ^{Footnote 12}.

Section IV - Stability and viability

Drug susceptibility: Unknown. There is no antiviral against MV ^{Footnote 13}.

Drug resistance: Unknown.

Susceptibility to disinfectants: There is no information specific to MV available; however, most enveloped viruses are generally susceptible to a number of disinfectants including phenolic compounds, hypochlorites (1% sodium hypochlorite), alcohols (70% ethanol), formaldehyde (18.5 g/L; 5% formalin in water), glutaraldehyde (2%), and iodines (0.075 g/L) ^{Footnote 16}. They may also be susceptible to lipid solvents ^{Footnote 17}.

Physical inactivation: Viruses are sensitive to moist heat and dry heat ^{Footnote 18}. They may also be sensitive to drying.

Survival outside host: Unknown.

Section V - First aid/medical

Surveillance: A patient suspected of infection should be monitored for symptoms of disease. MV can be confirmed using serological tests, polymerase-chain reaction (PCR) analysis, real time PCR, or viral isolation in tissue culture (vero cells) ^{Footnote 3Footnote 4}. Serological tests include (i) enzyme immunoassay which uses MV-infected cultured cells as the antigen, and (ii) an IgM capture enzyme-linked immunosorbent assay (ELISA) used for detecting MV antibodies ^{Footnote 9}.

Note: The specific recommendations for surveillance in the laboratory should come from the medical surveillance program, which is based on a local risk assessment of the pathogens and activities being undertaken, as well as an overarching risk assessment of the biosafety program as a whole. More information on medical surveillance is available in the Canadian Biosafety Handbook (CBH).

First aid/treatment: Supportive therapy is mainly used, since no specific drug therapy is available ^{Footnote 3}. A non-steroidal anti-inflammatory drug, such as ibuprofen, diclofenac or naproxen, can be used for pain relief and to facilitate mobility. The antimalarial drug chloroquine can be used to treat arthralgia associated with MV disease ^{Footnote 4}.

Note: The specific recommendations for first aid/treatment in the laboratory should come from the post-exposure response plan, which should be developed as part of the medical surveillance program. More information on the post-exposure response plan can be found in the CBH.

Immunization: There is no immunization currently available for MV. However, two candidate vaccines have been tested in pre-clinical trials ^{Footnote 13Footnote 19}.

Note: More information on the medical surveillance program can be found in the CBH, and by consulting the Canadian Immunization Guide.

Prophylaxis: There is no known post-exposure prophylaxis currently available for MV.

Note: More information on prophylaxis as part of the medical surveillance program can be found in the CBH.

Section VI - Laboratory hazards

Laboratory-acquired infections: At least 6 cases of laboratory-acquired infection with MV have been reported up to 1999 (15, Pedrosa et al. 2011). One case led to a laboratory technician in French Guiana developing febrile disease after being exposed to aerosolized Mayaro viral antigen ^{Footnote 15}.

Note: Please consult the Canadian Biosafety Standard (CBS) and CBH for additional details on requirements and guidelines for reporting exposure incidents.

Sources/specimens: The main source of MV is blood (serum) of infected humans and animals ^{Footnote 14}.

Primary hazards: Primary hazards when working with MV are accidental parenteral inoculation and aerosols ^{Footnote 15}.

Special hazards: None.

Section VII - Exposure controls/personal protection

Risk group classification: MVis considered to be a Risk Group 2 Human Pathogen and Risk Group 1 Animal Pathogen.

Containment requirements: The applicable CL2 requirements outlined in the CBS should be followed.

Protective clothing: The applicable CL2 requirements for personal protective equipment and clothing outlined in the CBS should be followed.

Note: Based on a local risk assessment, appropriate hand, foot, head, body, eye/face, and respiratory protection should be identified, and the PPE requirements for the containment zone should be documented in Standard Operating Procedures.

Other precautions: None.

Section VIII - Handling and storage

Spills: Allow aerosols to settle. Wearing protective clothing, gently cover the spill with absorbent paper towel and apply suitable disinfectant, starting at the perimeter and working towards the centre. Allow sufficient contact time before clean up ^{Footnote 20}.

Disposal: All materials/substances that have come in contact with the infectious agent should be completely decontaminated before they are removed from the containment zone. This can be achieved by using a decontamination method that has been demonstrated to be effective against the infectious material, such as chemical disinfectants, autoclaving, irradiation, incineration, an effluent treatment system, or gaseous decontamination ^{Footnote 20}.

Storage: The applicable CL2 or CL2-Ag requirements for storage outlined in the CBSshould be followed. Containers of infectious material or toxins stored outside the containment zone should be labelled, leakproof, impact resistant, and kept either in locked storage equipment or within an area with limited access ^{Footnote 21}.

Section IX - Regulatory and other information

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: 2018

Prepared by: Centre for Biosecurity, 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.

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Public Health Agency of Canada, 2019
Canada