Prevention of Virus Interference by 2,5-Dimethylbenzimidazole

Summary Interference among homologous and heterologous strains of influenza A and B viruses has been demonstrated in chorioallantoic membrane cultures in vitro. The preparation of inactivated influenza A or B viruses for interference experiments by heating at low temperatures (22° or 37°C) preserved more of the interfering activity of the untreated virus than heating at 56°C, although infectivity was effectively eliminated in all instances. 2,5-Dimethylbenzimidazole, at a concentration of 2.6 × 10-3 M, prevented, to a varying extent, the induction of interference by inactivated influenza A (WS strain) or influenza B (Lee strain). Holding membrane cultures at 4°C in the absence of the compound had a similar effect.