Acanthamoeba castellanii Agent Information Sheet
Boston University
Research Occupational Health Program (ROHP)
617-358-7647
Agent
Acanthamoeba is a parasite that given the opportunity can threaten sight and cause encephalitis.
Disease/Infection
Acanthamoeba is a parasite that is found commonly in water, soil and air. Acantamoeba Castellanii is one of eight species that has been found to cause Acanthamoeba Keratitis, a potentially blinding infection of the cornea. Most infections occur in contact lens wearers.
Pathogenicity
Only in eye or rare systemic infection especially in immunocompromised persons. The pathogenesis of Acanthamoeba tends to be complex depending on the parasite, host, and environmental factors.
Biosafety Information
Risk Group/BSL
Risk Group 2
Biosafety Level 2
Modes of Transmission
| Transmission | |
| Skin Exposure | Small risk of transmission |
| Mucous Membrane Exposure splash to eye(s), nose or mouth | Small risk of transmission |
| Inhalation | Small risk of transmission. Development of hypersensitization with frequent exposure to aerosolized antigen. |
| Ingestion | Yes, ingestion of eggs or larvae would be the primary route of infection |
Host Range/Reservoir
Lives in soil and fresh water. Immunocompromised persons should be counseled about risks associated with working this this parasite.
Symptoms
Visual disturbance, photophobia, tearing, and pain
Incubation Period
Unclear, parasite
Viability
Lives in nature
Survival Outside Host
Yes, can survive for years under adverse conditions.
Information for Lab Workers
Laboratory PPE
Wear gloves, gown, surgical mask, safety glasses, or face shield if splash anticipated.
Containment
Work done under BSL-2 precautions
In Case of Exposure/Disease
- For injuries in the lab which are major medical emergencies (heart attacks, seizures, etc…):
- Medical Campus: call or have a coworker call the Control Center at 617-414–4144.
- Charles River Campus: call or have a coworker call campus security at 617-353-2121.
You will be referred to or transported to the appropriate health care location by the emergency response team. - For lab exposures (needle sticks, bite, cut, scratch, splash, etc…) involving animals or infectious agents, or for unexplained symptoms or illness call the ROHP 24/7 hour number (1-617-358-ROHP (7647); or, 8-ROHP (7647) if calling from an on-campus location) to be connected with the BU Research Occupational Health Program (ROHP) medical officer. ROHP will refer you to the appropriate health care location.
- Under any of these scenarios, always inform the physician of your work in the laboratory and the agent(s) that you work with.
- Provide the wallet-size agent ID card to the physician.
Vaccination
No vaccine and no known post exposure prophylaxis available.
Information for First Responders/Medical Personnel
Public Health Issues/PPE
Standard precautions with hand hygiene and use of gloves when responding to an incident.
After Exposure
Irrigate eye for 15 minutes.
In Case of (suspected) Illness
Contact Research Occupational Health Program.
Other guidance for outside providers
Public health officials should be notified if an exposure.
Diagnosis/Surveillance
Opthalmalogy evaluation, culture or detection of organism, cysts, or trophozoites.
First Aid/Post Exposure Prophylaxis
Wash hands, flush eyes immediately at eye wash station for at least 10-15 minutes and remove contact lenses.
Treatment
Refer to Ophthalmology. Infections with this parasite may be difficult to treat regardless of the immune status of the host. Early diagnosis is key. For eyes, treatment regimen is usually a topical cationic antiseptic agent with or without a diamidine such as propamidine (0.1%) or hexamidine (0.1%). The duration of therapy may last six months to a year. Pain control can be helped by topical cyclopegic solutions and oral nonsteroidal medications. The use of corticosteroids to control inflammation is controversial. Penetrating keratoplasty may help restore visual acuity.
References
Biosafety in Microbiological and Biomedical Laboratories (BMBL) 5th Edition. US Government Printing Office, Washington, 2007.
Control of Communicable Diseases Manual. David L. Heymann. Washington DC, USA: American Public Health Association Press, 19th edition 2008
CDC Acanthamoeba Keratitis Associated with Contact Lens. MMWR 1986;35:405-8.
https://www.cdc.gov/labs/pdf/SF__19_308133-A_BMBL6_00-BOOK-WEB-final-3.pdf
Khan NA. Pathogenesis of Acanthamoeba infections. Microb Pathog. 2003 Jun;34(6):277-85
http://www.cdc.gov/parasites/acanthamoeba/health_professionals/acanthamoeba_keratitis_hcp.html
Revised: 12/14/2015