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HIV/AIDS is a major public health problem worldwide, especially in developing countries. The development of a safe and effective HIV vaccine is central to stopping the epidemic and would be a great public health tool. The AIDS Vaccine for Asia Network (AVAN) is a group of concerned investigators committed to assisting regional and global HIV vaccine efforts. AVAN's focus on improving the coordination and harmonization of research, ethical reviews, clinical trial capacity, regulatory frameworks, vaccine manufacturing, community participation, and government advocacy could help accelerate HIV vaccine efforts in the region. At a meeting in November 2010, researchers from various countries in Asia presented their progress in HIV vaccine research and development. Six working groups discussed the current status, gaps and methods to strengthen capacity and infrastructure in various areas related to AIDS vaccine research and development. These discussions led to the development of prioritized action plans for the next 5 years. This report describes the gaps and challenges HIV vaccine research faces in the region and recommends improvement and standardization of facilities, and coordination and harmonization of all activities related to AIDS vaccine research and development, including possible technology transfer when a vaccine becomes available.

Background: A prime-boost vaccination regimen with ALVAC-HIV (vCP1521) administered intramuscularly at 0, 4, 12, and 24 weeks and gp120 AIDSVAX B/E at 12 and 24 weeks demonstrated modest efficacy of 31.2% for prevention of HIV acquisition in HIV-uninfected adults participating in a community-based efficacy trial in Thailand., Methodology/principal Findings: Reactogenicity was recorded for 3 days following vaccination. Adverse events were monitored every 6 months for 3.5 years, during which pregnancy outcomes were recorded. Of the 16,402 volunteers, 69% of the participants reported an adverse event any time after the first dose. Only 32.9% experienced an AE within 30 days following any vaccination. Overall adverse event rates and attribution of relatedness did not differ between groups. The frequency of serious adverse events was similar in vaccine (14.3%) and placebo (14.9%) recipients (p = 0.33). None of the 160 deaths (85 in vaccine and 75 in placebo recipients, p = 0.43) was assessed as related to vaccine. The most common cause of death was trauma or traffic accident. Approximately 30% of female participants reported a pregnancy during the study. Abnormal pregnancy outcomes were experienced in 17.1% of vaccine and 14.6% (p = 0.13) of placebo recipients. When the conception occurred within 3 months (estimated) of a vaccination, the majority of these abnormal outcomes were spontaneous or elective abortions among 22.2% and 15.3% of vaccine and placebo pregnant recipients, respectively (p = 0.08). Local reactions occurred in 88.0% of vaccine and 61.0% of placebo recipients (p<0.001) and were more frequent after ALVAC-HIV than AIDSVAX B/E vaccination. Systemic reactions were more frequent in vaccine than placebo recipients (77.2% vs. 59.8%, p<0.001). Local and systemic reactions were mostly mild to moderate, resolving within 3 days., Conclusions/significance: The ALVAC-HIV and AIDSVAX B/E vaccine regimen was found to be safe, well tolerated and suitable for potential large-scale use in Thailand., Trial Registration: ClinicalTrials.govNCT00223080.

The HIV/AIDS pandemic continues to spread and an AIDS vaccine is urgently needed. Regional alliances and international collaborations can foster the development and evaluation of the next generation of AIDS vaccine candidates. The importance of coordinating and harmonizing efforts across regional alliances has become abundantly clear. We recently formed the AIDS Vaccine for Asia Network (AVAN) to help facilitate the development of a regional AIDS vaccine strategy that accelerates research and development of an AIDS vaccine through government advocacy, improved coordination, and harmonization of research; develops clinical trial and manufacturing capacity; supports ethical and regulatory frameworks; and ensures community participation.

Purpose of Review: An effective HIV vaccine is a global health priority. We describe lessons learned from four HIV vaccine trials that failed to demonstrate efficacy and one that showed modest protection as a pathway forward., Recent Findings: The Merck Ad5 phase IIb T-cell vaccine failed to show efficacy and might have increased the risk of HIV acquisition in men who have sex with men. Although VaxGen gp120 alone was not efficacious in groups at high risk for HIV-1 infection, the RV144 ALVAC prime and gp120 boost regimen showed 31% efficacy in low-incidence heterosexuals. All trials demonstrated the limitations of available laboratory and animal models to assess relevant vaccine-induced immune responses and predict clinical trial outcome. Analysis of innate and adaptive responses induced in RV144 will guide future trial design., Summary: Future HIV vaccine trials should define the RV144 immune responses relevant to protection, improve durability and level of protection, and assess efficacy in diverse risk groups. New strategies examining heterologous vector prime-boost, universal inserts, replicating vectors, and novel protein or adjuvant immunogens should be explored to induce T-cell and antibody responses. HIV vaccine development requires innovative ideas and a sustained long-term commitment of scientists, governments, and the community.

Acute bacterial meningitis is an important cause of morbidity and mortality in children. To estimate the incidence of meningitis caused by all types of bacteria in Thai children under five years of age, data were collected using a rapid assessment tool (RAT) and analyzed. Clinical and laboratory data from suspected meningitis cases for a one-year period were retrospectively collected from 5 selected catchment areas located in the 4 regions of the country. Adjusted incidences of confirmed bacterial meningitis were calculated based on laboratory quality and lumbar puncture rates. Seventy-five suspected meningitis cases were identified among 305,023 children under age five in the catchment areas, with an unadjusted incidence of 24.6 per 100,000. Of these, 66.2, 55.9, and 33.8% were unconfirmed bacterial, purulent, and confirmed bacterial meningitis cases, respectively. Among the confirmed bacterial meningitis cases, 39.1, 26.1, 21.7 and 13.0% were caused by Haemophilus influenzae type B, gram-positive cocci, gram-negative bacilli, and Neisseria meningitidis, respectively. After adjusting based on the RAT application, the incidence of confirmed bacterial meningitis was about double that of the unadjusted incidence. This study gives an interval of possible incidences of bacterial meningitis in children under age five, which is between the unadjusted (low estimate) and adjusted (high estimate) incidences.

There are limited prospective data for Haemophilus influenzae type b (Hib) disease in Asia, where some countries are considering vaccine introduction. A prospective population-based study was conducted to measure the incidence of Hib meningitis in children in two northern provinces of Thailand. Children <5 years with symptoms consistent with bacterial meningitis were enrolled in the study if inclusion criteria were met. The study enrolled 598 children with clinical meningitis, 76% of whom received lumbar puncture. The rate of probable bacterial meningitis was 26.6/100,000 children <5 years per year. There were four cases of laboratory confirmed Hib meningitis (rate 3.8/100,000 children <5 years per year). These findings suggest a relatively low incidence of Hib meningitis. However, additional data from studies of pneumonia are needed to define the Hib disease burden in Thailand.

The summary report of AIDS cases in Thailand, as of 31 July 1996, was reviewed for the information on male-to female sex-ratio. The ratios were recalculated for different risk-factors and for different age-groups annually and cumulatively. The male-to-female ratios calculated for annual case reports are lower than the cumulative number. This finding demonstrates the earlier detection of change in risk behaviour among the general population by the sex-ratio from annual case reports, compared to the ratio from the cumulative number of cases. Among different age-groups, the older age shows the highest male-to-female ratio. The ratio among sexually active age-group (15-49 years of age) is declining during the most recent year. These changes confirm the present pattern of AIDS epidemic in Thailand, the fourth wave among females, followed by the last wave-pediatric AIDS.

We examined the risk factors for heterosexual transmission of HIV in a case-control study of couples in Thailand. 90 HIV-positive men and their regular sex partners were enrolled at the immune clinic, Chulalongkorn Hospital, where 92% of male index cases had HIV-1 serotype A (subtype E). Most index cases had acquired HIV through sexual intercourse. 95 couples were enrolled at 15 detoxification clinics, where 79% of them had HIV-1 serotype B (subtype B). Most men had acquired HIV through injecting drug use (IDU).