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1.
Int J STD AIDS ; 18(3): 202-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17362556

RESUMO

Observational studies have suggested that low serum beta-carotene concentrations may influence HIV-1 disease progression. However, randomized trials have not demonstrated beneficial effects of beta-carotene supplementation. To understand this discrepancy, we conducted a cross-sectional study among 400 HIV-1-seropositive women in Mombasa, Kenya, to correlate serum beta-carotene concentrations with several measures of HIV-1 disease severity. beta-Carotene concentrations were significantly associated with biologic markers of HIV-1 disease progression (CD4 count, HIV-1 plasma viral load, serum C-reactive protein [CRP] concentration, and serum albumin level). In multivariate analysis, beta-carotene concentrations below the median were associated with elevated CRP (>10 mg/l, adjusted odds ratio [aOR] 3.32, 95% confidence interval [CI] 1.99-5.53, P<0.001) and higher HIV-1 plasma viral load (for each log(10) copies/mL increase, aOR 1.38, 95% CI 1.01-1.88, P=0.04). In the context of negative findings from randomized trials of beta-carotene supplementation in HIV-1-seropositive individuals, these results suggest that low beta-carotene concentrations primarily reflect more active HIV-1 infection rather than a deficiency amenable to intervention.


Assuntos
Infecções por HIV/sangue , HIV-1/crescimento & desenvolvimento , beta Caroteno/sangue , Adulto , Proteína C-Reativa/metabolismo , Contagem de Linfócito CD4 , Estudos Transversais , Progressão da Doença , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Quênia , Carga Viral , Vitamina A/administração & dosagem , beta Caroteno/deficiência
2.
AIDS Res Hum Retroviruses ; 21(12): 1060-5, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16379611

RESUMO

There are multiple subtypes of HIV-1 circulating worldwide, but recently, subtype C has become highly prevalent, particularly in certain geographic regions. It is unclear whether the dominance of subtype C or other subtypes is due to increased fitness of certain subtypes for transmission, or a founder effect in new, rapidly growing epidemics. To examine whether the prevalence of one subtype increases over the course of an expanding epidemic that includes several circulating subtypes, we examined the distribution of HIV-1 subtypes in Kenya from 1986 to 2000. We found no evidence for an increase in the prevalence of subtype C, which remained low throughout this approximately 15-year period. Interestingly, the percentage of subtype D present in the population decreased significantly over that period, with a slight increase in subtype A. Throughout that period, intersubtype recombinant viruses were detected, including at the early stages of the epidemic. This latter finding suggests that reinfection may have occurred in high-risk groups early in the epidemic, leading to intersubtype recombinant viruses that underwent secondary spread.


Assuntos
Surtos de Doenças , Infecções por HIV/transmissão , HIV-1/classificação , Recombinação Genética , Adolescente , Adulto , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , HIV-1/genética , Humanos , Quênia/epidemiologia , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Prevalência , Análise de Sequência de DNA
3.
AIDS ; 17(1): 65-71, 2003 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-12478070

RESUMO

OBJECTIVE: To compare compliance and infant HIV-1 infection risk at 6 weeks with the Thai-CDC and HIVNET-012 antiretroviral regimens in a field setting. DESIGN: Randomized clinical trial. SETTING: Tertiary hospital antenatal clinic in Nairobi, Kenya. PARTICIPANTS: HIV-1 infected women referred from primary care clinics. INTERVENTIONS: Thai-CDC zidovudine regimen or HIVNET-012 nevirapine regimen. MAIN OUTCOME MEASURES: Women were considered compliant if they used >or= 80% of the doses. Infants were tested for HIV-1 at 6 weeks. RESULTS Seventy women were randomized to Thai-CDC and 69 to HIVNET-012 regimens. More women were compliant with the antenatal (86%) than the intrapartum (44%) Thai-CDC regimen doses ( P= 0.001). Ninety-seven per cent took the maternal and 91% gave the infant dose of the HIVNET-012 regimen (P = 0.2). Overall, 41% were compliant with the Thai-CDC regimen and 87% with the HIVNET-012 regimen ( P< 0.001). Compliance with the Thai-CDC regimen was associated with partner support of antiretroviral use [odds ratio (OR), 3.0;, 95% confidence interval (CI), 1.0-9.1] and knowledge at recruitment that antiretroviral drugs could prevent infant HIV-1 (OR, 2.9; 95% CI, 1.0-8.1). Compliance with the HIVNET-012 regimen was associated with partner notification (OR, 8.0; 95% CI, 1.5-50) and partner willingness to have HIV-1 testing (OR, 7.5; 95% CI, 1.4-40). There was a trend for a higher risk of transmission with the HIVNET-012 regimen than with the Thai-CDC regimen (22% versus 9%; P= 0.07). CONCLUSION: Compliance with the Thai-CDC and HIVNET-012 regimens was comparable to that in efficacy trials. Partner involvement, support and education on perinatal HIV-1 prevention may improve compliance and increase the number of infants protected from HIV-1 infection.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , HIV-1 , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Cooperação do Paciente , Complicações Infecciosas na Gravidez/tratamento farmacológico , Adulto , Feminino , Grupos Focais , Seguimentos , Infecções por HIV/psicologia , Infecções por HIV/transmissão , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Lactente , Nevirapina/uso terapêutico , Seleção de Pacientes , Gravidez , Cuidado Pré-Natal/métodos , Zidovudina/uso terapêutico
4.
AIDS ; 17(1): 113-8, 2003 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-12478076

RESUMO

OBJECTIVE: We examined whether HIV-1 testing using a rapid assay increases the proportion of pregnant women obtaining HIV-1 results and the uptake of perinatal HIV-1 interventions. METHODS: Pregnant women attending public health clinics in Nairobi were offered voluntary counselling and testing for HIV-1. Consenting women were randomly assigned to receive either rapid or conventional HIV-1 testing. Women randomly assigned to rapid testing were allowed to receive same-day results or to return later. The results for women randomly assigned to conventional enzyme-linked immunosorbent assay (ELISA) testing were available after 7 days. HIV-1-infected women were referred for antiretroviral prophylaxis to prevent mother-to-child transmission of HIV-1. RESULTS: Among 1282 women offered voluntary HIV-1 testing and counselling, 1249 accepted testing, of whom 627 were randomly assigned to rapid testing and 622 to conventional testing. The median duration between testing and obtaining results was 0 days for women who received rapid testing compared with 11 days for women who received conventional testing. The percentage receiving HIV-1 results was significantly higher among women who received rapid testing compared with conventional testing. Of 161 HIV-1-seropositive women, only 24 received antiretroviral prophylaxis. The uptake of perinatal HIV-1 interventions did not differ between HIV-1-seropositive women randomly assigned to rapid testing or conventional ELISA testing. CONCLUSION: Rapid HIV-1 testing significantly increased the proportion of women receiving HIV-1 results, which is important for sexual and perinatal HIV-1 prevention. The challenge remains to improve the uptake of perinatal HIV-1 interventions among HIV-1-seropositive women.


Assuntos
Sorodiagnóstico da AIDS/métodos , Infecções por HIV/diagnóstico , HIV-1 , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez/diagnóstico , Adolescente , Adulto , Algoritmos , Fármacos Anti-HIV/administração & dosagem , Aconselhamento , Feminino , Infecções por HIV/prevenção & controle , Humanos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Assistência Perinatal/métodos , Gravidez , Encaminhamento e Consulta , Fatores de Tempo
5.
AIDS ; 18(4): 615-9, 2004 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-15090766

RESUMO

BACKGROUND: Our previous studies have shown that the majority of African women were infected with multiple HIV-1 genetic variants, while in the remaining women only a single viral genotype was detected early in infection. Infection with multiple viral variants was associated with higher plasma HIV-1 RNA levels and faster CD4 T-cell decline. METHOD: Socio-behavioral characteristics, use of hormonal contraceptives, and the presence of sexually transmitted diseases were prospectively assessed at approximately monthly intervals around the time of HIV-1 acquisition in female sex workers in Kenya. We assessed the relationship between these factors and HIV-1 genetic complexity early in infection. RESULTS: One hundred and fifty-six women were included in this analysis, of whom 89 had multiple viral genotypes and 67 had a single genotype at primary infection. Women with multiple variants were more likely to have a genital tract infection [odds ratio (OR), 4.7; 95% confidence interval (CI), 1.4-18.1] or to be using hormonal contraceptives (OR, 2.7; 95% CI, 1.3-5.6) at the time of their infection than those with a single variant. In multivariate analyses, these factors were independent predictors of early HIV-1 genetic complexity, and the presence of multiple viral variants early in infection remained significantly associated with a higher steady state plasma HIV-1 RNA level. CONCLUSION: The presence of genital tract infections and hormonal contraceptive use at the time of transmission were associated with the acquisition of multiple HIV-1 variants.


Assuntos
Variação Genética , Infecções por HIV/virologia , HIV-1/genética , Adulto , Anticoncepcionais Orais Hormonais , Métodos Epidemiológicos , Feminino , Doenças dos Genitais Femininos/complicações , Genótipo , Infecções por HIV/complicações , Infecções por HIV/transmissão , HIV-1/classificação , Humanos , Pessoa de Meia-Idade , Trabalho Sexual , Infecções Sexualmente Transmissíveis/complicações , Carga Viral
6.
AIDS ; 18(2): 205-9, 2004 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-15075537

RESUMO

OBJECTIVE: A previous cross-sectional study reported that hormonal contraception may be associated with increased infectivity in HIV-1 infected women. We conducted a prospective study to determine if cervical shedding of HIV-1 increased after initiating hormonal contraception. DESIGN: Shedding of HIV-1 DNA (a marker of HIV-1 infected cells) and HIV-1 RNA were measured before and after initiating hormonal contraception. METHODS: HIV-1 seropositive women were recruited from a Kenyan family planning clinic. At baseline, cervical secretions were collected for HIV-1 DNA and RNA assays in women initiating hormonal contraception; follow-up samples were collected a median of 64 days later. RESULTS: One-hundred and one women chose depot medroxyprogesterone (Depo), 53 chose low-dose oral contraceptives (OC), seven high-dose OC, and 52 progesterone-only OC. At follow-up, there was a significant increase in the prevalence of cervical HIV-1 DNA detection [from 42% to 52%, odds ratio (OR), 1.62; 95% confidence interval (CI), 1.03-2.63) for all hormonal contraception combined, and a trend for an increase for each individual type. Although the prevalence of cervical HIV-1 RNA increased slightly (from 82% to 86%; OR, 1.56; 95% CI, 0.83-3.03), the concentration of cervical HIV-1 RNA did not change significantly overall (from 2.81 to 2.84 log10 copies/swab; P = 0.77) or for individual contraception types. CONCLUSIONS: A modest but significant increase in shedding of HIV-1 DNA but not of HIV-1 RNA was detected after starting hormonal contraception. Our results may have important implications regarding the infectivity of women using hormonal contraception, and highlight the need for epidemiologic studies of transmission rates from women using and not using hormonal contraception.


Assuntos
Anticoncepcionais Orais Hormonais/farmacologia , Soropositividade para HIV/virologia , HIV-1/efeitos dos fármacos , Acetato de Medroxiprogesterona/farmacologia , Eliminação de Partículas Virais/efeitos dos fármacos , Adolescente , Adulto , Colo do Útero/química , DNA Viral/análise , Feminino , Seguimentos , Humanos , Estudos Prospectivos , RNA Viral/análise
7.
AIDS ; 16(15): 2073-8, 2002 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-12370507

RESUMO

BACKGROUND: Several studies have suggested that sexual transmission of human herpesvirus 8 (HHV-8) occurs among homosexual men in developed countries. However, few studies have examined heterosexual HHV-8 transmission, especially among African populations in which HHV-8 is endemic. OBJECTIVES: To determine the seroprevalence and correlates of HHV-8 infection among heterosexual African men. DESIGN: Cross-sectional study. METHODS: Participants were 1061 men enrolled in a prospective cohort study of risk factors for HIV-1 acquisition among trucking company employees in Mombasa, Kenya. Stored frozen sera from the study baseline visit were tested for antibodies to HHV-8 by whole-virus lysate ELISA. RESULTS: HHV-8 seroprevalence was 43%. In multivariate logistic regression analysis, HHV-8 infection was independently associated with older age [for men aged 30-39 years: odds ratio (OR), 1.5; 95% confidence interval (CI), 1.1-2.0; for men aged > or = 40 years: OR, 1.7; 95% CI, 1.1-2.7, compared with men aged < 30 years], Christian religion (OR, 1.6; 95% CI, 1.2-2.1), being uncircumcised (OR, 1.5; 95% CI, 1.0-2.2), and ever having syphilis (OR, 2.2; 95% CI, 1.4-3.5). Ever having used condoms was associated with decreased likelihood of infection (OR, 0.7; 95% CI, 0.6-1.0). Seropositivity was not significantly related to other sexual behaviors characterized or to HIV-1 status. CONCLUSIONS: HHV-8 seropositivity is common in this population and increases with age, suggesting on-going transmission during adulthood. Infection was more common among men who were uncircumcised or who had ever had syphilis and was less common among those who had ever used condoms, suggesting that sexual factors may play a role in HHV-8 transmission. Prospective studies of HHV-8 acquisition in heterosexual African populations are needed to demonstrate whether safer sexual practices can reduce transmission.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Herpesviridae/transmissão , Herpesvirus Humano 8/imunologia , Heterossexualidade , Doenças Virais Sexualmente Transmissíveis/transmissão , Adulto , Circuncisão Masculina , Estudos Transversais , Infecções por Herpesviridae/virologia , Humanos , Quênia , Masculino , Estudos Prospectivos , Fatores de Risco , Estudos Soroepidemiológicos , Comportamento Sexual , Doenças Virais Sexualmente Transmissíveis/virologia
8.
AIDS ; 16(18): 2425-30, 2002 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-12461416

RESUMO

OBJECTIVE: To investigate the association between the cervical shedding of herpes simplex virus (HSV) and HIV-1. DESIGN: A cross-sectional study on 200 women seropositive for both HSV-2 and HIV-1 was conducted in a family planning clinic at the Coast Provincial General Hospital, Mombasa, Kenya. MAIN OUTCOME MEASURES: Quantities of HSV DNA (types 1 and 2) and HIV-1 RNA as well as the presence or absence of HIV-1 proviral DNA in cervical secretions were determined and compared. RESULTS: There was a significant correlation between the quantities of HSV DNA and HIV-1 RNA in the cervical secretions of HSV-shedding women (Pearson's r = 0.24, P = 0.05). A 10-fold increase in the quantity of cervical HSV DNA was associated with 1.35-fold higher cervical HIV-1-RNA levels (95% CI 1.00-1.81; P = 0.05), and with 1.36-fold greater odds of detection of HIV-1 proviral DNA (95% CI 1.05-1.75; P = 0.02). CONCLUSION: Higher levels of cervical HSV were associated with higher levels of expressed HIV-1 and with the more frequent detection of HIV-1-infected cells in cervical secretions. Prospective studies are needed to explore further the association between non-ulcerative cervical HSV reactivation and HIV-1 shedding. Such a relationship may have important implications for interventions designed to slow the spread of HIV-1.


Assuntos
Infecções por HIV/virologia , HIV-1/isolamento & purificação , Herpes Genital/virologia , Herpesvirus Humano 2/isolamento & purificação , Doenças do Colo do Útero/virologia , Eliminação de Partículas Virais , Adulto , Estudos Transversais , DNA Viral/análise , Feminino , Infecções por HIV/transmissão , Soropositividade para HIV , HIV-1/genética , Herpes Genital/transmissão , Herpesvirus Humano 2/genética , Humanos , RNA Viral/análise , Carga Viral
9.
Clin Infect Dis ; 35(1): 77-81, 2002 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12060878

RESUMO

We evaluated the association between the severity of primary human immunodeficiency virus type 1 (HIV-1) illness and HIV-1 plasma virus load before seroconversion using stored plasma samples obtained from 74 prostitutes in Mombasa, Kenya. Fever, vomiting, headache, fatigue, arthralgia, myalgia, sore throat, skin rash, or being too sick to work were each associated with significantly higher virus loads before HIV-1 seroconversion, and each additional symptom or sign was associated with an increase in virus load of 0.4 log(10) copies/mL.


Assuntos
Infecções por HIV/fisiopatologia , HIV-1/fisiologia , Índice de Gravidade de Doença , Carga Viral , Feminino , Seguimentos , Infecções por HIV/virologia , Humanos , Quênia/epidemiologia , Estudos Prospectivos , Fatores de Risco , Trabalho Sexual , Saúde da Mulher
10.
Am J Clin Nutr ; 79(2): 218-25, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14749226

RESUMO

BACKGROUND: Serum retinol is the most commonly used indicator of vitamin A status. Retinol is transported in a 1-to-1 complex with retinol-binding protein (RBP). RBP is easy and inexpensive to measure, and studies have shown a high correlation between concentrations of RBP and concentrations of retinol. The performance of RBP in the context of infection or protein malnutrition, however, has not been evaluated. OBJECTIVE: Our aim was to determine whether RBP is a good surrogate measure for retinol in the context of HIV-1 infection, protein malnutrition, and the acute phase response. DESIGN: The relation between RBP and retinol was examined in a cross-sectional study of 600 Kenyan women. RESULTS: There was a high correlation between concentrations of RBP and those of retinol (r = 0.88). When equimolar cutoffs were used, RBP predicted marginal vitamin A status (retinol < 1.05 micro mol/L) with 93% sensitivity and 75% specificity and vitamin A deficiency (retinol < 0.70 micro mol/L) with 91% sensitivity and 94% specificity. Similarly high sensitivities and specificities were found among subgroups with HIV-1 infection, a positive acute phase response, and protein malnutrition. Protein malnutrition and a positive acute phase response were common, especially among HIV-1-infected women, and were independently and synergistically associated with lower RBP concentrations. CONCLUSIONS: Equimolar RBP cutoffs predict vitamin A deficiency with high sensitivity and specificity, even in the context of infection and protein malnutrition. Like retinol, RBP may not accurately identify true vitamin A status under all conditions, because the acute phase response and protein malnutrition depress RBP concentrations. However, RBP may be a simple, inexpensive tool for assessment of vitamin A deficiency in population studies.


Assuntos
Reação de Fase Aguda/etiologia , Infecções por HIV/sangue , Desnutrição Proteico-Calórica/sangue , Proteínas de Ligação ao Retinol/metabolismo , Deficiência de Vitamina A/sangue , Vitamina A/sangue , Adulto , Estudos Transversais , Feminino , Infecções por HIV/complicações , Humanos , Quênia/epidemiologia , Estado Nutricional , Desnutrição Proteico-Calórica/complicações , Deficiência de Vitamina A/epidemiologia , Deficiência de Vitamina A/etiologia
11.
J Clin Virol ; 30(2): 137-44, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15125869

RESUMO

BACKGROUND: Human herpesvirus 8 (HHV-8) antibody tests vary in reported sensitivity and specificity, depending on the population tested and the assay. OBJECTIVE: The purpose of this study was to compare the ability to detect seroconversion to HHV-8 in a cohort of HHV-8 seronegative female commercial sex workers in Kenya using three tests: HHV-8 viral lysate-based enzyme-linked immunosorbent assay (ELISA), an immunofluorescence assay for HHV-8 lytic antigens (IFA-lytic) and IFA for latent nuclear antigens (IFA-LANA). STUDY DESIGN: By ELISA, 16 women from a prospective cohort of commercial sex workers were identified as seroconverting to HHV-8. A total of 124 post-enrollment samples from these 16 women as well as the enrollment samples were tested for HHV-8 antibodies by all three assays to monitor seroconversion. RESULTS: Of 16 women with apparent seroconversion by ELISA, 8 had a rise in IFA-lytic titers either concomitant with or prior to the first positive ELISA sample and no initial LANA by IFA. Five of the 16 women were IFA-LANA positive at entry, indicating prior infection with HHV-8. Three women had no evidence of seroconversion by either IFA-lytic or IFA-LANA and two of these three had increased ELISA reactivity concomitant with HIV-1 infection. CONCLUSIONS: Conversion from a negative to a positive ELISA result for HHV-8 antibody indicated seroconversion in only half of the study cohort of 16 women when IFA-lytic and IFA-LANA results were considered. The IFA-lytic assay was more sensitive than ELISA for early antibody responses. The IFA-LANA was positive in some women who had neither IFA-lytic nor ELISA antibodies suggesting it may be a marker for latent infections. Presumptive identification of incident HHV-8 infection by ELISA screening followed by IFA-lytic testing to confirm the positive test and IFA-LANA to rule out prior infection provides the most accurate documentation of HHV-8 seroconversion.


Assuntos
Anticorpos Antivirais/sangue , Herpesvirus Humano 8/isolamento & purificação , Sarcoma de Kaposi/diagnóstico , Antígenos Virais/análise , Linhagem Celular , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Imunofluorescência/métodos , Soropositividade para HIV/imunologia , Soropositividade para HIV/virologia , Humanos , Quênia , Reprodutibilidade dos Testes , Sarcoma de Kaposi/sangue , Sarcoma de Kaposi/imunologia
13.
J Acquir Immune Defic Syndr ; 47(5): 529-34, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18209681

RESUMO

Levels of HIV-1 RNA in endocervical specimens fluctuate with the menstrual cycle, suggesting that cell-free HIV-1 levels may vary during the cycle, which could influence infectivity. Here, we examined daily changes in endocervical HIV-1-infected cells during 1 cycle. There were significant positive associations between the number of days from the luteinizing hormone surge and the number of HIV-1 DNA copies/swab (P = 0.001) and the number of total cells/swab (P < 0.001) in endocervical specimens. These data suggest that sampling of cell-associated endocervical HIV-1 increases after the periovulatory period, which could result in increased exposure to HIV-1-infected cells during sexual contact.


Assuntos
Colo do Útero/metabolismo , DNA Viral/análise , Infecções por HIV/virologia , HIV-1/fisiologia , Hormônio Luteinizante/metabolismo , Ciclo Menstrual/fisiologia , Adulto , Contagem de Linfócito CD4 , Colo do Útero/virologia , Feminino , Humanos , Vagina/virologia , Carga Viral , Viremia/virologia , Eliminação de Partículas Virais
14.
J Infect Dis ; 191(4): 546-53, 2005 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-15655778

RESUMO

BACKGROUND: A lack of male circumcision has been associated with increased risk of human immunodeficiency virus type 1 (HIV-1) acquisition in a number of studies, but questions remain as to whether confounding by behavioral practices explains these results. The objective of the present study was to model per-sex act probabilities of female-to-male HIV-1 transmission (i.e., infectivity) for circumcised and uncircumcised men, by use of detailed accounts of sexual behavior in a population with multiple partnerships. METHODS: Data were collected as part of a prospective cohort study of HIV-1 acquisition among 745 Kenyan truck drivers. Sexual behavior with wives, casual partners, and prostitutes was recorded at quarterly follow-up visits. Published HIV-1 seroprevalence estimates among Kenyan women were used to model HIV-1 per-sex act transmission probabilities. RESULTS: The overall probability of HIV-1 acquisition per sex act was 0.0063 (95% confidence interval, 0.0035-0.0091). Female-to-male infectivity was significantly higher for uncircumcised men than for circumcised men (0.0128 vs. 0.0051; P=.04). The effect of circumcision was robust in subgroup analyses and across a wide range of HIV-1 prevalence estimates for sex partners. CONCLUSIONS: After accounting for sexual behavior, we found that uncircumcised men were at a >2-fold increased risk of acquiring HIV-1 per sex act, compared with circumcised men. Moreover, female-to-male infectivity of HIV-1 in the context of multiple partnerships may be considerably higher than that estimated from studies of HIV-1-serodiscordant couples. These results may explain the rapid spread of the HIV-1 epidemic in settings, found throughout much of Africa, in which multiple partnerships and a lack of male circumcision are common.


Assuntos
Circuncisão Masculina , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Comportamento Sexual , Adulto , Infecções por HIV/virologia , Humanos , Quênia/epidemiologia , Masculino , Estudos Prospectivos , Fatores de Risco
15.
Epidemiology ; 15(2): 157-63, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15127907

RESUMO

BACKGROUND: Most studies that have found an association between uncircumcised status and infection with human immunodeficiency virus type 1 (HIV-1) have compared participants from various demographic backgrounds, among which the prevalence of other risk factors might have varied. We report findings from a study conducted among men within a single ethnic community in which circumcision was dictated by the religious denomination to which the men belonged. METHODS: Of the 1217 eligible men, we included in the analysis 845 who gave blood samples for HIV-1 testing and who were confirmed as either fully circumcised (n = 398) or uncircumcised (n = 447). The seroprevalence of HIV-1 was compared between the 2 groups. RESULTS: All correlates of HIV-1 prevalence that we measured were distributed similarly between circumcised and uncircumcised men. The seroprevalence of HIV-1 was 30% among the uncircumcised men and 20% among the circumcised men. Among uncircumcised men, HIV-1 seroprevalence was similar between men from circumcising denominations (31%; n = 111) and noncircumcising denominations (30%; n = 336). The crude prevalence ratio for HIV infection associated with not being circumcised was 1.5 (95% confidence interval = 1.2-2.0); and adjustment for other measured risk factors for HIV-1 infection had little impact on this result. CONCLUSION: Our study provides evidence that circumcision is associated with a reduced risk of HIV-1 infection.


Assuntos
Circuncisão Masculina , Soroprevalência de HIV , HIV-1 , Comportamento Sexual , Adulto , Estudos Transversais , Coleta de Dados , Ensaio de Imunoadsorção Enzimática , Humanos , Quênia/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Saúde da População Rural
16.
J Infect Dis ; 189(12): 2192-201, 2004 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15181566

RESUMO

The association between hormone fluctuations during the menstrual cycle and human immunodeficiency virus type 1 (HIV-1) RNA shedding in cervical and vaginal secretions was examined daily for 17 HIV-1-seropositive women, for the duration of 1 cycle. Serum levels of RNA were evaluated 3 times/week. A marginally significant positive correlation between serum levels of progesterone and serum levels of HIV-1 RNA (P=.04) was observed. Cervical virus levels were significantly correlated with the number of days from the midcycle surge in luteinizing hormone (LH) (P=.008). The lowest levels of cervical HIV-1 RNA were present at the LH surge, and this nadir was followed by an increase in virus levels that reached a maximum before the start of menses. In contrast, there was no significant association between the number of days from the LH surge and the level of HIV-1 RNA in vaginal secretions (P=.4). These data support the hypothesis that the level of HIV-1 RNA in cervical secretions is influenced by the menstrual cycle, and they suggest that the risk of heterosexual transmission of HIV-1 may increase as menses is approached.


Assuntos
Colo do Útero/virologia , Infecções por HIV/virologia , HIV-1/fisiologia , Menstruação , RNA Viral/análise , Eliminação de Partículas Virais , Feminino , Humanos , Progesterona/sangue , RNA Viral/sangue , Vagina/virologia
17.
J Infect Dis ; 190(10): 1880-8, 2004 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-15499546

RESUMO

Understanding how the level of human immunodeficiency virus type 1 (HIV-1)-infected breast milk cells (BMCs) affects HIV transmission via breast-feeding can shed light on the mechanism of infection and aid in establishing effective interventions. The proportion of infected cells to total cells was measured in serial breast milk samples collected from 291 HIV-1-infected women in Nairobi, Kenya, by use of real-time DNA polymerase chain reaction amplification of BMCs. The number of infected BMCs per million cells was associated with levels of cell-free viral RNA in breast milk (R=.144; P=.032), levels of cell-free virus in blood plasma (R=.365; P<.001), and the detection of proviral DNA in cervical and vaginal secretions (P<.001 and P = .030, respectively). The number of infected BMCs per million cells was lower in colostrum or early milk than in mature milk (P<.001). Previous studies demonstrated that the concentration of BMCs varies throughout lactation, and we used these data to transform infected BMCs per million cells to infected BMCs per milliliter. The estimated concentration of infected BMCs per milliliter was higher in colostrum or early milk than in mature milk (P<.001). Each log10 increase in infected BMCs per milliliter was associated with a 3.19-fold-increased risk of transmission (P=.002), after adjustment for cell-free virus in plasma (hazard ratio [HR], 2.09; P=.03) and breast milk (HR, 1.01; P=1.00). This suggests that infected BMCs may play a more important role in transmission of HIV via breast-feeding than does cell-free virus.


Assuntos
Aleitamento Materno , Infecções por HIV/transmissão , HIV-1/fisiologia , Transmissão Vertical de Doenças Infecciosas , Leite Humano/citologia , Leite Humano/virologia , Sangue/virologia , Colo do Útero/virologia , Colostro/citologia , Colostro/virologia , DNA Viral/análise , Feminino , HIV-1/isolamento & purificação , Humanos , Quênia , Reação em Cadeia da Polimerase , Provírus/isolamento & purificação , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vagina/virologia
18.
J Infect Dis ; 187(5): 736-40, 2003 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-12599046

RESUMO

Human immunodeficiency virus type 1 (HIV-1) is transmitted through blood, genital secretions, and breast milk. The probability of heterosexual transmission of HIV-1 per sex act is.0003-.0015, but little is known regarding the risk of transmission per breast-milk exposure. We evaluated the probability of breast-milk transmission of HIV-1 per liter of breast milk ingested and per day of breast-feeding in a study of children born to HIV-1-infected mothers. The probability of breast-milk transmission of HIV-1 was.00064 per liter ingested and.00028 per day of breast-feeding. Breast-milk infectivity was significantly higher for mothers with more-advanced disease, as measured by prenatal HIV-1 RNA plasma levels and CD4 cell counts. The probability of HIV-1 infection per liter of breast milk ingested by an infant is similar in magnitude to the probability of heterosexual transmission of HIV-1 per unprotected sex act in adults.


Assuntos
Aleitamento Materno , Infecções por HIV/transmissão , HIV-1 , Transmissão Vertical de Doenças Infecciosas , Leite Humano/virologia , Adulto , Contagem de Linfócito CD4 , Criança , Feminino , Infecções por HIV/virologia , Humanos , Lactente , Alimentos Infantis , Recém-Nascido , Mães , Probabilidade , RNA Viral/sangue , Carga Viral
19.
J Infect Dis ; 187(5): 741-7, 2003 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-12599047

RESUMO

Transmission of human immunodeficiency virus type 1 (HIV-1) via breast-feeding can occur throughout lactation. Defining both fluctuation in breast-milk virus level over time and how breast-milk virus correlates with mother-to-child transmission is important for establishing effective interventions. We quantified breast-milk HIV-1 RNA levels in serial samples collected from 275 women for up to 2 years after delivery. Higher maternal plasma virus load, lower maternal CD4 T cell count, and detection of HIV-1 DNA in maternal genital secretions were significantly associated with elevated breast-milk HIV-1 RNA. Within women who breast-fed, median virus load in colostrum/early milk was significantly higher than that in mature breast milk collected 14 days after delivery (P< or =.004). Breast-feeding mothers who transmitted HIV-1 to their infants had both significantly higher breast-milk viral RNA throughout lactation and more-consistent viral shedding, compared with mothers who did not transmit HIV-1. In breast-feeding women, a 2-fold-increased risk of transmission was associated with every 10-fold increase in breast-milk virus load (95% confidence interval, 1.3-3.0; P<.001). These results indicate that the risk of infant infection from breast-feeding is influenced by breast-milk virus load, which is highest early after delivery.


Assuntos
Aleitamento Materno , Infecções por HIV/transmissão , HIV-1/fisiologia , Transmissão Vertical de Doenças Infecciosas , Leite Humano/virologia , RNA Viral/análise , Pré-Escolar , DNA Viral/análise , Feminino , Infecções por HIV/virologia , HIV-1/genética , Humanos , Lactente , Alimentos Infantis , Recém-Nascido , Estudos Longitudinais , Gravidez , RNA Viral/sangue , Carga Viral , Eliminação de Partículas Virais
20.
J Infect Dis ; 187(3): 359-63, 2003 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-12552419

RESUMO

Human herpesvirus 8 (HHV-8) infection is very prevalent in sub-Saharan Africa, but the role of sexual transmission has not been well characterized. HHV-8 seroprevalence and correlates were evaluated in a cohort of female prostitutes in Mombasa, Kenya. Between February 1993 and January 2000, stored plasma samples taken from 736 women were tested, by whole-virus ELISA assay, for the presence of HHV-8 antibodies; of these 736 women, 633 were included in the analysis of correlates of HHV-8 infection; and, of these 633, 44.1% were seropositive for HHV-8 antibodies. In univariate analysis, age, years of education, years of prostitution, workplace, hormonal contraception, intrauterine-device use, alcohol consumption, syphilis, and gonorrhea were all significantly associated with the presence of HHV-8 antibodies. In a multivariate model, older age, fewer years of education, and 2 markers of high-risk sexual behavior-namely, alcohol consumption and gonorrhea-were each independently associated with HHV-8 seropositivity. These results suggest that heterosexual transmission may contribute to acquisition of HHV-8 infections in this African population of prostitutes.


Assuntos
Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/virologia , Herpesvirus Humano 8/isolamento & purificação , Trabalho Sexual , Doenças Virais Sexualmente Transmissíveis/epidemiologia , Doenças Virais Sexualmente Transmissíveis/virologia , Adulto , Fatores Etários , Consumo de Bebidas Alcoólicas , Anticorpos Antivirais/isolamento & purificação , Preservativos/estatística & dados numéricos , Anticoncepcionais , Escolaridade , Feminino , Herpesvirus Humano 8/imunologia , Humanos , Quênia/epidemiologia , Fatores de Risco , Estudos Soroepidemiológicos
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