Effect of multiple use of dialyzers on hepatitis B incidence in patients and staff.

Data pertaining to incidence of hepatitis B from a 1976 Center for Disease Control Study were matched with responses from a Renal Physicians Association survey on dialyzer reuse in the United States. Of 6,079 patients, 166 (2.7%) became positive for hepatitis B surface antigen (HBsAg) in 96 centers practicing reuse, whereas 495 (2.6%) of 18,947 became HBsAg positive in 439 centers practicing single use. Among staff, 75 (2.5%) of 3,049 became positive for HBsAg in centers practicing reuse vs 200 (2.3%) of 8,696 in centers not reusing dialyzers. Incidence of infection among staff associated with a center having at least one HBsAg-positive patient was 2.9% in centers practicing reuse vs 3.6% in centers practicing single use. Nearly all (95%) staff who became HBsAg positive were associated with centers having at least one HBsAg-positive patient. The practice of reusing dialyzers does not appear to be associated with increased risk of hepatitis B infection among patients and staff.

Guidelines for the care of patients hospitalized with viral hepatitis.

For years patients hospitalized with viral hepatitis have been placed in two categories of isolation--enteric precautions and blood precautions. This strategy was based on the inability to differentiate between hepatitis A and B and on the assumption that feces and blood from patients with either type might be infective. It is now known that patients with hepatitis A do not pose a problem of disease transmission through direct contact with blood, and although blood of patients with hepatitis B may be infective, the virus is not transmitted via feces. The enteric route is the principal mode of transmission for hepatitis A, but maximal levels of hepatitis A virus excretion occur before the onset of jaundice. Non-A, non-B hepatitis is similar epidemiologically to hepatitis B. Thus, the major thrust for caring for patients hospitalized with viral hepatitis is toward blood precautions; the same precautions used when handling feces, urine, and excretions from all other hospitalized patients are appropriate for patients admitted with a diagnosis of hepatitis A.

A nationwide survey of heavy metal absorption in children living near primary copper, lead, and zinc smelters.

Arsenic, lead, and cadmium absorption levels were determined in 1774 children 1-5 years old living in 19 USA towns with primary nonferrous metal smelters. Results were compared with data on 258 children of the same age in three communities without smelters. Increased systemic absorption of arsenic, as reflected by urine arsenic content, was noted in children near 10 of 11 copper smelters. Blood lead levels were also modestly elevated near two copper smelters. Near lead and zinc smelters, elevated levels of lead and cadmium in hair provided evidence of external exposure to these elements. Levels of lead in blood were not, however, elevated near any of three lead smelters and were elevated near only two of five zinc smelters. Blood cadmium levels were high near one lead and two zinc smelters. The apparent sources of exposure (except in one community with elevated levels of arsenic in drinking water) were air, soil, and dust contaminated by smelting operations. While the full biologic significance of these findings is not known exposure of children to toxic heavy metals emitted by smelters should be reduced to a minimum.

An outbreak of type B hepatitis associated with transfusion of plasma protein fraction.

An outbreak of type B hepatitis followed transfusion with a single lot of plasma protein fraction (PPF) at a 1200-bed hospital in June and July 1973. Of 51 recipients of the product, 31 were available as a study population and 19 (61%) had an illness compatible with hepatitis. Epidemiologic and serologic investigations provided firm evidence that this material was the vehicle for transmission of disease to its recipients. Recipients of four other PPF lots from the same manufacturer were studied. Two of these lots were also associated with extremely high clinical hepatitis attack rates (45% and 55%). The other two lots, which had been prepared from donor plasma contributing to the composition of the initially-studied PPF lot, failed to produced clinical illness, although one of these lots was associated with a high prevalence of hepatitis B seropositivity in recipients. Thus, a broad spectrum of clinical and serologic responses was evident in PPF produced from similar donor plasma and pasteurized in the same bulk container. This study is the first to incriminate heat-treated PPF in transmission of type B hepatitis and suggests the need for further studies of the effect of pasteurization cycles on inactivation of hepatitis B virus.

Hepatitis A: report of a common-source outbreak with recovery of a possible etiologic agent. I. Epidemiologic studies.

From the end of October to the end of December 1973, an epidemic of hepatitis A affected 40 students at a state university, 11 employees of two restaurants, and 11 other residents in a southwestern metropolitan community. Two distinct epidemic waves of illness occurred, and investigation implicated two local restaurants as sources of infection, one for each epidemic wave. An index patient who prepared food was identified at each restaurant, and the two restaurants were linked by the fact that the index patient who worked at the second restaurant had patronized the first restaurant. Foods implicated as vehicles of transmission included 'guacamole,' green salad, spaghetti, and hamburger. The findings represent a rare example of a 'double' common-source outbreak with two distinct epidemic waves related to two separate eating establishments.