Detection of minority drug resistant mutations in Malawian HIV-1 subtype C-positive patients initiating and on first-line antiretroviral therapy.

BACKGROUND: Minority drug resistance mutations (DRMs) that are often missed by Sanger sequencing are clinically significant, as they can cause virologic failure in individuals treated with antiretroviral therapy (ART) drugs. OBJECTIVE: This study aimed to estimate the prevalence of minor DRMs among patients enrolled in a Malawi HIV drug resistance monitoring survey at baseline and at one year after initiation of ART. METHODS: Forty-one plasma specimens collected from HIV-1 subtype C-positive patients and seven clonal control samples were analysed using ultra-deep sequencing technology. RESULTS: Deep sequencing identified all 72 DRMs detected by Sanger sequencing at the level of ≥20% and 79 additional minority DRMs at the level of < 20% from the 41 Malawian clinical specimens. Overall, DRMs were detected in 85% of pre-ART and 90.5% of virologic failure patients by deep sequencing. Among pre-ART patients, deep sequencing identified a statistically significant higher prevalence of DRMs to nucleoside reverse transcriptase inhibitors (NRTIs) compared with Sanger sequencing. The difference was mainly due to the high prevalence of minority K65R and M184I mutations. Most virologic failure patients harboured DRMs against both NRTIs and non-nucleoside reverse transcriptase inhibitors (NNRTIs). These minority DRMs contributed to the increased or enhanced virologic failures in these patients. CONCLUSION: The results revealed the presence of minority DRMs to NRTIs and NNRTIs in specimens collected at baseline and virologic failure time points. These minority DRMs not only increased resistance levels to NRTIs and NNRTIs for the prescribed ART, but also expanded resistance to additional major first-line ART drugs. This study suggested that drug resistance testing that uses more sensitive technologies, is needed in this setting.

Use of laboratory test results in patient management by clinicians in Malawi.

BACKGROUND: Malawi has a high burden of infectious disease. The expansion of programmes targeting these diseases requires a strong laboratory infrastructure to support both diagnosis and treatment. OBJECTIVES: To assess the use of laboratory test results in patient management and to determine the requirements for improving laboratory services. METHODS: A cross-sectional study was conducted in 2012 to survey practising clinicians. Two hospitals were purposively selected for observations of clinicians ordering laboratory tests. Twelve management-level key informants were interviewed. Descriptive statistics were conducted. RESULTS: A total of 242 clinicians were identified and 216 (89%) were interviewed. Of these, 189 (87%) reported doubting laboratory test results at some point. Clinicians most often doubted the quality of haematology (67%), followed by malaria (53%) and CD4 (22%) test results. A total of 151 (70%) clinicians reported using laboratory tests results in patient management. Use of laboratory test results at all times in patient management varied by the type of health facility (P < 0.001). Ninety-one percent of clinicians reported that laboratories required infrastructure improvement. During 97 observations of clinicians' use of laboratory test results, 80 tests were ordered, and 73 (91%) of these were used in patient management. Key informants reported that the quality of laboratory services was good and useful, but that services were often unavailable. CONCLUSION: Gaps in the public laboratory system were evident. Key recommendations to enhance the use of laboratory test results in patient management were to strengthen the supply chain, reduce turn-around times, improve the test menu and improve the laboratory infrastructure.

Use of laboratory test results in patient management by clinicians in Malawi

Background: Malawi has a high burden of infectious disease. The expansion of programmes targeting these diseases requires a strong laboratory infrastructure to support both diagnosis and treatment.Objectives: To assess the use of laboratory test results in patient management and to determine the requirements for improving laboratory services. Methods: A cross-sectional study was conducted in 2012 to survey practising clinicians.Two hospitals were purposively selected for observations of clinicians ordering laboratory tests. Twelve management-level key informants were interviewed. Descriptive statistics were conducted. Results: A total of 242 clinicians were identified and 216 (89%) were interviewed. Of these; 189 (87%) reported doubting laboratory test results at some point. Clinicians most often doubted the quality of haematology (67%); followed by malaria (53%) and CD4 (22%) test results. A total of 151 (70%) clinicians reported using laboratory tests results in patient management. Use of laboratory test results at all times in patient management varied by the type of health facility (P 0.001). Ninety-one percent of clinicians reported that laboratories required infrastructure improvement. During 97 observations of clinicians' use of laboratory test results; 80 tests were ordered; and 73 (91%) of these were used in patient management. Key informants reported that the quality of laboratory services was good and useful; but that services were often unavailable. Conclusion: Gaps in the public laboratory system were evident. Key recommendations to enhance the use of laboratory test results in patient management were to strengthen the supply chain; reduce turn-around times; improve the test menu and improve the laboratory infrastructure

Evaluating the impact of prevention of mother-to-child transmission of HIV in Malawi through immunization clinic-based surveillance.

BACKGROUND: Prevention of mother-to-child transmission of HIV (PMTCT) programs can greatly reduce the vertical transmission rate (VTR) of HIV, and Malawi is expanding PMTCT access by offering HIV-infected pregnant women life-long antiretroviral therapy (Option B+). There is currently no empirical data on the effectiveness of Malawian PMTCT programs. This study describes a surveillance approach to obtain population-based estimates of the VTR of infants <3 months of age in Malawi immediately after the adoption of Option B+. METHODS AND FINDINGS: A sample of caregivers and infants <3 months from 53 randomly chosen immunization clinics in 4 districts were enrolled. Infant dried blood spot (DBS) samples were tested for HIV exposure with an antibody test to determine maternal seropositivity. Positive samples were further tested using DNA PCR to determine infant infection status and VTR. Caregivers were surveyed about maternal receipt of PMTCT services. Of the 5,068 DBS samples, 764 were ELISA positive indicating 15.1% (14.1-16.1%) of mothers were HIV-infected and passed antibodies to their infant. Sixty-five of the ELISA-positive samples tested positive by DNA PCR, indicating a vertical transmission rate of 8.5% (6.6-10.7%). Survey data indicates 64.8% of HIV-infected mothers and 46.9% of HIV-exposed infants received some form of antiretroviral prophylaxis. Results do not include the entire breastfeeding period which extends to almost 2 years in Malawi. CONCLUSIONS: The observed VTR was lower than expected given earlier modeled estimates, suggesting that Malawi's PMTCT program has been successful at averting perinatal HIV transmission. Challenges to full implementation of PMTCT remain, particularly around low reported antiretroviral prophylaxis. This approach is a useful surveillance tool to assess changes in PMTCT effectiveness as Option B+ is scaled-up, and can be expanded to track programming effectiveness for young infants over time in Malawi and elsewhere.

Prevalence of transmitted HIV drug resistance among newly diagnosed antiretroviral therapy-naive pregnant women in Lilongwe and Blantyre, Malawi.

In 2006, a survey of transmitted human immunodeficiency virus (HIV) drug resistance (TDR) was conducted in Lilongwe, Malawi. The survey followed the World Health Organization method to classify TDR to nucleoside reverse transcriptase inhibitors (NRTIs), nonnucleoside reverse transcriptase inhibitors (NNRTIs), and protease inhibitors (PIs) among primigravid women aged <25 years. Results of the 2006 survey showed <5% TDR in all drug classes. In 2009, TDR surveys using the same method were repeated in Lilongwe and expanded to Blantyre. Findings show that in Lilongwe TDR to NRTIs and PIs was <5%, whereas TDR to NNRTIs was 5%-15%. In Blantyre, TDR was <5% to all drug classes. Observed moderate TDR in Lilongwe is cause for concern and signals the need for closer monitoring of Malawi's antiretroviral therapy program.

A retrospective survey of HIV drug resistance among patients 1 year after initiation of antiretroviral therapy at 4 clinics in Malawi.

In 2004, Malawi began scaling up its national antiretroviral therapy (ART) program. Because of limited treatment options, population-level surveillance of acquired human immunodeficiency virus drug resistance (HIVDR) is critical to ensuring long-term treatment success. The World Health Organization target for clinic-level HIVDR prevention at 12 months after ART initiation is ≥ 70%. In 2007, viral load and HIVDR genotyping was performed in a retrospective cohort of 596 patients at 4 ART clinics. Overall, HIVDR prevention (using viral load ≤ 400 copies/mL) was 72% (95% confidence interval [CI], 67%-77%; range by site, 60%-83%) and detected HIVDR was 3.4% (95% CI, 1.8%-5.8%; range by site, 2.5%-4.7%). Results demonstrate virological suppression and HIVDR consistent with previous reports from sub-Saharan Africa. High rates of attrition because of loss to follow-up were noted and merit attention.

Prevalence of HIV drug resistance before and 1 year after treatment initiation in 4 sites in the Malawi antiretroviral treatment program.

Since 2004, the Malawi antiretroviral treatment (ART) program has provided a public health-focused system based on World Health Organization clinical staging, standardized first-line ART regimens, limited laboratory monitoring, and no patient-level monitoring of human immunodeficiency virus drug resistance (HIVDR). The Malawi Ministry of Health conducts periodic evaluations of HIVDR development in prospective cohorts at sentinel clinics. We evaluated viral load suppression, HIVDR, and factors associated with HIVDR in 4 ART sites at 12-15 months after ART initiation. More than 70% of patients initiating ART had viral suppression at 12 months. HIVDR prevalence (6.1%) after 12 months of ART was low and largely associated with baseline HIVDR. Better follow-up, removal of barriers to on-time drug pickups, and adherence education for patients 16-24 years of age may further prevent HIVDR.