I don’t know how many of you caught the recent run
of headlines reporting Chagas disease as the ‘new HIV/AIDS of the
Americas,’ but I was caught off guard.
These reports were based on an editorial written in
PLoS Neglected Tropical Diseases, which drew direct comparisons between
Chagas and the early years of the HIV/AIDS pandemic. I dissected the piece
carefully and was disappointed to find that there were no new data lending heft
to the bold proclamation. No new cluster of transmissions in the American
South, no blood bank mishap in the Midwest, no shadowy patient zero releasing
parasite laden kissing bugs on airlines destined to the US from South America.
So I did what I normally do when I am confused. I call
my expert friends, like Sue Montgomery of the CDC. It is true that there are a
lot of people who have Chagas disease in the Americas who don’t know it,
and about 300,000 of them reside in the United States. These are people who
immigrated from countries in Latin America where T. cruzi, the parasite
that causes Chagas disease, is transmitted by triatomine bugs. Most people
infected with T. cruzi do not develop symptomatic disease with cardiac
and gastrointestinal complications. But asymptomatic mothers with chronic
Chagas disease can transmit the infection to their children, and it is
estimated that up to 300 infants are born every year in the United States with
congenitally acquired Chagas disease.
Figure 1. Triatoma infestans or the “Kissing Bug”, “Assassin Bug”, or “Cone-Nose Bug”, is a vector for Chagas' Disease.
Asymptomatic patients with chronic Chagas disease can
also transmit T. cruzi via blood transfusion. But blood bank donor
screening has been in place in the United States since 2007 making our blood
supply safer. There are also species of triatomine bugs that are native to the
United States that can transmit infection, but this is a rare event —
since 1955 there have been only 23 cases identified this way.
But yes, Chagas is still very much a neglected disease
of poverty. And the burden of disease falls much off the shoulders of the poor
in rural Latin America where triatomine vectors are plentiful and individuals
are not commonly screened and treated. And while no one I know thinks it is the
new AIDS of the Americas — AIDS being too much of a metaphor of
devastation to really be a fair comparison — medical providers still need
to be better informed and educated to recognize and test patients appropriately
for Chagas. Political will needs to be there to fund new therapies, diagnostic
tests and health care delivery. If the intent of the editorial was to make me
sit up and pay attention, it did — but I am not sure it was the most