Roach trouble

Roach trouble there is more to the humble cockroach than meets the eye. Recently published research shows that its faeces, saliva, and other parts of the body act as an allergen. This leads to asthma among children, and exacerbates the more serious cases. A study of hundreds of severely asthmatic children aged between four and nine years from eight densely populated urban centres in the us reports that those allergic to cockroaches and heavily exposed to the insects at home were thrice as likely to be hospitalised than other asthmatic children ( New England Journal of Medicine , Vol 336, No 19).

Researchers already know that many asthmatics in inner cities are allergic to cockroaches. But the study is the first to systematically show that an allergic person exposed to high levels of cockroach allergen has a remarkably higher risk of suffering major asthmatic attacks.

The five-year study was conducted in eight medical centres in seven cities by a team led by David L Rosenstreich of the Albert Einstein College of Medicine, Bronx, New York. The researchers wanted to find out why asthma related problems were severe among children from inner-city areas who were allergic to a specific allergen found in bedroom dust. They traced high levels of cockroach allergen in the dust of the bed rooms of more than half of these children.

The study revealed that children exposed to cockroach allergen wheezed a lot more, slept little during nights, and missed school more often than unexposed asthmatic children. They were 80 per cent more likely to make unscheduled medical visits for asthma. Such patterns were not found for other allergens from dust mites and cat dander, among others.

Asthma is a debilitating respiratory condition that strikes one in every 10 children in the us . The problem appears to be far more serious in some Indian cities. A study from Bangalore revealed that instances of asthma in children have risen from 9 per cent in 1979, to 24.5 per cent in 1994. This means that every fourth child is an asthmatic. Physicians estimate that about 10 per cent adults in the city have asthma. The count is rising constantly due to increasing pollution levels in the metros.

Most instances of asthma result from viral infections, tobacco smoke, allergic reaction to mould, animal dander, dust mites, pollen or other allergens. A recent study has identified as many as 250 items, handled daily by different categories of workers at work premises, that trigger off cause asthma in those allergic to them.

While the causes of asthma are not clear yet, the mechanics of the ailment are fairly well known. Asthma, meaning