THE PEDIATRIC RESIDENT SUSCEPTIBLE TO VARICELLA: PROVIDING IMMUNITY THROUGH POSTEXPOSURE PROPHYLAXIS WITH ORAL ACYCLOVIR

Pediatric house officers or primary care physicians who have never had chickenpox present major problems for their patients and themselves. Inadvertent varicella exposure is likely to occur at least several times a year, with each exposure resulting in the administration of varicella-zoster immunoglobulin and loss of anywhere from 14 to 28 days of clinical training. The options available for physicians susceptible to varicella are: Avoid patients with varicella-zoster infections, and receive varicella-zoster immunoglobulin within 48 hours of exposure if inadvertently exposed. Physicians in this situation are at risk of exposing their patients to varicella and therefore must avoid patient contact from days 10 to 21 after exposure (Days 10 to 28 if given varicella-zoster immunoglobulin). Unless the physician develops varicella this scenario might be repeated as long as the physician is involved in primary care. Physicians can intentionally expose themselves to a patient with varicella. Once they resolve their chickenpox, they will have natural lifelong immunity to varicella. Unfortunately primary varicella infections in adults are associated with a much higher incidence of serious complications than those in children. Oral acyclovir given to adolescents at the onset of varicella has been shown to shorten the clinical course and severity of chickenpox, although its use in preventing serious complications is unproved. The use of oral acyclovir in adults to modify primary varicella has not been studied but might be expected to have a similar benefit. Varicella vaccine is another potential course of action for the varicella-seronegative physician. In one study 94% of healthy adults given two doses of varicella vaccine seroconverted. Only 56%, however, showed clinical protection after household exposure, although all cases were mild and no secondary transmission of vaccine virus occurred. Nevertheless secondary spread of varicella to contacts has been reported to occur in immunized adults and the long term protection in immunized adults is also unknown. Varicella vaccine, however, is not approved for use in the United States at this time. Until recently these three options were the only available courses of action. A recent study by Asano et al., however, suggested another possible option: postexposure prophylaxis with oral acyclovir. In that study 25 children received oral acyclovir for 7 days beginning 7 to 9 days after initial exposure to a household contact w