Increase in cases of Hydatidosis causes concern

CHENNAI, JULY 12. The number of positive cases of Hydatidosis, a parasitic disease in human serum samples reported among city residents at the Madras Veterinary College has caused apprehension among the faculty.

The Department of Parasitology says the cases (caused by tapeworms in dogs) referred to it is more due to recent higher awareness of the parasitic infection among medical practitioners.

More than 10 samples sent by some of the Government hospitals and private medical practitioners last month have been tested positive. The disease should receive the same attention given to Leptospirosis or rather a little more, according to Director, Centre for Animal Health, Dr. G. Rajavelu.

Cystic hydatidosis is the name given to the infection of tape worms called ``echinococcus granulosus''. The infection is common in sheep-rearing areas and disease transmission occurs between dogs and cattle, man is considered an ``intermediate host'' and dogs the primary source of spread.

Lack of hygiene, improper sanitation facilities, uncontrolled stray dog population and slaughter of livestock in insanitary conditions lead to the spread of the eggs of the tape worms. In urban areas the infection is picked up by the humans from public places, slaughter houses and also due to close association with pets, living in unhygienic conditions. The microscopic eggs enter the human body through the oral route. Of over 100-odd human samples, received on a referral basis, screened by the department, during the past two years, 39 per cent were positive.

The number reported in animals were 262. The university researchers, who obtained a feedback on the infected victims say, the afflicted age group is between 20 to 50. However, some children between 5-14 years have also been diagnosed positive.

More than the number diagnosed is the number that go undetected, says Assistant professor of the Parasitology Department, Dr. M. Raman. In the initial stage of infection, which is always asymptomatic as the cysts for developing to a certain size require months and in some cases years for development to a particular size. Usually they do not induce clinical symptoms, before they reach a certain size depending on the organ of the human body where they lodge. One Government hospital in the city has reported treating over 2,500 cyst complaints last year, he says.

The authorities say very little data is available on the mortality rate and it depends on where the cysts forms. The Parasitology Department provides free diagnosis of serum. The counter immuno electro phoresis test is considered one of the best for detecting the anti-bodies and the laboratory requires no more than an hour to furnish results. The cysts could be located by other medical care equipment such as scans, ultra sound and endoscopy. Common treatment is by surgical intervention.