Chikungunya Virus (CHIKV)

Characteristics
Morphology	A member of the Togaviridae family and Alphavirus genus. Specifically belonging to the Semliki Forest serological complex. Chikungunya virus (CHIKV) is a spherical enveloped virion that measures 60 to 70 nm in diameter and contains a single-stranded, positive-sense RNA genome.
Growth Conditions	Huh7 (hepatocytes), C2C12 (myoblasts), SVG-A (glial cells), dermal fibroblasts, and mosquito cell lines

Health Hazards
Host Range	Humans, non-human primates, rodents, and birds.
Modes of Transmission	Aedes aegypti and Aedes albopictus mosquito bites (during the day and at night). In rare cases, CHIKV can be transmitted from mother to newborn at time of birth. Inhalation of aerosolized CHIKV in the lab may lead to infection.
Signs and Symptoms	Most common: Fever and joint pain; other symptoms may include: headache, muscle pain, joint swelling, or rash. Does not often result in death, but can be severe and disabling. Most patients feel better within a week. In some people, the joint pain may persist for months.
Infectious Dose	Unknown
Incubation Period	Usually 2-3 days (1-12 day range)

Medical Precautions/Treatment
Prophylaxis	Avoid mosquito bites. Use insect repellent (containing DEET, picaridin, IR3535, and oil of lemon eucalyptus and paramenthane-diol products) when travelling to areas with CHIKV. Wear long sleeves and pants. Stay in places with air conditioning or that use window and door screens.
Vaccines	None publically available
Treatment	Most CHIKV infections require only care to help relieve symptoms. Infected individuals should prevent mosquito bites for the first week of your illness to prevent transmission to mosquitoes.
Surveillance	Monitor for symptoms. Confirmation is via detection of CHIKV in blood samples.
GWU Requirements	Report all incidents to the Office of Risk Management as well as the Office of Research Safety (ORS) IMMEDIATELY FOLLOWING THE OCCURRENCE.

Containment
BSL-3	Risk Group 3 classification is applied to CHIKV. Containment Level 3 facilities, equipment, and operational practices for work involving infectious or potentially infectious material. All activities with infectious material should be conducted in a HEPA-filtered 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 unloaded in a biological safety cabinet. Open wounds, cuts, scratches, and grazes should be covered with waterproof dressings.
ABSL-3	All work involving infectious or potentially infectious material should follow the same guidelines as stated above. Additional precautions should be considered with work involving animals.

Containment

BSL-3

Risk Group 3 classification is applied to CHIKV. Containment Level 3 facilities, equipment, and operational practices for work involving infectious or potentially infectious material. All activities with infectious material should be conducted in a HEPA-filtered 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 unloaded in a biological safety cabinet. Open wounds, cuts, scratches, and grazes should be covered with waterproof dressings.

ABSL-3

All work involving infectious or potentially infectious material should follow the same guidelines as stated above. Additional precautions should be considered with work involving animals.

Spill Procedures
Small Spills (<1 liter)	If the spill occurred inside a biological safety cabinet, close the sash and allow the cabinet to operate for 15 minutes before continuing with the spill cleanup. CHIKV has no known cases of aerosol transmission, but extra caution should still be taken during a spill outside of a BSC. Leave the room immediately and allow the aerosols to dissipate for 15 minutes. Notify others working in the lab. Don appropriate PPE. Cover area of the spill with paper towels or any absorbent material and apply an EPA registered disinfectant effective against enveloped viruses (alcohols, bleach, and quaternary ammonium compounds), working from the perimeter towards the center. Allow 15-20 minutes of contact time before disposal and cleanup of spill materials.
Large Spills	Alert lab personnel in the laboratory to the spill and keep people out of the area to prevent spread of the contamination. Check if you have been contaminated or if any of your PPE has been breached. If so follow exposure procedures. Remove any contaminated clothing and place it the biohazard waste. Wash your hands and post a sign on the door. Notify your supervisor of the incident and call ORS (4-8258) for assistance. If the situation involves an imminently life-threatening injury or has catastrophic potential, call 911.

Spill Procedures

Small Spills (<1 liter)

If the spill occurred inside a biological safety cabinet, close the sash and allow the cabinet to operate for 15 minutes before continuing with the spill cleanup.

CHIKV has no known cases of aerosol transmission, but extra caution should still be taken during a spill outside of a BSC. Leave the room immediately and allow the aerosols to dissipate for 15 minutes. Notify others working in the lab. Don appropriate PPE. Cover area of the spill with paper towels or any absorbent material and apply an EPA registered disinfectant effective against enveloped viruses (alcohols, bleach, and quaternary ammonium compounds), working from the perimeter towards the center. Allow 15-20 minutes of contact time before disposal and cleanup of spill materials.

Large Spills

Alert lab personnel in the laboratory to the spill and keep people out of the area to prevent spread of the contamination. Check if you have been contaminated or if any of your PPE has been breached. If so follow exposure procedures. Remove any contaminated clothing and place it the biohazard waste. Wash your hands and post a sign on the door. Notify your supervisor of the incident and call ORS (4-8258) for assistance. If the situation involves an imminently life-threatening injury or has catastrophic potential, call 911.

Exposure Procedures
Mucus Membrane	Flush eyes, mouth or nose for 15 minutes at eyewash station.
Other Exposure	Wash area with soap and water for 15 minutes.
Reporting	Report ALL injuries to the PI immediately and reported to the Office of Risk Management at [email protected] IMMEDIATELY FOLLOWING THE OCCURRENCE. Exposures that involve a bloodborne-pathogen or recombinant DNA also need to be reported to the Office of Research Safety at [email protected]. If the injury requires immediate medical attention, call GWPD at 202-994-6111 or call 911.
Medical Monitoring	Seek immediate medical evaluation, treatment, and post exposure follow-up at the Employee Health Office at GWU Hospital (900 23rd St., NW, Suite G-1090, Phone: 202-715-4275). Students should go to the Students Health Office at Marvin Center. After hours treatment can be received at the GWU hospital emergency room.

Stability
Disinfection	Susceptible to 70% Ethanol, 10% bleach, and 2% glutaraldehyde. Quaternary ammonium compounds can be used as well
Inactivation	Sensitive to desiccation and temperatures above 58°C.
Survival Outside Host	Unknown

Personal Protective Equipment (PPE)
Minimum PPE Requirements	At minimum, personnel are required to don gloves, closed toed shoes, lab coat, and appropriate face and eye protection prior to working with CHIKV. Additional PPE may be required depending on lab specific SOPs.
Additional Precautions	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.

References
CDC (https://www.cdc.gov/adenovirus/) Evaluation of a range of mammalian and mosquito cell lines for use in Chikungunya virus research (https://www.nature.com/articles/s41598-017-15269-w) Overview on Chikungunya Virus Infection (Review Article) (https://www.frontiersin.org/articles/10.3389/fmicb.2021.744164/full) Canadian PHAC (https://www.canada.ca/en/public-health/services/laboratory-biosafety-bi…)

References