Discussion and summaryThe information presented shows that the HA test can be utilized for determining adenovirus antibody response. The test may be carried out with heated adenovirus antigen and yields results which relate to a current adenovirus infection. Hemagglutination antibody titrations can be performed at room temperature and readings may be made up to 18 hours after the initial 2 hour incubation without change in titration end-points. Although the HA test does not achieve type specificity, this test appears to be more specific than the CF test. Huebner et al. (17) have reported 74%–90% heterotypic crossing in the CF test. The HA test reported here deals only with types 4 and 7 adenovirus infections and by extending these studies to include other adenovirus type infections it may be possible to utilize this test more specifically to determine infections to other types.Based on preliminary data the HA test appears to be superior to the CF test in regard to determining infections in persons having ...