Lower mother-to-child HIV-1 transmission in boys is independent of type of delivery and antiretroviral prophylaxis: the Italian Register for HIV Infection in Children

The relationship between infant's gender and rate of HIV-1 mother-to-child transmission (MTCT) was evaluated in a prospective cohort of 4151 children (2166 boys and 1985 girls) born to HIV-1-infected mothers enrolled in the Italian Register for HIV Infection in Children. Logistic regression models were performed to estimate crude odds ratios (ORs) and adjusted odds ratios (AORs) and 95% CIs for factors potentially influencing MTCT separately for the period 1985-1995 and the period 1996-2001. To evaluate rates of MTCT by gender in specific subgroups, separate logistic regression models by mode of delivery and antiretroviral prophylaxis were performed. Among children born in 1985-1995, 15.5% boys (95% CI: 13.6-17.7) and 17.9% girls (95% CI: 15.7-20.3) were infected (P = 0.1181). After 1995, a lower proportion of boys (3.1% [95% CI: 2.0-4.4]; AOR: 0.43 [95% CI: 0.26-0.71], P = 0.0008) than girls (AOR: 6.3%, 95% CI: 4.8-8.1) was infected. Lower AORs for boys persisted independently of elective cesarean delivery (AOR: 0.31, 95% CI: 0.14-0.71); other than elective cesarean (AOR: 0.38, 95% CI: 0.19-0.78) and antiretroviral prophylaxis (zidovudine monotherapy (AOR: 0.11, 95% CI: 0.03-0.38); none (AOR: 0.43, 95% CI: 0.21-0.90). No difference was observed when combined therapy in the mother was administered (AOR: 1.14, 95% CI: 0.30-4.32), but results were likely to be biased by the very low rate of infected children in this group. A lower proportion of HIV-1-infected boys in children born after 1995 was found. Factor(s) intrinsic to gender (rather than type of delivery or maternal antiretroviral prophylaxis) may be involved, because the risk of infection in boys was lower independent of interventions. A possible explanation is that, among infected fetuses, more girls survive up to the end of pregnancy and may take advantage of the benefits of preventive strategies.     

Placental membrane inflammation and risks of maternal-to-child transmission of HIV-1 in Uganda

Prospective follow-up of 172 HIV-infected pregnant women and their infants was conducted at Mulago Hospital, Kampala, Uganda during 1990 to 1992. Information was collected on maternal immune status (CD4 counts or clinical AIDS), and concurrent infections with sexually transmitted diseases. Infants were observed on a follow-up basis to determine HIV infection, using polymerase chain reaction (PCR) under 15 months of age and enzyme immunoassay/Western blot for those older than 15 months. Placental membrane inflammation (chorioamnionitis and funisitis), and placental villous inflammation (villitis, intervillitis, and deciduitis) were diagnosed by histopathology. Mother-to-child HIV transmission rates were assessed, and adjusted odds ratios (OR) and 95% confidence intervals (95% CI) of transmission were estimated using women with no placental pathology or evidence of immune suppression as a reference group. RESULTS: The overall mother-to-child HIV transmission rate was 23.3%. Women with no placental membrane inflammation or immune suppression had a transmission rate of 11.3%; compared with 25.5% in women with placental inflammation and no immunosuppression (adjusted OR, 2.87; 95% CI, 1.04-7.90), and 37.0% in immunosuppressed women (OR, 3.07; 95% CI, 1.42-6.67). We estimate that 34% of HIV transmission could be prevented by treatment of placental membrane inflammation in nonimmunocompromised women. Transmission rates were 40.9% with genital ulcer disease (OR, 3.57; 95% CI, 1.28-9.66). Placental villous inflammation and artificial rupture of membranes did not increase transmission rates and cesarean section was associated with a nonsignificant reduction of risk (OR, 0.70; 95% CI 0.24-2.06). CONCLUSION: Placental membrane inflammation increases the rate of mother-to-child HIV transmission.     

Effect of maternal HIV and malaria infection on pregnancy and perinatal outcome in Zimbabwe

OBJECTIVE: To investigate the effect of isolated or concomitant infection with malaria and HIV on pregnancy and neonatal outcome. METHODS: Data were collected on pregnant women admitted during the rainy seasons in the obstetric division of a district referral hospital in northern Zimbabwe in 2000 and 2001. The effects of malaria and HIV infection were determined by multivariate analysis. RESULTS: The prevalence of HIV seropositivity and symptomatic malaria in 986 pregnant women was 8.3% and 14.7%, respectively. HIV-infected women were more likely to develop malaria attacks during pregnancy than seronegative women (odds ratio [OR] = 3.96, 95% confidence interval (CI): 2.42-6.46). Malaria and HIV infections were associated with increased risk of stillbirth (OR = 4.74, 95% CI: 1.34-16.78) and preterm delivery (OR = 4.10, 95% CI: 2.17-7.75), respectively. They were independently associated with increased risk of low birth weight (malaria: OR = 10.09, 95% CI: 6.50-15.65; HIV: OR = 3.16, 95% CI: 1.80-5.54) and very low birth weight (malaria: OR = 5.04, 95% CI: 1.00-25.43; HIV: OR = 10.74, 95% CI: 2.12-54.41), low Apgar score (malaria: OR = 4.45, 95% CI: 1.42-13.94; HIV: OR = 5.94, 95% CI: 1.66-21.30), and fetal growth restriction (malaria: OR = 3.98, 95% CI: 2.51-6.30; HIV: OR = 4.07, 95% CI: 2.40-6.92). Dual infection with malaria and HIV was associated with increased risk of maternal, perinatal, and early infant death. CONCLUSIONS: Women with single HIV or malaria infection have a significantly increased risk of adverse outcomes of pregnancy and childbirth. Dual infection has additional detrimental effects on maternal and infant survival in an area where HIV and malaria coexist.     

Addition of single-dose tenofovir and emtricitabine to intrapartum nevirapine to reduce perinatal HIV transmission

OBJECTIVE: To determine the impact of adjuvant single-dose peripartum tenofovir/emtricitabine (TDF/FTC) on intrapartum/early postpartum HIV transmission. METHODS: In the setting of routine short-course zidovudine (ZDV) and peripartum nevirapine (NVP) for perinatal HIV prevention, participants were randomized to single-dose TDF (300 mg)/FTC (200 mg) or to no intervention in labor. Six-week infant HIV infection was compared according to actual-use drug regimens. RESULTS: Of 397 women randomized, 355 (89%) had infants who were alive and active at 6 weeks postpartum. Of these, 18 (5.1%) were infected in utero and 6 (1.8%) were infected intrapartum/early postpartum. Among the 243 who used ZDV and NVP, intrapartum/early postpartum transmission was not reduced among infants whose mothers received TDF/FTC compared with those who did not (2 of 123 [1.6%] vs. 3 of 109 [2.8%]; P = 0.67). Among the 49 infants whose mothers did not receive antenatal ZDV but who had confirmed NVP ingestion, transmission similarly did not differ (0 of 19 [0%] vs. 1 of 26 [3.4%]). TDF/FTC was not significantly associated with reduced overall transmission (odds ratio [OR] = 0.7, 95% confidence interval [CI]: 0.3 to 1.6), even when other antiretroviral drugs were considered (adjusted OR = 0.8, 95% CI: 0.3 to 1.8). CONCLUSIONS: Adjuvant peripartum single-dose TDF/FTC did not reduce perinatal transmission. Whether a higher dose might be effective remains unknown but should be studied in settings in which NVP is used without antenatal ZDV.     

Vertical transmission of HIV in Ghanaian women diagnosed in cord blood and post-natal samples

HIV RNA detection in the newborn is the main diagnostic tool for vertical transmission. Most infections are thought to occur peri- or post-natally, hence preventive antiviral therapy administered days before and during delivery. This study used cord blood for molecular diagnosis, examined viral load and HIV-1 subtypes as determinants of transmission, and compared molecular variability of maternal, cord blood, and post-natal quasispecies. Ninety-seven seropositive mother-cord blood paired plasmas from Ghana were tested for HIV RNA. Viral load was quantified and a subgroup of 45 random women samples was typed and subtyped. HIV-1 from infected pairs was cloned, sequenced, and analyzed phylogenetically. The prevalence of HIV infection in pregnant women was 3.3%. 13/97 cord blood samples (13.5%) contained HIV RNA. No correlation between either viral load at labor (range 10(3)-10(7)) or HIV-1 subtype and in utero transmission was found. In both transmitting and non-transmitting mothers, 56% of HIV-1 strains were CRF02_AG. In three pairs, maternal and cord blood quasispecies were closely related, suggesting late pregnancy or perinatal transmission, while in four pairs, genetic distances suggested transmission earlier during gestation. Maternal viral load and genotype did not correlate with HIV-1 pre-natal transmission. HIV infection during gestation appears relatively frequent.     

Reduced mortality associated with breast-feeding-acquired HIV infection and breast-feeding among HIV-infected children in Zambia

OBJECTIVES: In developing countries, where mother-to-child transmission of HIV through breast-feeding is common, little is known about the impact of postpartum transmission on child survival. This study assessed whether children infected postpartum have longer survival from time of infection versus those infected during gestation or delivery. DESIGN: We used a prospective cohort study to analyze data from 213 HIV-infected children enrolled in a breast-feeding intervention trial in Lusaka, Zambia (2001 to 2004). METHODS: We compared mortality 1 year after HIV infection in children stratified by age of infection: 0 to 3 days (intrauterine [IU] group), 4 to 40 days (intrapartum/early postpartum [IP/EPP] group), and >40 days (postpartum [PP] group). RESULTS: A total of 61, 71, and 81 children were infected in the IU, IP/EPP, and PP groups, respectively. Children with intrauterine or intrapartum/early postpartum transmission had higher mortality over the first 12 months after infection than children with postpartum transmission (P = 0.001 and P = 0.006, respectively); no differences were detected between children with intrauterine and intrapartum/early postpartum transmission. Nearly 20% of the IU and IP/EPP groups died by 100 days after infection, whereas nearly 10% of the PP group had died by this time. After adjusting for birth weight, maternal CD4 cell count, breast-feeding, and maternal death, children infected postpartum had one quarter the mortality rate (hazard ratio [HR] = 0.27, 95% confidence interval [CI]: 0.15 to 0.50) of those infected in utero. Stopping breast-feeding increased mortality in infected children (HR = 3.1, 95% CI: 1.8 to 5.3). CONCLUSIONS: This study demonstrates a survival benefit among children infected postpartum versus children infected during pregnancy or delivery and a benefit to increased breast-feeding duration among infected children. Testing children for HIV early may provide a means to allow for earlier intervention.     

High prevalence of syphilis,HBV, and HCV co‐infection,and low rate of effective vaccination against hepatitis B in HIV‐infected patients in West China hospital

To investigate the epidemiological features and risk factors of HBV, HCV, and syphilis infection among HIV‐infected patients in West China Hospital. A retrospective study was conducted with HIV‐infected patients from 2014 to 2016 in West China hospital, SCU. Serum makers for HBV, HCV, and syphilis were detected. Among 894 HIV‐infected patients, the prevalence of HIV/HBV, HIV/HCV, HIV/syphilis co‐infections was 14.4%, 5.7%, and 18.9% respectively. HIV/HBV/HCV, HIV/HCV/syphilis, and HIV/HBV/syphilis triple co‐infection was 7 (0.7%), 12(1.3%), 29(3.2%) respectively. The rate of effective vaccination against HBV was only 7.7% in HIV‐infected patients. Age (OR = 0.243 95% CI: 0.114 ?0.518), ethnicity (OR = 3.654 95% CI: 1.849‐7.218) and education level (OR = 0.140 95% CI: 0.033‐0.606) are risk factors affecting HIV/HCV co‐infection. A high prevalence of HIV/syphilis, HIV/HBV, and HIV/ HCV co‐infection can be observed in west China. The rate for HIV‐infected patients who were effectively vaccinated against HBV was fewer than 10%.     

Associations of chemokine receptor polymorphisms With HIV-1 mother-to-child transmission in sub-Saharan Africa: possible modulation of genetic effects by antiretrovirals

BACKGROUND: HIV-1 mother-to-child transmission (MTCT) remains an important route of infection in sub-Saharan Africa. METHODS: Genetic variants in CCR5 promoter, CCR2, CX3CR1, and Stromal cell-derived factor-1 (SDF-1) genes were determined in 980 infants from sub-Saharan Africa using real-time polymerase chain reaction to determine association with MTCT. RESULTS: In antiretroviral-naive mother-infant pairs (n = 637), CCR5 promoter polymorphisms at positions 59029: A allele vs. G/G [odds ratio (OR): 1.61, 95% confidence interval (CI): 1.04 to 2.48; P = 0.032] and 59356: T allele vs. C/C (OR: 0.63, 95% CI: 0.41 to 0.96; P = 0.033) and CCR2-180: G allele vs. A/A (OR: 3.32, 95% CI: 1.13 to 9.73; P = 0.029) were associated with risk of MTCT. Treatment of HIV-1-infected mothers and infants with single-dose nevirapine or perinatal zidovudine altered but did not eliminate the association of genetic variants with MTCT. CONCLUSIONS: CCR5 promoter, CCR2, and CX3CR1 polymorphisms were associated with risk of MTCT likely through their role as an HIV-1 coreceptor or by modulating the early immune response. Host genetics may continue to alter MTCT when short-course interventions that only partially suppress virus are used. These findings will need to be confirmed in validation cohorts with a large number of infected infants.     

Couples at risk: HIV-1 concordance and discordance among sexual partners receiving voluntary counseling and testing in Uganda

OBJECTIVE: To determine correlates of HIV-1 concordance for couples receiving voluntary HIV counseling and testing. DESIGN: Cross-sectional study of couples receiving voluntary HIV counseling and testing in Kampala, Uganda. METHODS: An interview and physical examination were conducted for 49 HIV-1-concordant (both partners infected with HIV) and 126 HIV-1-discordant (1 partner infected with HIV and 1 partner HIV negative) couples. Blood samples from all participants were tested for HIV-1 and syphilis serology. CD4 cell count and HIV load were characterized for all HIV-infected persons. Urine samples were tested for Neisseria gonorrhoeae and Chlamydia trachomatis using ligase chain reaction. Associations between couples' HIV status and key sociodemographic, behavioral, and biomedical factors were analyzed. RESULTS: Men in HIV-concordant couples were more likely than men in HIV-discordant couples to be living together with their sexual partner (odds ratio [OR], 11.3; 95% confidence interval [CI], 2.8-53.7; P=0.004), to be uncircumcised (OR, 4.5; 95% CI, 1.1-18.8; P=0.042), and to have higher HIV loads (OR for each log increase, 3.0; 95% CI, 2.0-4.7; P<0.001). Women in HIV-concordant couples were more likely than women in HIV-discordant couples to be living together with their sexual partner (OR, 19.0; 95% CI, 3.8-84.8), to have an uncircumcised male partner (OR, 6.5; 95% CI, 1.6-26.4), to have had a sexually transmitted disease in the 6 months before enrollment (OR, 1.9; 95% CI, 0.9-4.5), and to have higher HIV loads (OR for each log increase, 2.2; 95% CI, 1.5-3.2). CONCLUSIONS: Several behavioral and biologic risk factors were associated with HIV concordance for couples. Providing early sexually transmitted disease diagnosis and treatment, antiretroviral therapy, and specially designed counseling to HIV-discordant couples may help prevent HIV transmission in couples where being in a stable sexual relationship is a major risk factor for HIV infection.     

Caesarean section delivery and the risk of allergic disorders in childhood

BACKGROUND: The composition of the intestinal flora in young children, if unfavourable, may increase the susceptibility to allergic disorders. Beneficial intestinal microbes originate from the maternal vaginal tract and thus are more likely to be transferred during vaginal births than during Caesarean sections (C-sections). OBJECTIVE: To determine whether children born by C-section have a different risk of allergic disorders compared with those delivered vaginally. We also tested the hypothesis that the risk of allergic disorders is highest for children born after 'repeat C-sections'. METHODS: A retrospective cohort study of 8,953 children aged 3-10 years. Children diagnosed with allergic rhinoconjunctivitis (AR), asthma, atopic dermatitis (AD), or food allergies were identified from the Kaiser Permanente Northwest Region electronic records. The children's sex, birth weight, birth order, postnatal exposure to antibiotics as well as the mothers' age, ethnicity, education, marital status, smoking status during pregnancy, and use of asthma or hayfever medications were identified through the mothers' medical records or through the Oregon Birth Registry. RESULTS: The risk of being diagnosed with AR was significantly higher in the children born by C-section than in those delivered vaginally: adjusted odds ratio (OR)=1.37%, 95% confidence interval (CI)=1.14-1.63. Delivery by C-section was also associated with the subsequent diagnosis of asthma (OR=1.24%, 95% CI=1.01-1.53); this association was gender specific, with a positive association restricted to girls (OR for asthma in girls: OR=1.53%, 95% CI=1.11-2.10; in boys: OR=1.08%, 95% CI=0.81-1.43). There was no significant association between mode of delivery and AD. If children born in a 'repeat C-section' were considered separately the risk of being diagnosed with AR increased further (OR=1.78%, 95% CI=1.34-2.37). The same increase was noted for asthma in girls (OR=1.83%, 95% CI=1.13-2.97) but not in boys. CONCLUSION: Caesarean sections may be associated with an increased risk of developing AR in childhood.     

Delayed onset of pubertal development in children and adolescents with perinatally acquired HIV infection

OBJECTIVE: To examine whether greater severity of HIV infection is associated with delayed initiation of pubertal development among perinatally HIV-infected children, and to compare sexual maturation of perinatally HIV-infected children with children in the general US population using the National Health and Nutrition Examination Survey III. METHODS: In a prospective cohort study, the authors studied 983 HIV-infected children aged 6 to 18 years, who had Tanner stage assessed on at least two occasions between 1995 and 2000. Analyses were conducted separately for girls and boys to identify factors associated with onset of puberty or adrenarche (progression beyond Tanner stage 1). RESULTS: Among children who were in Tanner stage 1 at their first assessment, 185 of 413 (45%) girls and 144 of 434 (33%) boys entered puberty during the observation period. In multivariate longitudinal regression analyses adjusted for age, race/ethnicity, time interval between study visits, and other clinical factors, girls with severe immunosuppression (CD4% <15) were significantly less likely to enter adrenarche (odds ratio [OR], 0.48; 95% confidence interval [CI], 0.29-0.83) and puberty (OR, 0.57; 95% CI, 0.33-0.96) compared with girls who were not immunosuppressed (CD4% > or =25). For boys, those with severe immunosuppression were significantly less likely to enter adrenarche (OR, 0.52; 95% CI, 0.28-0.96) and tended to be less likely to begin puberty (OR, 0.69; 95% CI, 0.39-1.22) compared with boys who were not immunosuppressed. Qualitative comparisons suggested that HIV-infected children may experience delayed puberty and adrenarche compared with similarly aged children in the general US population. CONCLUSIONS: Immunosuppression was associated with delayed pubertal onset in perinatally HIV-infected children. Further studies of perinatally HIV-infected and uninfected children are needed to better quantify the delay in pubertal onset and to compare the pace of pubertal maturation.     

Safety of antiretroviral prophylaxis of perinatal transmission for HIV-infected pregnant women and their infants

Worldwide, more than 1600 infants become infected with HIV each day. Almost all infections are a result of mother-to-child transmission of HIV, with most of these infections occurring in resource-poor countries. In developed countries, antiretroviral prophylaxis has dramatically reduced perinatal transmission to <2%. The potential now exists to extend this success to resource-poor countries using effective but shorter and less expensive antiretroviral regimens.With the potential widespread use of antiretroviral therapy for perinatal HIV prevention in resource-limited settings, there will be exposure of increasing numbers of infants to in utero and postpartum antiretroviral drugs for which long-term toxicity data is unknown. This article focuses on a review of what is known about safety of antiretroviral regimens used to interrupt mother-to-child transmission for women and their children.     

HIV prevalence and predictors among rescued sex-trafficked women and girls in Mumbai, India

OBJECTIVE: Despite the rapid spread of India's HIV epidemic through commercial sex and the large numbers of minor girls trafficked to India for sex work each year, little HIV research has been conducted among victims of sex trafficking. The present study examines the prevalence and predictors of HIV infection among sex-trafficked women and girls rescued from brothels in Mumbai, India. DESIGN AND METHODS: Case records and HIV testing results of sex-trafficked women and girls (N = 175) were reviewed. HIV prevalence and HIV risk were assessed based on demographics and exposure to sex work. RESULTS: Approximately one quarter (22.9%) of trafficked individuals tested positive for HIV. The mean age at trafficking was marginally younger for women and girls infected with HIV (15.9 years) as compared to those not infected (17.2 years; P = 0.06). Girls trafficked as minors reported longer periods of brothel confinement as compared to those trafficked at older ages (18.5 vs. 9.6 months; P = 0.007). Among Indian victims, those trafficked from the states of Karnataka or Maharashtra were more likely than those trafficked from West Bengal to be HIV-positive (odds ratio [OR] = 7.35, 95% confidence interval [CI]: 2.23 to 24.21). Longer duration in brothels was associated with greater likelihood of HIV infection; a 3% to 4% increased risk for HIV was observed for each additional month of brothel captivity. CONCLUSIONS: Findings demonstrate the need for increased attention to HIV among young victims of sex trafficking in research and practice, and to the rescue of sex trafficking victims as a form of HIV prevention.     

Risk factors for neonatal infections in full-term babies in South Korea

PURPOSE: Since 1997, private postnatal care facilities (San-hu-jo-ri-won in Korean) have emerged to take the role of the family. As a result, neonates are now exposed to many people and are very vulnerable to infection. However, there has been no study on the influence of postnatal care facilities on neonatal infection. The aim of this study was to determine the risk factors of neonatal infection in full-term babies in Korea. MATERIALS AND METHODS: We followed up 556 pregnant women and their babies for 4 weeks after their births at 2 hospitals in Seoul and Daejeon from October 2004 to September 2005. Among 512 full-term babies, 58 had infectious diseases. To determine the risk factors for infection, 53 infected neonates at 4-28 days of life and 413 healthy neonates were compared. RESULTS: The incidence of neonatal infection at 4 to 28 days after birth was 10.5%. After adjusting the related factors, the number of siblings (OR = 2.05, 95% CI = 1.13-3.71 for 1 or more) and postnatal care facilities or home aides (OR = 1.91, 95% CI = 1.07-3.45) were significant risk factors. Formula or mixed feeding (OR = 1.66, 95% CI = 0.91-3.04) increased the risk of neonatal infection but it was not statistically significant. CONCLUSION: When the newborns had siblings, stayed at postnatal care facilities, or were cared for by home aides, the risk of neonatal infections significantly increased. Further research on the feeding effect on neonatal infection and evaluation of prevention efforts are needed.     

Prevalence of human herpesvirus 8 and hepatitis C virus in a rural community with a high risk for blood-borne infections in central China

Illegal blood donation in the past decade has caused human immunodeficiency virus (HIV) outbreaks in some rural areas in China. Other HIV-associated virus infections, such as those caused by human herpesvirus 8 (HHV8), in such areas are still not well defined. In order to explore HHV8 and hepatitis C virus (HCV) seroprevalence and potential risk factors in such areas, a cross-sectional study with 305 HIV-positive and 315 HIV-negative subjects recruited from a rural county in Shanxi province was conducted, in which illegal blood collection was reported. Interview questionnaires and serum testing were carried out with these participants. HCV and HHV8 seroprevalence were found to be higher in the HIV-positive than in the HIV-negative group (76.4% vs. 2.5% and 15.4% vs. 4.8%, respectively), whereas the difference in HBV seroprevalence was not significant. Co-infection with HCV and HHV8 was also more prevalent in the HIV-positive group. HIV status (OR 2.71; 95% CI 1.16–6.30) and HBV status (OR 2.56; 95% CI 1.14–5.75) were independently associated with HHV8 infection. HIV status (OR 23.03; 95% CI 9.95–53.27) and blood/plasma selling history (OR 14.57; 95% CI 7.49–28.23) were strongly associated with HCV infection. These findings demonstrate that both HHV8 and HCV infections are prevalent in this community. HIV infection is an important risk factor for both HHV8 and HCV infection. HBV infection is associated with HHV8 infection but not with HCV infection. It is possible that HHV8 and hepatitis B virus, but not HCV, have similar modes of transmission in this population.     

HIV-1 viral load and other risk factors for mother-to-child transmission of HIV-1 in a breast-feeding population in Cote d'Ivoire

Short-course antiretroviral regimens have been evaluated to reduce mother-to-child transmission of HIV in resource-limited settings. This report from Abidjan, Cote d'Ivoire, examines the risk factors for HIV transmission by 1 and 24 months among breast-feeding women. Eligible HIV-1-seropositive pregnant women enrolled in this randomized double-blind clinical trial were randomly assigned to receive either oral zidovudine (ZDV) (n = 126) prophylaxis or placebo (n = 124). Maternal prophylaxis began at 36 weeks of gestation (300 mg ZDV twice daily antepartum and 300 mg every 3 hours intrapartum); there was no neonatal prophylaxis component. The cumulative risk of transmission in the treatment group was 11.9% and 22.1% by 1 and 24 months, respectively. In adjusted analyses, viral load at enrollment was the strongest predictor of transmission (per log increment: odds ratio [OR] = 4.8, 95% confidence interval [CI]: 2.5-9.5 at 1 month; OR = 5.7; 95% CI: 3.1-10.8 at 24 months). Overall, ZDV prophylaxis was not significantly protective for infection at 1 or 24 months. Comparing ZDV with placebo following dichotomization of viral load (<50,000 vs. > or =50,000 copies/mL) at enrollment, however, there was a significant effect of ZDV seen only among those women with a low viral load at enrollment. The substantial risk of transmission despite ZDV prophylaxis, particularly among those with higher viral loads, underscores the need to find more effective regimens appropriate for use in resource-limited settings.     

Risk factors for incident HIV infection among anonymous HIV testing site clients in Santos,Brazil: 1996-1999

OBJECTIVES: To determine temporal trends in HIV infection and risk factors among persons seeking anonymous HIV testing in Santos, Brazil. METHODS: Data and sera from persons testing for HIV from 1996 to 1999 were used. Exposures were abstracted from HIV testing risk assessments. Stored HIV-positive sera were tested to identify recently acquired HIV infection using a serologic testing algorithm for detecting recent HIV seroconversion (STARHS). Independent associations between exposures and recently acquired HIV infection were determined using multivariate analyses. RESULTS: Overall, estimated HIV incidence was 2.0% (95% CI: 1.1-3.5) for the 4-year period: 1.2% (95% CI: 0.5-2.6) in women and 2.7% (95% CI: 1.3-5.0) in men. Incidence increased among women but remained stable among men. Exposures independently associated with incident infection included a history of sex work (OR= 5.4, 95% CI: 1.5-18.7), concurrent syphilis infection (OR =4.1, 95% CI: 1.4-11.9), anal sex (OR = 3.0, 95% CI: 1.3-7.1), and having an HIV-positive sexual partner (OR= 1.4, 95% CI: 1.1-1.9). CONCLUSIONS: This study further demonstrates the public health utility of using the STARHS for the assessment of emerging trends in the HIV epidemic. Results from this study will help to target appropriate prevention strategies directed toward at-risk populations in Santos.     

Risk factors for in utero and intrapartum transmission of HIV

OBJECTIVE: To identify predictors of in utero and intrapartum HIV-1 transmission in infants born in the Women and Infants Transmission Study between 1990 and 2000. METHODS: In utero HIV-1 infection was defined as an infant with the first positive HIV-1 peripheral blood mononuclear cell culture and/or DNA polymerase chain reaction assay at 7 days of age or younger; intrapartum infection was defined as having a negative HIV-1 culture and/or DNA polymerase chain reaction assay at 7 days of age or younger and the first positive assay after 7 days of age. RESULTS: Of 1709 first-born singleton children with defined HIV-1 infection status, 166 (9.7%) were found to be HIV-1 infected; transmission decreased from 18.1% in 1990-1992 to 1.6% in 1999-2000. Presumed in utero infection was observed in 34% of infected children, and presumed intrapartum infection, in 66%. Among infected children, the proportion with in utero infection increased over time from 27% in 1990-1992 to 80% (4 of 5) in 1999-2000 (P = 0.072). Maternal antenatal viral load and antiretroviral therapy were associated with risk of both in utero and intrapartum transmission. Controlling for maternal antenatal viral load and antiretroviral therapy, low birth weight was significantly associated with in utero transmission, while age, antenatal CD4 cell percentage, year, birth weight, and duration of membrane rupture were associated with intrapartum transmission. CONCLUSION: Although there have been significant declines in perinatal HIV-1 infection over time, there has been an increase in the proportion of infections transmitted in utero.     

Intrafamilial transmission of hepatitis C virus: infection of the father predicts the risk of perinatal transmission

The aims of the present study were to evaluate in a cohort of mothers infected with hepatitis C virus (HCV) the prevalence of HCV infection of their sexual partners, the influence of infection of the partners on perinatal transmission, and whether this influence is mediated by other well known risk factors for perinatal transmission. Forty-nine consecutive mothers infected with HCV who transmitted infection to their offspring and, as a control group, 557 consecutive mothers infected with HCV who did not transmit infection, together with their children and the fathers of the children who were also the sexual partners of the mothers were evaluated. History of intravenous drug use was significantly more frequent in women with partners infected with HCV than in women with partners not infected [115/180 (63.9%) vs. 87/401 (21.7%); relative risk (RR): 6.38, 95% confidence intervals (CI): 4.34-9.39, P < 10(-3)]. HCV infection was more frequent in the partners of mothers who transmitted perinatally HCV [23/49 (46.9%) vs. 174/557 (31.2%); RR: 1.95, 95%CI: 1.08-3.51, P = 0.03]. Multivariate analysis demonstrated that paternal HCV infection is not a risk factor per se for perinatal HCV transmission, but its role is dependent on maternal intravenous drug use [adjusted RR: 1.23 (95%CI: 0.44-3.39, P = 0.6)]. In conclusion, the present study shows that partners of mothers infected with HCV with a history of intravenous drug use were at a higher risk of HCV infection. HCV infection of the father seems to be associated with perinatal transmission but this relationship is dependent on maternal history of intravenous drug use.