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Biomedical subjects

S C Hadler

Publications and source records attributed to S C Hadler.

At least 91 records · Page 5Linked to original sources

Postmarketing surveillance for neurologic adverse events reported after hepatitis B vaccination. Experience of the first three years.

In 1982, the Centers for Disease Control, the Food and Drug Administration, and the manufacturer created a surveillance system to monitor spontaneous reports of adverse events occurring after inoculation with the new plasma-derived hepatitis B vaccine (Heptavax-B, Merck Sharp and Dohme, West Point, PA). In the three years between June 1, 1982 and May 31, 1985, an estimated 850,000 persons received the vaccine. During that period, a total of 41 reports were received for one of the following neurologic adverse events: convulsions (five cases), Bell's palsy (10 cases), Guillain-Barré syndrome (nine cases), lumbar radiculopathy (five cases), brachial plexus neuropathy (three cases), optic neuritis (five cases), and transverse myelitis (four cases). Half of these occurred after the first of three required vaccine doses. There were no deaths. Calculation of the relative risks of these illnesses after hepatitis B vaccination was highly dependent on diagnostic classification of the cases, estimates of the size of the vaccinated population, background incidence of the diseases, and the length and distribution of the hypothetical at-risk interval used in the analysis. Other factors important in judging the results of the study could not be measured, including underreporting. In some analyses, Guillain-Barré syndrome was reported significantly more often than expected (p less than 0.05, Poisson probability distribution). However, no conclusive epidemiologic association could be made between any neurologic adverse event and the vaccine. Even if such an association did exist, the preventive benefits of the vaccine in persons at high risk for hepatitis B would unequivocally outweigh the risk of any neurologic adverse event.

Evaluation Studies as Topic↗

Outbreak of severe hepatitis due to delta and hepatitis B viruses in parenteral drug abusers and their contacts.

We investigated an unusually large and severe outbreak of hepatitis B, primarily involving parenteral drug abusers and their sexual contacts, in Worcester, Massachusetts, over a 21-month period from 1983 to 1985. Of 135 patients with drug-related acute hepatitis B, 81 percent were parenteral drug abusers and 19 percent had sexual contact with drug abusers; 13 fulminant cases resulted in 11 deaths. Among the patients with hepatitis B, evidence of delta virus infection was found in 54 percent of drug abusers, 33 percent of their sexual contacts, and 9 percent of other patients with acute hepatitis B (P less than 0.001). Most of the delta infections (86 percent) were coinfections with hepatitis B virus; the balance were superinfections. Delta infection was strongly associated with fulminant hepatitis: 91 percent of patients with a fulminant outcome had delta infection, as compared with 45 percent of less severely ill drug abusers and their contacts (P = 0.0037). Alcohol, other drugs, and other hepatitis viruses could not be implicated as hepatotoxic cofactors for fulminant disease. This outbreak appeared to result from the concurrent spread of hepatitis B and delta viruses among new drug users. Control measures included the distribution to physicians of guidelines on prophylaxis in contacts of patients with hepatitis B, health education for drug abusers, and a hepatitis B vaccination program. Despite these efforts, the outbreak continued unabated until the number of new cases began to decline slowly in late 1986.

Acute Disease↗

The effect of underreporting on the apparent incidence and epidemiology of acute viral hepatitis.

To determine if passively reported cases of acute viral hepatitis are representative of the affected population, an active surveillance system was set up that identified all persons in Pierce County, Washington, who had been diagnosed by a physician as having acute viral hepatitis in the period March 1 through August 31, 1984. In this county, this was part of an ongoing epidemiologic study of viral hepatitis that had previously included some stimulation of reporting. The active surveillance system covered all primary sources of medical care, including all private physicians who were most likely to see persons with hepatitis. Secondary sources, those that did not provide direct medical care but might be aware of new cases, were also surveyed. The results of active surveillance showed that passive reporting was about 65% complete in Pierce County. No change occurred in the number of hepatitis A cases reported, but hepatitis B cases increased by 50%, and non-A, non-B hepatitis cases increased by 138%. Most of the increase was a result of enhanced reporting from private physicians. The two risk groups most affected by underreporting were homosexual men with hepatitis B and blood transfusion recipients with non-A, non-B hepatitis. During active surveillance, the proportion of persons with hepatitis B who reported homosexual activity was 52% compared with 20% from passive surveillance. Transfusion recipients represented 24% of the non-A, non-B hepatitis reported from active surveillance compared with 9% reported from passive surveillance. Although Pierce County may not be representative of all counties in the United States, persons responsible for public health prevention programs should recognize that data acquired through passive surveillance may not accurately reflect the magnitude of the risk for specific populations or the amount of disease that can be prevented.

Adult↗

Long-term immunogenicity and efficacy of hepatitis B vaccine in homosexual men.

To study the duration of antibody persistence and protection provided by the hepatitis B vaccine, we followed 773 homosexual men for five years after completion of vaccination. Among the 635 participants in whom antibody levels above 9.9 sample ratio units (SRU) developed after vaccination, 15 percent lost antibody altogether, and in another 27 percent, antibody levels declined below 10 SRU within five years. The extent of the maximal antibody response strongly predicted the persistence of protective antibody. Hepatitis B infection occurred in 55 men; 8 of these infections were clinically important (characterized by the presence of the hepatitis B surface antigen and elevation of liver-enzyme levels), and two of the patients became hepatitis B virus carriers. The long-term risk of hepatitis B infection was inversely related to the maximal antibody response to vaccine. Most severe infections occurred among those who responded poorly or had no response to the vaccination. The risk of late infection with hepatitis B in those with an initially adequate vaccine response increased markedly when antibody levels decreased below 10 SRU, but only 1 of 34 late infections resulted in viremia and liver inflammation. A second series of vaccinations induced a moderate antibody response in 50 percent of the subjects who initially had no response or a poor response; however, the persistence of antibody was poor. Both antibody loss and the risk of severe disease should be considered when booster-dose strategies for the hepatitis B vaccine are being designed.

Carrier State↗

Lethal outbreak of hepatitis B in a dental practice.

Between April 1, 1984, and Feb 1, 1985, nine cases of hepatitis B occurred in the patients of a dentist practicing in a rural Indiana county (population, 35,000). This was over 20 times the mean annual incidence for the county in the previous decade. All of the patients had been treated by the dentist two to five months before illness. Although the dentist had never had hepatitis symptoms, his serum was positive for hepatitis B surface antigen and hepatitis B e antigen and negative for anti-hepatitis B core IgM antibody, indicating that he was probably a hepatitis B carrier. Two patients (22%) died of fulminant hepatitis; the case-fatality ratio was over ten times the reported US mean for hepatitis B. Using a case definition based on anti-hepatitis B core IgM antibody positivity and exposure to the dentist during a defined time period, a serosurvey of the dentist's patients identified 15 asymptomatic cases (overall attack rate, 3.2%). Infection risk was related to the amount of trauma involved in the cases' dental procedures. No cause was found for the unusual lethality of the outbreak.

Adult↗

Transmission of hepatitis B with resultant restriction of surgical practice.

Five patients developed acute hepatitis B (HB) within four months after major operations by the same obstetric-gynecologic surgeon. Investigation documented that the surgeon was HB surface antigen and HB e antigen positive; all five patients had an HB subtype matching that of the surgeon and no other identifiable risk factors for HB viral infection. A seroprevalence study comparing exposed surgical and obstetric patients with a control group showed no significant additional subclinical HB transmission. The surgeon resumed his surgical practice but was required to obtain written informed consent from patients, to double-glove, and to employ appropriate surgical techniques to avoid self-injury. Seven months later, acute HB occurred in a patient two months after a cesarean section, resulting in exclusion of the surgeon from major operations. This is the fifth outbreak of nosocomial HB linked to an obstetric-gynecologic surgeon, and it reinforces the need for health care workers to receive preexposure prophylaxis with HB vaccine to prevent such occurrences.

Carrier State↗

A Community-wide epidemic of hepatitis A in Ohio.

Between June 1, 1983 and August 30, 1984, an epidemic involving 313 cases of hepatitis A occurred in Muskingum County, Ohio. One hundred ninety-seven cases occurred in the city of Zanesville, with 34.7% of cases concentrated in two neighborhoods in the eastern part of the city. Case characteristics were similar to those reported in previous community-wide outbreaks, including a maximum attack rate among 5-9-year-olds and a very low attack rate in adults over 30 years. Case households were larger, and their members were less educated than the mean for households in the city. Forty-eight per cent of the cases reported exposures to other cases which temporally could have been the source of infection. A case-control study failed to show differences in several behavioral factors between case and control households, but did confirm that lower socioeconomic status was a risk factor for the disease. Broad use of immunoglobulin was effective in preventing clinical disease among family contacts, but did not stop the outbreak. This outbreak typifies a genre of hepatitis A epidemic transmitted from person to person in which exact routes of spread are poorly understood and control is difficult. Lower socioeconomic status may be a marker for some unidentified behaviors that promote hepatitis A transmission.

Adolescent↗

Nosocomial transmission of delta hepatitis.

A previously asymptomatic carrier of hepatitis B virus receiving chronic hemodialysis developed acute delta hepatitis. The patient regularly received dialysis treatments on the same machine as a parenteral drug abuser with hepatitis B surface antigen (HBsAg)-positive chronic hepatitis whose serum was strongly positive for delta antibody. The drug abuser had a major bleeding episode that caused extensive environmental contamination 3 months before onset of illness in the index patient. No other patients receiving dialysis or staff members had evidence of delta infection. A surgeon previously infected with hepatitis B from the same parenteral drug abuser also had delta antibody. Testing for delta virus is indicated for both HBsAg-positive parenteral drug abusers and patients with hemophilia receiving chronic hemodialysis. All patients who are HBsAg- and delta-positive should receive dialysis separately from patients who are HBsAg-positive and delta-negative. Susceptible patients on dialysis and staff should receive hepatitis B vaccine to protect against both hepatitis B and delta virus infection.

Adult↗

Serologic markers for hepatitis B among Marshallese accidentally exposed to fallout radiation in 1954.

At least one serologic marker of prior hepatitis B infection (hepatitis B surface antigen, antibody to surface antigen, or antibody to core antigen) was found in 91.7% of 314 Marshallese tested. The prevalence of hepatitis B surface antigenemia (3.3%) in a subpopulation that had resided on Rongelap Atoll at the time of accidental exposure to radioactive fallout from a thermonuclear test in 1954 did not differ significantly from the prevalence in a selected unexposed population (10.5%).

Adolescent↗

Occupational risk of hepatitis B infection in hospital workers.

To estimate the risk of hepatitis B virus (HBV) infection among hospital workers, we measured the prevalence of HBV infection in employees in five hospitals in different parts of the country and examined the effect of occupational and non-occupational factors on HBV prevalence. Among 5,697 persons studied, serologic markers of HBV infection were found in 807 (14%). Prevalence of infection was strongly related to race (Asian greater than Black greater than White), sex (male greater than female) and increasing age. Risk related to health occupation, studied by examining the change in HBV prevalence with duration in occupational group, was most strongly correlated with frequency of contact with blood during work. Workers having frequent blood contact had the highest estimated infection rate (1.05 per 100 person-years) and those with moderate contact an intermediate infection rate, compared to a negligible infection rate in workers with no blood contact. Frequency of needle accidents had an independent, positive effect on HBV infection rates, while degree of patient contact had no effect. Infection risk was uniform among all hospitals for groups with frequent blood contact. Among different occupation groups, risk of HBV infection also correlated closely with degree of blood-needle contact during daily work. This study provides a general approach to assessing risk of HBV infection in hospital personnel, and indicates that risk may be most easily estimated by quantitating degree of blood-needle contact during daily work.

Adolescent↗

Incidence of hepatitis B in the penitentiary of New Mexico.

A study was conducted to determine the incidence of hepatitis B (HB) in a prison population. Forty-seven per cent of 455 male prisoners had evidence of past HB infection. HB seropositivity was most strongly correlated with: 1) a history of IV drug abuse; 2) age; 3) total time in any prison; and 4) race. During a one-year study period there were no clinical cases of HB in the prison and the seroconversion rate was 0.8 per cent among prisoners still incarcerated.

Adolescent↗