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While many factors contribute to mother-to-child transmission (MTCT) of HIV-1, maternal plasma HIV-1 RNA viral load (RNA-VL) has been consistently found as the main risk factor, including when antiretroviral prophylaxis was used to prevent MTCT. However the predictive value of RNA-VL is poor. A recent study of HIV-1–positive pregnant women who did not receive antiretroviral prophylaxis reported an association between HIV-1 DNA viral load (DNA-VL) and MTCT that was stronger than the association between RNA-VL and MTCT. We sought to determine if HIV-1 DNA-VL was independently associated with MTCT of HIV in a population of women who received zidovudine prophylaxis during pregnancy and whose infants received zidovudine after birth. Patients were 33 non-breastfeeding transmitting (TR) and 33 nontransmitting mothers (NTR) from Perinatal HIV Prevention Trial (PHPT-1), a multicenter clinical trial conducted in Thailand comparing zidovudine prophylaxis durations to prevent MTCT. TR and NTR mothers were matched according to baseline RNA-VL. Maternal peripheral blood mononuclear cell (PBMC)-associated HIV-1 DNA was extracted from whole blood, and DNA-VL was established by quantitative real-time polymerase chain reaction. We found that TR had a significantly higher cell-associated HIV-1 DNA viral load than did NTR. Median TR DNA-VL was 2.54 log10 copies per microgram PBMC DNA, while it was 2.28 log10 copies per microgram PBMC DNA in NTR (Wilcoxon p = 0.02). In summary, HIV-1 DNA viral load was associated with MTCT in a population of women who received antiretroviral prophylaxis during pregnancy, independently from RNA viral load. [ABSTRACT FROM AUTHOR]

Background Previous studies have suggested that mother-to-child transmission of HIV-1 is often characterized by acquisition of a homogeneous viral quasispecies in the infant, suggestive of a genetic bottleneck. In this study, we have analyzed the molecular characteristics of transmitted HIV-1 viruses in a homogeneous population infected by CRF01_AE variants in Thailand. Materials and methods Seventeen mother-child pairs were studied. The infants were not breastfed. Six infants were infected in utero and 11 infants were infected intrapartum. The env sequences covering the entire gp120 were amplified from both the proviral DNA of maternal PBMC collected at delivery and the plasma viral RNA at first positive time point of infants. The amplified products were cloned and sequenced. A total of 353 clones were available for analysis. Results Phylogenetic analysis indicated 2 patterns of transmission: 14 mothers transmitted a single variant and 3 mothers transmitted multiple variants to their infants. The mean genetic distance of viruses from the mothers was significantly higher than those from the infants (2.7% vs. 0.6%; P<0.01), but without any difference according to timing of transmission, either in utero or intrapartum. The length of gp120 and number of potential N-linked glycosylation sites (PNGS) were similar in both the entire gp120 and individual regions of gp120 of all motherchild pairs. However, our data indicate that 4 PNGS positions (N241, N301, N354, and N384) that appeared conserved in all infant variants but were irregularly present in the mothers might be associated to a selective advantage. In addition, we report the first case to our knowledge of transmission to an infant of a recombinant virus issued from variants from his mother. Conclusions Our results provide additional evidence that despite a complex viral population in the mother, only viruses of a restricted subset are transmitted to the infant, independently of the timing of transmission, in utero or intrapartum. We did not find that shorter gp120 or fewer PNGS were characteristics of viruses transmitted from mother to infant, as it was suggested for sexually transmitted viruses at least for a few subtypes. Four PNGS were selected for transmitted viruses, supporting the role of the "glycan shield" of the HIV-1 envelope in conferring a selective advantage. [ABSTRACT FROM AUTHOR]

This study aimed to identify the bacterial etiology of empyema thoracis or parapneumonic pleural effusions in Thai children, with a focus on pneumococcus. This hospital-based, descriptive study included children aged < or = 16 years, diagnosed with empyema thoracis or parapneumonic pleural effusion, from whom a pleural fluid (PF) sample was taken between January 2008 and November 2009. PF and blood samples were cultured and PF samples were also tested by polymerase chain reaction (PCR) to assess whether evidence of an infection might be identified among culture-negative samples. Serotyping of Streptococcus pneumoniae-positive samples was performed by molecular techniques and Quellung reaction. In this study, 29 children with empyema thoracis and 42 children with parapneumonic pleural effusion were enrolled. Potentially pathogenic bacteria were cultured in 13/71 samples at local or central laboratories; the most common bacteria were Staphylococcus aureus (8 children) and S. pneumoniae (2 children). Molecular techniques detected one or more targeted respiratory pathogens in 18/71 PF samples. S. pneumoniae and Haemophilus influenzae were identified by PCR in 13 and 6 children, respectively; PCR for S. aureus was not performed. The pneumococcal serotypes identified were 1, 3, 5, 6A/B, 9A/V, 14, 15A, 19F and 23A. This study shows that among Thai children with empyema thoracis and parapneumonic pleural effusions, S. aureus and S. pneumoniae were the most common pathogens identified by culture and PCR, respectively. These findings confirmed that molecular techniques are more sensitive for identification of S. pneumoniae and H. influenzae and enhance detection of important bacterial causes of empyema.

The immunogenicity and safety of a pediatric dose of a virosomal hepatitis A vaccine (Epaxal®) was evaluated in a group of 45 Thai children with human immunodeficiency virus (HIV) infection, age 2-16 years. Vaccines were administered at 0 and 6 months. Anti-HAV antibody titers were measured at baseline (before injection) 1 and 7 months after primary vaccination. The prevalence of HAV protective antibody in 45 Thai HIV-infected children was 13.6%. The seroprotection rate was 71% at 1 month and 100% at 7 months. The booster dose increased geometric mean concentration (GMC) from 106.5 mIU/ml to 3486.1 mIU/ml. Higher CD4 lymphocyte counts at enrollment was a predictive factor for HAV antibody response. Both doses of Epaxal® were well tolerated. These preliminary data suggest that a pediatric dose of Epaxal® is an effective hepatitis A vaccine for HIV-infected children and should be considered for implementation on a larger scale in the pediatric HIV population., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Three patients were admitted to Hat Yai Hospital, Songkhla Thailand with hemoptysis. They were previously healthy children aged 6, 13, and 14 years old who had attended schools in which outbreaks of influenza had occurred. They all had a history of fever, rhinorrhea, and severe cough accompanied by hemoptysis. Two developed hemoptysis on Day 3 and the third on Day 6 of illness, with one of them displaying massive hemoptysis. Chest radiographs were compatible with viral pneumonia in two cases and the third case was unremarkable. Coagulation profiles in the severe case were carried out and were normal. All the patients responded very well to treatment with oseltamivir and did not require intubation. Their subsequent nasopharyngeal swabs were positive for human pandemic influenza A H1N1 by real-time reverse transcription-polymerase chain reaction (RT-PCR), and their sputum for acid-fast bacilli and tuberculin skin tests were negative.

Objective: Safety and reactogenicity of a new heptavalent DTPw-HBV/Hib-MenAC (diphtheria, tetanus, whole cell pertussis-hepatitis B virus/Haemophilus influenzae type b-Neisseria meningitidis serogroups A and C) vaccine was compared with a widely used pentavalent DTPw-HBV/Hib vaccine., Methods: Three phase III randomized studies comparable in design and methodology, in which healthy infants received DTPw-HBV/Hib-MenAC (N=1334) or DTPw-HBV/Hib (N=446) at 2, 4, and 6 months, were pooled for analysis. Solicited symptoms were recorded for 4 days, and unsolicited adverse events for 31 days after each dose. Serious adverse events (SAEs) were recorded throughout the studies., Results: There were no significant differences between the two groups in the proportion of subjects with fever >39.5 degrees C or >40.0 degrees C (p<0.005). Compared to group DTPw-HBV/Hib, a significantly higher percentage of subjects in group DTPw-HBV/Hib-MenAC reported fever >39 degrees C (21.2% vs. 14.8%, p=0.004). Fever subsided quickly, did not lead to differences in attendance to medical services and did not increase from dose to dose. Sixty-seven SAEs were reported, 56/1334 (4.2%) in group DTPw-HBV/Hib-MenAC and 11/446 (2.5%) in the DTPw-HBV/Hib group., Conclusion: Overall, the heptavalent and pentavalent vaccines had similar safety profiles. The difference observed in percentage of subjects with fever >39 degrees C did not lead to differences in medically attended visits for fever.

A trial to compare the reactogenicity and immunogenicity of a reduced antigen content diphtheria-tetanus-acellular pertussis (dTpa) vaccine with diphtheria-tetanus-whole-cell pertussis (DTPw) vaccine was conducted in Thailand. Three hundred and thirty children aged 4-6 years, primed with four doses of DTPw, received a single injection of either dTpa or DTPw. There was a significantly lower incidence of local and general reactions following dTpa than DTPw (P<0.001). One month after vaccination, 99.4 and 100% of all subjects had protective anti-diphtheria and -tetanus titers, respectively. The vaccine response rate to pertussis antigens was similar in both groups, with 96.9% versus 92.5% for anti-pertussis toxin (PT), 96.9% versus 97.5% for anti-filamentous hemagglutinin (FHA) and 95.1% versus 90.8% for anti-pertactin (PRN) in the dTpa and DTPw groups, respectively. For anti-BPT, the vaccine response in the dTpa group was 29.6% versus 94.4% for DTPw. In conclusion, the dTpa vaccine was as immunogenic and significantly better tolerated than DTPw. The new dTpa vaccine could improve coverage for routine booster vaccination in children and provide a good replacement for DTP vaccines at 4-6 years of age.