[Title] Mysterious Flesh-Eating Parasite Spreading Locally in U.S.: CDC Report
Once thought to be primarily a risk for travelers, a deadly parasite known as Leishmania mexicana is now believed to be spreading locally through native sand flies in the southern United States, according to a recent analysis by the Centers for Disease Control and Prevention (CDC).
Leishmania mexicana, when transmitted through infected sand flies, causes skin sores that can appear weeks or even months after the initial bite. The parasite can cause long-term scarring and continue to harm its host for years.
Though treatments for the disease, medically referred to as cutaneous leishmaniasis, exist, their effectiveness remains uncertain. Many patients who initially respond to treatment are at risk of relapse. Currently, there is no vaccine available for leishmaniasis.
The discovery of Leishmania mexicana’s local spread has raised concerns among health officials, who are now striving to increase awareness about the parasite. Dr. Mary Kamb, from the CDC’s Division of Parasitic Diseases and Malaria, stated in an interview with CBS News, “This genetic information adds credence to this idea that leishmaniasis is occurring here in the United States, it’s endemic here in the United States, at least in Texas and maybe southern border states.”
The CDC’s analysis revealed a distinct genetic fingerprint associated with leishmaniasis infections in patients without any travel history. These cases indicate that the parasite is spreading locally. Despite not being a reportable disease in most U.S. states, the CDC has experienced a growing number of requests for diagnosis assistance.
Sand flies, which transmit leishmania parasites, present unique challenges for control and prevention efforts. These tiny insects, one-fourth the size of mosquitoes, do not require standing water to breed. Controlling their population is crucial in curbing the spread of the disease.
Additionally, the recent CDC analysis serves as a wake-up call to the potential arrival of a deadlier parasite, Leishmania infantum, which causes visceral leishmaniasis—a severe form of the disease. Without timely treatment, more than 90% of visceral leishmaniasis patients die. Dogs are considered the primary reservoir for this parasite, and the increase in dog arrivals from abroad has raised concerns about its spread.
Furthermore, cases of leishmania infantum have already been reported in dogs that have not traveled abroad, highlighting the risk of transmission within the United States. Dogs can transmit the parasite to sand flies or directly through contact or bites. Humans can also carry the parasite unknowingly, with blood tests suggesting that approximately 1 in 5 American soldiers deployed to Iraq developed asymptomatic infections.
As a response to these concerns, experts are developing a risk assessment tool to assist veterinarians and public health officials in managing infected dogs. The tool will consider factors such as the dog’s origin and the presence of local sand flies to determine the necessary actions, including the possibility of euthanasia.
The discovery of Leishmania mexicana’s local spread and the potential arrival of Leishmania infantum highlight the need for increased awareness and proactive measures to prevent the further spread of these flesh-eating parasites.
