Molecular cloning and disease association of hepatitis G virus: a transfusion-transmissible agent.

An RNA virus, designated hepatitis G virus (HGV), was identified from the plasma of a patient with chronic hepatitis. Extension from an immunoreactive complementary DNA clone yielded the entire genome (9392 nucleotides) encoding a polyprotein of 2873 amino acids. The virus is closely related to GB virus C (GBV-C) and distantly related to hepatitis C virus, GBV-A, and GBV-B. HGV was associated with acute and chronic hepatitis. Persistent viremia was detected for up to 9 years in patients with hepatitis. The virus is transfusion-transmissible. It has a global distribution and is present within the volunteer blood donor population in the United States.

Inappropriate urine cultures in hospitalized patients receiving antibiotic therapy.

To investigate the effect of concurrent antibiotic therapy on bacterial isolation, 1001 consecutive urine cultures obtained from hospitalized patients were evaluated. Of the cultures, 121 (12.1%) had positive results. The administration of antibiotic therapy substantially changed urine culture results in uncatheterized patients. Only one (0.7%) of 135 cultures obtained from patients without a recent history of catheterization was positive when antibiotics were being administered. In contrast, 43 (8.6%) of 501 urine cultures obtained from uncatheterized patients not receiving antibiotic therapy were positive. These results indicate that concurrent antibiotic therapy should be considered before ordering urine cultures in uncatheterized patients. Substantial savings would result if, in this situation, cultures were limited to patients with urinary tract symptoms or a history of urinary tract pathology.

Tuberculosis infection among young adults entering the US Navy in 1990.

BACKGROUND: From 1958 through 1969, more than 1.2 million US Navy recruits received tuberculin skin tests; 5.2 per 100 were tuberculin reactors. Subsequent analyses predicted a downward trend in the risk of tuberculosis infection in the United States. We sought to determine the current prevalence of tuberculin reactors by sex, race/ethnic group, and birthplace among young adult residents of the United States entering the US Navy. METHODS: Recruits routinely receive a tuberculin skin test on entering US Navy recruit training in Great Lakes, Ill, Orlando, Fla, or San Diego, Calif. In January and February 1990, 2416 young men and women (mean age, 20.6 years) received tuberculin skin tests and completed questionnaires eliciting demographic and tuberculosis risk factor data. A tuberculin reactor was defined as a subject having 10 mm or greater induration to a skin test with 5 tuberculin units, purified protein derivative, administered intradermally by the Mantoux method. RESULTS: Fifty-five of 2214 men (2.5 per 100; 95% confidence interval, 1.9 to 3.2 per 100) and five of 202 women (2.5 per 100; 95% confidence interval, 0.8 to 5.8 per 100) were tuberculin reactors. For men, the prevalence was greater in blacks (5.2 per 100), Hispanics (5.4 per 100), and Asian/Pacific Islanders (26.4 per 100) than in whites (0.8 per 100) and greater in foreign-born recruits (19.2 per 100) than in recruits born in the United States (1.6 per 100). Women had the same pattern of prevalence by race/ethnic group and birthplace. CONCLUSIONS: The prevalence of tuberculosis reactors declined as predicted among young adults, especially the white US-born recruits, entering the US Navy. Although the prevalence also declined among nonwhites and the foreign-born recruits, a substantial proportion continue to enter adulthood with preexisting tuberculosis infection.

The epidemiology of HIV-1 infection in Peru, 1986-1990.

OBJECTIVE: To determine the extent of the HIV-1 epidemic in Peru. DESIGN: Part of a national serosurvey in Peru. METHODS: Between January 1986 and December 1990, 140,976 serum samples were tested for HIV-1 antibody. RESULTS: HIV-1 antibody was found in a high percentage of serum samples provided by 4300 homosexual men (26%), 2204 male sexually transmitted disease patients (10%), 145 drug users (13%), 269 hemophiliacs (10%), and 146 unlicensed female prostitutes (10%). In addition, the prevalence of HIV-1 infection increased substantially among these groups between the beginning and end of the survey period. A low but rising prevalence of HIV-1 antibody was found during this period among serum samples provided by 83,526 blood donors and 11,101 military personnel:total period prevalence, 0.25 and 0.32%, respectively. CONCLUSION: These data indicate that HIV-1 infection is epidemic in Peru among groups at high risk of sexually and parenterally transmitted diseases, and that the risk of infection appears to be low but possibly increasing among the general population.

PIP: The findings of a national seroprevalence survey conducted in Peru during 1986-90 indicate accelerating rates of human immunodeficiency virus (HIV) among population groups at high risk of sexually transmitted diseases. Two databases were maintained: 1) January 1986-December 1988 and 2) January 1989-December 1990. Of the 140,976 survey participants, 3345 (2.4%) were HIV-positive by Western blot. 2591 participants were selected because of clinical signs suggestive of acquired immunodeficiency syndrome (AIDS); 46.7% were HIV-positive, but the prevalence increased from 19% in the 1986-88 period to 60% during 1989-90. Among the 4300 men who identified themselves as homosexual or bisexual, 26% were seropositive (8% during 1986-88 and 41% during 1989-90). HIV prevalence among 2204 men attending a sexually transmitted diseases clinic was 10.3%, with an increase from 2.0% in the first period to 19.0% in the later period. 10.4% of the 269 hemophiliacs were HIV-infected, with an increase from 8% to 36%. Among the 145 intravenous drug users, the prevalence rose from 1% during 1986-88 to 27% during 1989-90. Among 5827 registered female prostitutes, the prevalence rose from 0.3% to 0.7%; however, a 1990 analysis of 146 unregistered prostitutes revealed a rate of 9.6%. The HIV rates among 285 female and 105 male heterosexual partners of known HIV-positive persons were 50.2% and 40.0%, respectively. HIV prevalence increased from 0.8% during 1986-88 to 8.0% during 1989-90 among 1532 men and 1247 women who requested anonymous HIV testing. The prevalence among 542 male and 615 female medical personnel was 2.3%. Among 78,793 volunteer and 4733 paid blood donors, HIV prevalence was 0.2% (0.3% among paid donors). The period prevalence among 11,101 male military recruits and active duty members increased from 0.009% to 0.5%. Finally, only 0.3% of 21,595 applicants for immigration visas were HIV-positive, and there were no HIV cases among 1234 pregnant women attending antenatal clinics. Although the very low HIV prevalence among military personnel and pregnant women suggests that the virus is not yet widely disseminated within the general population, the finding that 28% of HIV-positive men were married and engaged in bisexual behavior suggests potential for heterosexual transmission in the years ahead.

HIV-1 and hepatitis B transmission in Sudan.

A seroepidemiologic survey was conducted among 773 male soldiers living in five urban locations in Sudan to study the prevalence of and risk factors for HIV-1 and hepatitis B transmission. Twenty-eight per cent of the study population were born and raised in southern Sudan, an area bordering Kenya, Zaire and Uganda, whilst 72% of the study subjects were from northern Sudan. Seventy-eight per cent of the study population had serologic evidence of past hepatitis B infection, and 13 soldiers were confirmed positive for HIV-1 antibody. All 13 HIV-positive soldiers had recently been deployed in southern Sudan. Multivariate analysis indicated an association between living in southern Sudan and both hepatitis B (odds ratio 8.2) and HIV-1 infection (odds ratio 14). Additionally, sexual relations with prostitutes (odds ratio 1.5) and medical injections for schistosomiasis (odds ratio 2.72) were independent predictors of hepatitis B markers in this military population. The findings of this study suggest that sexual promiscuity is a risk factor for hepatitis B transmission in Sudan. They also indicate one possible route for the spread of HIV-1 from central to northern Africa.

Three-year incidence study of retroviral and viral hepatitis transmission in a Peruvian prostitute population.

A Peruvian female prostitute population was evaluated over a 3-year period to determine the incidence and risk factors of retroviral and viral hepatitis transmission. At three survey periods, a questionnaire was administered and serum samples were obtained. A total of 966 subjects were studied, with 34% followed for 38 months, 22% followed for 18 months, and 44% evaluated just once. On initial evaluation, 3 (0.3%) had HIV-1 antibody, 170 (17.6%) had HTLV-I antibody, 578 (59.8%) had anti-HBc, and 7 (0.7%) had antibody to hepatitis C virus. The mean annual incidence of HTLV-I and hepatitis B infection was 1.6% and 4.7%, respectively. Univariate and logistic regression analysis of prevalence data indicated an association between sexual activity and HTLV-I and hepatitis B infection, but no independent risk factors were identified in cohort analysis. Parenteral risk factors were not associated with transmission, except for a small percentage of subjects who may have acquired hepatitis B infection from blood transfusions. These findings suggest that there is a high incidence of HTLV-I and hepatitis B infection from heterosexual contact in this female prostitute population.

Comparative evaluation of six rapid serological tests for HIV-1 antibody.

Six commercial rapid test kits for HIV-1 antibody were evaluated. Four laboratory technologists tested sera from four groups of U.S. military personnel or dependents: 202 subjects positive for HIV-1 antibody by Western blot, 200 seronegative voluntary blood donors, 199 seronegative obstetrics/gynecology patients, and 99 subjects with sera reactive by ELISA but negative by recombinant protein EIA and indeterminate by Western blot. The three tests using solid-phase immunoassay technology demonstrated the highest mean sensitivity (> 99%) and specificity (> 91%) for all groups tested, including sera indeterminate by Western blot. Two dot-immunoblot assays were less specific, possibly due to indistinct reaction end points, and a latex agglutination assay was also less specific because of difficulty distinguishing reactive results from the granular background. In an "ease-of-use" assessment, solid-phase capture immunoassays required less time and equipment and were easier to interpret than other testing methods. Solid-phase capture immunoassays for HIV-1 antibody may be suitable for use in emergency situations and in developing countries because they are highly sensitive and specific and are rapidly performed with minimal laboratory equipment.

The potential effect of global warming on the geographic and seasonal distribution of Phlebotomus papatasi in southwest Asia.

The distribution of Phlebotomus papatasi in Southwest Asia is thought to be highly dependent on temperature and relative humidity. A discriminant analysis model based on weather data and reported vector surveys was developed to predict the seasonal and geographic distribution of P. papatasi in this region. To simulate global warming, temperature values for 115 weather stations were increased by 1 degree C, 3 degrees C, and 5 degrees C, and the outcome variable coded as unknown in the model. Probability of occurrence values were then predicted for each location with a weather station. Stations with positive probability of occurrence values for May, June, July, and August were considered locations where two or more life cycles of P. papatasi could occur and which could support endemic transmission of leishmaniasis and sandfly fever. Among 115 weather stations, 71 (62%) would be considered endemic with current temperature conditions; 14 (12%) additional stations could become endemic with an increase of 1 degree C; 17 (15%) more with a 3 degrees C increase; and 12 (10%) more (all but one station) with a 5 degrees C increase. In addition to increased geographic distribution, seasonality of disease transmission could be extended throughout 12 months of the year in 7 (6%) locations with at least a 3 degrees C rise in temperature and in 29 (25%) locations with a 5 degrees C rise.

Interpreting a single antistreptolysin O test: a comparison of the "upper limit of normal" and likelihood ratio methods.

Single serologic tests may occasionally influence clinicians in making diagnoses. The antistreptolysin O (ASO) test is a frequently used tool for detecting recent Streptococcus pyogenes infection and is helpful in the diagnosis of diseases like rheumatic fever. Using data from a 1989 prospective study of 600 healthy male military recruits, in which 43% experienced S. pyogenes upper respiratory tract infection (2-dilution rise in ASO), this report compared two methods of interpreting a single ASO titer. Using the "upper limit of normal" (80 percentile) method, recruits with an ASO titer of greater than 400 showed evidence of recent S. pyogenes infection. This method had a sensitivity and specificity of only 65.9 and 81.9% respectively. In contrast to the "yes-no" dichotomy of the "upper limit of normal" method, the likelihood ratio method statistics were ASO value specific, more consistent with clinical judgment, and better emphasized the caution clinicians must use in interpreting a single ASO test.

Application of a rapid assay for detection of antibodies to human immunodeficiency virus in urine.

The use of rapid, simple tests to detect antibodies to human immunodeficiency virus (HIV) in urine could be valuable for several testing situations, such as in private offices, for epidemiologic surveys, and in developing countries. The authors evaluated the performance of the SUDS HIV type 1 test to detect antibody to HIV-1 peptides in urine. Test performance and applicability of the SUDS test were compared with a routine Food and Drug Administration-licensed enzyme-linked immunosorbent assay (ELISA) and Western blot using 139 serum and urine pairs collected from autopsy cases. Using a modified procedure when testing urine by the SUDS test, results indicated that a total of 15 serum/urine pairs were HIV-1 antibody positive by both the SUDS test and ELISA; all could be confirmed positive by Western blot. One sample produced discrepant results. The SUDS test produced no false-positive results when testing serum or urine, as compared with ELISA, and no false-negative results when compared with the Western blot. For optimal accuracy of detection of antibodies using urine, at least 100 microL of sample was required. By Western blot analysis, antibody profiles in urine were generally weaker than in serum, but confirmation of positivity was not compromised when larger volumes were used. The authors concluded that this rapid HIV-1 test, when used to detect antibodies to HIV-1 in urine, is accurate, easy to perform, and appropriate for use in certain testing situations.

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.

Oropouche virus transmission in the Amazon River basin of Peru.

Seroepidemiologic studies were conducted to determine the prevalence of Oropouche (ORO) viral antibody, risk factors, and the incidence of infection among residents of the Amazon region of Peru. Blood samples, as well as demographic, cultural, and medical history data, were collected from residents in a sector of the city of Iquitos and in an adjacent rural and three neotropical rain forest communities. Blood specimens were obtained approximately one year later from a cohort of the same study subjects who were negative for ORO antibody on the initial cross-sectional survey. Sera were tested for ORO IgG antibody by an enzyme-linked immunosorbent assay. Antibody prevalences were 35% for residents of the urban population, 24-46% for the forest communities, and 18% for the rural community. Antibody prevalence increased with age, and subjects who were seropositive were significantly (P = 0.001) older (mean = 33 years) than the seronegative subjects (mean = 15 years). Multivariate analysis revealed that only age, urban and forest residence, and occupation as a farmer or housekeeper remained significantly associated with seropositivity. Seroconversion data for the same populations one year later demonstrated evidence of ORO viral infection among 28% of the residents in the rural community and 2% or less in the forest and urban communities. Oropouche virus infection was significantly associated with older age (P = 0.04) in the rural community (P < 0.001). These data support prior evidence of ORO viral infection among residents of Iquitos and surrounding villages and suggest that transmission of this virus occurs continuously in the population of this area of the Amazon basin.

A high risk of hepatitis C infection among Egyptian blood donors: the role of parenteral drug abuse.

To determine the prevalence and risk factors of hepatitis C virus (HCV) infection among Egyptian blood donors, 188 consecutive adult blood donors from four hospitals and one temporary donor center located in Cairo, Egypt were evaluated. Sera were tested for HCV antibodies (anti-HCV) using second-generation enzyme-linked immunosorbent assay (ELISA) test kits. Sera that were repeatedly reactive by ELISA were further verified by a second-generation recombinant immunoblot assay (RIBA). Antibodies to HCV were detected by RIBA in 26.6% of the blood donors, which is higher than the 10-19% prevalence of antibody found in other studies of Egyptian blood donors. A history of selling blood (odds ratio [OR] = 12.1) and the use of illicit parenteral drugs (OR = 2.5) were significantly associated with anti-HCV seropositivity after controlling for age and gender. These data indicate that the use of illicit drugs may be one reason for high levels of reported HCV infection among Egyptian blood donors. These findings also indicate that Egyptian blood donors should be screened for anti-HCV and individuals who have a history of drug abuse should be deferred from donating blood.

Acute sporadic hepatitis in adults living in Cairo, Egypt.

A group of 295 adult male patients from Cairo, Egypt, with acute hepatitis were studied. Acute hepatitis A was diagnosed in 8 patients (2.7%), hepatitis B in 115 (38.9%), delta infection in 19 (6.4%) and possible Epstein-Barr virus or cytomegalovirus-mediated hepatitis in 7 patients (2.4%). The remaining 146 patients (49.5%) were considered to have hepatitis non-A non-B. The clinical presentation of the various causes of hepatitis was similar, although patients with hepatitis B and delta infection had significantly higher mean alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels than patients diagnosed as having hepatitis non-A non-B. Various risk factors for the acquisition of hepatitis were evaluated. A history of an injection for medical treatment and a history of anti-schistosomal therapy were significantly associated with delta infection when compared to patients with either hepatitis B or non-A non-B (P less than 0.05). Hepatitis non-A non-B is a major cause of acute hepatitis in adults living in Cairo, and an iatrogenic source of infection may be important in the epidemiology of delta infection.

Safety and immunogenicity of a recombinant hepatitis B vaccine in patients infected with Schistosoma mansoni.

Thirty Egyptian males, 8-31 years of age, with active Schistosoma mansoni infection and negative serologic tests for hepatitis B markers, were vaccinated with a recombinant hepatitis B vaccine (Merck's Recombivax). The vaccine was given intramuscularly in the deltoid region in three 10 micrograms doses at 0, 1, and 6 months. All patients were treated with praziquantel 2 months after the first vaccination. Sera were collected every 2 months for 12 months and tested for anti-HBs using a quantitative ELISA technique. There were no side reactions except for mild local soreness at the injection site in 3 patients. At 12 months, all subjects seroconverted (antibody levels greater than 10 mIU/mL); 24 patients (80%) developed antibody levels greater than 1,000 mIU/mL. As with a plasma-derived vaccine, antibody levels were negatively correlated with increasing spleen size. A recombinant hepatitis B vaccine was safe and immunogenic when given to patients with schistosomiasis mansoni.

Norfloxacin for the prophylaxis of travelers' diarrhea in U.S. military personnel.

Norfloxacin, an oral fluoroquinolone (dose 400 mg daily), was compared to a placebo in a double blinded randomized trial for the prophylaxis of travelers' diarrhea. The study was of U.S. Navy and Marine Corps personnel on shore leave in Alexandria, Egypt. A total of 222 subjects were available (105 norfloxacin, 117 placebo). In the placebo group, 26% (30/117) developed acute diarrhea vs. 2% (2/105) in the norfloxacin group. There were no significant side effects in either group.

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.

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.

Short-course norfloxacin and trimethoprim-sulfamethoxazole treatment of shigellosis and salmonellosis in Egypt.

In a double-blind clinical study, 109 adult Egyptian patients infected with Shigella spp. and 45 infected with Salmonella spp. were randomly assigned to three treatment groups: 1) norfloxacin in a single 800-mg dose, 2) norfloxacin, 400 mg twice a day for three days, and 3) trimethoprim (160 mg)-sulfamethoxazole (800 mg) (TMP-SMX), twice a day for three days. Among Shigella-infected patients, diarrheal symptoms had resolved in 86-97% and bacteriologic failure (repeat positive stool culture) occurred in only two patients five days after the start of the three treatment regimens. Among Salmonella-infected patients, diarrheal symptoms had resolved in 76-82% of patients and bacteriologic failure was common (18-36%) five days after the start of therapy. These data indicate that short-course therapy with either norfloxacin or TMP-SMX can be effectively used to treat shigellosis in adults in developing countries. However, for uncomplicated Salmonella spp. infection, short-course therapy with norfloxacin and TMP-SMX may not lead to a rapid resolution of symptoms or consistently eliminate this enteropathogen.

Comparative study of the immunogenicity and safety of two dosing schedules of hepatitis B vaccine in neonates.

Healthy Egyptian neonates born to hepatitis B surface antigen (HBsAg)-seronegative mothers were randomly enrolled in one of three vaccination schedules. A dose of 2.5 micrograms of recombinant HB vaccine was given at birth, two, and six months of age (group A) or two, four, and nine months of age (group B). These two groups and a third control group (group C) also were given the other routine childhood vaccines (BCG, DPT, polio, and measles). Blood samples were taken one month after the third vaccine dose in groups A (seven months of age) and B (10 months of age), and a second follow-up blood sample was taken at the age of 18 months for all three groups. Sera were tested for HBsAg and antibody to hepatitis B core antigen, and quantitatively for antibody to hepatitis B surface antigen (anti-HBs) using commercial enzyme immunoassay kits. The vaccine was well tolerated and side effects were limited to local soreness, redness, or temporary swelling. Among 590 infants who were followed-up, good (51-300 mIU anti-HBs/ml) or excellent (> 300 mIU/ml) immune responses occurred in 85% of the infants in group A and in 96% in group B. Geometric mean titers of anti-HBs at the first and second follow-up were 306 and 55 mIU/ml in group A, and 1,492 and 147 mIU/ml in group B. The recombinant HB vaccine is safe and immunogenic when given in three doses of 2.5 micrograms in either regimen, but delay of the booster dose of the vaccine until nine months after birth produced a higher immune response.