First human case of insect transmission of Chagas parasite identified

in Louisiana by Loyola University New Orleans professor

Not a public health concern

(New Orleans)—Loyola biology professor Patricia Dorn, Ph.D., in collaboration with Dawn Wesson, Ph.D., of Tulane University Health Sciences Center and Loyola undergraduate student Leon Perniciaro discovered the first human case of insect-transmitted Chagas parasite in Louisiana and sixth ever in the United States. The discovery was made in July 2006 in a rural area of New Orleans.

The discovery was made after a resident brought insects to the attention of a pest control operator who identified them as kissing bugs. After researching the bug on the Internet, the resident realized the potential for Chagas transmission. Because Dr. Dorn is known in this area as the expert on Chagas disease and her ongoing international research in this field, she was contacted to administer the test for the Chagas parasite and further investigate this situation. Both residents were tested at Loyola and the Centers for Disease Control and one resident tested positive for the exposure to the Chagas parasite. Many insects have been collected in the house and the nearby building and studies carried out by Dr. Dorn and her students over the last several months indicate that more than half of the insects tested carry the Chagas parasite.

What does this mean and what are the implications for the general public.

Although we have known for many years that there is an endemic cycle in wild animals in Louisiana (approximately 30 – 40 percent of armadillos and opossums are infected with the Chagas parasite), this is the first report of infection in a human with the Chagas parasite by an insect in Louisiana. This is not a widespread public health concern since the person was living in a rural area in a very open house with numerous entry points for insects and no air conditioning and most people in Louisiana live in much less open homes.

Dr. Dorn has spent 14 years studying Chagas disease, mostly in Guatemala. She is continuing her work on the insects that carry the Chagas parasite in Central America and Mexico and working with researchers at the LSU Veterinary School on Chagas in dogs in Louisiana.

Dr. Dorn’s scholarly paper on this significant finding will soon be published in the journal of Emerging Infectious Diseases which is published by the Centers for Disease Control. She also presented her findings at the annual meeting of American Association of Tropical Medicine and Hygiene in Atlanta in November 2006. For a brief summary of Chagas disease and its natural transmission in the United States go to the following link on Dr. Dorn’s website: http://chn.loyno.edu/biology/bios/dorn-chagasresearch.html