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K C Hyams

Publications and source records attributed to K C Hyams.

At least 19 recordsLinked to original sources
PubMed2001

Prevalence and incidence of hepatitis C virus infection in the US military: a seroepidemiologic survey of 21,000 troops.

Because of a high prevalence of hepatitis C virus (HCV) infection (10-20%) among veterans seeking care in Department of Veterans Affairs (VA) hospitals, current US military forces were evaluated for HCV infection. Banked serum samples were randomly selected from military personnel serving in 1997 and were tested for antibody to HCV (anti-HCV). Overall prevalence of anti-HCV among 10,000 active-duty personnel was 0.48% (5/1,000 troops); prevalence increased with age from 0.1% among military recruits and active-duty personnel aged <30 years to 3.0% among troops aged >/=40 years. Prevalence among 2,000 Reservists and active-duty troops was similar. Based on sequential serum samples from 7,368 active-duty personnel (34,020 person-years of observation), annual incidence of infection was 2/10,000. Of 81 HCV RNA-positive troops for whom genotype was determined, genotypes 1a (63%) and 1b (22%) predominated, as in the civilian population. These data indicate that HCV infection risk among current military forces is lower than in VA studies and the general civilian population aged <40 years. The low level of HCV infection may be attributed to infrequent injection drug use in the military due to mandatory testing for illicit drugs prior to induction and throughout military service.

Adolescent↗
PubMed2001

Endemic infectious diseases and biological warfare during the Gulf War: a decade of analysis and final concerns.

Infectious diseases were one of the first health threats confronted by Coalition troops deployed to the Arabian desert in August 1990. On the basis of experiences in World War II, the major endemic infectious disease risks were thought to be sandfly fever, cutaneous leishmaniasis, diarrheal disease, and malaria. Although there was active surveillance, no case of sandfly fever and few other endemic infectious diseases were identified among over 500,000 U.S., British, and Canadian ground troops. In addition, there was no diagnosis of biological warfare (BW) exposure, and BW agents were not detected in clinical, environmental, or veterinary samples. The most common infectious disease problems were those associated with crowding (acute upper respiratory infections) and reduced levels of sanitation (travelers-type diarrhea). Only one endemic infectious disease has been confirmed as causing chronic health problems: visceral Leishmania tropica infection (viscerotropic leishmaniasis). However, this protozoan infection was diagnosed in only 12 U.S. veterans, and no new cases have been identified during the last 8 years. Infectious diseases were not a serious problem for Gulf War troops because of extensive preventive medicine efforts and favorable weather and geographic factors. Moreover, it is unlikely that an endemic infectious disease or a BW agent could cause chronic health problems and remain undetected over a 10-year period.

Biological Warfare↗
PubMed2001

Serosurvey of Borrelia burgdorferi infection among U.S. military personnel: a low risk of infection.

A serosurvey of 9,673 United States military personnel was conducted to estimate infection rates with Borrelia burgdorferi sensu stricto, which is the cause of Lyme disease in the United States. Initial screening of sera from 9,673 military personnel on active duty in 1997 was performed by enzyme-linked immunosorbent assay (ELISA); supplemental testing of all ELISA-positive sera was performed by Western blot. Initial screening identified 1,594 (16.5%) ELISA-positive samples, but only 12 (0.12%, 95% confidence interval [CI] = 0.05-0.19%) were confirmed by Western blot. Antecedent serum samples collected from 1988 to 1996 were available for 7,368 (76%) subjects, accounting for 34,020 person-years of observation. Just two of the nine Western blot-positive individuals for whom antecedent samples were available seroconverted during military service for an annual incidence rate of six seroconversions per 100,000 persons (95% CI = 0.7-21.5). The risk of Lyme disease in the U.S. military population was found to be low. Although there may be sub-groups of military personnel who could potentially benefit from vaccination, force-wide use of the Lyme disease vaccine is not warranted.

Adolescent↗
PubMed2001

Viral hepatitis in the U.S. military: a study of hospitalization records from 1974 to 1999.

Viral hepatitis remains a health threat for military forces. Most recently, there has been concern about hepatitis C virus transmission during military service because a high prevalence of hepatitis C virus infection has been found in some U.S. veteran populations. In this study, hospitalizations of active duty U.S. military personnel for hepatitis were evaluated using standardized computer records. Only the first hospitalization was assessed during the period January 1, 1989, to December 31, 1999. Among active duty forces, the rate of hospitalization for all types of acute hepatitis declined from 13 to 1.1 per 100,000 personnel from 1989 to 1999. Males, nonwhite racial/ethnic groups, and older troops were more likely to be hospitalized for acute hepatitis. This study's finding of declining rates of acute hepatitis is a continuation of a trend observed since 1974. The decreasing risk of viral hepatitis in the U.S. military is attributable to several factors, including reduced levels of injection drug use because of routine, randomized drug testing.

Acute Disease↗
PubMed2000

Norwalk-like virus infection in military forces: epidemic potential, sporadic disease, and the future direction of prevention and control efforts.

The impact of Norwalk-like virus (NLV) infection on military forces is evaluated in this report. NLVs were a major cause of both outbreaks and sporadic disease among crowded US ground troops in the 1991 war with Iraq. NLVs also have been found to be a cause of acute gastroenteritis in other ground and shipboard deployments. Four large outbreaks of acute gastroenteritis were investigated aboard US Navy aircraft carriers between 1992 and 1997. In these outbreaks, NLVs were identified as the probable cause, and crowding was a major risk factor for transmission. An evaluation of a routine shipboard deployment also suggests that NLVs cause sporadic gastroenteritis. These data indicate that NLV infection is a major cause of acute morbidity in military forces. Because of the limitations of available prevention and control methods, development of a vaccine against these viruses may be the best solution in the military environment.

Caliciviridae Infections↗
PubMed2000

Chronic liver disease among U.S. military patients: the role of hepatitis C and G virus infection.

Thirty-nine patients with chronic liver disease who were being evaluated in a U.S. military treatment facility were tested for antibody to hepatitis C virus (anti-HCV) and for hepatitis G virus (HGV) RNA by reverse transcriptase-polymerase chain reaction. Serum samples from 20 patients (51%) were positive for anti-HCV by immunoblot assay. HGV RNA was found in the sera of only two patients, both of whom were also positive for anti-HCV. HGV appears to have a limited role in causing chronic liver disease in this population of military patients, many of whom had traveled outside the United States. However, HCV infection was commonly associated with chronic hepatitis and cirrhosis, as in civilian patients.

Adult↗
PubMed1999

Remote village survey for agents causing hepatosplenic disease in the Republic of Yemen.

The objective of this study was to epidemiologically describe potential infectious agents among rural people in the Republic of Yemen. This would aid clinicians in designing empirical therapy and public health officials in planning disease prevention. We sought to examine evidence for the geographical distribution of pathogens causing human hepatic and splenic disease among villagers and domestic animals living in three remote areas with differing altitudes. In June 1992, a cross-sectional survey was conducted at three survey sites of differing altitudes: 3080, 1440 and 250 m above sea level. Questionnaires, parasitic and serological tests were administered to 627 human volunteers. Additionally 317 domestic animals were studied. Malaria, schistosomiasis, and hepatitis B and C infections were found to be likely causes of human hepatic or splenic disease. Additionally, evidence of human and animal infections with the agents of brucellosis and Q fever was found: IgG antibodies against hepatitis E virus were discovered in two (2.0%) of the 100 volunteers. The prevalence of markers for human and animal disease was often lowest at the village of highest elevation, suggesting that increasing altitude, as a surrogate or a true independent risk factor, was protective against infection with the agents studied.

Adolescent↗
PubMed1999

Risk of Helicobacter pylori infection among long-term residents in developing countries.

The seroprevalence and incidence of Helicobacter pylori infection were determined among 312 North American missionaries who were serving in developing countries between 1967 and 1984. The majority (81%) resided in sub-Saharan Africa. When initially evaluated, the missionaries had a mean age of 40 years, 65% were female, and all were of white race/ethnicity. An ELISA showed that the initial prevalence of IgG antibody to H. pylori was 17%. After a mean of 7.4 years of service (1917 person-years of exposure), 37 (14%) of 259 initially seronegative subjects seroconverted to anti-H. pylori, giving an annual incidence of 1.9%. These data indicate a relatively higher risk of H. pylori infection among missionaries compared with an annual incidence of seroconversion of 0.3-1.0% in industrialized nations. Long-term residents in developing countries should be evaluated for H. pylori infection when gastrointestinal symptoms develop.

Adult↗
PubMed1999

Prevalence of enteric hepatitis A and E viruses in the Mekong River delta region of Vietnam.

A study of antibody prevalence for hepatitis A virus (HAV) and hepatitis E virus (HEV) was carried out in southwestern Vietnam in an area adjacent to a known focus of epidemic HEV transmission. The purpose of this investigation was first to provide a prevalence measure of hepatitis infections, and second to determine the outbreak potential of HEV as a function of the susceptible population. Blood specimens collected from 646 persons in randomly selected village hamlets were examined by an ELISA for anti-HEV IgG and anti-HAV IgG. The prevalences of anti-HEV IgG and anti-HAV IgG were 9% and 97%, respectively. There was a significant increase (P < 0.01) in age-specific anti-HEV IgG. A notable increase in anti-HAV IgG prevalence (P < 0.0001) occurred between child populations 0-4 (64%) and 5-9 (95%) years of age. No evidence of familial clustering of anti-HEV IgG-positive individuals was detected, and household crowding was not associated with the spread of HEV. Boiling of water was found to be of protective value against HEV transmission. A relatively low prevalence of anti-HEV indicates considerable HEV outbreak potential, against a background of 1) poor, water-related hygiene/sanitation, 2) dependence on a (likely human/animal waste)-contaminated Mekong riverine system, and 3) periodic river flooding.

Adolescent↗
PubMed1999

Seroprevalence of Helicobacter pylori among Egyptian newborns and their mothers: a preliminary report.

Helicobacter pylori is one of the most common human bacterial infections in the world and children in the developing countries acquire H. pylori infection early in life. We prospectively evaluated the prevalence of serum antibodies to H. pylori in a cohort of pregnant women and their offspring. Mothers' sera were collected during the third trimester of pregnancy and sera from their offspring were collected when they were 7-9 months and 18 months of age. Pylori-Stat, a commercially available ELISA kit, was used to detect antibodies to H. pylori in the serum of the subjects tested. Sera from 169 mothers were available for testing and 88% of these samples were positive for anti-H. pylori IgG. Of the 169 children tested, 13% of the infants 7-9 months of age and 25% of the children 18 months of age had serologic evidence of H. pylori infection. These data indicate that infection with H. pylori is common in Egypt and acquisition of infection occurs at a very young age.

Adolescent↗
PubMed1998

Acute jaundice in Vientiane, Lao People's Democratic Republic.

Analysis of serum samples from patients with acute jaundice by means of enzyme-linked immunosorbent assay and polymerase chain reaction testing provided the first profile of this condition in Vientiane, Lao PDR, in 1995 and 1996. In a case-control, hospital-based study, evidence of acute infections due to hepatitis A and B viruses was found in 14% and 10% of cases, respectively. Hepatitis E virus, however, did not appear to contribute to clinically recognized acute jaundice. Similarly, antibody to hepatitis C virus was recognized in almost equal proportions of cases (8%) and controls (6%), thus representing probable background infections. The detection of hepatitis G virus marks the first report of this virus in Lao PDR. The large proportion (21%) of new leptospiral infections in cases without acute hepatitis A or B was notable. This finding suggests significant regional underreporting of leptospirosis as a cause of acute jaundice. The limited laboratory diagnostic capabilities for confirming a differential diagnosis of leptospirosis contribute to the lack of attention paid to this important health problem.

Acute Disease↗
PubMed1998

A survey of women's health care needs on U.S. Navy ships.

A total of 628 female and 526 male U.S. military personnel completed a health survey questionnaire at the completion of four shipboard deployments lasting 10 to 180 days (mean, 57 days). During deployment, women visited clinic (sick call) at significantly higher rates than men: 189 versus 117 visits per week per 1,000 personnel. Except for generally minor gynecological conditions, women and men had similar medical problems. Upper respiratory complaints and requests for contraceptive pills were the most common reasons for clinic visits among women. The majority of sailors felt that they had received appropriate medical care, although fewer women (66%) than men (78%) were satisfied. Levels of cigarette and alcohol use and sexual activity were comparable among women and men and corresponded to those of the general U.S. population of young adults. Because of high levels of health, most medical needs of women sailors can be managed readily by providing routine gynecological care and by minor additions to the shipboard pharmacy.

Adolescent↗