An Updated Assessment of Chronic Hepatitis B Prevalence Among Foreign-Born Persons Living in the United States.

BACKGROUND AND AIMS: Although prevalence of chronic hepatitis B (CHB) in the USA includes 0.42 million (range, 0.28-0.67) U.S.-born persons, foreign-born (FB) persons contribute a substantially larger number to the burden of CHB in the USA. Over the past decade, patterns of U.S. immigration have changed and many countries have implemented HBV prevention programs. This study aims to estimate the number of FB persons with CHB in the USA by country of origin, updating our 2011 study. APPROACH AND RESULTS: We performed systematic searches for articles published in 2009-2019 reporting HBsAg seroprevalence in emigrants and in-country populations of 117 countries. Data meeting inclusion criteria were combined with data from our 2011 study to calculate pooled prevalence estimates for 99 countries using meta-analyses (total 2,800 surveys involving 112 million subjects). Combining country-specific CHB rate estimates with the number of FB in the USA in 2018, by country of origin from the U.S. Census Bureau, we estimate that the number of FB with CHB in the USA in 2018 was 1.47 million (95% CI, 1.21-1.73), substantially higher than previously reported. The weighted average CHB prevalence for all FB in the USA in 2018 was 3.07%. Approximately 59% of FB with CHB in the USA in 2018 emigrated from Asia, 19% from the Americas, and 15% from Africa. Subgroup analyses found that for many countries, CHB rates are higher in males than females and have declined over the past three decades, but no consistent pattern is observed between emigrant and in-country rates. CONCLUSIONS: Including FB and U.S.-born persons, the total prevalence of CHB in the USA may be as high as 2.4 million.

Prevalence of chronic hepatitis B among foreign-born persons living in the United States by country of origin.

Estimates of the prevalence of chronic hepatitis B (CHB) in the United States differ significantly, and the contribution of foreign-born (FB) persons has not been adequately described. The aim of this study was to estimate the number of FB persons in the United States living with CHB by their country of origin. We performed a systematic review for reports of HBsAg seroprevalence rates in 102 countries (covering PubMed from 1980 to July 2010). Data from 1,373 articles meeting inclusion criteria were extracted into country-specific databases. We identified 256 seroprevalence surveys in emigrants from 52 countries (including 689,078 persons) and 1,797 surveys in the general populations of 98 countries (including 17,861,035 persons). Surveys including individuals with lower or higher risk of CHB than the general population were excluded. Data were combined using meta-analytic methods to determine country-specific pooled CHB prevalence rates. Rates were multiplied by the number of FB living in the United States in 2009 by country of birth from the U.S. Census Bureau to yield the number of FB with CHB from each country. We estimate a total of 1.32 million (95% confidence interval: 1.04-1.61) FB in the United States living with CHB in 2009; 58% migrated from Asia and 11% migrated from Africa, where hepatitis B is highly endemic. Approximately 7% migrated from Central America, a region with lower CHB rates, but many more emigrants to the United States. This analysis suggests that the number of FB persons living with CHB in the United States may be significantly greater than previously reported. Assuming 300,000-600,000 U.S.-born persons with CHB, the total prevalence of CHB in the United States may be as high as 2.2 million.

Performance of an automatic external cardioverter-defibrillator algorithm in the discrimination of supraventricular from ventricular tachycardia.

An automatic external cardioverter-defibrillator (AECD) with a programmable supraventricular-ventricular tachycardia (VT) zone underwent evaluation of arrhythmia discrimination performance in the electrophysiologic laboratory during induced supraventricular tachycardia (SVT) and unipolar and bipolar atrial pacing. The AECD SVT zone was programmed so that the induced SVT rate would fall within this zone. Atrial pacing was also performed at a rate within this zone. The ability of the AECD to accurately discriminate between VT and SVT and to recommend shock delivery was assessed. A total of 98 patients underwent conventional diagnostic electrophysiologic studies (49 men, age 59 +/- 19 years) with a total of 55 inducible sustained SVTs. High right atrial pacing was performed in 56 patients in unipolar and in 82 patients in bipolar fashion. In response to induced sustained SVT, the AECD correctly classified 47 episodes as nonshockable, 4 incorrectly as shockable, and 4 episodes correctly as shockable with a resultant sensitivity of 100% and specificity of 92%. Bipolar high right atrial pacing was correctly identified as nonshockable in 75 episodes, incorrectly identified as shockable in 5 episodes, and correctly identified as shockable in 2 episodes with a resultant sensitivity of 100% and specificity of 94%. The Powerheart AECD accurately discriminates SVT from VT and is expected to correctly deliver automatic external shocks rapidly in the presence of spontaneous life-threatening tachycardia and appropriately withhold therapy during SVT.

Seasonal fluctuations in ionic concentrations drive microbial succession in a hypersaline lake community.

Microbial community succession was examined over a two-year period using spatially and temporally coordinated water chemistry measurements, metagenomic sequencing, phylogenetic binning and de novo metagenomic assembly in the extreme hypersaline habitat of Lake Tyrrell, Victoria, Australia. Relative abundances of Haloquadratum-related sequences were positively correlated with co-varying concentrations of potassium, magnesium and sulfate, but not sodium, chloride or calcium ions, while relative abundances of Halorubrum, Haloarcula, Halonotius, Halobaculum and Salinibacter-related sequences correlated negatively with Haloquadratum and these same ionic factors. Nanohaloarchaea and Halorhabdus-related sequence abundances were inversely correlated with each other, but not other taxonomic groups. These data, along with predicted gene functions from nearly-complete assembled population metagenomes, suggest different ecological phenotypes for Nanohaloarchaea and Halorhabdus-related strains versus other community members. Nucleotide percent G+C compositions were consistently lower in community metagenomic reads from summer versus winter samples. The same seasonal G+C trends were observed within taxonomically binned read subsets from each of seven different genus-level archaeal groups. Relative seasonal abundances were also linked to percent G+C for assembled population genomes. Together, these data suggest that extreme ionic conditions may exert selective pressure on archaeal populations at the level of genomic nucleotide composition, thus contributing to seasonal successional processes. Despite the unavailability of cultured representatives for most of the organisms identified in this study, effective coordination of physical and biological measurements has enabled discovery and quantification of unexpected taxon-specific, environmentally mediated factors influencing microbial community structure.