Effects of cockroach salivary secretions and serum on human blood cells.

Salivary fluids of Blaberus craniifer, a common pest species of cockroach, were found to produce leukocytolysis and hemagglutination reactions of human blood cells under in vitro conditions. Blood sera from these insects produced similar reactions, as well as the capacity to lyse human erythrocytes. The cockroach is known to regurgitate while feeding. These findings suggest the potential of the insect to induce adverse effects on human blood cells as a consequence of persons being bitten or having lesions that serve as skin sites for cockroach feeding.