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Background: In response to the 2015–2016 Zika virus (ZIKV) outbreak and the causal relationship established between maternal ZIKV infection and adverse infant outcomes, we conducted a cohort study to estimate the incidence of ZIKV infection in pregnancy and assess its impacts in women and infants. Methodology/Principal findings: From May 2018-January 2020, we prospectively followed pregnant women recruited from 134 participating hospitals in two non-adjacent provinces in northeastern Thailand. We collected demographic, clinical, and epidemiologic data and blood and urine at routine antenatal care visits until delivery. ZIKV infections were confirmed by real-time reverse transcriptase polymerase chain reaction (rRT-PCR). Specimens with confirmed ZIKV underwent whole genome sequencing. Among 3,312 women enrolled, 12 (0.36%) had ZIKV infections, of which two (17%) were detected at enrollment. Ten (83%, 3 in 2nd and 7 in 3rd trimester) ZIKV infections were detected during study follow-up, resulting in an infection rate of 0.15 per 1,000 person-weeks (95% CI: 0.07–0.28). The majority (11/12, 91.7%) of infections occurred in one province. Persistent ZIKV viremia (42 days) was found in only one woman. Six women with confirmed ZIKV infections were asymptomatic until delivery. Sequencing of 8 ZIKV isolates revealed all were of Asian lineage. All 12 ZIKV infected women gave birth to live, full-term infants; the only observed adverse birth outcome was low birth weight in one (8%) infant. Pregnancies in 3,300 ZIKV-rRT-PCR-negative women were complicated by 101 (3%) fetal deaths, of which 67 (66%) had miscarriages and 34 (34%) had stillbirths. There were no differences between adverse fetal or birth outcomes of live infants born to ZIKV-rRT-PCR-positive mothers compared to live infants born to ZIKV-rRT-PCR-negative mothers. Conclusions/Significance: Confirmed ZIKV infections occurred infrequently in this large pregnancy cohort and observed adverse maternal and birth outcomes did not differ between mothers with and without confirmed infections. Author summary: Zika virus (ZIKV) is an emerging infectious pathogen that was elevated to a Public Health Emergency of International Concern in 2016, due to its possible association with congenital microcephaly, a serious birth defect for infants. We launched a prospective cohort study of pregnant women to look for evidence of ZIKV infection during pregnancy. We enrolled participants in two provinces in northeastern Thailand during May 2018-January 2020. We found a low frequency of ZIKV infection (12/3312, 0.36% by rRT-PCR assay) during the study; two infections were detected at enrollment, while ten were detected later. Six of 12 ZIKV-confirmed women were asymptomatic throughout the study. Most (11/12, 92%) Zika cases occurred in one province. All 12 women with ZIKV delivered normal live births; only one infant had low birth weight and no infants had microcephaly. The eight ZIKV isolates available for whole genome sequencing were of the Asian lineage. At enrollment, the median Dengue virus IgG titer was significantly higher in ZIKV-confirmed than non-ZIKV-confirmed women. Identifying the factors associated with neonatal outcomes after ZIKV exposure in utero would be made easier with additional research studies. [ABSTRACT FROM AUTHOR]

Background: Pneumococcal colonization prevalence and colonization density, which has been associated with invasive disease, can offer insight into local pneumococcal ecology and help inform vaccine policy discussions. Methods: The Pneumonia Etiology Research for Child Health Project (PERCH), a multi-country case-control study, evaluated the etiology of hospitalized cases of severe and very severe pneumonia among children aged 1–59 months. The PERCH Thailand site enrolled children during January 2012–February 2014. We determined pneumococcal colonization prevalence and density, and serotype distribution of colonizing isolates. Results: We enrolled 224 severe/very severe pneumonia cases and 659 community controls in Thailand. Compared to controls, cases had lower colonization prevalence (54.5% vs. 62.5%, p = 0.12) and lower median colonization density (42.1 vs. 210.2 x 103 copies/mL, p <0.0001); 42% of cases had documented antibiotic pretreatment vs. 0.8% of controls. In no sub-group of assessed cases did pneumococcal colonization density exceed the median for controls, including cases with no prior antibiotics (63.9x103 copies/mL), with consolidation on chest x-ray (76.5x103 copies/mL) or with pneumococcus detected in whole blood by PCR (9.3x103 copies/mL). Serotype distribution was similar among cases and controls, and a high percentage of colonizing isolates from cases and controls were serotypes included in PCV10 (70.0% and 61.8%, respectively) and PCV13 (76.7% and 67.9%, respectively). Conclusions: Pneumococcal colonization is common among children aged <5 years in Thailand. However, colonization density was not higher among children with severe pneumonia compared to controls. These results can inform discussions about PCV introduction and provide baseline data to monitor PCV impact after introduction in Thailand. [ABSTRACT FROM AUTHOR]

Introduction: The prevalence of bacteremia caused by Gram negative non-fermentative (GNNF) bacteria has been increasing globally over the past decade. Many studies have investigated their epidemiology but focus on the common GNNF including Pseudomonas aeruginosa and Acinetobacter baumannii. Knowledge of the uncommon GNNF bacteremias is very limited. This study explores invasive bloodstream infection GNNF isolates that were initially unidentified after testing with standard microbiological techniques. All isolations were made during laboratory-based surveillance activities in two rural provinces of Thailand between 2006 and 2014. Methods: A subset of GNNF clinical isolates (204/947), not identified by standard manual biochemical methodologies were run on the BD Phoenix automated identification and susceptibility testing system. If an organism was not identified (12/204) DNA was extracted for whole genome sequencing (WGS) on a MiSeq platform and data analysis performed using 3 web-based platforms: Taxonomer, CGE KmerFinder and One Codex. Results: The BD Phoenix automated identification system recognized 92% (187/204) of the GNNF isolates, and because of their taxonomic complexity and high phenotypic similarity 37% (69/187) were only identified to the genus level. Five isolates grew too slowly for identification. Antimicrobial sensitivity (AST) data was not obtained for 93/187 (50%) identified isolates either because of their slow growth or their taxa were not in the AST database associated with the instrument. WGS identified the 12 remaining unknowns, four to genus level only. Conclusion: The GNNF bacteria are of increasing concern in the clinical setting, and our inability to identify these organisms and determine their AST profiles will impede treatment. Databases for automated identification systems and sequencing annotation need to be improved so that opportunistic organisms are better covered. [ABSTRACT FROM AUTHOR]

Background: Data on the burden of the 2009 influenza pandemic in Asia are limited. Influenza A(H1N1)pdm09 was first reported in Thailand in May 2009. We assessed incidence and epidemiology of influenza-associated hospitalizations during 2009-2010. Methods: We conducted active, population-based surveillance for hospitalized cases of acute lower respiratory infection (ALRI) in all 20 hospitals in two rural provinces. ALRI patients were sampled 1:2 for participation in an etiology study in which nasopharyngeal swabs were collected for influenza virus testing by PCR. Results :Of 7,207 patients tested, 902 (12.5%) were influenza-positive, including 190 (7.8%) of 2,436 children aged ,5 years; 86% were influenza A virus (46% A(H1N1)pdm09, 30% H3N2, 6.5% H1N1, 3.5% not subtyped) and 13% were influenza B virus. Cases of influenza A(H1N1)pdm09 first peaked in August 2009 when 17% of tested patients were positive. Subsequent peaks during 2009 and 2010 represented a mix of influenza A(H1N1)pdm09, H3N2, and influenza B viruses. The estimated annual incidence of hospitalized influenza cases was 136 per 100,000, highest in ages ,5 years (477 per 100,000) and .75 years (407 per 100,000). The incidence of influenza A(H1N1)pdm09 was 62 per 100,000 (214 per 100,000 in children, 5 years). Eleven influenza-infected patients required mechanical ventilation, and four patients died, all adults with influenza A(H1N1)pdm09 (1) or H3N2 (3). Conclusions: Influenza-associated hospitalization rates in Thailand during 2009-10 were substantial and exceeded rates described in western countries. Influenza A(H1N1)pdm09 predominated, but H3N2 also caused notable morbidity. Expanded influenza vaccination coverage could have considerable public health impact, especially in young children. [ABSTRACT FROM AUTHOR]

Background: We describe human rhinovirus (HRV) detections in SaKaeo province, Thailand. Methods: From September 1, 2003-August 31, 2005, we tested hospitalized patients with acute lower respiratory illness and outpatient controls without fever or respiratory symptoms for HRVs with polymerase chain reaction and molecularlytyped select HRVs. We compared HRV detection among hospitalized patients and controls and estimated enrollment adjusted incidence. Results: HRVs were detected in 315 (16%) of 1919 hospitalized patients and 27 (9.6%) of 280 controls. Children had the highest frequency of HRV detections (hospitalized: ,1 year: 29%, 1-4 year: 29%, ≥65 years: 9%; controls: ,1 year: 24%, 1-4 year: 14%, ≥65 years: 2.8%). Enrollment adjusted hospitalized HRV detection rates were highest among persons aged ,1 year (1038/100,000 persons/year), 1-4 years (457), and ≥65 years (71). All three HRV species were identified, HRV-A was the most common species in most age groups including children aged ,1 year (61%) and all adult age groups. HRV-C was the most common species in the 1-4 year (51%) and 5-19 year age groups (54%). Compared to controls, hospitalized adults (≥19 years) and children were more likely to have HRV detections (odds ratio [OR]: 4.8, 95% confidence interval [CI]: 1.5, 15.8; OR: 2.0, CI: 1.2, 3.3, respectively) and hospitalized children were more likely to have HRV-A (OR 1.7, CI: 0.8, 3.5) or HVR-C (OR 2.7, CI: 1.2, 5.9) detection. Conclusions: HRV rates were high among hospitalized children and the elderly but asymptomatic children also had substantial HRV detection. HRV (all species), and HRV-A and HRV-C detections were epidemiologically-associated with hospitalized illness. Treatment or prevention modalities effective against HRV could reduce hospitalizations due to HRV in Thailand. [ABSTRACT FROM AUTHOR]

Background: We describe the epidemiology of hospitalized RSV infections for all age groups from population-based surveillance in two rural provinces in Thailand. Methods: From September 1, 2003 through December 31, 2007, we enrolled hospitalized patients with acute lower respiratory tract illness, who had a chest radiograph ordered by the physician, from all hospitals in SaKaeo and Nakhom Phanom Provinces. We tested nasopharyngeal specimens for RSV with reverse transcriptase polymerase chain reaction (RT-PCR) assays and paired-sera from a subset of patients with IgG enzyme immunoassay. Rates were adjusted for enrollment. Results: Among 11,097 enrolled patients, 987 (8.9%) had RSV infection. Rates of hospitalized RSV infection overall (and radiographically-confirmed pneumonia) were highest among children aged <1 year: 1,067/100,000 (534/100,000 radiographically-confirmed pneumonia) and 1-4 year: 403/100,000 (222/100,000), but low among enrolled adults aged ≥65 years: 42/100,000. Age <1 year (adjusted odds ratio [aOR] = 13.2, 95% confidence interval [CI] 7.7, 22.5) and 1-4 year (aOR = 8.3, 95% CI 5.0, 13.9) were independent predictors of hospitalized RSV infection. Conclusions: The incidence of hospitalized RSV lower respiratory tract illness among children <5 years was high in rural Thailand. Efforts to prevent RSV infection could substantially reduce the pneumonia burden in children aged <5 years. [ABSTRACT FROM AUTHOR]

Background: In 2015, Singapore had the first and only reported foodborne outbreak of invasive disease caused by the group B Streptococcus (GBS; Streptococcus agalactiae). Disease, predominantly septic arthritis and meningitis, was associated with sequence type (ST)283, acquired from eating raw farmed freshwater fish. Although GBS sepsis is well-described in neonates and older adults with co-morbidities, this outbreak affected non-pregnant and younger adults with fewer co-morbidities, suggesting greater virulence. Before 2015 ST283 had only been reported from twenty humans in Hong Kong and two in France, and from one fish in Thailand. We hypothesised that ST283 was causing region-wide infection in Southeast Asia., Methodology/principal Findings: We performed a literature review, whole genome sequencing on 145 GBS isolates collected from six Southeast Asian countries, and phylogenetic analysis on 7,468 GBS sequences including 227 variants of ST283 from humans and animals. Although almost absent outside Asia, ST283 was found in all invasive Asian collections analysed, from 1995 to 2017. It accounted for 29/38 (76%) human isolates in Lao PDR, 102/139 (73%) in Thailand, 4/13 (31%) in Vietnam, and 167/739 (23%) in Singapore. ST283 and its variants were found in 62/62 (100%) tilapia from 14 outbreak sites in Malaysia and Vietnam, in seven fish species in Singapore markets, and a diseased frog in China., Conclusions: GBS ST283 is widespread in Southeast Asia, where it accounts for a large proportion of bacteraemic GBS, and causes disease and economic loss in aquaculture. If human ST283 is fishborne, as in the Singapore outbreak, then GBS sepsis in Thailand and Lao PDR is predominantly a foodborne disease. However, whether transmission is from aquaculture to humans, or vice versa, or involves an unidentified reservoir remains unknown. Creation of cross-border collaborations in human and animal health are needed to complete the epidemiological picture., Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: SLC and TB are named applicants on a patent for the ST83-specific PCR test used in this study.