Caenorhabditis elegans (C. elegans)
| Characteristics | |
|---|---|
| Morphology | Species of the genus Caenorhabditis are small nematode roundworms belonging to the Rhabditidae family. They are terrestrial organisms and adult worms have elongated cylindrical bodies, tapered at both ends, with smooth skin, no segmentation, and no appendages. Caenorhabditis elegans (C. elegans) have two naturally occurring sexes, a male and a self-fertilizing hermaphrodite; females do not naturally occur. The majority of individuals are hermaphrodites. Eggs are laid within two to three hours of fertilization and hatch approximately twelve hours later. The worms develop into adults in four larval stages; this generally takes about three days when the temperature ranges from 20 to 25oC. |
| Growth Conditions | C. elegans live primarily in soil and must have a constant level of moisture and a moderate oxygen content. Worms are also found in or on rotting vegetation above ground. They feed on various types of bacteria that live in soil. |
| Health Hazards | |
|---|---|
| Host Range | Not known to infect humans |
| Modes of Transmission | Does not cause infection |
| Signs and Symptoms | Does not cause infection |
| Infectious Dose | N/A |
| Incubation Period | N/A |
| Medical Precautions/Treatment | |
|---|---|
| Prophylaxis | None available |
| Vaccines | None available |
| Treatment | No treatment needed |
| Surveillance | N/A |
| 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-1/ABSL-1 | Risk Group 1 classification is applied to C. elegans. BSL-1 standard practices are appropriate for defined and characterized strains of viable biological agents that are not known to cause disease in immunocompetent adult humans. Using best practices and procedures with no special primary or secondary barriers, other than a door, a sink for handwashing, and non-porous work surfaces that are cleanable and easy to decontaminate. |
| Spill Procedures | |
|---|---|
| Small Spills (<1 liter) | Work on C. elegans does not require use of a BSC, however if additional agents are being used alongside the organism then a BSC should be present. 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.
C. elegans is not known to cause disease or to spread via aerosols, but caution should be taken during a spill outside of a BSC that involves additional infectious agents. 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 the organism (bleach, ethanol), working from the perimeter towards the center. Allow 30 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 with soap and water for 15 minutes (open wounds, sores, etc.) |
| 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 10% bleach and 70% ethanol. |
| Inactivation | Sensitive to low temperatures, high temperatures, and desiccation |
| Survival Outside Host | The median adult survivorship in soil is 1.5 days in a laboratory setting, the median adult survivorship of wild-type worms on agar is 12 days. |
| 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 C. elegans. 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. Wash hands with soap and water after removing gloves. |
| References | |
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