Stigma toward homosexuality plays an important role in the increased risk of acquiring or transmitting HIV among men who have sex with men (MSM). This study describes associations between three dimensions of homosexuality-related stigma (enacted, perceived and internalized) and HIV risk behaviors among HIV-negative MSM in Hanoi, Vietnam. A total of 1675 HIV-negative MSM were recruited from the baseline of a cohort study from 2017 to 2019 through respondent-driven, time-location and internet-based sampling strategies. Stigma was measured by a locally validated instrument, with a higher score indicated a higher level of stigma (from 1 to 4). Enacted stigma (mean = 2.10), perceived stigma (mean = 2.62) and internalized stigma (mean = 2.55) were found. About 25% of participants reported group sex and 6.3% reported drug use before or during group sex in the last 6 months. Enacted stigma was significantly associated with group sex (adjusted OR = 1.48; 95% CI 1.20-1.84) and drug use before or during group sex (adjusted OR = 1.68; 95% CI 1.19-2.36). Internalized stigma was significantly associated with group sex (adjusted OR = 1.27; 95% CI 1.05-1.53) and drug use before or during group sex (adjusted OR = 1.44; 95% CI 1.04-1.99). The results highlight the need for multifaced interventions at a multiple socio-ecological levels to reduce stigma toward homosexuality.

BACKGROUND: Infection by Cryptococcus gattii can lead to pulmonary or central nervous system (CNS) disease, or both. Whether site of infection and disease severity are associated with C. gattii species and lineages or with certain underlying medical conditions, or both is unclear. We conducted a retrospective cohort study to identify factors associated with site of infection and mortality among C. gattii cases. METHODS: We extracted data on 258 C. gattii cases from Australia, Canada and the United States reported from 1999 to 2011. We conducted unadjusted and multivariable logistic regression analyses to evaluate factors associated with site of infection and C. gattii mortality among hospitalized cases (N=218). RESULTS: Hospitalized C. gattii cases with CNS and other extrapulmonary disease were younger, more likely to reside in Australia and be infected with VGI lineage but less likely to have comorbidities and die as compared to pulmonary cases. The odds of having CNS and/or other extrapulmonary disease were 9 times higher in cases with VGI infection (aOR=9.21, 95%CI=3.28-25.89). Age >70 years (aOR=6.69, 95%CI=2.44-18.30), chronic lung disease (aOR=2.62, 95%CI=1.05-6.51) and an immunocompromised status (aOR=2.08, 95%CI=1.05-6.51) were associated with higher odds of C. gattii mortality. CONCLUSIONS: Among hospitalized cases, C. gattii species and lineage are associated with site of infection but not with the risk of death, whereas older age and comorbidities increase the risk of death.

BACKGROUND: HIV drug resistance can reduce the effectiveness of antiretroviral drugs in preventing morbidity and mortality, limit options for treatment, and prevention. Our study aimed to assess HIV-1 subtypes and HIV drug resistance among key populations in HIV Sentinel Surveillance Plus Behavior in 2018 and 2020. METHODS: One-stage venue-based cluster sampling was used to recruit participants at hotspots identified for men who have sex with men (MSM) in 7 provinces and sexual minority females and female sex workers (FSW) in 13 provinces. Participants completed a standard questionnaire about risk and preventive behaviors, and antiretroviral therapy history, and provided intravenous blood for HIV testing. HIV drug resistance testing was conducted on HIV-positive samples with viral load >1000 copies/mL. RESULTS: A total of 185 of 435 (42.5%) HIV-positive samples had viral load ≥1000 copies/mL, of which 130 of 136 from MSM and 26 of 49 from FSW were successfully sequenced. Six HIV-1 subtypes were detected (CRF01_AE, A, CRF07/08_BC, B, C, CRF25_cpx), with CRF01_AE (82.7%, 129/156) the most common. Drug resistance mutations were detected in 16.7% of participants overall (26/156), in 15.4% (20/130) of MSM, and in 23.1% (6/26) of FSW. Mutations associated with resistance to non-nucleoside reverse transcriptase inhibitor (NNRTI) were the most frequently detected (73.1%, 19/26). The high level of resistance was presented in NNRTI and nucleoside reverse transcriptase inhibitors classes. There are 10 major resistance mutations detected with nucleoside reverse transcriptase inhibitors (M184VI-25.0%, K65KR-50.0%, Y115F-25%), NNRTI (K103N-21.1%, E138A-10.5%, V106M-5.3%, K101E-5.3%, G190A-5.3%), protease inhibitors (L33F-40.0%, M46L-20.0%). CONCLUSIONS: Vietnam's HIV Sentinel Surveillance Plus system identified an emerging strain of HIV-1 and mutations associated with resistance to multiple drug classes among MSM and FSW.

Oral pre-exposure prophylaxis (PrEP) reduces HIV acquisition risk from sex by 99% and from injection drug use by ≥74% when used as recommended. The Joint United Nations Programme on HIV/AIDS (UNAIDS) has set a goal of 21.2 million persons using (initiating or continuing) PrEP globally in 2025. In 2016, CDC, with the U.S. President's Emergency Plan for AIDS Relief, joined ministries of health to implement PrEP globally. PrEP is beneficial for persons at substantial risk for acquiring HIV, including but not limited to key populations, which include female sex workers, men who have sex with men, persons in prisons and other enclosed settings, persons who inject drugs, and transgender persons. Annual country targets were used to guide scale-up. In 2023, CDC supported 856,816 PrEP initiations, which represents nearly one quarter of the 3.5 million persons globally who either initiated or continued PrEP that year. During 2017-2023, CDC supported PrEP initiations for 2,278,743 persons, 96.0% of whom were in sub-Saharan Africa. More than one half (64.0%) were female and 44.9% were aged 15-24 years. Overall, CDC achieved 118.7% of its PrEP initiation targets for the 7-year period. Among PrEP initiations for key populations, the majority in sub-Saharan Africa were female sex workers, whereas in Southeast Asia, Eurasia, and the Americas, the majority were men who have sex with men. Continued rapid scale-up is needed to meet the UNAIDS goal to end HIV as a public health threat.

BACKGROUND: Streptococcus pneumoniae (S. pneumoniae), Haemophilus influenzae (H. influenzae), and Neisseria meningitidis (N. meningitidis) are leading causes of childhood bacterial meningitis and preventable by vaccines. The aim of this hospital-based sentinel surveillance is to describe the epidemiological characteristics of pneumococcal meningitis, including disease burden, and to provide baseline data on pneumococcal serotype distribution to support decision making for pneumococcal conjugate vaccine (PCV) introduction in Vietnam. METHODS: Surveillance for probable bacterial meningitis in children 1-59 months of age is conducted in three tertiary level pediatric hospitals: one in Hanoi and two in Ho Chi Minh City. Cerebrospinal fluid (CSF) specimens were collected via lumbar puncture from children with suspected meningitis. Specimens were transferred immediately to the laboratory department of the respective hospital for cytology, biochemistry, and microbiology testing, including culture. PCR testing was conducted on CSF specimens for bacterial detection (S. pneumoniae, H. influenzae, and N. meningitidis) and pneumococcal serotyping. RESULTS: During 2015-2018, a total of 1,803 children with probable bacterial meningitis were detected; 1,780 had CSF specimens available for testing. Of 245 laboratory-confirmed positive cases, the majority were caused by S. pneumoniae (229,93.5%). Of those with S. pneumoniae detected, over 70% were caused by serotypes included in currently available PCV products; serotypes 6 A/6B (27.1%), 14 (19.7%), and 23 F (16.2%) were the most common serotypes. Children with laboratory-confirmed pneumococcal meningitis were more likely to live in Hanoi (p < 0.0001) and children 12-23 months of age were at greater odds (OR = 1.65, 95% CI: 1.11, 2.43; p = 0.006) of having confirmed pneumococcal meningitis compared to children < 12 months of age when compared to those without laboratory-confirmed bacterial meningitis. Additionally, children with confirmed pneumococcal meningitis were more likely to exhibit signs and symptoms consistent with clinical meningitis compared to negative laboratory-confirmed meningitis cases (p < 0.0001) and had a greater odds of death (OR = 6.18, 95% CI: 2.98, 12.86; p < 0.0001). CONCLUSIONS: Pneumococcal meningitis contributes to a large burden of bacterial meningitis in Vietnamese children. A large proportion are caused by serotypes covered by PCVs currently available. Introduction of PCV into the routine immunization program could reduce the burden of pneumococcal meningitis in Viet Nam.

INTRODUCTION: An error grid compares measured versus reference glucose concentrations to assign clinical risk values to observed errors. Widely used error grids for blood glucose monitors (BGMs) have limited value because they do not also reflect clinical accuracy of continuous glucose monitors (CGMs). METHODS: Diabetes Technology Society (DTS) convened 89 international experts in glucose monitoring to (1) smooth the borders of the Surveillance Error Grid (SEG) zones and create a user-friendly tool-the DTS Error Grid; (2) define five risk zones of clinical point accuracy (A-E) to be identical for BGMs and CGMs; (3) determine a relationship between DTS Error Grid percent in Zone A and mean absolute relative difference (MARD) from analyzing 22 BGM and nine CGM accuracy studies; and (4) create trend risk categories (1-5) for CGM trend accuracy. RESULTS: The DTS Error Grid for point accuracy contains five risk zones (A-E) with straight-line borders that can be applied to both BGM and CGM accuracy data. In a data set combining point accuracy data from 18 BGMs, 2.6% of total data pairs equally moved from Zones A to B and vice versa (SEG compared with DTS Error Grid). For every 1% increase in percent data in Zone A, the MARD decreased by approximately 0.33%. We also created a DTS Trend Accuracy Matrix with five trend risk categories (1-5) for CGM-reported trend indicators compared with reference trends calculated from reference glucose. CONCLUSION: The DTS Error Grid combines contemporary clinician input regarding clinical point accuracy for BGMs and CGMs. The DTS Trend Accuracy Matrix assesses accuracy of CGM trend indicators.

INTRODUCTION: We assessed trends in HIV and syphilis prevalence, HIV incidence, related risk factors, and preventive behaviors among men who have sex with men (MSM) in Vietnam from 2015 to 2020. METHODS: Data originated from the HIV Sentinel Surveillance Plus system, which sampled MSM at venues and hotspots in seven of Vietnam's 63 provinces in 2015, 2016, 2018, and 2020 (N = 1100-1445 per year; ∼150-300 per province per year). RESULTS: HIV prevalence estimates increased from 6.6% (95% CI 4.5-9.6) in 2015 to 13.8% (95% CI 10.5-18.2, p = .001 for trend) in 2020 overall, and separately in An Giang, Can Tho, Hai Phong, and Khanh Hoa provinces but not in Ho Chi Minh City, Hanoi, or Kien Giang. Syphilis prevalence increased from 2.7% (95% CI 1.4-5.1) in 2015 to 12.6% (95% CI 8.7-18.0) in 2020 overall (p < .001 for trend), and separately in An Giang, Can Tho, and Hai Phong provinces but not in Ho Chi Minh City or Kien Giang. We calculated time-at-risk from first anal sex to first HIV-positive or last HIV-negative test to estimate HIV incidence. Estimated HIV incidence suggested increasing rates of seroconversion from 1.36 per 100 person-years experienced by participants in 2015 to 2.61 per 100 person-years among participants in 2020 (hazard ratio per year 1.13, 95% CI 1.08-1.18, p < .001). There was a statistically significant increase in HIV testing, STI testing, and receipt of free condoms over the period (p < .05 for trend), and a statistically significant decrease in amphetamine use (p = .043 for trend). CONCLUSIONS: Despite prevention efforts and improvements in some risk indicators, consecutive cross-sectional sampling results provide evidence of increasing incidence of HIV and syphilis among MSM in Vietnam, especially outside the major cities. Aggressive HIV prevention and treatment services can be expanded while conducting deeper investigations into the causes of these increases.

BACKGROUND: The effects of organochlorine pesticide (OCP) exposure on the development of human papillary thyroid cancer (PTC) are not well understood. A nested case-control study was conducted with data from the U.S. Department of Defense Serum Repository (DoDSR) cohort between 2000 and 2013 to assess associations of individual OCPs serum concentrations with PTC risk. METHODS: This study included 742 histologically confirmed PTC cases (341 females, 401 males) and 742 individually-matched controls with pre-diagnostic serum samples selected from the DoDSR. Associations between categories of lipid-corrected serum concentrations of seven OCPs and PTC risk were evaluated for classical PTC and follicular PTC using conditional logistic regression, adjusted for body mass index category and military branch to compute odds ratios (OR) and 95% confidence intervals (CIs). Effect modification by sex, birth cohort, and race was examined. RESULTS: There was no evidence of associations between most of the OCPs and PTC, overall or stratified by histological subtype. Overall, there was no evidence of an association between hexachlorobenzene (HCB) and PTC, but stratified by histological subtype HCB was associated with significantly increased risk of classical PTC (third tertile above the limit of detection (LOD) vs. <LOD, OR = 1.61, 95% CI, 1.09, 2.38; p for trend = 0.05) and significantly decreased risk of follicular variant PTC (third tertile above the limit of detection (LOD) vs. <LOD, OR = 0.38, 95% CI, 0.16, 0.91; p for trend = 0.04). Further stratified by sex, risk of classical PTC was higher for females (third tertile above LOD vs. <LOD, OR = 2.23, 95% CI: 1.23, 4.06; p-trend = 0.02) than for males (OR = 1.22, 95%CI: 0.72-2.08; p-trend = 0.56), though the test for interaction by sex was not statistically significant (p-interaction = 0.30). Similarly, β-hexachlorocyclohexane (β-HCCH) was associated with a higher risk for classical PTC for women with concentrations ≥LOD versus <LOD (OR = 1.76, 95% CI: 1.07, 2.89), while the effects were null for men. There were no consistent trends when stratified by race or birth year.  CONCLUSIONS: The U.S. Environmental Protection Agency has classified HCB and other OCPs we studied here as probable human carcinogens. Our findings of increased risks for classical PTC associated with increased concentrations of HCB and β-HCCH, which were stronger among females, should be replicated in future studies of other populations.

Single-pollutant methods to evaluate associations between endocrine disrupting chemicals (EDCs) and thyroid cancer risk may not reflect realistic human exposures. Therefore, we evaluated associations between exposure to a mixture of 18 EDCs, including polychlorinated biphenyls (PCBs), brominated flame retardants, and organochlorine pesticides, and risk of papillary thyroid cancer (PTC), the most common thyroid cancer histological subtype. We conducted a nested case-control study among U.S. military servicemembers of 652 histologically-confirmed PTC cases diagnosed between 2000 and 2013 and 652 controls, matched on birth year, sex, race/ethnicity, military component (active duty/reserve), and serum sample timing. We estimated mixture odds ratios (OR), 95% confidence intervals (95% CI), and standard errors (SE) for associations between pre-diagnostic serum EDC mixture concentrations, overall PTC risk, and risk of histological subtypes of PTC (classical, follicular), adjusted for body mass index and military branch, using quantile g-computation. Additionally, we identified relative contributions of individual mixture components to PTC risk, represented by positive and negative weights (w). A one-quartile increase in the serum mixture concentration was associated with a non-statistically significant increase in overall PTC risk (OR = 1.19; 95% CI = 0.91, 1.56; SE = 0.14). Stratified by histological subtype and race (White, Black), a one-quartile increase in the mixture was associated with increased classical PTC risk among those of White race (OR = 1.59; 95% CI = 1.06, 2.40; SE = 0.21), but not of Black race (OR = 0.95; 95% CI = 0.34, 2.68; SE = 0.53). PCBs 180, 199, and 118 had the greatest positive weights driving this association among those of White race (w = 0.312, 0.255, and 0.119, respectively). Findings suggest that exposure to an EDC mixture may be associated with increased classical PTC risk. These findings warrant further investigation in other study populations to better understand PTC risk by histological subtype and race.

Vaccine development against hepatitis C virus (HCV) is hindered by poor understanding of factors defining cross-immunoreactivity among heterogeneous epitopes. Using synthetic peptides and mouse immunization as a model, we conducted a quantitative analysis of cross-immunoreactivity among variants of the HCV hypervariable region 1 (HVR1). Analysis of 26,883 immunological reactions among pairs of peptides showed that the distribution of cross-immunoreactivity among HVR1 variants was skewed, with antibodies against a few variants reacting with all tested peptides. The HVR1 cross-immunoreactivity was accurately modeled based on amino acid sequence alone. The tested peptides were mapped in the HVR1 sequence space, which was visualized as a network of 11,319 sequences. The HVR1 variants with a greater network centrality showed a broader cross-immunoreactivity. The entire sequence space is explored by each HCV genotype and subtype. These findings indicate that HVR1 antigenic diversity is extensively convergent and effectively limited, suggesting significant implications for vaccine development.

BACKGROUND: Highly pathogenic avian influenza A(H5) human infections are a global concern, with many A(H5) human cases detected in Vietnam, including a case in October 2022. Using avian influenza virus surveillance from March 2017-September 2022, we described the percent of pooled samples that were positive for avian influenza A, A(H5), A(H5N1), A(H5N6), and A(H5N8) viruses in live bird markets (LBMs) in Vietnam. METHODS: Monthly at each LBM, 30 poultry oropharyngeal swab specimens and five environmental samples were collected. Samples were pooled in groups of five and tested for influenza A, A(H5), A(H5N1), A(H5N6), and A(H5N8) viruses by real-time reverse-transcription polymerase chain reaction. Trends in the percent of pooled samples that were positive for avian influenza were summarized by LBM characteristics and time and compared with the number of passively detected avian influenza outbreaks using Spearman's rank correlation. RESULTS: A total of 25,774 pooled samples were collected through active surveillance at 167 LBMs in 24 provinces; 36.9% of pooled samples were positive for influenza A, 3.6% A(H5), 1.9% A(H5N1), 1.1% A(H5N6), and 0.2% A(H5N8). Influenza A(H5) viruses were identified January-December and at least once in 91.7% of sampled provinces. In 246 A(H5) outbreaks in poultry; 20.3% were influenza A(H5N1), 60.2% A(H5N6), and 19.5% A(H5N8); outbreaks did not correlate with active surveillance. CONCLUSIONS: In Vietnam, influenza A(H5) viruses were detected by active surveillance in LBMs year-round and in most provinces sampled. In addition to outbreak reporting, active surveillance for A(H5) viruses in settings with high potential for animal-to-human spillover can provide situational awareness.

To develop an appropriate programmatic response to the concentrated HIV epidemic, program managers require reliable estimates of the sizes of the key populations. This study attempts to estimate the population size of people who inject drugs (PWID) in Thai Nguyen-a province in the northern part of Vietnam. Two source capture-recapture population size estimates were calculated using data from two respondent driven sampling survey rounds conducted in 5 selected districts from May to August 2019. The population size of the PWID was calculated based on the number of PWID recruited in each survey and 'recaptured' during the first and the second survey. Additionally, personal network size data collected in the RDS was used to measure the population of PWID using the Successive Sampling Population Size Estimate (SS-PSE) method. The population of PWID estimated in five selected districts using the two capture-recapture method (CRC) (median = 5,396, 95% CI: 4,011-9,100) was slightly lower than estimated using SS-PSE with RDS survey 1 (median = 5,580, 95% CI: 3,024-9,272) and higher than when using SS-PSE with RDS survey 2 (median = 4,793; 95% CI: 2,310-8,618). The provincial PWID population estimates based on various approaches (e.g. extrapolation based on the prevalence of PWID in the districts) ranged from 6,498 (95% CI: 4,829-10,957) to around 6,807 (95% CI: 5,341-10,527). A provincial estimate of 6,782 PWID, with a confidence interval ranging from 5,312 to 10,527, will help guide planning and resource allocation to support appropriate levels of HIV prevention, care, and treatment services in the Thai Nguyen province.

As authorities braced for the arrival of the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), infrastructure investments and government directives prompted action in central Viet Nam to establish capacity for genomic surveillance sequencing. From 17 November 2021 to 7 January 2022, the Pasteur Institute in Nha Trang sequenced 162 specimens from 98 150 confirmed SARS-CoV-2 cases in the region collected from 8 November to 31 December 2021. Of these, all 127 domestic cases were identified as the B.1.617.2 (Delta) variant, whereas 92% (32/35) of imported cases were identified as the B.1.1.529 (Omicron) variant, all among international flight passengers. Patients were successfully isolated, enabling health-care workers to prepare for additional cases. Most (78%) of the 32 Omicron cases were fully vaccinated, suggesting continued importance of public health and social measures to control the spread of new variants.

Background: Molecular diagnostics are considered the most promising route to achievement of rapid, universal drug susceptibility testing for Mycobacterium tuberculosis complex (MTBC). We aimed to generate a WHO-endorsed catalogue of mutations to serve as a global standard for interpreting molecular information for drug resistance prediction. Methods: In this systematic analysis, we used a candidate gene approach to identify mutations associated with resistance or consistent with susceptibility for 13 WHO-endorsed antituberculosis drugs. We collected existing worldwide MTBC whole-genome sequencing data and phenotypic data from academic groups and consortia, reference laboratories, public health organisations, and published literature. We categorised phenotypes as follows: methods and critical concentrations currently endorsed by WHO (category 1); critical concentrations previously endorsed by WHO for those methods (category 2); methods or critical concentrations not currently endorsed by WHO (category 3). For each mutation, we used a contingency table of binary phenotypes and presence or absence of the mutation to compute positive predictive value, and we used Fisher's exact tests to generate odds ratios and Benjamini-Hochberg corrected p values. Mutations were graded as associated with resistance if present in at least five isolates, if the odds ratio was more than 1 with a statistically significant corrected p value, and if the lower bound of the 95% CI on the positive predictive value for phenotypic resistance was greater than 25%. A series of expert rules were applied for final confidence grading of each mutation. Findings: We analysed 41 137 MTBC isolates with phenotypic and whole-genome sequencing data from 45 countries. 38 215 MTBC isolates passed quality control steps and were included in the final analysis. 15 667 associations were computed for 13 211 unique mutations linked to one or more drugs. 1149 (73%) of 15 667 mutations were classified as associated with phenotypic resistance and 107 (07%) were deemed consistent with susceptibility. For rifampicin, isoniazid, ethambutol, fluoroquinolones, and streptomycin, the mutations' pooled sensitivity was more than 80%. Specificity was over 95% for all drugs except ethionamide (914%), moxifloxacin (916%) and ethambutol (933%). Only two resistance mutations were identified for bedaquiline, delamanid, clofazimine, and linezolid as prevalence of phenotypic resistance was low for these drugs. Interpretation: We present the first WHO-endorsed catalogue of molecular targets for MTBC drug susceptibility testing, which is intended to provide a global standard for resistance interpretation. The existence of this catalogue should encourage the implementation of molecular diagnostics by national tuberculosis programmes. Funding: Unitaid, Wellcome Trust, UK Medical Research Council, and Bill and Melinda Gates Foundation. 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license

Whole genome sequencing (WGS) of Salmonella supports both molecular typing and detection of antimicrobial resistance (AMR). Here, we evaluated the correlation between phenotypic antimicrobial susceptibility testing (AST) and in silico prediction of AMR from WGS in Salmonella enterica (n = 1321) isolated from human infections in Canada. Phenotypic AMR results from broth microdilution testing were used as the gold standard. To facilitate high-throughput prediction of AMR from genome assemblies, we created a tool called Staramr, which incorporates the ResFinder and PointFinder databases and a custom gene-drug key for antibiogram prediction. Overall, there was 99% concordance between phenotypic and genotypic detection of categorical resistance for 14 antimicrobials in 1321 isolates (18,305 of 18,494 results in agreement). We observed an average sensitivity of 91.2% (range 80.5100%), a specificity of 99.7% (98.6100%), a positive predictive value of 95.4% (68.2100%), and a negative predictive value of 99.1% (95.6100%). The positive predictive value of gentamicin was 68%, due to seven isolates that carried aac(3)-IVa, which conferred MICs just below the breakpoint of resistance. Genetic mechanisms of resistance in these 1321 isolates included 64 unique acquired alleles and mutations in three chromosomal genes. In general, in silico prediction of AMR in Salmonella was reliable compared to the gold standard of broth microdilution. WGS can provide higher-resolution data on the epidemiology of resistance mechanisms and the emergence of new resistance alleles. 2022 by the authors. Licensee MDPI, Basel, Switzerland.

INTRODUCTION: A study was conducted in three districts in Hai Phong province, Vietnam to estimate the population size of the Female Sex Workers (FSW) in June-July 2019. METHODS: The procedures included selection of three districts, compilation of a list of accessible venues where FSW congregate, distribution of first unique objects (first capture) and second unique objects (second capture) to FSW in randomly selected venues and implementation of a Mini-Respondent Driven Sampling (mRDS) Survey (third capture). Population size of the FSW was calculated based on the number of FSW in each round, number of FSW 'recaptured' during the second and the third captures. Additionally, personal network size data captured in the mRDS was used to measure the population of FSW within the three districts using Successive Sampling Population Size Estimates (SS-PSE). RESULTS: The total estimated FSWs in the three selected districts, using Three Source Capture-Recapture (3S-CRC) was 958, which is slightly lower than that estimated using SS-PSE - 1192. The 3S-CRC method yielded a provincial estimate of 1911 while the SS-PSE method resulted in a total of 2379 FSW for the province. CONCLUSION: Two techniques produced different PSE at both the district and the province levels and resulted in estimates lower than ones produced using programmatic data. For planning HIV prevention and care service needs among all FSWs, additional studies are needed to estimate the number of sex workers who are not venue-based and use social media platforms to sell services.

Vietnam has been conducting HIV/sexually transmitted infection (STI) integrated bio-behavioral surveillance surveys on men who have sex with men (MSM) as well as other key populations since 2005. Although HIV prevalence in the Vietnamese general population remains below 1%, it is expected to be much higher among MSM.Data on HIV prevalence and sexual and drug use behaviors were collected from MSM in Ho Chi Minh City (HCMC) in 2006 (n = 397), 2009 (n = 399) and 2013 (n = 350) using respondent-driven sampling. Eligible participants were males, aged ≥15 years who reported having manual, oral, or anal sexual activity with males in the past year and lived, worked or socialized in HCMC.HIV seroprevalence among MSM was 5.8% in 2006, 16.1% in 2009 and 12.1% in 2013 and prevalence of at least one STI (syphilis, gonorrhea and/or chlamydia infection) was 11.4% in 2006 and 15.6% in 2009 (no data for 2013). Significant, but small, increasing trends were found for MSM who reported ever testing and receiving results for HIV and for HIV prevalence. No significant changes for condom use, injecting and non-injecting drug use, or and receipt of free condoms were observed.Although a small percentage of MSM reported injecting drugs, HIV was positively associated with ever injecting drugs. Programs targeting MSM should include screening and treatment for injection drug use to most effectively control the HIV/AIDS epidemic among MSM in HCMC.

We describe the epidemiological characteristics, pattern of circulation, and geographical distribution of influenza B viruses and its lineages using data from the Global Influenza B Study. We included over 1.8 million influenza cases occurred in thirty-one countries during 2000-2018. We calculated the proportion of cases caused by influenza B and its lineages; determined the timing of influenza A and B epidemics; compared the age distribution of B/Victoria and B/Yamagata cases; and evaluated the frequency of lineage-level mismatch for the trivalent vaccine. The median proportion of influenza cases caused by influenza B virus was 23.4%, with a tendency (borderline statistical significance, p = 0.060) to be higher in tropical vs. temperate countries. Influenza B was the dominant virus type in about one every seven seasons. In temperate countries, influenza B epidemics occurred on average three weeks later than influenza A epidemics; no consistent pattern emerged in the tropics. The two B lineages caused a comparable proportion of influenza B cases globally, however the B/Yamagata was more frequent in temperate countries, and the B/Victoria in the tropics (p = 0.048). B/Yamagata patients were significantly older than B/Victoria patients in almost all countries. A lineage-level vaccine mismatch was observed in over 40% of seasons in temperate countries and in 30% of seasons in the tropics. The type B virus caused a substantial proportion of influenza infections globally in the 21st century, and its two virus lineages differed in terms of age and geographical distribution of patients. These findings will help inform health policy decisions aiming to reduce disease burden associated with seasonal influenza.

OBJECTIVES: Early diagnosis of tuberculosis (TB) and multidrug-resistant TB (MDR-TB) is a priority for Viet Nam's National TB Control Programme. In many laboratories, quality systems are weak; few have attained accreditation. We implemented a structured training and mentoring program for TB laboratories and measured impact on quality. METHODS: Six TB culture laboratories implemented the Strengthening TB Laboratory Management Towards Accreditation (TB SLMTA) program, consisting of three training workshops and on-site mentoring between workshops to support improvement projects. Periodic audits, using standardized checklists, monitored laboratories' progress toward accreditation readiness. RESULTS: At baseline, all six laboratories achieved a zero-star level. At exit, five laboratories attained three stars and another one star. Overall checklist scores increased by 44.2% on average, from 29.8% to 74.0%; improvements occurred across all quality system essentials. CONCLUSIONS: The program led to improved quality systems. Sites should be monitored to ensure sustainability of improvements and country capacity expanded for national scaleup.

Injection drug use and heterosexual transmission from male key populations to their female partners have been the dominant modes of HIV transmission in Vietnam. A demonstration project was conducted to offer immediate antiretroviral therapy (ART) (regardless of CD4 cell count) to HIV-seropositive partners in serodiscordant couples. During March-December 2013, couples HIV testing and counselling (HTC) and immediate ART were offered in two drug use-affected provinces. Of 256 couples receiving couples HTC, 146 (57%) were serodiscordant; 134 (92%) seropositive partners initiated ART irrespective of CD4 cell count. Of these, 86% were male; 57% reported ever using illicit drugs; median CD4 cell count before ART initiation was 374 cells/mm(3). Consistent condom use was reported by 58, 70 and 71% among HIV-positive partners at months 0, 3 and 12. At 12 months after ART initiation, 119 (89%) HIV-positive partners were retained in care; 96 (95% of those tested) achieved viral suppression (<1000 copies/ml). Uptake of immediate ART and viral suppression among those initiating ART were high, paving the way for ART regardless of CD4 cell count as national policy in Vietnam.

Jamestown Canyon virus (JCV), a mosquito-borne Orthobunyavirus (within the California serogroup), can cause severe neuroinvasive disease. According to national data during 2000-2013, 42% of the 31 documented JCV disease cases in the United States were detected in residents from Wisconsin. The Wisconsin Division of Public Health enhanced JCV surveillance by implementing routine use of JCV-specific immunoglobulin M (IgM) antibody testing followed by confirmatory JCV-specific plaque reduction neutralization testing on all patients with suspected cases of arboviral infection who had tests positive for arboviral immunoglobin at commercial laboratories. During 2011-2016, of the 287 Wisconsin specimens tested on the Arbovirus IgM Antibody Panel, 30 JCV cases were identified (26 confirmed and four probable). Twenty-seven (90%) JCV cases were detected after 2013. Among all cases, 17 (56%) were male and the median age was 54 years (range: 10-84 years). Fifteen patients had neuroinvasive disease, including meningitis (n = 9) and meningoencephalitis (n = 6). Although historically considered rare, the relatively high rate (0.12 cases/100,000 population) of diagnosis of JCV infections among Wisconsin residents during 2013-2016 compared with that in previous years suggests occurrence is widespread throughout Wisconsin and historically may have been under-recognized. This study aims to raise awareness of JCV infection for differential diagnosis among the arboviral diseases. Improved and timely diagnosis of arboviral disease is important in that it will provide more information regarding emerging infections and promote preventive measures to avoid mosquito-borne exposure and infection among residents of and visitors to affected areas.

Foodborne salmonellosis causes an estimated 1 million illnesses and 400 deaths annually in the United States (1). In recent years, salmonellosis outbreaks have been caused by foods not typically associated with Salmonella. On May 2, 2017, PulseNet, CDC's national molecular subtyping network for foodborne disease surveillance, identified a cluster of 14 Salmonella Chailey isolates with a rare pulsed-field gel electrophoresis (PFGE) pattern. On May 29, Canadian health officials informed CDC that they were also investigating a cluster of five Salmonella Chailey infections in British Columbia with the same PFGE pattern. Nineteen cases were identified and investigated by CDC, U.S. state health departments, the Public Health Agency of Canada, and the British Columbia Centre for Disease Control. Isolates from all cases were highly related by whole genome sequencing (WGS). Illness onset dates ranged from March 10 to May 7, 2017. Initial interviews revealed that infected persons consumed various fresh foods and shopped at grocery chain A; focused questionnaires identified precut coconut pieces from grocery chain A as a common vehicle. The Canadian Food Inspection Agency (CFIA) and the U.S. Food and Drug Administration (FDA) conducted a traceback investigation that implicated a single lot of frozen, precut coconut as the outbreak source. Grocery chain A voluntarily removed precut coconut pieces from their stores. This action likely limited the size and scope of this outbreak.

OBJECTIVE To identify knowledge and practices related to rabies vaccination and serologic monitoring among animal care workers in the United States. DESIGN Cross-sectional survey. SAMPLE 2,334 animal care workers (ie, veterinarians, veterinary technicians, animal control workers, and wildlife rehabilitators). PROCEDURES Participants were contacted through relevant professional organizations to participate in an anonymous web-based survey. The survey collected demographic and occupational information, animal handling and potential rabies exposure information, and individual rabies vaccination and serologic monitoring practices. Comparisons of animal bite and rabies exposure rates were made between occupational groups. Multiple logistic regression was used to evaluate factors associated with rabies vaccination status and adherence to serologic monitoring recommendations. RESULTS Respondents reported 0.77 animal bites/person-year or 0.10 bites/1,000 animals handled. The overall rate of postexposure prophylaxis due to an occupational rabies exposure was 1.07/100 person-years. Veterinarians reported the highest rabies vaccination rate (98.7% [367/372]), followed by animal control workers (78.5% [344/438]), wildlife rehabilitators (78.2% [122/156]), and veterinary technicians (69.3% [937/1,352]). Respondents working for employers requiring rabies vaccination and serologic monitoring were 32.16 and 6.14 times, respectively, as likely to be vaccinated or have a current serologic monitoring status as were respondents working for employers without such policies. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that, given the high reported rates of animal bites and potential rabies exposures among animal care workers, improvements in rabies vaccination and serologic monitoring practices are needed.

BACKGROUND: Influenza disease burden varies by age and this has important public health implications. We compared the proportional distribution of different influenza virus types within age strata using surveillance data from twenty-nine countries during 1999-2014 (N=358,796 influenza cases). METHODS: For each virus, we calculated a Relative Illness Ratio (defined as the ratio of the percentage of cases in an age group to the percentage of the country population in the same age group) for young children (0-4 years), older children (5-17 years), young adults (18-39 years), older adults (40-64 years), and the elderly (65+ years). We used random-effects meta-analysis models to obtain summary relative illness ratios (sRIRs), and conducted meta-regression and sub-group analyses to explore causes of between-estimates heterogeneity. RESULTS: The influenza virus with highest sRIR was A(H1N1) for young children, B for older children, A(H1N1)pdm2009 for adults, and (A(H3N2) for the elderly. As expected, considering the diverse nature of the national surveillance datasets included in our analysis, between-estimates heterogeneity was high (I(2)>90%) for most sRIRs. The variations of countries' geographic, demographic and economic characteristics and the proportion of outpatients among reported influenza cases explained only part of the heterogeneity, suggesting that multiple factors were at play. CONCLUSIONS: These results highlight the importance of presenting burden of disease estimates by age group and virus (sub)type.

Highly pathogenic avian influenza (HPAI) A(H5N1) viruses pose a significant economic burden to the poultry industry worldwide and have pandemic potential. Poultry vaccination against HPAI A(H5N1) viruses has been an important component of HPAI control measures and has been performed in Vietnam since 2005. To systematically assess antigenic matching of current vaccines to circulating field variants, we produced a panel of chicken and ferret antisera raised against historical and contemporary Vietnamese reference viruses representing clade variants that were detected between 2001 and 2014. The antisera were used for hemagglutination inhibition (HI) assays to generate data sets for analysis by antigenic cartography, allowing for a direct comparison of results from chicken or ferret antisera. HI antigenic maps, developed with antisera from both hosts, revealed varying patterns of antigenic relationships and clustering of viruses that were dependent on the clade of viruses analyzed. Antigenic relationships between existing poultry vaccines and circulating field viruses were also aligned with in vivo protection profiles determined by previously reported vaccine challenge studies. Our results establish the feasibility and utility of HPAI A(H5N1) antigenic characterization using chicken antisera and support further experimental and modeling studies to investigate quantitative relationships between genetic variation, antigenic drift and correlates of poultry vaccine protection in vivo.

BACKGROUND: In 2016, as a component of the Global Health Security Agenda, the Vietnam Ministry of Health expanded its existing influenza sentinel surveillance for severe acute respiratory infections (SARI) to include testing for 7 additional viral respiratory pathogens. This article describes the steps taken to implement expanded SARI surveillance in Vietnam and reports data from 1 year of expanded surveillance. METHOD: The process of expanding the suite of pathogens for routine testing by real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) included laboratory trainings, procurement/distribution of reagents, and strengthening and aligning SARI surveillance epidemiology practices at sentinel sites and regional institutes (RI). RESULTS: Surveillance data showed that of 4,003 specimens tested by the RI laboratories, 20.2% (n = 810) were positive for influenza virus. Of the 3,193 influenza-negative specimens, 41.8% (n = 1,337) were positive for at least 1 non-influenza respiratory virus, of which 16.2% (n = 518), 13.4% (n = 428), and 9.6% (n = 308) tested positive for respiratory syncytial virus, rhinovirus, and adenovirus, respectively. CONCLUSIONS: The Government of Vietnam has demonstrated that expanding respiratory viral surveillance by strengthening and building upon an influenza platform is feasible, efficient, and practical. This article is protected by copyright. All rights reserved.

BACKGROUND: Methadone maintenance treatment (MMT) is highly effective for reducing heroin use and HIV transmission among people who inject opioids. We sought to measure and understand factors associated with continued heroin use, a critical factor affecting treatment outcome among MMT patients in Vietnam. METHOD: We collected data from medical charts of a nationally representative sample of patients who were on MMT from May 2008 to December 2013. We selected 10 MMT clinics using probability proportional to size and 50 patients/clinic by systematic random sampling. Concurrent heroin use was defined by self-report/positive urine test recorded in patient charts during month 3, 6, 12, and 24 after MMT initiation. We used multivariable logistic regression to identify factors associated with concurrent heroin use over the first 24 months in treatment. FINDINGS: All clients used heroin at baseline; concurrent heroin use was 55% at month 3; 19%, 14.6% and 15.2% at month 6, 12, and 24, respectively. Having no family emotional/financial support at baseline versus having this support (AOR=2.03; 95% confidence interval [CI]=1.17-3.53); using heroin for <15years versus >/=15 years at baseline (AOR=1.55; 95% CI=1.01-2.38); being HIV-infected/not on antiretroviral treatment (ART; AOR=1.79; 95% CI=1.07-2.98) or being HIV infected/on ART (AOR=2.39; 95% CI=1.61-3.55), versus not being HIV infected; baseline methamphetamine use versus non-use (AOR=2.68; 95% CI=1.08-6.65), were associated with increased odds of concurrent heroin use among patients. CONCLUSION: The association between concurrent heroin use among MMT patients and lack of family emotional/financial support, highlights the critical importance of these types of support for successful treatment. Association with shorter heroin use history suggests motivational enhancement may reduce concurrent heroin use. Living with HIV, whether on ART or not, is associated with increased concurrent heroin use and suggests safe injection commodities and education, and drug-drug interaction management, are needed for this subgroup. Though few MMT clients reported baseline methamphetamine use, its association with later heroin use suggests the need for effective methamphetamine use interventions.

Mutation and reassortment of highly pathogenic avian influenza A(H5N1) viruses at the animal-human interface remain a major concern for emergence of viruses with pandemic potential. To understand the relationship of H5N1 viruses circulating in poultry and those isolated from humans, comprehensive phylogenetic and molecular analyses of viruses collected from both hosts in Vietnam between 2003 and 2010 were performed. We examined the temporal and spatial distribution of human cases relative to H5N1 poultry outbreaks and characterized the genetic lineages and amino acid substitutions in each gene segment identified in humans relative to closely related viruses from avian hosts. Six hemagglutinin clades and 8 genotypes were identified in humans, all of which were initially identified in poultry. Several amino acid mutations throughout the genomes of viruses isolated from humans were identified, indicating the potential for poultry viruses infecting humans to rapidly acquire molecular markers associated with mammalian adaptation and antiviral resistance.

We have previously described a novel taxon of the genus Ehrlichia (type strain WisconsinT), closely related to Ehrlichia muris, that causes human ehrlichiosis among patients with exposures to ticks in the upper midwestern USA. DNA from this bacterium was also detected in Ixodes scapularis and Peromyscus leucopus collected in Minnesota and Wisconsin. To determine the relationship between the E. muris-like agent (EMLA) and other species of the genus Ehrlichia phenotypic, genotypic and epidemiologic comparisons were undertaken, including sequence analysis of eight gene loci (3906 nucleotides) for 39 EMLA DNA samples and the type strain of E. muris AS145T. Three loci were also sequenced from DNA of nine strains of E. muris from mouse spleens from Japan. All sequences from E. muris were distinct from homologous EMLA sequences, but differences between them were less than those observed among other species of the genus Ehrlichia. Phenotypic comparison of EMLA and E. muris revealed similar culture and electron microscopic characteristics, but important differences were noted in their geographic distribution, ecological associations and behavior in mouse models of infection. Based on these comparisons, we propose that type strain WisconsinT represents a novel subspecies, Ehrlichia murissubsp. eauclairensis,subsp. nov. This strain is available through the Centers for Disease Control and Prevention Rickettsial Isolate Reference Collection (CRIRC EMU002T) and through the Collection de Souches de l'Unite des Rickettsies (CSURP2883 T). The subspecies Ehrlichia murissubsp. muris subsp. nov. is automatically created and the type strain AS145T is also available through the same collections (CRIRC EMU001T, CSUR E2T). Included is an emended description of E. muris.