Cost-effectiveness of tenofovir prophylaxis during pregnancy for the elimination of mother-to-child transmission of the hepatitis B virus: real-world analysis from Thailand.

OBJECTIVE: Despite implementing hepatitis B immunoglobulin (HBIG) and vaccination, data suggest it would not be sufficient to reach the elimination targets. Tenofovir disoproxil fumarate (TDF) has been added to the Thai national standards of care for prevention of transmission of the hepatitis B virus during birth. To optimise national strategies in Thailand, we assessed TDF's effectiveness for prevention of mother-to-child transmission and conducted cost-effectiveness analyses of different TDF-based strategies. RESEARCH DESIGN AND METHODS: We retrospectively reviewed medical records of mother and infant pairs whose mothers were positive for hepatitis B e-antigen (HBeAg) and received TDF to prevent maternal transmission of viral hepatitis B during 2018-2020. Based on the available data on transmission rate, we also applied a decision tree to estimate the cost-effectiveness of different TDF-based strategies to eligible mothers. These included: (1) HBIG for all hepatitis B virus (HBV) exposed infants; (2) HBIG for only infants of HBeAg-positive mothers ('HBIG for e-positive') and (3) without HBIG to infants ('HBIG-free'). The incremental cost-effectiveness ratio between the different strategies and baseline intervention without TDF was calculated. The one-way sensitivity analysis was used to adjust prevalence of HBeAg-positive mothers, cost of HBIG, cost of TDF and transmission rate. RESULTS: Of 223 infants enrolled, 212 (95.0%) received HBIG, while 11 (5.0%) did not. None of the infants had chronic HBV infection. The most cost-saving intervention was 'HBIG-free' followed by 'HBIG for e-positive'. The one-way sensitivity demonstrated that the results were reasonably robust to changes. The cost-saving was greater with a higher hepatitis B virus surface antigen (HBsAg) prevalence. The HBIG-free strategy remained best at 0%-1.4% transmission rates, meeting the additional target for eliminations. CONCLUSION: The study is the first cost-effectiveness analyses to provide evidence supporting an HBIG-free strategy in an antiviral era. This approach should be considered to prevent mother-to-child transmission in resource-constrained settings, particularly in countries with a high HBsAg prevalence.

Elimination of Mother-to-Child Transmission of HIV - Thailand.

Thailand experienced a generalized human immunodeficiency virus (HIV) epidemic during the 1990s. HIV prevalence among pregnant women was 2.0% and the mother-to-child transmission (MTCT) rate was >20% (1-3). In June 2016, Thailand became the first country in Asia to validate the elimination of MTCT by meeting World Health Organization (WHO) targets. Because Thailand's experience implementing a successful prevention of MTCT program might be instructive for other countries, Thailand's prevention of MTCT interventions, outcomes, factors that contributed to success, and challenges that remain were reviewed. Thailand's national prevention of MTCT program has evolved with prevention science from national implementation of short course zidovudine (AZT) in 2000 to lifelong highly active antiretroviral therapy regardless of CD4 count (WHO option B+) in 2014 (1). By 2015, HIV prevalence among pregnant women had decreased to 0.6% and the MTCT rate to 1.9% (the elimination of MTCT target is <2% for nonbreastfeeding populations) (4). A strong public health infrastructure, committed political leadership, government funding, engagement of multiple partners, and a robust monitoring system allowed Thailand to achieve this important public health milestone.

Uptake of early infant diagnosis in Thailand's national program for preventing mother-to-child HIV transmission and linkage to care, 2008-2011.

INTRODUCTION: Early infant diagnosis (EID) has been a component of Thailand's prevention of mother-to-child HIV transmission (PMTCT) programme since 2007. This study assessed the uptake, EID coverage, proportion of HIV-exposed infants receiving a definitive HIV diagnosis, mother-to-child transmission (MTCT) rates and linkage to HIV care and treatment. METHODS: Infant polymerase chain reaction (PCR) testing data from the National AIDS Program database were analyzed. EID coverage was calculated as the percentage of number of HIV-exposed infants receiving ≥ 1 HIV PCR test divided by the number of HIV-exposed infants estimated from HIV prevalence and live-birth registry data. Definitive HIV diagnosis was defined as having two concordant PCR results. MTCT rates were calculated based on infants tested with PCR and applied as a best-case scenario, and a sensitivity analysis was used to adjust these rates in average and worst scenarios. We defined linkage to HIV care as infants with at least one PCR-positive test who were registered with Thailand's National AIDS Program. Chi-squared tests for linear trend were used to analyze changes in programme coverage. RESULTS: For 2008 to 2011, the average EID coverage rate increased from 54 to 76% (p < 0.001), with 65% coverage (13,761/21,099) overall. The number of hospitals submitting EID samples increased from 458 to 645, and the percentage of community hospitals submitting samples increased from 75 to 78% (p = 0.044). A definitive HIV diagnosis was made for 10,854 (79%) infants during this period. The adjusted MTCT rates had significantly decreasing trends in all scenarios. Overall, an estimated 53% (429/804) of HIV-infected infants were identified through the EID programme, and 80% (341/429) of infants testing positive were linked to care. The overall rate of antiretroviral treatment (ART) initiation within one year of age was 37% (157/429), with an increasing trend from 28 to 52% (p < 0.001). CONCLUSIONS: EID coverage increased and MTCT rates decreased during 2008 to 2011; however, about half of HIV-infected infants still did not receive EID. Most HIV-infected infants were linked to care but less than half initiated ART within one year of age. Active follow-up of HIV-exposed infants to increase early detection of HIV infection and early initiation of ART should be more widely implemented.

Compliance with and outcomes of CD4-based national guidelines for prevention of mother-to-child transmission of HIV for Thailand, 2006-2007.

The 2006 Thailand national prevention of mother-to-child transmission of HIV (PMTCT) guidelines recommended antiretroviral (ARV) regimen use during antenatal care (ANC) be based on CD4 results: highly active antiretroviral therapy (HAART) should be used for a CD4 < 200 cells/mm(3) and zidovudine/single-dose nevirapine should be used for a CD4 count > or = 200 cell/mm(3). We evaluated compliance with and outcomes of these guidelines. We conducted a retrospective chart review of HIV-infected women and their infants born during October 2006 - December 2007 at 27 hospitals in 11 provinces of Thailand. The infant HIV-infection status was determined using laboratory test results and death reports. Mother-infant pairs were classified as fully, partially, or non-compliant with PMTCT guidelines based on CD4 testing history and ARV received. Factors associated with compliance were analyzed using univariate and multivariate generalized estimating equations (GEE). Among 875 mother-infant pairs reviewed, 387 mothers (44%) had ANC CD4 testing done, of whom 75 (19%) had a CD4 count < 200 cells/mm(3). Proportions of pairs fully, partially and non-compliant with guidelines were 38, 34 and 28%, respectively. A definitive infant HIV-infection status was determined in 578 infants (66%). The overall mother-to-child transmission (MTCT) rate was 5.1% [95% confidence interval (95%(CI): 3.8-6.9] and the MTCT rates for the fully, partially and non-compliant groups were 1.2% (95% CI: 0.4-3.3), 6.0% (95% CI: 3.7-9.5) and 9.5% (95% CI: 6.2-14.0; p<0.001). Factors associated with compliance were: have ANC, awareness of the mothers' HIV status before delivery, and having first ANC prior to 24 weeks gestation. Compliance with the 2006 national PMTCT guidelines was low, and the MTCT rates were high among non- and partially compliant mother-infant pairs. The simplified PMTCT guidellines introduced in 2010, might increase compliance with and improve outcomes for Thailand's PMTCT program.