A potentially life-threatening parasitic disease long associated with Latin America is also present in the United States, researchers warn.
Chagas disease, spread by blood-sucking insects known as "kissing bugs", can cause devastating heart problems in humans and dogs.
Often called a “silent” infection, Chagas can go unnoticed for years because most people experience few or no symptoms initially. Yet the World Health Organization estimates it kills around 10,000 people annually and puts up to 75 million worldwide at risk.
While it can cause acute symptoms like swelling in the limbs or eyes and even anaphylaxis, its long-term effects, of heart attacks or strokes, pose the greatest danger.
How does the disease spread?
Kissing bugs, which feed on blood like mosquitoes and ticks, are central to the transmission of Chagas.
"This is not a disease that's regularly transmitted from human to human directly, or even from animal to human directly,” explained Dr. Sarah Hamer, a veterinary epidemiologist at Texas A&M University.
"That's why the kissing bug, in that insect vector, is so critically important to the transmission of this disease".
Humans usually become infected when a kissing bug defecates while feeding, allowing the parasite in its faeces to enter the body.
Dogs, by contrast, can contract the parasite by eating the insects.
A difficult disease to detect
The parasite often goes undetected, silently damaging the body over the years.
"This can cause a pretty devastating heart disease when the parasite enters the heart tissue and alters the ability of the heart to function like it normally would," says Hamer.
Yet awareness and testing remain limited.
"There's not a lot of awareness in the human medical community or the veterinary medical community that this really is a disease that can be locally transmitted here in the United States,” Hamer stressed.
While Chagas is endemic in the US, experts stress that the risk of locally acquired infections appears lower than in Latin America, partly because the kissing bugs in the US tend to remain outdoors rather than inside homes.
