Nobody has managed to fully explain the reason why most human beings react to the sight of a lowly cockroach with feelings of disgust and repugnance.
Now, reports Weekly Playboy (July 14), there's a good reason to do so. People who come down with what they mistakenly believe to be just a case of the summer sniffles may start to wonder why their rasping cough, congestion and other respiratory symptoms persist even weeks later.
"It's called 'cockroach asthma' and it can be contracted by ingestion of cockroach droppings, body excretions or fragments from their dead exoskeletons," says Dr Yoshio Otani, operator of a clinic in Tokyo's Ikebukuro district.
It is already known that similar asthmatic conditions are caused by house mites and dust. But scientists in the U.S. have also realized that house dust can contain cockroach allergens that can lead to asthma. According to Otani, allergy specialists in Japan are increasingly turning their attention to cockroaches as a contributing factor.
"There's a report of three members of family -- a 41-year-old mother, 11-year-old daughter and 10-year-old son -- who all came down with cockroach asthma," he says. "Initial tests showed no reactions for house mites or dust, and their physician was confounded as to what was causing it -- until a blood test showed all three gave positive reactions to cockroach allergy.
"An inspection of their home showed that 'gokiburi' were running rampant. After a visit by an exterminator, they moved back in and have been free of the asthma since then."
Inhabitants of some foreign countries showed a high percentage of positive responses to the so-called "sensitization rate" for cockroaches: Taiwan topped the list with 54.9%; the U.S. state of Kentucky rated 36.9%; and India, 35%.
Allowing for differences in geographic distribution, Otani explains that four species of "gokiburi" are most likely to be found in Japanese homes: the "kuro gokiburi" (scientific name, Periplaneta fuliginosa Serville); "yamato gokiburi" (Periplaneta japonica); "wamon gokiburi" (Periplaneta americana) and "chabane gokiburi" (Blattella germanica).
Of the above, only the "yamato gokiburi" is indigenous to Japan, the others being "gairaishu" (invasive foreign species).
Otani continues. "These varieties tend to congregate in dark, warm and moist areas, such as under the kitchen or bathroom sinks. Their activity is nocturnal."
"Goki" have inhabited the Earth for some 300 million years, plenty of time to earn their well-deserved reputation for being amazing survivors. In addition to consuming the same foods that humans eat, they can feed on things like wallpaper or the adhesive used to bind books. A single human hair can provide a cockroach with sustenance for a week.
They're also damn fast. Try to imagine a "goki" the size of an automobile. (On second thought, maybe you shouldn't.) At that scale, its running speed would reach 220 kilometers per hour. "Even if it were to lose one of its legs, the other ones would balance out, and its running speed would not be affected," notes Otani.
Chasing down a "goki" and whacking it with a rolled-up magazine demands speed and dexterity; but exterminating the ones lurking in dark crevices requires a different strategy. Otani recommends the various commercial fumigants that react with water and transform the rooms of the house into a gas chamber. (It is necessary to leave the premises for several hours until the smoke dissipates.)
"Use them in every room," the doctor advises Weekly Playboy's readers. "Then repeat the process two or three weeks later, to make sure you kill the newborn bugs (from mama "gokis'" nearly indestructible egg cases) that had hatched since the first fumigation."© Japan Today