The most significant problem is that cockroach allergen appears to be a very troublesome trigger for asthma in children particularly, but not only, inner city children. Studies show that 78 percent to 98 percent of urban homes have cockroaches. If you see one, it's safe to assume that there are at least 800 hidden. That is a scary statistic.
Commercial traps can be helpful but occasionally professional extermination in necessary.
Proper precautions should be undertaken to be sure the allergic person is not exposed to extermination fumes. Be sure pyrethrum is not used by the exterminator. The house should be well-aired out before the person returns, using either the passive or active method. Following the eradication, your house should be vacuumed at least once a week. And pay particular attention to cleaning bathrooms and kitchens where cockroaches find sources of food or water.