Factors associated with HIV prevalence in a pre-partum cohort of Zambian women.

An ongoing study of mother-to-child human herpes virus-8 (HHV-8) transmission in Zambian women (n = 3160) allowed us to examine the association of medical injections with HIV serostatus while simultaneously accounting for other factors known to be correlated with HIV prevalence. Multi-method data collection included structured interviews, medical record abstraction, clinical examinations, and biological measures. Medically administered intramuscular or intravenous injections in the past five years (but not blood transfusions) were overwhelmingly correlated with HIV prevalence, exceeding the contribution of sexual behaviours in a multivariable logistic regression. Statistically significant associations with HIV also were found for some demographic variables, sexual behaviours, alcohol use, and sexually transmitted diseases (STD). The results confirmed that iatrogenic needle exposure, sexual behaviour, demographic factors, substance use, and STD history are all implicated in Zambian women's HIV+ status. However, the disproportionate association of medical injection history with HIV highlights the need to investigate further and prospectively the role of health-care injection in sub-Saharan Africa's HIV epidemic.

Intestinal parasitic infections in human immunodeficiency virus (HIV)-positive and HIV-negative individuals in San Pedro Sula, Honduras.

Honduras has at least five-times more human immunodeficiency virus (HIV)-infected individuals than any other country in Central America. The relationship between HIV status and the presence of intestinal parasites in this part of the world is unknown. This study presents the results from a prospective, comparative study for the presence of parasites in 52 HIV-positive and 48 HIV-negative persons in San Pedro Sula, Honduras. Infection with HIV was determined by microagglutination and confirmed by Western blot analysis. Parasites were detected in stools using formalin-ether concentration, and Kinyoun and trichrome staining. Age, sex, and clinical state of HIV infection were recorded for each study participant. Our results indicate that Cryptosporidium parvum and Strongyloides stercoralis, which are intracellular or live in the mucosa, were found exclusively in persons infected with HIV. In comparison, the prevalence of the extracellular parasites Giardia lamblia, Ascaris lumbricoides, and Trichuris trichiura was significantly higher (P < 0.05) in persons who were HIV-negative. Trichuris worms are in contact with the gut epithelium and less so with the mucosa, whereas Strongyloides lives within the gut mucosa. It is possible that changes in the gut epithelium due to HIV infection do not affect the mucosa and therefore would not affect Strongyloides. We conclude that infection with HIV may selectively deter the establishment of certain intestinal parasites. This may be due to the fact that HIV-induced enteropathy does not favor the establishment of extracellular parasites. Intracellular and mucosal dwelling organisms, however, may benefit from pathologic changes and reduced local immune responses induced by the virus, which, in turn, may lead to higher prevalence among HIV-infected individuals.

Drug use and syphilis. Co-factors for HIV transmission among commercial sex workers in Guyana.

A cross-sectional survey was conducted among 124 street- and brothel-based female commercial sex workers (CSWs) in Georgetown in January and February 1997 to determine the seroprevalence of human immunodeficiency virus (HIV) infection and describe the sexual practices and drug use patterns. Their median age was 30 years (range 17 to 52 years). 119 (88%) reported regular alcohol consumption while looking for clients, 27 (22%) said they smoked cocaine and 51 (42%) reported use of marijuana. Street-based CSWs were significantly more likely to report marijuana use (p = 0.033). 72% reported that they never used condoms with regular sex partners and 35% reported that they never used condoms with clients. Brothel-based women were significantly more likely to report consistent condom use with their clients (p = 0.05). 46% (54/118) tested HIV positive and 28% (33/118) had a positive serological test for syphilis. Factors that were significantly associated with HIV infection included a positive serological test for syphilis (OR = 7.56; 95% CI = 2.7-21.97; p < 0.01) and a history of having received treatment for syphilis (OR = 2.93; 95% CI = 1.12-7.8). Weak associations were also found between HIV infection and a history of cocaine use (OR = 2.57; 95% CI = 0.95-7.11; p = 0.039); having more than four clients per night (OR = 5.14; 95% CI = 1.65-16.74; p = 0.04); and a history of receiving treatment for salpingitis (OR = 2.31; 95% CI = .93-5.75; p = 0.0035). No statistically significant association was found between HIV infection and marijuana use nor any sociodemographic variables (age, place of work, and duration of sex work). There is an urgent need for a community based behavioural intervention programme targetting this high risk population.

Prevalence of viral and bacterial sexually transmitted pathogens in Jamaican pregnant women.

In this study we investigated the prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, Treponema pallidum, human immunodeficiency virus type I (HIV-I), human T cell lymphotropic virus type 1 (HTLV-1) and hepatitis B virus (HBV) infections in 200 pregnant women attending antenatal clinics at the University Hospital of the West Indies. 19% of the women had at least one pathogen: C. trachomatis was found in 16%, HTLV-1 in 2%, HIV-1, HBV and N. gonorrhoeae each in 0.5% C. trachomatis infection was more prevalent in women less than 20 years of age (31%) than in those 20 years and older (16%; OR = 0.43; chi 2 = 5.66; p < 0.05). The study demonstrates the need for identification of sexually transmitted pathogens in antenatal women for syndromic management of genital infections as part of the strategy for prevention and control of HIV/AIDS (acquired immunodeficiency syndrome) in Jamaica.

Human herpesvirus 8 can be transmitted through blood in drug addicts.

Human Herpes virus type-8 (HHV-8) seroprevalence was studied in a population of HIV positive intravenous drug users (IVDUs) from Argentina. Analysis of this population also indirectly made it possible to study HHV-8 blood transmission, because these individuals frequently engage in needle sharing behavior and are capable of acquiring a broad array of blood borne pathogens, including Hepatitis B/C virus. The seroprevalence of HHV-8 in IVDUs was compared to a group of non-IVDUs and HIV negative individuals. Of the 223 individuals tested, 13.45% were HHV-8 positive, 16.99% in the IVDUs group, and 5.71% in the non-IVDUs. Among HIV positive IVDUs, 25/144 (17.36%) were also HHV-8 seropositive. The seropositivity rate of HHV-8 in HIV negative IVDUs was 11.1%. In contrast, HHV-8 seroprevalence in HIV negative heterosexual individuals without drug usage behavior was even lower (5.71%). The rate of HHV-8 infection in HIV positive IVDUs was three times as high compared to the non IVDU HIV negative individuals, suggesting that IVDU is a risk for HHV-8 infection. Furthermore, it was found that IVDUs showed a very high rate of Hepatitis B/C (52.77%), which also correlate with HHV-8 infection in this population (23.68%). All Hepatitis B/C positive individuals were also HIV positive. Our data confirm other studies showing that individuals who share needles are at risk for acquiring Hepatitis B/C and HIV infections. In addition, our results suggest that they are also at risk to acquiring HHV-8 infection by the same route.

Factors associated with the initiation of alpha-interferon treatment in Medicaid patients diagnosed with hepatitis C.

We aimed to determine rates of treatment with alpha-interferon medication in patients diagnosed with hepatitis C virus (HCV), to ascertain the prevalence of selected conditions that could influence initiation of interferon treatment, and to examine the association between the presence of these conditions and interferon treatment. A nested case-control design was used in California Medicaid (Medi-Cal) claims data covering the period from 1 January 1996 to 30 June 2002. Interferon-treated cases and non-treated controls were selected in a 1 : 2 ratio that matched the length of the observation period and year of index HCV diagnosis. Predictor variables examined in bivariate and multivariate analyses included demographics, substance abuse and dependence, psychotropic drug use, selected chronic conditions and medical utilization. The proportion of eligible subjects diagnosed with HCV and treated with interferon ranged from 10.7 to 13.9%. There were 529 treated cases that met the eligibility criteria and 1058 non-treated HCV patients selected as controls. Multivariate factors that increased the likelihood of treatment were a liver biopsy, a diagnosis of mild liver disease, a diagnosis of psoriasis, antidepressant use and classification of race/ethnicity as 'other'. A decreased likelihood of treatment was linked to age > or =65 years, a diagnosis of kidney disease, one to four emergency visits and five or more emergency visits. The proportion of patients receiving interferon treatment in the Medi-Cal-insured population was low compared with published rates in HCV patients in other general medical settings. The diverse factors linked to initiation of HCV therapy raise compelling questions for further research.

Epidemiological characteristics of human herpesvirus-8 infection in a large population of antenatal women in Zambia.

Comprehensive data describing epidemiological characteristics of the human herpesvirus-8 or Kaposi's sarcoma-associated herpesvirus (HHV-8 or KSHV) infection among pregnant women in a central sub-Saharan Africa are not available. This study determined virus prevalence estimates and the risk factors associated with HHV-8 infection. Cross-sectional, enrollment visit data were analyzed from a prospective cohort study of perinatal transmission of HHV-8 in Lusaka, Zambia. Exposure data were obtained via structured interview, physical examination, medical chart review, and laboratory testing. Among 3,160 antenatal women serologically screened for HHV-8 between September 1998 and October 2000, 40.2% were seropositive. The HHV-8 positive women were more likely to be co-infected with HIV-1 than those who were HHV-8 negative (34% vs. 26%; P < 0.0001). Of 154 variables evaluated by logistic regression analyses, only three risk factors, have emerged as independent predictors of HHV-8 positive serology: diagnosis of genital warts, HIV-1 co-infection and primary education. The association of HHV-8 infection with genital warts and HIV-1 co-infection suggests heterosexual transmission of HHV-8. HIV-1 infection may also act as a marker for particular behaviors, which could be sexual in nature, that are associated with both HIV-1 and HHV-8 transmission. Since HHV-8 facilitates development of AIDS-related Kaposi's sarcoma (KS), the results of this study could be utilized to identify specific population groups of pregnant women who are at increased risk for this disease.

Prevalence, incidence, and risks for HIV-1 infection in female sex workers in Miami, Florida.

Annual cross-sectional prevalence, incidence of new infection, and risks for human immunodeficiency virus type 1 (HIV-1) infection were studied in 607 women convicted of prostitution between October 1987 and December 1990 and tested for HIV under court order. Cross-sectional prevalence was stable for 4 years (23-24% positivity in 1987-1991, p = 0.6). However, the incidence of new infections (rate of seroconversion) in 264 women tested more than once increased significantly each year from 12 per 100 person-years in 1987-1988 to 19 per 100 person-years in 1991 (p < 0.03). Seroconverters were more likely to be young black women with a prior history of syphilis or gonorrhea. A new episode of syphilis or rectal gonorrhea during the follow-up period predicted HIV seroconversion in a survival analysis model. Female sex workers are at great risk of acquiring HIV infection. Although HIV prevalence in cross-sectional samples was stable, incidence was increasing. Interpretation of prevalence trends from convenience samples, such as screening programs, may be difficult because changes in incidence may not be detected.

Comparison of quality of life, work productivity and medical resource utilization of peginterferon alpha 2a vs the combination of interferon alpha 2b plus ribavirin as initial treatment in patients with chronic hepatitis C.

The on-treatment impact of interferon-based therapies on quality of life (QOL), work productivity, and medical resource utilization has not been systematically studied. We evaluated the effects of treatment with peginterferon alpha (pegIFNalpha) 2a monotherapy and the combination of interferon alpha (IFNalpha) 2b plus ribavirin (RBV) on health-related QOL, work productivity and resource utilization. A total of 412 patients with hepatitis C infection were randomized to open-label treatment with either pegIFNalpha 2a (n = 206) or IFNalpha 2b/RBV (n = 206). PegIFNalpha 2a was administered subcutaneously at a dose of 180 microg once weekly for 48 weeks; and IFNalpha 2b/RBV at doses of 3 MU thrice weekly subcutaneously and 1000-1200 mg/day orally. Outcome measures included the SF-36 Health Survey Questionnaire and additional generic and specific scales. During treatment, for all SF-36 summary and Hepatitis Quality of Life Questionnaire (HQLQ)-specific scales, the pegIFNalpha 2a group experienced less impairment than did the IFNalpha 2b/RBV patients. The between-treatment differences were significant for many of the scores particularly in the first 24 weeks of treatment. Across all measures of work functioning and productivity at each visit, patients randomized to pegIFNalpha 2a treatment showed less impairment relative to the group treated with IFNalpha 2b/RBV. Hence treatment with pegIFNalpha 2a relative to IFNalpha 2b/RBV minimizes the adverse impact of therapy on health-related QOL. Patients randomized to pegIFNalpha 2a had improved work productivity, less activity impairment, decreased need for prescription drugs to treat adverse effects, and better adherence to therapy.

Increased prevalence of Plasmodium falciparum malaria in Honduras, Central America.

We report on our investigation of a malaria outbreak in Honduras, Central America, in January 1997. We tested 202 patients with fever and chills using thin and thick blood film microscopy. Sixteen patients lived in the city and the rest lived in rural areas. A total of 95 samples (47%) were positive for malaria parasites. Seventy-nine percent (63/80) of the rural patients were infected with Plasmodium vivax and 21% (17/80) were infected with P. falciparum. In the urban area, all 15 infected patients had P. vivax malaria and none showed evidence of P. falciparum. Since previous reports indicate that falciparum malaria accounts for only 2% of the overall malaria infections in Honduras, the results reported here suggest that there is a dramatic increase in falciparum malaria in the area of Honduras investigated in this study.

Human herpesvirus 8 as a potential sexually transmitted agent in Honduras.

The seroprevalence of human herpesvirus 8 (HHV-8) was studied in 326 human immunodeficiency virus (HIV)-positive and -negative persons from Honduras; women constituted 77% (n = 251) of the subjects. Sera were tested for lytic HHV-8 antibodies by an IFA, and positive samples were confirmed by a radioimmunoprecipitation assay. Of the 326 persons tested, 58 (17.8%) had HHV-8 antibodies. Among the HIV-infected women, 22.7% were seropositive; 11.3% of the HIV-negative women were seropositive. HHV-8 seroprevalence was almost four times higher in HIV-positive female commercial sex workers (36%) than in HIV-negative female non-commercial sex workers (9.9%; odds ratio = 3.8, 95% confidence interval = 1.1-13; P = 0.01), suggesting that commercial sex work is a risk factor for HHV-8 infection. In the men studied, the overall HHV-8 seroprevalence was 22.6%, with a seropositivity rate of 28% for HIV-positive men compared with 12% for HIV-negative men.

Vertical transmission of Kaposi's sarcoma-associated herpesvirus.

Little is presently known about the specific routes of transmission of Kaposi's sarcoma-associated herpesvirus (KSHV) or human herpesvirus-8 (HHV-8). To investigate whether this agent might be transmitted vertically from mother to infant, we conducted a study on 89 KSHV seropositive mothers and their newborn infants. Thirteen mothers (14.6%) had KSHV DNA detected in their peripheral blood mononuclear cells (PBMC). Two of 89 samples drawn at birth from infants born to KSHV seropositive mothers had KSHV DNA detectable within their PBMC. These findings suggest that KSHV can be transmitted perinatally, but infrequently. Other routes of transmission such as horizontal transmission remain the most likely means of KSHV transmission.

HIV-related high risk sexual behaviors and practices among women in Bogotá, Colombia.

Determinants associated with high-risk sexual behaviors were investigated in 1,133 sexually active women in Bogotá, Colombia. A self-administered questionnaire was completed by two groups of women: 721 representing the general population (GP), and 412 commercial sex workers (CSWs). High-risk sexual behaviors for HIV/AIDS were evident in both groups. Nevertheless, consistent condom use was reported by only 6% of the GP group, as compared to 67% of the CSWs. Failure to recognize high-risk routes for HIV infection was indicated in 69% of the GP women for anal sex, and by the majority of both groups for intercourse during menses (56% GP women and 54% CSWs). Multivariate analysis revealed that education level, actual age, and age of first sex experience were significant predictors of high-risk sexual practices. The necessity for educational programs regarding high-risk sexual practices and risk of HIV/ AIDS is evident for HIV/AIDS prevention.

Evaluation of the OptiMAL test for rapid diagnosis of Plasmodium vivax and Plasmodium falciparum malaria.

The development of rapid and specific diagnostic tests to identify individuals infected with malaria is of paramount importance in efforts to control the severe public health impact of this disease. This study evaluated the ability of a newly developed rapid malaria diagnostic test, OptiMAL (Flow Inc., Portland, Oreg.), to detect Plasmodium vivax and Plasmodium falciparum malaria during an outbreak in Honduras. OptiMAL is a rapid (10-min) malaria detection test which utilizes a dipstick coated with monoclonal antibodies against the intracellular metabolic enzyme parasite lactate dehydrogenase (pLDH). Differentiation of malaria parasites is based on antigenic differences between the pLDH isoforms. Since pLDH is produced only by live Plasmodium parasites, this test has the ability to differentiate live from dead organisms. Results from the OptiMAL test were compared to those obtained by reading 100 fields of traditional Giemsa-stained thick-smear blood films. Whole-blood samples were obtained from 202 patients suspected of having malaria. A total of 96 samples (48%) were positive by blood films, while 91 (45%) were positive by the OptiMAL test. The blood films indicated that 82% (79 of 96) of the patients were positive for P. vivax and 18% (17 of 96) were infected with P. falciparum. The OptiMAL test showed that 81% (74 of 91) were positive for P. vivax and 19% (17 of 91) were positive for P. falciparum. These results demonstrated that the OptiMAL test had sensitivities of 94 and 88% and specificities of 100 and 99%, respectively, when compared to traditional blood films for the detection of P. vivax and P. falciparum malaria. Blood samples not identified by OptiMAL as malaria positive normally contained parasites at concentrations of less than 100/microl of blood. Samples found to contain P. falciparum were further tested by two other commercially available rapid malaria diagnostic tests, ParaSight-F (Becton Dickinson, Cockeysville, Md.) and ICT Malaria P.f. (ICT Diagnostics, Sydney, Australia), both of which detect only P. falciparum. Only 11 of the 17 (65%) P. falciparum-positive blood samples were identified by the ICT and ParaSight-F tests. Thus, OptiMAL correctly identified P. falciparum malaria parasites in patient blood samples more often than did the other two commercially available diagnostic tests and showed an excellent correlation with traditional blood films in the identification of both P. vivax malaria and P. falciparum malaria. We conclude that the OptiMAL test is an effective tool for the rapid diagnosis of malaria.

Cost-effectiveness of combination peginterferon alpha-2a and ribavirin compared with interferon alpha-2b and ribavirin in patients with chronic hepatitis C.

BACKGROUND: Sustained virological response (SVR) is the primary objective in the treatment of chronic hepatitis C (CHC). Results from a recent clinical trial of patients with previously untreated CHC demonstrate that the combination of peginterferon alpha-2a and ribavirin produces a greater SVR than interferon alpha-2b and ribavirin combination therapy. However, the cost-effectiveness of peginterferon alpha-2a plus ribavirin in the U.S. setting has not been investigated. METHODS: A Markov model was developed to investigate cost-effectiveness in patients with CHC using genotype to guide treatment duration. SVR and disease progression parameters were derived from the clinical trials and epidemiologic studies. The impact of treatment on life expectancy and costs were projected for a lifetime. Patients who had an SVR were assumed to remain virus-free for the rest of their lives. In genotype 1 patients, the SVRs were 46% for peginterferon alpha-2a plus ribavirin and 36% for interferon alpha-2b plus ribavirin. In genotype 2/3 patients, the SVRs were 76% for peginterferon alpha-2a plus ribavirin and 61% for interferon alpha-2b plus ribavirin. Quality of life and costs were based on estimates from the literature. All costs were based on published U.S. medical care costs and were adjusted to 2003 U.S. dollars. Costs and benefits beyond the first year were discounted at 3%. RESULTS: In genotype 1, peginterferon alpha-2a plus ribavirin increases quality-adjusted life expectancy (QALY) by 0.70 yr compared to interferon alpha-2b plus ribavirin, producing a cost-effectiveness ratio of $2,600 per QALY gained. In genotype 2/3 patients, peginterferon alpha-2a plus ribavirin increases QALY by 1.05 yr in comparison to interferon alpha-2b plus ribavirin. Peginterferon alpha-2a combination therapy in patients with HCV genotype 2 or 3 is dominant (more effective and cost saving) compared to interferon alpha-2b plus ribavirin. Results weighted by genotype prevalence (75% genotype 1; 25% genotype 2 or 3) also show that peginterferon alpha-2a plus ribavirin is dominant. Peginterferon alpha-2a and ribavirin remained cost-effective (below $16,500 per QALY gained) under sensitivity analyses on key clinical and cost parameters. CONCLUSION: Peginterferon alpha-2a in combination with ribavirin with duration of therapy based on genotype, is cost-effective compared with conventional interferon alpha-2b in combination with ribavirin when given to treatment-naïve adults with CHC.