Medical School Expedition to Guatemala Evolves Cure For Tropical Disease--Source of Infection is Traced to Flies

A system of treatment has been evolved by members of the Department of Tropical Medicine which it is believed can entirely eradicate Onchoceren, a serious parasitical infection now prevalent among workers on Guatemala coffee plantations, in the course of five or six years of a properly conducted campaign it was announced recently at the University Medical School.

Dr. R. P. Strong, who conducted a survey of the Republic of Liberia two years ago where he observed a similar disease, was selected to head the Guatemala expedition with the backing of the Department of Tropical Medicine and the medical department of the United Fruit Company. It was discovered that infection was transmitted by several varieties of coffee flies that were carriers of the adult Onchecereae, present in the tuners found on the heads of the natives. Once injected by the bite of the fly, the parasites multiply and the young "microfilariae" circulate through the lymphatics, causing irritation, particularly of the eye. Any fly biting an infected person is at once a potential source of infection. The investigators discovered, however, that these Eusilium flies are so widely distributed in practically every running stream of water in the endemic districts that their eradication is practically impossible. Actual cure must come as a result of individual treatments and isolation of all infected persons.

It was at first suspected that mosquitoes might be carriers, as in the case with malaria. Numerous microscopic examinations, however, revealed that either because its sting is administered more deeply in the flesh or because the saliva of the insect is inimical to the parasite, the mosquito is definitely not a carrier. That the Eusimulium fly was the true source of infection was proved conclusively by over 2000 microscopic examinations.

During the expedition, 261 operations were performed. Any treatment to be of permanent value must include blood tests for traces of the microfilariae which persist after the tumors have been removed. Patients may still carry dangerous infection until these parasites are completely discharge from the system. Efforts were directed more toward public than individual health.

The government of Guatemala is at present too poor to finance an effective program for eliminating the disease. The most probable source of aid would seem to lie in some American foundation which could endow a thorough campaign of operation and isolation which alone can effect solution of the problem.

Generally speaking members of the expedition believe that the tropics can never be made more than comparatively liveable for the white man and see no prospect of his becoming adapted to life in the hot regions. The expedition's report in regard to Onchocerciasis written at Moca, Guatemala, states that "Public health procedure should include inspection of the inhabitants in the endemic districts and the diagnosis of the cases with filarial tumors with prompt removal of the fibroid growths. The operations are simple and easily performed under local novocaine anesthesia. In case of an individual refusing to be operated upon, he should be isolated and not allowed to reside in a region where the Eusimulium concerned in the transmission prevail. Since the microfilariae do not disappear immediately following the operation, but often persist for a considerable time thereafter, (and in cases with no further detectable tumors,) periodic microscopical examinations should be made after operation to detect the number of microfilariae which persist.

If large numbers of microfilariae art still present, the individual should be regarded as a dangerous carrier and isolated until the parasites diminish or disappear".

Dr. Strong will return to Guatemals in the course of a month to join Dr. G. C. Shattuck '01 and Dr. J. L. Bremer '96 who are now conducting an investigation for the Carnegie Institute as to why the ancient Maya tribe is at present dying out.

Members of the Onchocerca expedition included Dr. J. C. Bequart, assistant professor of Entomology at the Department of Tropical Medicine, Dr. M. M. Ochea chief of the parasitological division of the Department of public health of Guatemala and B. Rennett, a technician of the department of Tropical Medicine