One year ago, a team of skin doctors and skin pathologists at the University of Texas Southwestern Medical Center discovered nine cases of an infectious skin disease called Leishmaniasis in North Texas. The disease is common to South America, Mexico, and the Middle East, where it is sometimes called "Baghdad boil."
While the disease has been seen in troops returning from Iraq and Afghanistan, this is the first time the disease has been seen in North America among those who have no history of traveling to areas where the disease is endemic.
Leishmaniasis causes sores the size of half dollars or larger. The sores resemble boils, last for from 6-12 months and because these non-healing sores can be mistaken for staph infection, patients may be treated with several courses of antibiotics without success. Special cultures must be done to confirm the presence of the single-celled parasite known as Leishmania, to make an accurate diagnosis of leishmaniasis.
Now that a cluster of the patients have been found within close geographical proximity, North Texas doctors must wake up to the fact that the disease has become endemic to this area. The good news is that the form of leishmaniasis found in North Texas has been identified as Leishmania mexicana, the least dangerous of this family of parasites. Clinical instructor of dermatology at UT Southwestern, Dr. Kent Aftergut, referring to this type of leishmania parasite stated, "It makes skin sores, but the infection doesn't spread and become a full body disease like some of the others species of Leishmania. Usually, if patients have a normal immune system, the sores will resolve in 6 to 12 months and won't make the patients ill."
Burrowing Wood Rat
Doctors suspect that leishmaniasis begins when a sand fly bites the rodent known as the burrowing wood rat, which is a carrier of the parasite. If the sand fly should then bite a human, sores may begin to develop.
The medical community has long known to look for the disease in soldiers returning from endemic areas, but the need to treat the condition in North Texans among patients with no travel history as a new phenomenon. Dr. Aftergut is anxious to get the word out to health care professionals in the area.
Sporadic cases have been seen in South Texas for many years, but this is the first time that Texas is seeing a cluster of cases this far north. The exact reason for the move to the north is unknown, though it is believed that those who live in rural areas are at risk due to their proximity to wooded areas where the burrowing wood rat and sand flies tend to be found.
The use of insecticides, bug repellant and protective clothing when working in areas where sand flies may be present reduces the risk. There are two treatments available for leishmaniasis, though one of them is sometimes toxic to patients.
The CDC has asked doctors who find a possible case of the disease to contact them so they can offer assistance in verifying the presence of leishmaniasis.