Effect of silver nitrate application on the conjunctival flora of the newborn: and the occurrence of clostridial conjunctivitis.

Newborn conjunctival cultures were obtained from 35 babies prior to silver nitrate application and 48 hours later. On initial culture, 46 facultative bacteria and 27 anaerobes were recovered; 48 facultative and 18 anaerobes were recovered after 48 hours. Haemophilus vaginalis, Bacteroides species and anaerobic cocci decreased in numbers, whereas S. epidermidis, Micrococcus and Propionibacterium acnes increased during this time interval. Clostridial species were isolated from two cases who developed conjunctivitis, along with Peptostreptococcus in one of the cases. In vitro experiments demonstrated lack of killing of C. perfringens in silver nitrate concentrations of 0.1 percent, even after 24 hours exposure.