One Health Movement News / One Health Topics 'in' the News

"HONOLULU (HawaiiNewsNow) -

Scientists now know what caused the death of a Hawaiian monk seal found near the Ala Wai Boat Harbor last week: toxoplasma gondii, a parasite commonly associated with cats.

"It's something that is shed into the environment from cats and their feces," said Michelle Barbieri, of the National Oceanic and Atmospheric Administration Fisheries Division. "It's washed mauka to makai in the environment."

The parasite lives in the muscle tissue of its host animals, which are rodents and small birds. When consumed by cats, the parasite reproduces in the digestive tract and is released into the environment through the cat's defecation."

Excerpt: If Thomas Cropper, a public-health veterinarian at Lackland Air Force Base, in San Antonio, Texas, thought about Chagas disease at all, he thought about it as a Central and South American problem. Named after the Brazilian physician who described it, in 1909, Chagas is a classic—one might say egregious—example of a neglected tropical disease. It is caused by the protozoan parasite Trypanosoma cruzi, which is delivered to its host by kissing bugs, known formally as triatomines. The bugs are bloodsuckers—their nickname comes from their penchant for biting near the eyes or mouth—and they can swell to the size of grapes as they feed, causing them to defecate and leave the parasite behind to make its way into the host’s bloodstream. A gross and not particularly efficient mode of transmission, it’s still good enough to have kept Chagas going since pre-Columbian times. According to the World Health Organization’s shifting estimates, between six and seven million people in Latin America are currently infected. If you’re infected but don’t have symptoms, you’re likely to find out only after donating blood. If you do have symptoms, you’re probably in trouble. About a third of Chagas patients develop a chronic form that leads to heart damage and failure.

BACKGROUND: Despite ongoing advances in biomedicine, infectious diseases remain a major threat to human health, economic sustainability, and wildlife conservation. This is in part a result of the challenges of controlling widespread or persistent infections that involve multiple hosts, vectors, and parasite species. Moreover, many contemporary disease threats involve interactions that manifest across nested scales of biological organization, from disease progression at the within-host level to emergence and spread at the regional level. For many such infections, complete eradication is unlikely to be successful, but a broader understanding of the community in which host-parasite interactions are embedded will facilitate more effective management. Recent advances in community ecology, including findings from traits-based approaches and metacommunity theory, offer the tools and concepts to address the complexities arising from multispecies, multiscale disease threats.