Dipstick tests for three neglected diseases
Clinical trials of a quick, cheap test for three neglected diseases are likely to begin in five years, researchers have confirmed.
The three-in-one 'dipstick' test would provide a reliable diagnosis of Chagas disease, leishmaniasis and African trypanosomiasis (sleeping sickness) within one hour at a cost of a few US cents per sample. It is being developed in California, United States.
The WHO estimates that some three million people, most of them in the developing world, will get infected with one of the three diseases this year.
A dipstick test could deliver results even in remote areas that lack microscopes and trained health workers. There are currently only a few accurate and affordable ways of diagnosing these diseases and, as a result, many cases are missed.
In the new test, a dyed strip is dipped into a blood sample from a potential patient. The test picks up a signature "biomarker" molecule from a parasite, which causes the colour of the dipstick to change under ultra-violet light — indicating parasite presence. Since the diseases are caused by related parasites, a single test might suffice to detect them all — providing an efficient biomarker is found.
"...finding an ideal biomarker, which is easy to detect, sensitive and specific [an accurate indicator of the disease] is ... complicated," said Pere Simarro, the head of WHO's African trypanosomiasis programme.