Occupational exponsure to HIV in an urban university hospital setting

In response to the potential transmission of the human immunodeficiency virus in a hospital setting, an occupational exponsure assessment program was established at a New York City university hospital in 1990. During the first year, 322 potential exposures to blood or body secretions in 313 health care workers (HCWs)were reported. Exposures occurred most frequently on the surgical service (36 percent), and in patients' rooms (37 percent). Nurses accounted for 53 percent and physicians 25 percent of reported exposures. A percutaneous injury was reported by 78 percent of HCWs. Human error was responsible for the exposure in 54 percent of HCWs and was associated with a break in universal precautions in one-third. The immune status for HIV antibody, hepatitis B antigen and hepatitis C antibody was positive in 11 percent, 3 percent and 9 percent in source patients, respectively. However, the immune status for these potential nosocomially transmited pathogens was not determined in 12 percent and 26 percent of source patients. Based on the source patients HIV antibody status and the extent of injury, zidovudine was recommended to 39 HCWs; 12 refused prophylaxis. HIV seroconversion was not documented in those HCW who returned for follow-up testing. A similar assessment program for medical students rotating on the surgical service revealed that two-thirds were exposed to blood or body fluids while in the operating room. Only 16 percent of sharps injuries were self-inflicted, whereas 66 percent were caused by another HCWs, usally a surgical attending or houseofficer. These data underscore the necessity for institutional programs regarding management of HCWs potentially exposed to HIV. Such programs not only provide an indispensable service to the exposed HCW and medical student, but also a means by which infection control policies and educational programs may be monitored and implemented.

Emerging pathogens associated with tick-borne infections

In recent years, several microbial agents have been identified that result in significant morbidity and mortality. The newly recongnized tick borne infections, babesiosis and ehrlichiosis, may be transmitted by the same tick that transmits Borrelia burgdorferi and simultaneous infections may occur. Babesia are intraerythrocytic protozoa that may cause severe hemolytic anemia, whereas Ehrlichia, depending on the species, may infect either monocytes or granulocytes, with associated leukopenia, thrombocytopenia and anemia. Improved laboratory surveillance is urgently needed to assess the prevalence of these worldwide pathogens in order to institute appropriate infection control efforts.