Comparison of nevirapine (NVP) resistance in Ugandan women 7 days vs. 6-8 weeks after single-dose nvp prophylaxis: HIVNET 012

We compared nevirapine (NVP) resistance (NVPR) mutations in maternal plasma 7 days vs. 6-8 weeks after single-dose NVP prophylaxis. In the HIVNET 012 trial, Ugandan women received a single dose of NVP in labor for prevention of HIV-1 mother-to-child transmission. NVPR mutations were detected in 70 (25%) of 279 women 6-8 weeks after NVP. Samples collected 7 days after NVP were analyzed from a subset of those 279 women. Genotyping was performed with the ViroSeq HIV-1 Genotyping System. NVPR was analyzed using paired samples from 7 days and 6-8 weeks after NVP. Sixty-five women had genotyping results obtained for samples collected at both 7 days and 6-8 weeks post-NVP. Twenty-one (32%) of those women had NVPR mutations detected in one or both samples. This included three women with NVPR at 7 days only, seven with NVPR at 6-8 weeks only, and 11 with NVPR at both time points. Eight women had >1 NVPR mutation detected 7 days after NVP. Y181C was the most common NVPR mutation detected at 7 days, whereas K103N was the most common NVPR mutation detected at 6-8 weeks. We conclude that NVPR may be detected in women as early as 7 days after single-dose NVP. Complex patterns of NVPR are detected in some women. The Y181C NVPR mutation often fades from detection by 6-8 weeks. In contrast, the K103N mutation emerges more slowly, but often remains detectable 6-8 weeks after NVP.

Risk factors and cumulative incidence of anaemia among human immunodeficiency virus-infected children in Uganda

Anaemia has not been well characterised among HIV-infected children in sub-Saharan Africa. Baseline prevalence and cumulative incidence of anaemia (haemoglobin < 110 g/L) were 91.7% and 100% and, for moderate anaemia (haemoglobin < 90 g/L), were 35.1% and 58.4%, respectively, among 225 HIV-infected children followed from 9 to 36 months of age. Hospitalisation, suspected tuberculosis, malaria and height-for-age Z-score <-2 were significantly associated with moderate anaemia. Moderate anaemia and weight-for-height Z-score <-2 were associated with mortality. Anaemia is common and associated with increased mortality in HIV-infected children.

Selection and fading of resistance mutations in women and infants receiving nevirapine to prevent HIV-1 vertical transmission (HIVNET 012)

OBJECTIVE

To examine the emergence and fading of NVP resistance (NVP(R)) mutations in HIV-1-infected Ugandan women and infants who received single dose NVP to prevent HIV-1 vertical transmission.

DESIGN

We examined NVP(R) in women and infants who received NVP in the HIVNET 012 clinical trial, including 41 out of 48 women with infected infants, 70 randomly-selected women with uninfected infants, and 33 out of 49 infected infants.

METHODS

Plasma HIV-1 was analyzed using the Applied Biosystems ViroSeq HIV-1 Genotyping System.

RESULTS

NVP(R) mutations were detected in 21 out of 111 (19%) women tested 6-8 weeks after delivery. The rate of NVP(R) was similar among women whose infants were or were not HIV-1 infected. K103N was the most common mutation detected. NVP(R) mutations faded from detection within 12-24 months in all 11 evaluable women. High baseline viral load and low baseline CD4 cell count were associated with development of NVP(R). NVP(R) mutations were detected in 11 out of 24 (46%) evaluable infants who were infected by 6-8 weeks of age. The most common NVP(R) mutation detected in infants was Y181C. Those mutations faded from detection by 12 months of age in all seven evaluable infants. Of nine evaluable infants with late HIV-1 infection, only one had evidence of NVP(R).

CONCLUSIONS

NVP(R) was detected more frequently in infants than women following NVP prophylaxis, and different patterns of NVP(R) mutations were detected in women versus infants. NVP(R) was detected infrequently in infants with late HIV-1 infection. NVP-resistant HIV-1 faded from detection in women and infants over time.

Impact of human immunodeficiency virus type 1 (hiv-1) subtype on women receiving single-dose nevirapine prophylaxis to prevent hiv-1 vertical transmission (hiv network for prevention trials 012 study)

In Uganda, the HIV Network for Prevention Trials (HIVNET) 012 study recently demonstrated that single-dose nevirapine (Nvp) prophylaxis is effective for preventing mother-to-child transmission (MTCT) of human immunodeficiency virus type 1 (HIV-1). This exploratory study examines the relationship between HIV-1 subtype, MTCT, and the development of Nvp resistance (Nvp(R)) in women enrolled in HIVNET 012. For 102 women (32 whose infants were HIV-1 infected by age 6-8 weeks and 70 whose infants were uninfected), HIV-1 subtypes included 50 (49%) subtype A, 35 (34%) subtype D, 4 (4%) subtype C, 12 (12%) recombinant subtype, and 1 unclassified. There was no apparent difference in the rate of MTCT among women with subtype A versus D (adjusted odds ratio [OR], 1.24; 95% confidence interval [CI], 0.45-3.43). Nvp(R) mutations were detected more frequently at 6-8 weeks postpartum in women with subtype D than in women with subtype A (adjusted OR, 4.94; 95% CI, 1.21-20.22). Additional studies are needed to further define the relationship between HIV-1 subtype and Nvp(R) among women receiving Nvp prophylaxis.

Relation of vitamin A and carotenoid status to growth failure and mortality among Ugandan infants with human immunodeficiency virus

Although growth failure is common during pediatric infection with human immunodeficiency virus (HIV) and associated with increased mortality, the relation of specific nutrition factors with growth and mortality has not been well characterized. A longitudinal study was conducted with 194 HIV-infected infants in Kampala, Uganda. Plasma vitamin A, carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, and lutein/zeaxanthin), and vitamin E were measured at age 14 wk, and weight and height were followed up to age 12 mo. Vitamin A and low plasma carotenoid concentrations were predictive of decreased weight and height velocity. Between ages 14 wk and 12 mo, 32% of infants died. Underweight, stunting, and low concentrations of plasma carotenoids were associated with increased risk of death in univariate analyses. Plasma vitamin A concentrations were not associated with risk of death. In a final multivariate model adjusting for weight-for-age, plasma beta-carotene was significantly associated with increased mortality (odds ratio: 3.16, 95% confidence interval: 1.38 to 7.21, P < 0.006). These data suggest that low concentrations of plasma carotenoids are associated with increased risk of death during HIV infection among infants in Uganda.

Measles infection in HIV-infected African infants

Measles infection remains a serious threat to child survival in the developing world despite vaccination and treatment with vitamin A. This report reviews the epidemiology of measles in HIV-infected children in Africa. In hospitalized infants, the rate of malnutrition before measles and the rate of death after measles are both higher in HIV-positive than in HIV-negative infants. However, the rates of pneumonia and diarrhea in infants hospitalized with measles are the same in HIV-positive as in HIV-negative infants. In an autopsy study, measles was associated with death in HIV-positive children, only for those over 15 months of age. A cohort study found that infants of HIV-positive women were more likely than infants of HIV-negative women to have measles before 9 months of age, although the rates of complications did not differ between the two groups. The HIV status of the infants and the measles serology were too incomplete to draw firm conclusions, though only 1 of 54 infants tested was seropositive for measles at 6 months of age. In the context of the HIV epidemic, further work is needed to determine the risk of measles and its complications in HIV-positive infants and the optimal age of measles immunization.

Identification of diverse HIV type 1 subtypes and dual HIV type 1 infection in pregnant Ugandan women

Vertical (mother-to-child) transmission accounts for the majority of pediatric HIV-1 infections. Many factors are involved in vertical transmission, however it is not clear which factors are most important for determining whether a mother will transmit HIV-1 to her infant. It has been suggested that HIV-1 subtype may influence vertical transmission and that subtype D viruses may be less likely to be transmitted in this setting. We analyzed HIV-1 gp120 V3 region sequences from the plasma of 20 pregnant Ugandan women of known transmission status who did not receive antiretroviral prophylaxis. V3 regions were cloned, sequenced, and subtyped by phylogenetic analysis. Among 11 women who transmitted HIV-1 to their infants, we detected subtypes A, C, D, and G. Two of the transmitters had dual infection with subtypes A and D. In addition, a third was infected with two distinct strains of subtype G viruses. HIV-1 subtype A and D viruses were found in 9 women who did not transmit the virus to their infants. This study reveals that pregnant Ugandan women harbor diverse HIV-1 subtypes, including women who transmit HIV-1 to their infants. Transmission of HIV-1 with subtype D V3 regions was confirmed in 4 of the 11 transmitters, including 2 who had dual infection with subtype A and D HIV-1.

Identification of the K103N resistance mutation in Ugandan women receiving nevirapine to prevent HIV-1 vertical transmission

OBJECTIVE

A recent trial in Uganda demonstrated that a simple, inexpensive regimen of nevirapine (NVP) prophylaxis can dramatically reduce HIV-1 vertical transmission risk. In this regimen, women receive a single dose of NVP at the onset of labor and infants receive a single dose of NVP within 72 h of birth. The objective of this study was to determine whether HIV-1 variants with NVP resistance mutations were selected in Ugandan women who received this regimen in the Phase I/II trial HIVNET 006.

METHODS

Reverse transcriptase (RT) sequences from plasma HIV-1 were analyzed from 15 women 6 weeks after NVP dosing. RT sequences from plasma collected prior to NVP dosing were also analyzed.

RESULTS

The K103N NVP resistance mutation was detected 6 weeks after NVP administration in three (20%) out of 15 women (95% confidence interval, 0-40%). Pre-dose samples were available from two of the three women; both pre-dose samples lacked the mutation. Other NVP resistance mutations were absent from all 15 women. Women with the K103N mutation had a longer median NVP elimination half-life, decreased median oral clearance, and increased median area under the concentration time curve than those without the mutation. An evaluable sample was obtained from one of these three women 33 months after delivery; the K103N mutation was not detected in that sample.

CONCLUSIONS

This preliminary study demonstrates that HIV-1 with the RT K103N mutation can be detected in some Ugandan women following a single dose of NVP. This suggests that non-nucleoside RT inhibitor resistance may be selected in some people by single dose NVP prophylaxis. Pharmacokinetic data suggested that a more prolonged exposure to NVP after dosing may favor selection of NVP-resistant HIV-1.

Cost effectiveness of single-dose nevirapine regimen for mothers and babies to decrease vertical HIV-1 transmission in sub-Saharan Africa

BACKGROUND

Identification of economical interventions to decrease HIV-1 transmission to children is an urgent public-health priority in sub-Saharan Africa. We assessed the cost effectiveness of the HIVNET 012 nevirapine regimen.

METHODS

We assessed cost effectiveness in a hypothetical cohort of 20,000 pregnant women in sub-Saharan Africa. Our main outcome measures were programme cost, paediatric HIV-1 cases averted, cost per case averted, and cost per disability-adjusted life-year (DALY). We compared HIVNET 012 with other short-course antiretroviral regimens. We also compared two implementation strategies: counselling and HIV-1 testing before treatment (targeted treatment), or nevirapine for all pregnant women (universal treatment, no counselling and testing). We did univariate and multivariate sensitivity analyses.

FINDINGS

For universal treatment with 30% HIV-1 seroprevalence, the HIVNET 012 regimen would avert 603 cases of HIV-1 in babies, cost US$83,333, and generate 15,862 DALYs. The associated cost-effectiveness ratios were $138 per case averted or $5.25 per DALY. At 15% seroprevalence, the universal treatment option would cost $83,333 and avert 302 cases at $276 per case averted or $10.51 per DALY. For targeted treatment at 30% seroprevalence, HIVNET 012 would cost $141,922 and avert 476 cases at $298 per case averted or $11.29 per DALY. With seroprevalence higher than 3.0% for universal and 4.5% for targeted treatment, the HIVNET 012 regimen was likely to be as cost effective as other public-health interventions. The cost effectiveness of HIVNET 012 was robust under a wide range of parameters in the sensitivity analysis.

INTERPRETATION

The HIVNET 012 regimen can be highly cost-effective in high seroprevalence settings. In lower seroprevalence areas, when multidose regimens are not cost effective, nevirapine therapy could have a major public-health impact at a reasonable cost.

Intrapartum and neonatal single-dose nevirapine compared with zidovudine for prevention of mother-to-child transmission of HIV-1 in Kampala, Uganda: HIVNET 012 randomised trial

BACKGROUND

The AIDS Clinical Trials Group protocol 076 zidovudine prophylaxis regimen for HIV-1-infected pregnant women and their babies has been associated with a significant decrease in vertical HIV-1 transmission in non-breastfeeding women in developed countries. We compared the safety and efficacy of short-course nevirapine or zidovudine during labour and the first week of life.

METHODS

From November, 1997, to April, 1999, we enrolled 626 HIV-1-infected pregnant women at Mulago Hospital in Kampala, Uganda. We randomly assigned mothers nevirapine 200 mg orally at onset of labour and 2 mg/kg to babies within 72 h of birth, or zidovudine 600 mg orally to the mother at onset of labour and 300 mg every 3 h until delivery, and 4 mg/kg orally twice daily to babies for 7 days after birth. We tested babies for HIV-1 infection at birth, 6-8 weeks, and 14-16 weeks by HIV-1 RNA PCR. We assessed HIV-1 transmission and HIV-1-free survival with Kaplan-Meier analysis.

FINDINGS

Nearly all babies (98.8%) were breastfed, and 95.6% were still breastfeeding at age 14-16 weeks. The estimated risks of HIV-1 transmission in the zidovudine and nevirapine groups were: 10.4% and 8.2% at birth (p=0.354); 21.3% and 11.9% by age 6-8 weeks (p=0.0027); and 25.1% and 13.1% by age 14-16 weeks (p=0.0006). The efficacy of nevirapine compared with zidovudine was 47% (95% CI 20-64) up to age 14-16 weeks. The two regimens were well tolerated and adverse events were similar in the two groups.

INTERPRETATION

Nevirapine lowered the risk of HIV-1 transmission during the first 14-16 weeks of life by nearly 50% in a breastfeeding population. This simple and inexpensive regimen could decrease mother-to-child HIV-1 transmission in less-developed countries.

A phase I/II study of the safety and pharmacokinetics of nevirapine in HIV-1-infected pregnant Ugandan women and their neonates (HIVNET 006)

OBJECTIVE

To determine the safety, pharmacokinetics, tolerance, antiretroviral activity, and infant HIV infection status after giving a single dose of nevirapine to HIV-1-infected pregnant women during labor and their newborns during the first week of life.

DESIGN

An open label phase I/II study.

SETTING

Tertiary care hospital, Kampala, Uganda.

PATIENTS AND INTERVENTIONS

Nevirapine, 200 mg, was given as a single dose during labor to 21 HIV-1-infected pregnant Ugandan women. In cohort 1, eight infants did not receive nevirapine whereas in cohort 2, 13 infants received a single dose of nevirapine, 2 mg/kg, at 72 h of age.

OUTCOMES

The number and type of adverse events; nevirapine concentrations in the plasma and breast milk; maternal plasma HIV-1 RNA copy number before and up to 6 weeks after delivery; and HIV-1 infection status of the infants were monitored.

RESULTS

Nevirapine was well tolerated by women and infants; no serious adverse events that were related to nevirapine were observed. Median nevirapine concentration in the women at delivery was 1623 ng/ml (range 238-2356 ng/ml); median cord/maternal blood ratio of 0.75 (0.37-0.93). The median half-life in women was 61.3 h (27-90 h) and the transplacental nevirapine half-life in infants who did not receive a neonatal dose was 54 h. The median half-life after a single dose at 72 h in infants was 46.5 h. During the first week of life, the median colostrum/breast milk to maternal plasma nevirapine concentration was 60.5% (25-122%). The median nevirapine concentration in breast milk 1 week after delivery was 103 ng/ml (25-309 ng/ml). Plasma nevirapine concentrations were above 100 ng/ml in all infants from both cohorts tested at age 7 days. Maternal HIV-1 RNA levels decreased by a median of 1.3 logs at 1 week postpartum, and returned to baseline by 6 weeks postpartum. Detectable plasma HIV-1 RNA was observed in one out of 22 (4.5%) infants at birth; three out of 21 (14%) at 6 weeks; and four out of 21 (19%) at 6 months of age.

CONCLUSION

The administration of a single dose of nevirapine to women during labor and to their newborns at 72 h was well tolerated and showed potent antiretroviral activity in the women at 1 week after dosing without rebound above baseline 6 weeks after a single dose. The nevirapine concentration was maintained above the target of 100 ng/ml in infants at age 7 days, even in those infants not receiving a neonatal dose. This regimen has promise as prophylaxis against intrapartum and early breast milk transmission in a breastfeeding population.

Detection of human immunodeficiency virus type 1 (HIV-1) DNA and p24 antigen in breast milk of HIV-1-infected Ugandan women and vertical transmission

OBJECTIVE

To determine the correlation between the detection of human immunodeficiency virus type 1 (HIV-1) in breast milk, the duration of breastfeeding, and vertical transmission of HIV-1 infection in Ugandan women.

METHODS

A prospective study of HIV-1 infection in pregnant Ugandan women and their infants has been ongoing since 1990 with follow-up of mother-infant pairs for at least 2 years. Expressed breast milk specimens were collected from 201 HIV-1-seropositive and 86 HIV-1-seronegative Ugandan women approximately 6 weeks after delivery. The presence of HIV-1 DNA in the cellular fraction of the breast milk was detected by polymerase chain reaction (PCR), and HIV-1 p24 antigen was detected in the cell-free breast milk supernatant using p24 antigen enzyme immunoassay (EIA) after immune complex dissociation (ICD). The duration of breastfeeding and the clinical status of the mothers and their children were recorded. HIV-1 EIA, Western blot, PCR, or p24 antigen detection were used for the determination of the HIV-1 infection status of the children.

RESULTS

Of the 201 HIV-1-infected women studied, 47 had HIV-1-infected children, 143 had children who seroreverted, and 11 had children of indeterminate status. Breast milk supernatants were available for ICD p24 antigen testing from 188 of the HIV-1-infected women and none had detectable p24 antigen. Breast milk cell pellets were available and contained amplifiable DNA in 125 of the HIV-1-infected women (20 transmitters, 104 nontransmitters, 1 indeterminate). HIV-1 DNA was detected by PCR in 72% (75/104) of nontransmitters and 80% (16/20) of the transmitters. The duration of breastfeeding by transmitter mothers (15.8 months) was not significantly different from nontransmitter mothers (14.4 months).

CONCLUSIONS

No correlation was found between the detection of HIV-1 in breast milk or the duration of breastfeeding and transmission of HIV-1 infection in this study of Ugandan women.

Maternal HIV-1 RNA serum levels at delivery and vertical transmission in Uganda

OBJECTIVE

To evaluate the clinical utility of maternal HIV-1 RNA serum levels at delivery in predicting the rate of HIV-1 vertical transmission.

DESIGN AND METHODS

HIV-1 RNA levels were determined by the Roche Amplicor Monitor assay in serum specimens collected at the time of delivery from 94 transmitting and 107 nontransmitting infected mothers and 12 seronegative mothers in Uganda. Nonparametric Wilcoxon-Rank sum tests were used to identify significant differences in medians and RNA level distributions by transmission status.

RESULTS

Mean HIV-1 RNA copies/mL for transmitters was 3419 +/- 7489 copies/mL versus 2483 +/- 8954 copies/mL for nontransmitters. There was a significant difference in medians and HIV-1 RNA serum level distributions between transmitting and nontransmitting mothers (p = 0.0039). However, the predictive value for any given HIV-1 RNA level for HIV-1 vertical transmission was poor.

CONCLUSION

Maternal HIV-1 RNA serum levels at delivery are significantly higher in transmitting mothers versus nontransmitting mothers, but appear to be of limited value in predicting HIV-1 vertical transmission using the Roche Amplicor Monitor assay in Uganda.

Lack of association between anti-V3 loop antibodies and perinatal transmission of HIV-1 in Kampala, Uganda

This study evaluated the association between reactivity of maternal antibody to human immunodeficiency virus type 1 (HIV-1) V3 loop peptides and perinatal transmission in Uganda. Plasma from 40 HIV-1-infected mothers (20 transmitting and 20 nontransmitting mothers) and 31 uninfected mothers in Uganda were tested for reactivity and antibody titer to synthetic peptides representing V3 loop sequences from HIV-1 strains MN, SF2, LAI, ZR6, and CM235 and consensus peptides CA, CB, and CD. No significant differences were found between 20 transmitting mothers and 20 nontransmitting mothers in terms of percent reactivity or titer of antibody to any of the V3 loop peptides tested. Use of a multivariable logistic model to adjust for beta-2 microglobulin level as a confounding variable of stage of infection did not help demonstrate an association except possibly for the ZR6 peptide. These data suggest that neither reactivity nor maternal antibody titer to V3 loop peptides are protective against perinatal transmission of HIV-1 in Uganda.

A rapid manual method for CD4+ T-cell quantitation for use in developing countries

OBJECTIVE

To evaluate a manual method (Cytosphere) for quantifying CD4+ T-cell numbers.

DESIGN

Cross-sectional study of HIV-1-seronegative and HIV-1-seropositive individuals evaluated for absolute CD4 counts by both standardized flow cytometric measurements and manual Cytosphere technology using a hemacytometer.

SETTING

University research hospitals in both the United States and Africa.

PATIENTS, PARTICIPANTS

Blood specimens from 382 patients were evaluated. These were broken down into 294 samples obtained from HIV-1-seropositive patients and 88 samples obtained from HIV-1-seronegative patients.

INTERVENTIONS

None.

OUTCOME MEASURED

Absolute CD4 cell number.

RESULTS

Evaluation of samples obtained from HIV-1 patients in both the United States and Africa demonstrated an overall correlation of the Cytosphere assay with flow cytometry of 0.912 (95% confidence interval, 0.895-0.928; P < 0.001). When samples were stratified based on CD4+ T-cell counts determined by flow cytometry, the Cytosphere assay had a 96% predictive value for correctly identifying individuals with CD4 T-cell counts > 200 x 10(6)/l and a 92% predictive value for correctly identifying individuals with CD4 T-cell counts < 200 x 10(6)/l.

CONCLUSIONS

This assay appears to have the potential for the quantitation of CD4 cells in the limited laboratory facilities in developing countries and to have a strong correlation with standard flow cytometric technology.

Beta 2-microglobulin, HIV-1 p24 antibody and acid-dissociated HIV-1 p24 antigen levels: predictive markers for vertical transmission of HIV-1 in pregnant Ugandan women

OBJECTIVES

To evaluate the clinical utility of plasma beta 2-microglobulin (beta 2M) levels, acid-dissociated HIV-1 p24 antigen, and HIV-1 p24-antibody titers in predicting HIV-1 vertical transmission in 227 HIV-1-infected Ugandan pregnant women.

DESIGN

Plasma beta 2M levels, acid-dissociated HIV-1 p24-antigen positivity, and HIV-1 p24-antibody titers were determined using commercial enzyme immunoassays (EIA) in a Ugandan cohort of 52 HIV-1-seropositive transmitting mothers, 175 HIV-1-seropositive non-transmitting mothers, and 52 seronegative mothers within 6 weeks prior to delivery.

RESULTS

Transmitter mothers had significantly higher plasma concentrations of beta 2M (1.80 +/- 1.13 mg/l) than non-transmitter seropositive mothers (1.32 +/- 0.81 mg/l; P = 0.0013). Similarly, a significantly higher proportion of transmitter mothers had detectable p24 antigen than non-transmitter mothers [six out of 51 (11.8%) versus six out of 173 (3.5%); P = 0.03]. Compared with the vertical transmission rate of 23% in the seropositive group, the positive predictive values of a beta 2M level > 1.5 mg/l or detectable HIV-1 p24 antigen for vertical transmission were 34 and 50%, respectively. Five of six (83.3%) seropositive mothers with both a beta 2M level > 1.5 mg/l and detectable p24 antigenemia transmitted HIV-1 infection to their infants compared with 25 of 124 (20.2%) seropositive mothers with values below the cut-off values for both tests (P = 0.00249). However, beta 2M was not found to be a significant independent predictor of vertical transmission when analyzed in a multivariate model with p24 antigenemia. There was no significant difference in HIV-1 p24-antibody titers in transmitter mothers versus non-transmitter mothers (P = 0.299).

CONCLUSION

beta 2M levels and acid-dissociated HIV-1 p24-antigen assays may be used to predict which HIV-1-infected pregnant women are at greatest risk for vertical transmission. However, only the p24-antigen test was independently predictive of vertical transmission and its clinical utility is limited.

Non-isotopic polymerase chain reaction methods for the detection of HIV-1 in Ugandan mothers and infants

Two non-isotopic polymerase chain reaction (PCR) methods were evaluated by testing blood from 41 HIV-1-seropositive and 16 HIV-1-seronegative Ugandan mothers and 56 of their children (aged 0.5-15.0 months). Amplification of HIV-1 sequences was performed in duplicate using a biotinylated primer pair to the gag region (SK 462-431) and nested primer pairs (JA 17-20) to the pol region of HIV-1. gag sequences were hybridized using a microtiter plate coated with the SK 102 probe followed by colorimetric detection using an avidin-horseradish peroxidase conjugate and tetramethylbenzidine/peroxide substrate. pol sequences were detected on agarose gel stained with ethidium bromide. Results of HIV-1 PCR analysis showed that 40 out of 41 (98%) seropositive mothers and 10 out of 29 (34%) seropositive children had detectable HIV-1 gag and pol sequences. None of the 16 seronegative mothers nor 27 seronegative or Western blot-indeterminate children had detectable HIV-1 sequences. Our results suggest that non-isotopic PCR methods are sensitive, specific, and potentially useful in the early diagnosis of HIV-1 infection in developed and developing countries.