The Chagas disease parasite, transmitted to humans by triatomine bugs, remains a leading cause of heart and digestive disease in Latin America. Pesticide spraying has effectively halted transmission in most of southern South America, especially where the bugs live exclusively inside houses. In Mesoamerica, bugs living in the forest readily reinfest treated houses. In addition, one of the main species of insect that transmits Chagas in Mesoamerica, Triatoma dimidiata, although it looks similar in different localities, may consist of genetically distinct populations, even different species, which differ in how efficiently they transmit the parasite: characteristics which confound control efforts. Nuclear and mitochondrial DNA were analyzed to characterize different populations of T. dimidiata from Mexico and Central America. Both the nuclear and mitochondrial DNA show that there is a very distinct population of T. dimidiata, perhaps even a different species, that lives in very close proximity with other T. dimidiata in Mexico and Guatemala. The nuclear DNA divides the remaining T. dimidiata into three additional genetically distinct groups. However, the mitochondrial DNA does not distinguish these additional groups. This study helps inform control efforts by showing where genetically distinct populations of T. dimidiata occur.

Researchers have found living together the known carrier species for the Chagas disease-causing parasite Triatoma dimidiata (also known as "kissing bugs") and a cryptic species that looks the same — but is genetically distinct from — the known carrier species. The two species haven't interbred for as many as 5 million years, according to a report published March 10 in the open-access journal PLoS Neglected Tropical Diseases. Researchers with Loyola University New Orleans (United States), University of Wisconsin-Madison (United States), University of San Carlos (Guatemala), and Universidad Autónoma de Yucatán (Mexico) also describe the first finding of the cryptic species in Belize. By examining the DNA of kissing bugs from throughout Mexico and Central America, the research team showed that the two species co-exist in the same towns and rural areas although they do not interbreed. "It will be important to understand what is keeping them separated," says Patricia Dorn, one of the lead authors of the study. Chagas disease remains the leading cause of parasitic illness in Latin America, with approximately 10 million people infected. "The best hope in curbing Chagas disease lies with controlling the kissing bugs that spread the parasite," Dorn says.

The first comprehensive survey of global spending on neglected disease R&D, published in this week's PLoS Medicine, finds that just over $US 2.5 billion was invested into R&D of new products in 2007, with three diseases—HIV/AIDS, TB, and malaria—receiving nearly 80% of the total. However, the survey finds that many neglected diseases, responsible for killing millions of people in developing countries, are significantly underfunded. Researchers from The George Institute report that while HIV/AIDS, TB and malaria collectively received the majority of R&D funding, other diseases and disease categories each received less than 5% of global funding. Sleeping sickness, leishmaniasis and Chagas disease collectively received only 4.9% of total global funding; the diarrhoeal illnesses surveyed collectively received 4.5% of global funding; the helminth (worm) infections received 2%; and bacterial pneumonia and meningitis received only 1.3%. Five diseases - leprosy, Buruli ulcer, trachoma, rheumatic fever, and typhoid and paratyphoid fever – each received less than $10 million or 0.4% of total global investment. For many of these diseases, funding was not enough to create even one new product.

In the United States, there is a largely hidden burden of diseases caused by a group of chronic and debilitating parasitic, bacterial, and congenital infections known as the neglected infections of poverty. Like their neglected tropical disease counterparts in developing countries, the neglected infections of poverty in the US disproportionately affect impoverished and under-represented minority populations. The major neglected infections include the helminth infections, toxocariasis, strongyloidiasis, ascariasis, and cysticercosis; the intestinal protozoan infection trichomoniasis; some zoonotic bacterial infections, including leptospirosis; the vector-borne infections Chagas disease, leishmaniasis, trench fever, and dengue fever; and the congenital infections cytomegalovirus (CMV), toxoplasmosis, and syphilis. These diseases occur predominantly in people of color living in the Mississippi Delta and elsewhere in the American South, in disadvantaged urban areas, and in the US–Mexico borderlands, as well as in certain immigrant populations and disadvantaged white populations living in Appalachia. Preliminary disease burden estimates of the neglected infections of poverty indicate that tens of thousands, or in some cases, hundreds of thousands of poor Americans harbor these chronic infections, which represent some of the greatest health disparities in the United States. Specific policy recommendations include active surveillance (including newborn screening) to ascertain accurate population-based estimates of disease burden; epidemiological studies to determine the extent of autochthonous transmission of Chagas disease and other infections; mass or targeted treatments; vector control; and research and development for new control tools including improved diagnostics and accelerated development of a vaccine to prevent congenital CMV infection and congenital toxoplasmosis.

Diseases caused by worms and parasites are draining the health and energy of the poorest Americans, an expert said on Tuesday. And diseases associated with the developing world, such as dengue fever and Chagas disease, may become a bigger problem for the United States as the climate changes, said Dr. Peter Hotez of George Washington University and the Sabin Vaccine Institute in Washington. "The message is a little tough because they are not killer diseases -- they impact on child development, intellectual development, hearing and sometimes even heart disease," Hotez said in a telephone interview. He said the diseases help to keep people mired in poverty, as infections may last years, decades or even lifetimes.