Battling Enemy #2

THERE ARE 38 Navymen at PMU Da Nang. In their personal war the Viet Cong are a nuisance and disease is the enemy. Their greatest worries are the mosquitoes. And the rats.

PMU stands for Preventive Medicine Unit. The Navymen combat cholera, typhus, plague, encephalities, dengue and malaria in the 66,000 square miles of the First Corps area between the 17th parallel and Quang Ngai.

One of the unit's five sections operates a laboratory at the Force Logistics Support Group in an area west of the Da Nang Air Base. The lab is equipped specifically to perform bacteriological tests.

When someone in the area is afflicted with an infectious disease, it is often this lab which makes the positive identification of the specific bacterium or parasite which is causing the illness. Early diagnosis is essential for proper treatment of the patient and, in certain situations, for prevention of spread of the disease.

The Medical Service Corps officer and his three enlisted assistants at the lab also examine biological specimens collected by other members of the PMU.

COLLECTORS - PMU men get insects from trap, dip mosquito larvae from stream and identify species of a mosquito.

THE UNIT also has an entomology section - a mobile bug group, to be nontechnical. An MSC officer and five enlisted men keep track of insects, especially mosquitoes.

When there is an outbreak of malaria, the entomology group is sent to the location where they collect mosquito specimens and decide which of the many varieties is the culprit.

Once the carriers are identified, chemicals are used to kill them. A survey of the mosquito population is made before spraying and is matched with a later one to determine the effectiveness of the spraying. The region is then watched carefully for any sign of return of the problem.

In the course of their work, the entomology group has classified more than 3600 insect species. Their collection of insects prevalent in Viet Nam is one of the world's most extensive.

When spraying the area to kill the mosquitoes is indicated, the assignment goes to Lieutenant Berlin Taylor, a former hospital corpsman who is now an MSC officer. He and his vector control team of a dozen men use a helicopter which has been modified for insecticide dispersal.

The airborne spraying apparatus is often used to clear areas of insect pests. Locations such as Camp Tien Sha, the main berthing cantonment for the Naval Support Activity, Da Nang, and other areas within the city are frequent targets for spraying. An overabundance of pesty insects, even though they do not carry disease, can have unsettling effects on morale.

CHEMICAL SPRAY is spread over jungle via helicopter to kill mosquito larvae.

ANOTHER SPECIALTY of the Preventive Medicine Unit is mammalogy A five-man team collects and identifies the various local species of mammals, and watches them carefully for indications of disease. This team has collected over 250 rats in 14 species alone, not to mention a long and varied list of snakes, squirrels and shrews.

The mammalogy group occasionally makes a spectacular find. Hospital Corpsman Third Class Thomas J. McIntyre and Hospital Corpsman First Class Paul F. Ryan recently returned to headquarters with a douclangur, a rare primate which, according to one source, has not been found in a zoo since 1880.

-Howard M. Geiger, YN1, USN 

Page 21