Testing dogs for tropical diseases in Panama: what works and what doesn't

In rural Panama, dogs act like living alarms for two dangerous diseases spread by bugs. One disease, called American cutaneous leishmaniasis, causes skin sores and is carried by sandflies. The other, Chagas disease, attacks the heart and is spread by kissing bugs. Both diseases are common in the same areas, making it tricky to tell which dogs are sick. Researchers tested 311 dogs from 12 villages in Coclé Province using different blood tests. For leishmaniasis, they tried two methods: ELISA, which looks for antibodies in the blood, and IFAT, which lights up certain cells under a microscope. For Chagas disease, they used four tests, including a quick paper-strip test similar to pregnancy tests. The goal was to find the most reliable and affordable way to check dogs for these diseases without a perfect gold standard test.The results showed ELISA was best for leishmaniasis, correctly identifying sick dogs 85% of the time and healthy dogs 87% of the time. For Chagas disease, pairing a costly lab test called MIA with the quick paper test gave the best results, both around 90% accurate. But since MIA isn’t available locally, scientists suggest using a different mix: a western blot test and the same quick paper test. This combo still catches most cases but costs less. One surprise was that some tests for leishmaniasis and Chagas disease gave mixed signals, possibly because the diseases are similar. This means doctors need to be careful when interpreting results. The study shows that in places where money and resources are tight, choosing the right tests matters just as much as how well they work.