Prevention of vertical HIV transmission in Campos dos Goytacazes, Rio de Janeiro, Brazil

Prevention of mother-to-child HIV transmission is an emerging public health challenge. In Brazil, preventive prophylaxis with AZT during pregnancy, at delivery, and for newborns was introduced in 1996, with a marked reduction in transmission (less than 5.0% nationwide). Since 1999 the Municipal STD/AIDS Program in Campos dos Goytacazes, Rio de Janeiro State (population = 416,441) has acted in the prevention of vertical transmission. In 2001/2003, there was a moderately increased implementation (from 28.0% to 36.0%) of HIV screening services during pregnancy, and more pregnant women were knowledgeable about vertical HIV transmission. Remaining challenges are to expand HIV screening to pregnant women at large and to effectively introduce rapid diagnostic tests for HIV in the delivery room. Such actions are expected to change the current situation, in which only 6.8% of infected children under observation had access to prophylaxis for vertical HIV transmission.     

Mother-to-child transmission of HIV: risk factors and missed opportunities for prevention among pregnant women attending health services in Goiânia, Goiás State, Brazil

The objectives of this study were to estimate the risk of vertical HIV transmission and assess the associated factors and missed opportunities for prevention in a cohort of HIV+ pregnant women (1995-2001) treated in Goiania, Goiás, Brazil, with follow-up of their children until 2005. Three data sources were compared: Information System on Reportable Diseases (SINAN), Information System on HIV+ Pregnant Women and Exposed Children (SISGHIV), and patient clinical charts. The study estimated the vertical transmission rates, factors associated with vertical transmission, and use of antiretroviral therapy. 276 HIV+ women were identified (322 pregnancies), and there were 70 HIV+ children. Overall risk of vertical HIV transmission was 27.8%. The vertical transmission rate was 40.8% in the group without prophylaxis and 1% in the group with adequate prophylaxis, i.e., a 97.5% reduction in transmission risk. Year of delivery, consultation with a specialist, and no history of injecting drug use were factors associated with adequate use of antiretroviral therapy. The study showed an important reduction in the risk of vertical transmission in pregnant women who received adequate therapy, besides identifying missed opportunities for prevention.     

AZT Availability in Illinois Birthing Hospitals: Is the Perinatal HIV Prevention Safety Net in Place?

Objectives: To prevent perinatal HIV transmission, providers must identify HIV status for all women in labor and newborns, and provide timely antiretroviral therapy if necessary. The objective of this study is to evaluate the availability and accessibility of zidovudine (AZT) in Illinois birthing hospitals. Methods: We surveyed all Illinois birthing hospital pharmacies by telephone in February 2005 regarding availability, accessibility, and protocols surrounding AZT use in the perinatal period. Results: All 137 pharmacies participated. Only 43.1% reported having syrup and IV AZT available and only 37.2% indicated the ability to have AZT available on labor and delivery within 30 min during off hours. Protocols for treating HIV positive women in labor and exposed newborns were available in only 37.2% of pharmacies while 72.4% had protocols for antiretroviral therapy for occupational post-exposure prophylaxis. Variables associated with pharmacies having AZT available included being a major academic hospital and serving a predominately (greater than 96%) white patient population. Timely provision of AZT was more likely to occur in urban, major academic hospitals serving a predominately white population. Conclusions: In order to further reduce perinatal HIV transmission, availability and timely access to both syrup and IV AZT must be improved in Illinois birthing hospitals.     

Pregnancy decisions among HIV-positive pregnant women in Mulago Hospital,Uganda

Pregnancy decisions in women infected by HIV pose important public health and social problems, as they increase risk of both heterosexual and vertical HIV transmission. We sought to explore and gain deeper understanding of reasons why women conceive when they are HIV-positive. Through 22 in-depth interviews and 6 focus-group discussions, motivations for conception among HIV-positive women who came for delivery in Mulago Hospital, Uganda were explored. Participants were selected by maximum variation sampling; and personal, biological, situational and environmental factors were explored. Data was analysed by content analysis. Awareness and belief in vertical transmission risk reduction strategies; disclosure of HIV status; awareness of spouse's HIV sero-status; availability of antiretroviral therapy; gender issues with desire for parenthood; stigma of HIV and childlessness; influence of partners and family members; and the impact of the health of self and family members were factors that motivate HIV-positive women to conceive or influence pregnancy decisions in spite of their sero-status.     

Preventing mother-to-child transmission of HIV in Africa

This article comments on the methods of reducing mother-to-child transmission of the HIV disease in the countries of Africa. Well-known interventions such as Cesarean sections, alternative feeding options, and antiretroviral drugs (zidovudine, lamivudine and nevirapine) have brought vertical transmission of HIV under a reasonable level of control where financial resources, technical infrastructure, and HIV testing exist. In sub-Saharan Africa, these effective interventions are beyond the current capacity of the country. However, the report explains that Africa is far from powerless to prevent vertical transmission of the disease. The countries already have commitment of political leaders, increased technical and financial resources, coordination of international support, integration into existing health services, and a combined approach to the problem. In addition, pilot projects and effective interventions have been implemented in the countries. Nevertheless, two strategies need urgent investigation. These include the use of a combination of nevirapine and zidovudine/lamivudine and an investigation of different approaches to the problem of HIV transmission through breast-feeding.     

Pregnancy and AIDS. Report of 9 cases

The pregnancy at women infected by the HIV characterizes by the risk of transmission of the HIV to the child. The goal of this retrospective study concerning 9 deliveries of women infected by the HIV cured in the Infectious Diseases Service and the Lalla Meryem's Maternity of Casablanca CHU Ibn-rochd during 10 years (1990-1999) is to specify the experience of two services of concerning plug in cost of the patients infected by HIV by trying to pull some a protocol of plug in cost. The antiretroviral therapy has been used in 8 cases out 9. The AZT long protocol has been used in 6 cases and the bitherapy in 2 cases. The delivery has taken place by the natural way under cover of AZT in all cases. All babies have received the AZT in syrup and none has been breastfed to the breast. Two newborns on 9 out 9 have been contaminated by the HIV.     

Antiretrovirals for vertical HIV transmission

This is a report on the presentation at the Sixth Conference on Retroviruses of a study of the efficacy of an antiretroviral therapy in reducing vertical transmission risk. The study investigated a short-course antiretroviral regimen (comprising AZT and 3TC) that was administered for 1 week beginning at the time of delivery. Transmission rates were determined 6 weeks later and 18 months later for babies and mothers. Preliminary results showed that the chance of babies becoming infected was reduced by 37%. Although this was not as high as the reduction achieved by other more elaborate regimens, in terms of cost-effectiveness the results were very impressive. This regimen has subsequently been used in Africa.     

HIV母婴传播机制研究进展

艾滋病是由人类免疫缺陷病毒引起的人类空前最严重的传染性疾病。母婴垂直传播是该病毒传播的一个重要方式 ,被感染的孕妇可以在宫内经胎盘、经阴道分娩以及产后经母乳感染胎儿和新生儿。该文通过对人类免疫缺陷病毒母婴传播的影响因素和各期传播机制进行综述 ,以期为今后制定更加合理的治疗方案提供理论依据     

Micronutrients and vertical transmission of HIV-1

ABSTRACT Vertical transmission of HIV from mother to infant can occur during pregnancy, at the time of delivery, or post-natally through breast-feeding and is a major factor in the continuing spread of HIV infection. Inadequate nutritional status may increase the risk of vertical HIV transmission by influencing mater-nal and child factors for transmission. The potential effects on these factors include impaired systemic immune function in pregnant women, fetuses, and children; an increased rate of clinical, immunologic, and virologic disease progression; impaired epithelial integrity of the placenta and genital tract; increased viral shedding in breast milk from inflammation of breast tissue; increased risk of low birth weight and preterm birth; and impaired gastrointestinal immune function and integrity in fetuses and children. Micronutrient deficiencies are prevalent in many HIV-infected populations, and numerous studies have reported that these deficiencies impair immune responses, weaken epithelial integrity, and are associated with accelerated HIV disease progression. Although low serum vitamin A concentrations were shown to be associated with an increased risk of vertical HIV transmission in prospective cohort studies, randomized, placebo-controlled trials have reported that vitamin A and other vitamin supplements do not appear to have an effect on HIV transmission during pregnancy or the intrapartum period. However, the ability of prenatal and postpartum micronutrient supplements to reduce transmission during the breast-feeding period is still unknown.     

两种高效抗反转录病毒方案预防艾滋病母婴传播的效果

目的:了解两种高效抗反转录病毒(HAART)方案预防艾滋病母婴传播的效果,为进一步合理选择母婴阻断抗病毒治疗方案提供依据。方法:采用两种方案(齐多夫啶AZT+拉米夫啶3TC+克力芝LPV/r和齐多夫啶AZT+拉米夫啶3TC+施多宁/奈韦拉平EFV/NVP)预防艾滋病母婴传播,对入组病例在服药前、孕36周及产后3个月进行CD4+T淋巴细胞计数和血浆HIV病毒载量测定。结果:共入组72例孕产妇,所生73例婴儿除1例因新生儿窒息死亡外,其余72例经早期HIVDNA-PCR核酸检测,结果均为阴性;血浆病毒载量在孕36周时最低(P<0.001);CD4+T淋巴细胞水平从治疗前至产后3个月呈增高趋势(P<0.001);治疗前后的病毒载量及CD4+T淋巴细胞平均水平两组间均无统计学差异(P>0.05)。结论:两种HAART方案预防艾滋病母婴传播效果显著,在病毒抑制和提高CD4+T淋巴细胞计数上两方案效果一致。     

Researcher predicts dramatic drop in infections in babies

According to Yvonne Bryson, head of the department of pediatrics at the Children's Hospital at the University of California, Los Angeles, the risk of HIV transmission from mother to child can be reduced to less than 2 percent by combining a number of existing and new therapies and birthing procedures. An estimated 1,000 children worldwide contract HIV each day. Studies have shown that transmission occurs in the womb, during delivery, and after birth through breast-feeding. According to a 1994 study, transmission can be reduced if HIV-positive women take AZT during pregnancy, labor and delivery. According to Bryson, other opportunities for reducing the risk include vaginal washing, topical or oral treatment of the infant, use of cesarean section, or immune-based therapies administered to either the mother or child. Additionally, nevirapine, approved for marketing in the United States, could reduce intrauterine transmission because it passes easily through the placenta to the baby. If Bryson is correct, there may be no need for lawmakers to mandate the testing of pregnant women.     

Pregnancy

The American College of Obstetricians and Gynecologists suggest that HIV-positive women should be offered a Caesarian delivery at 38 weeks into their pregnancy to reduce the risk of passing HIV to the newborn. The risk of a mother transmitting HIV to her newborn is 2 percent during a Caesarian delivery with AZT therapy for mother and baby, compared to 5 to 8 percent with AZT alone. A vaginal delivery without AZT, has a perinatal transmission rate of 25 percent. The precise mechanism by which a mother passes HIV to her baby remains unknown, but research suggests the virus is most likely transmitted during labor and delivery.     

U.S. Public Health Service Task Force recommendations for use of antiretroviral drugs in pregnant HIV-1-infected women for maternal health and interventions to reduce perinatal HIV-1 transmission in the United States.

These recommendations update the February 4,2002, guidelines developed by the Public Health Service for the use of zidovudine (ZDV) to reduce the risk for perinatal human immunodeficiency virus type 1 (HIV-1) transmission. This report provides healthcare providers with information for discussion with HIV-1-infected pregnant women to enable such women to make an informed decision regarding the use of antiretroviral drugs during pregnancy and use of elective cesarean delivery to reduce perinatal HIV-1 transmission. Various circumstances that commonly occur in clinical practice are presented, and the factors influencing treatment considerations are highlighted in this report. The Perinatal HIV Guidelines Working Group recognizes that strategies to prevent perinatal transmission and concepts related to management of HIV disease in pregnant women are rapidly evolving and will continually review new data and provide regular updates to the guidelines. The most recent information is available from the HIV/AIDS Treatment Information Service (available at http.//www.hivatis.org). In February 1994, the results of Pediatric AIDS Clinical Trials Group (PACTG) Protocol 076 documented that ZDV chemoprophylaxis could reduce perinatal HIV-1 transmission by nearly 70%. Epidemiologic data have since confirmed the efficacy of ZDV for reduction of perinatal transmission and have extended this efficacy to children of women with advanced disease, low CD4+ T-lymphocyte counts, and prior ZDV therapy. Additionally, substantial advances have been made in the understanding of the pathogenesis of HIV-1 infection and in the treatment and monitoring of persons with HIV-1 disease. These advances have resulted in changes in standard antiretroviral therapy for HIV-1-infected adults. More aggressive combination drug regimens that maximally suppress viral replication are now recommended. Although considerations associated with pregnancy may affect decisions regarding timing and choice of therapy pregnancy is not a reason to defer standard therapy. Use of antiretroviral drugs in pregnancy requires unique considerations, including the possible need to alter dosage as a result of physiologic changes associated with pregnancy the potential for adverse short- or long-term effects on the fetus and newborn, and the effectiveness of the drugs in reducing the risk for perinatal transmission. Data to address many of these considerations are not yet available. Therefore, offering antiretroviral therapy to HIV-1-infected women during pregnancy, whether primarily for HIV-1 infection, for reduction of perinatal transmission, or for both purposes, should be accompanied by a discussion of the known and unknown short- and long-term benefits and risks of such therapy to infected women and their infants. Standard antiretroviral therapy should be discussed with and offered to HIV-1-infected pregnant women. Additionally, to prevent perinatal transmission, ZDV chemoprophylaxis should be incorporated into the antiretroviral regimen.     

Evaluation of a regional pilot program to prevent mother-infant HIV transmission--Thailand, 1998-2000

Worldwide, approximately 2.2 million women and 600,000 infants are infected with human immunodeficiency virus (HIV) each year. Extended zidovudine prophylaxis and other antiretroviral and obstetric interventions and the avoidance of breast-feeding have reduced dramatically mother-infant HIV transmission in countries with adequate health-care resources. However, in developing countries, where the impact of HIV is greatest, implementation has been limited by the complexity and expense of these interventions. In Thailand, where approximately 15,000 infants are born to HIV-infected women each year, the Ministry of Public Health (MOPH) has collaborated with other organizations to identify simpler and more cost-effective interventions to reduce mother-infant HIV transmission. In 1998, a placebo-controlled clinical trial in Thailand using a simplified zidovudine regimen from 36 weeks' gestation until delivery reduced the risk for mother-infant transmission by 50%. In 1998, MOPH initiated a pilot program to prevent mother-infant HIV transmission in region 7, a rural area in northeastern Thailand with an antenatal HIV prevalence of approximately 1%, to assess program feasibility, effectiveness, and acceptability. This report summarizes an evaluation of the 2-year pilot program, which indicated that acceptance of HIV testing and adherence to zidovudine were high and HIV transmission was reduced. The findings demonstrate the feasibility of implementing programs to prevent mother-infant HIV transmission on a large scale in a developing country.     

Biological Correlates of Sexual Transmission of HIV Practical Consequences and Potential Targets for Public Health

The probability of sexual transmission of HIV depends on the infectiousness of the index case and the susceptibility of the sexual contact. The risk of HIV transmission is heterogeneous and may be greatest during the initial sexual contacts in a steady partnership. Several factors, including systemic and mucosal acquired protective immune-response might be responsible for the apparent decrease of per-sex-act risk of transmission in a given partnership over time. Biological studies can be used to better understand the complex information obtained by epidemiological surveys. The infectiousness of HIV depends on the inoculum, and virologic factors. The genital tract viral load of the index case is likely the most important determinant of transmission. At the population level, interventions that reduce the genital shedding of HIV by reducing systemic blood viral load and/or local inflammatory processes are likely to have a beneficial impact on HIV incidence. Antiretroviral drugs are likely to reduce sexual transmission of HIV. However, these drugs may not all prove equally. Compartmentalized HIV replication in the male and female genital tract have been observed. Treatment with antiretroviral drugs that poorly penetrate the genital tract harbour the risk of local production and spread of resistant viruses. In addition, increased risk taking behaviour could offset the benefits of reduced probability of transmission at the population level. Biological data about HIV transmission must be used to inform public health policies and optimize HIV prevention strategies.     

Biological Correlates of Sexual Transmission of HIV Practical Consequences and Potential Targets for Public Health Practical Consequences and Potential Targets for Public Health

The probability of sexual transmission of HIV depends on the infectiousness of the index case and the susceptibility of the sexual contact. The risk of HIV transmission is heterogeneous and may be greatest during the initial sexual contacts in a steady partnership. Several factors, including systemic and mucosal acquired protective immune-response might be responsible for the apparent decrease of per-sex-act risk of transmission in a given partnership over time. Biological studies can be used to better understand the complex information obtained by epidemiological surveys. The infectiousness of HIV depends on the inoculum, and virologic factors. The genital tract viral load of the index case is likely the most important determinant of transmission. At the population level, interventions that reduce the genital shedding of HIV by reducing systemic blood viral load and/or local inflammatory processes are likely to have a beneficial impact on HIV incidence. Antiretroviral drugs are likely to reduce sexual transmission of HIV. However, these drugs may not all prove equally. Compartmentalized HIV replication in the male and female genital tract have been observed. Treatment with antiretroviral drugs that poorly penetrate the genital tract harbour the risk of local production and spread of resistant viruses. In addition, increased risk taking behaviour could offset the benefits of reduced probability of transmission at the population level. Biological data about HIV transmission must be used to inform public health policies and optimize HIV prevention strategies.     

Reducing perinatal HIV transmission in developing countries through antenatal and delivery care, and breastfeeding: supporting infant survival by supporting women's survival

In 1998, a joint UNAIDS/UNICEF/WHO working group announced an initiative to pilot test an intervention to reduce perinatal transmission of human immunodeficiency virus (HIV), based on new guidelines on HIV and infant feeding. This intervention for developing countries includes short-course perinatal zidovudine (AZT) treatment and advice to HIV-positive women not to breastfeed their infants, where this can be done safely. The present paper raises questions about the extent of the public health benefit of this intervention, even though it may be cost-effective, due to the limited capacity of antenatal and delivery services to implement it fully. It argues that it is necessary to provide universal access to replacement feeding methods and support in their safe use, not only for women who have tested HIV-positive during pregnancy, but also for untested women who may also decide not to breastfeed, some of whom may be infected with HIV or may acquire HIV during the breastfeeding period. It further argues that additional funding, more staff, staff training, and improved capacity and resources are also needed to integrate this intervention successfully into antenatal and delivery care. The intervention will prevent some infants from getting HIV even in the absence of many of these changes. However, a comprehensive approach to HIV prevention and care in developing countries that includes both women and infants would promote better health and survival of women, which would in turn contribute to greater infant health and survival. If combination antiretroviral therapy in the latter part of pregnancy and/or during the breastfeeding period can be shown to be safe for infants, preliminary evidence suggests that it might reduce perinatal HIV transmission as effectively as the current intervention and, in addition, might allow the practice of breastfeeding to be preserved.     

Variations in Self-Rated Health Among Patients with HIV Infection

Purpose:To assess how patients with HIV who are enrolled in a clinical trials cohort rate their health and to compare their ratings with those of patients with HIV from 2 other cohorts: the HIV Cost and Services Utilization Study (HCSUS), and Adult AIDS Clinical Trials Group protocol 320 (ACTG 320). Methods: We analyzed baseline information for the 1649 subjects enrolled in the Adult AIDS Clinical Trials Group Longitudinal Linked Randomized Trials (ALLRT) study prior to March 2002 who had self-rated health data available. We compared those results with results from 2 other groups: HCSUS, the only nationally representative sample of people in care for HIV in the U.S., which conducted baseline interviews in 1996 and 1997, and ACTG 320, a randomized, double-blinded, placebo-controlled trial comparing a 3-drug antiretroviral regimen with a 2-drug combination, which enrolled subjects in the same general time frame as HCSUS. We used t tests, Pearson correlations, and linear regression to determine factors associated with self-rated health and z scores to compare results between cohorts. Results: The mean (SD) rating scale value on a 0–100 scale for ALLRT participants was 79.8 (16.8). Values were significantly lower for subjects who were older, had a history of injection drug use, had lower CD4 cell counts, or were beginning salvage antiretroviral therapy. Subjects in ALLRT reported significantly better self-rated health at baseline than those in HCSUS or ACTG 320 (11–12% higher rating scale values in ALLRT; p<0.05). When cohort differences were accounted for through regression and stratification, the differences in scores between subjects in ALLRT and HCSUS increased and the differences in scores between subjects in ALLRT and ACTG 320 diminished. Conclusions: Self-rated health varied significantly by age, CD4 count, injection drug use history, and salvage therapy status. Differences in self-rated health for clinical trials and non-clinical trials samples appear to be substantial and should be considered when applying trial results to clinical populations.     

HIV暴露未感染儿童预防性用药对其体格生长发育的影响

目的 了解广州市HIV暴露未感染（HEU）儿童预防性用药对其体格生长发育的影响。方法 数据来自国家“预防艾滋病、梅毒和乙肝母婴传播管理信息系统”实时监测收集的广州市HIV感染孕产妇及其所生儿童检测治疗与随访等信息,剔除婴儿死亡及感染HIV个案,共纳入564例HEU儿童。HEU儿童预防性用药方案分为3种情况：奈韦拉平（NVP）、齐多夫定（AZT）和未用药,采用广义估计方程等方法分析HEU儿童预防性用药对其体重、身长等的影响。结果 HEU儿童1月龄时,年龄别体重Z分、年龄别身长Z分略低于WHO的参考标准,服用AZT组消瘦发生率（17.5%）高于服用NVP组（6.2%）。儿童预防性服用NVP或AZT是HEU儿童年龄别身长Z分的保护因素,宫内暴露三联抗病毒药物是HEU儿童年龄别体重Z分、年龄别身长Z分的危险因素（P<0.05）。结论 1月龄HEU儿童体格生长发育状况欠佳,服用AZT的HEU儿童满月时消瘦发生率更高,应重点关注。