Childhood asthma is recently becoming a more serious problem, and much research has pointed to allergens from dust mites and cockroaches. The main cockroach allergens identified were from Blattella germanica whole body and fecal extracts. Since most cockroaches are parasitized by gregarines (Apicomplexa: Gregarinasina), it is possible that some gregarine allergens have been misidentified as cockroach antigens. Most notably, Gregarina blattarum spores may be causally related to human asthma in cities, where infestations of the host cockroach, B. germanica, are common, Fig. 1. Elimination or control of spores may be accomplished by killing the spores directly or indirectly by targeting the sporadin stage within the cockroach host. This parasite may also be a method of controlling populations of the cockroaches. Therefore, it may be useful to study the sporadin as well as the spore stages of the gregarine.