Flesh Eating Parasite Warning Issued By CA Health Officials
The rare parasite feeds on living tissue and has been seen in international travelers and within 70 miles of the southern border.
Albert Gregory,Patch Staff
California health officials are warning residents about the appearance of a parasitic fly that feeds off of living flesh in humans and animals.
The California Department of Health said it is called the New World Screwworm, a rare previously eradicated parasite with increased detection in Mexico and other parts of Central America.
The U.S. Department of Health recently identified one in a U.S. resident who had traveled from El Salvador.
"California Department of Health is closely monitoring the increased detections of New World Screwworm (NWS) in southern Mexico and Central America. NWS may be directly introduced to California via an infested traveler or animal, or by continued spread of the NWS fly across Mexico and eventually into California," state health officials warned. "Since NWS introduced into California could propagate and spread, rapid identification, investigation, and communication will be critical for an effective response. "
The CDC said NWS infestations are characterized by significant pain. Individuals suffering from an NWS infestation may observe maggots in or around open wounds, as well as in their nose, eyes or mouth.
Other signs are painful, foul-smelling, or unhealing open sores, and bleeding from these sores, the CDC reported.
Individuals at higher risk for NWS are those in areas with the flies who have open wounds, weakened immune systems, medical conditions causing bleeding or open sores, or who sleep outdoors, especially during the day.
Even small wounds can attract females, who lay 200 to 300 eggs at a time and up to 3,000 in their 10 to 30 day lifespan, the CDC reported.
The CDC recommended to prevent NWS infections in areas where the flies are present, keep open wounds clean and covered, and prevent insect bites. Also, wear loose-fitting, long-sleeved clothing and socks, use EPA-registered insect repellent, and treat clothing and gear with 0.5 percent permethrin. Additionally, sleep indoors with screened windows or under a bed net/screened tent outdoors.
Flesh Eating Parasite Warning Issued By CA Health Officials
The CDC said if anyone finds maggots or eggs on their body, contact a healthcare provider immediately. Do not attempt to remove them yourself or dispose of them in the trash, as this could lead to the spread of NWS. If maggots or eggs fall out, collect them in a leak-proof container with rubbing alcohol and bring them to your provider. Your healthcare provider will remove each maggot, sometimes surgically, the CDC said.
It has not been found in California livestock or any other animals, health officials reported.
CDH officials said individuals who traveled to areas known to have the parasite in the last 10 days should contact a healthcare provider if they experience myiasis, a parasitic infection caused by the fly larvae that infests living tissue
Providers identifying myiasis in such patients should inquire about recent travel to those countries and notify their local health department, officials said.
New World Screwworm, eradicated in the U.S. in 1966, is now primarily located in South America, Cuba, Haiti and the Dominican Republic. Since 2023, it has spread north through Central America and into southern Mexico, where it has been identified in seven states, CDH officials said.
There have been over 720 human cases, including six deaths, and more than 111,000 animal cases in these regions, according to the CDH.
A new case of New World Screwworm has been confirmed by Mexico's National Service of Agro-Alimentary Health, Safety, and Quality, the USDA reported. The case was identified in a location less than 70 miles from the U.S.-Mexico border.
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