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Hepatitis E virus (HEV), the etiologic agent of hepatitis E, is a nonenveloped, positive-sense single-stranded RNA virus, [approximately equal to] 7.2 kb in length, of the family Hepeviridae. HEV, identified [...]

Background Sapovirus is one of the principal agents of acute viral enteritis in children. Because it has not been routinely included in diagnostic evaluations, the epidemiology and natural history remain poorly described. Methods A birth cohort of 1715 children from 8 countries contributed surveillance samples (n = 35 620) and diarrheal specimens (n = 6868) from 0 to 24 months of age. Sapovirus was detected by quantitative polymerase chain reaction concurrently to other enteropathogens using multiarray cards. Logistic regression was used to identify risk factors, and longitudinal models were employed to estimate incidence rates and evaluate evidence of protective immunity. Results Sapovirus was detected in 24.7% (n = 1665) of diarrheal stools and 12.8% (n = 4429) of monthly surveillance samples. More than 90% of children were infected and 60% experienced sapovirus diarrhea in the first 2 years of life. Breastfeeding and higher socioeconomic status were associated with reduced incidence of infection and illness. Specimens with sapovirus detected had an increased odds of coinfection with rotavirus (odds ratio [OR], 1.6 [95% confidence interval {CI}, 1.3–2.0]), astrovirus (OR, 1.5 [95% CI, 1.3–1.7]), adenovirus (OR, 1.3 [95% CI, 1.1–1.5]), and Shigella (OR, 1.4 [95% CI, 1.3–1.6]). Prior infection with sapovirus conferred a risk reduction of 22% for subsequent infection (hazard ratio [HR], 0.78 [95% CI,.74–.85]) and 24% for subsequent diarrhea (95% CI, 11.0%–35.0%; HR, 0.76). Conclusions Sapovirus is a common cause of early childhood diarrhea. Further research on coinfections is warranted. Evidence of acquired immunity was observed even in the absence of genotype-specific analysis for this pathogen of known genetic diversity. [ABSTRACT FROM AUTHOR]

Background Antimicrobial resistance is a major issue in the Shigellae, particularly as a specific multidrug-resistant (MDR) lineage of Shigella sonnei (lineage III) is becoming globally dominant. Ciprofloxacin is a recommended treatment for Shigella infections. However, ciprofloxacin-resistant S. sonnei are being increasingly isolated in Asia and sporadically reported on other continents. We hypothesized that Asia is a primary hub for the recent international spread of ciprofloxacin-resistant S. sonnei. Methods and Findings We performed whole-genome sequencing on a collection of 60 contemporaneous ciprofloxacin-resistant S. sonnei isolated in four countries within Asia (Vietnam, n = 11; Bhutan, n = 12; Thailand, n = 1; Cambodia, n = 1) and two outside of Asia (Australia, n = 19; Ireland, n = 16). We reconstructed the recent evolutionary history of these organisms and combined these data with their geographical location of isolation. Placing these sequences into a global phylogeny, we found that all ciprofloxacin-resistant S. sonnei formed a single clade within a Central Asian expansion of lineage III. Furthermore, our data show that resistance to ciprofloxacin within S. sonnei may be globally attributed to a single clonal emergence event, encompassing sequential gyrA-S83L, parC-S80I, and gyrA-D87G mutations. Geographical data predict that South Asia is the likely primary source of these organisms, which are being regularly exported across Asia and intercontinentally into Australia, the United States and Europe. Our analysis was limited by the number of S. sonnei sequences available from diverse geographical areas and time periods, and we cannot discount the potential existence of other unsampled reservoir populations of antimicrobial-resistant S. sonnei. Conclusions This study suggests that a single clone, which is widespread in South Asia, is likely driving the current intercontinental surge of ciprofloxacin-resistant S. sonnei and is capable of establishing endemic transmission in new locations. Despite being limited in geographical scope, our work has major implications for understanding the international transfer of antimicrobial-resistant pathogens, with S. sonnei acting as a tractable model for studying how antimicrobial-resistant Gram-negative bacteria spread globally., Author(s): Hao Chung The 1, Maia A. Rabaa 1,2, Duy Pham Thanh 1, Niall De Lappe 3, Martin Cormican 4, Mary Valcanis 5, Benjamin P. Howden 5, Sonam Wangchuk 6, [...]

To the Editor: Intravenous immunoglobulin (IVIg) is used to treat bacterial and viral infections in patients with primary immunodeficiency disease and those with autoimmune and inflammatory disorders (1). IVIg contains [...]

Recently there has been resurgence in the number of cases of measles, mumps, and rubella (German measles). Many of these cases are occurring not in the young child, as in the past, but in teenagers and young adults. A study was undertaken to determine the level of immunity of young adults, in an effort to provide information to those who make national and military immunization policy decisions. There were 1,547 US army recruits included in the study; the recruits were given a questionnaire and blood samples were obtained. Blood samples were evaluated for antibody status (presence of antibodies indicates immunity) against measles, mumps, rubella, and varicella (chicken pox), as well as poliovirus types 1, 2, and 3. The results of the blood analysis revealed that 20.7 percent of recruits were without antibodies against measles; 15.6 percent, against mumps; 17.6 percent against rubella; and 6.9 percent against varicella. Susceptibility to measles, mumps, and rubella was less in women, blacks, and college-educated recruits; women and backs were more susceptible to varicella. Older recruits (those born before 1970) more often had immunity to measles, mumps and rubella than did younger recruits. A total of 2.3 percent of the recruits lacked immunity to polio type 1; 0.6 percent to type 2; and 14.6 percent to type 3. It is concluded that immunity to measles, mumps, and rubella is unevenly distributed among young Americans. These findings support the national objective of improving immunization in school children and young adults. Results support legislation which would require those entering college to present evidence of at least two measles vaccinations, one of which having been given at or after admission to elementary school. (Consumer Summary produced by Reliance Medical Information, Inc.)

Abstract Background Campylobacter jejuni, a gram-negative bacterium, is a frequent cause of gastrointestinal food-borne illness in humans throughout the world. There are several reports that the virulence of C. jejuni might be modulated by non-flagellar proteins that are secreted through the filament. Recently, FspA (Flagella secreted proteins) have been described. Two alleles of fspA (fspA1 and fspA2) based on sequence analysis were previously reported and only the fspA2 allele was found in Thai isolates. The aim of this study is to analyze the deduced amino acid sequences fspA and the adjacent putative integral membrane protein from 103 Thai C. jejuni isolates. Results A total of 103 representative C. jejuni isolates were amplified by PCR for the fspA gene and the adjacent integral membrane protein gene. Two PCR product sizes were amplified using the same primers, an approximately 1600-bp PCR product from 19 strains that contained fspA and integral membrane protein genes and an approximately 800-bp PCR product from 84 strains that contained only the fspA gene. DNA sequencing was performed on the amplified products. The deduced amino acid sequences of both genes were analyzed separately using CLC Free Workbench 4 software. The analysis revealed three groups of FspA. Only FspA group 1 sequences (19/103) (corresponding to fspA1) consisting of 5 subgroups were associated with the adjacent gene encoding the integral membrane protein. FspA group 2 was the largest group (67/103) consisting of 9 subgroups. FspA group 2p (17/103) consisting of 7 subgroups was found to contain stop codons at a position before the terminal 142 position. Conclusions This study reveals greater heterogeneity of FspA (group 1, 2 and 2p) among Thai C. jejuni isolates than previously reported. Furthermore, the subgroups of FspA groups 1 were associated with groups of integral membrane protein. The significance of these different FspA variants to virulence requires further study.

Abstract Background Shigella is a frequent cause of bacterial dysentery in the developing world. Treatment with effective antibiotics is recommended for shigellosis, but options become limited due to globally emerging resistance. One of the mechanisms for the development of resistance utilizes integrons. This study described the antibiotic susceptibility and the presence of class 1 and 2 integrons in S. flexneri and S. sonnei isolated in Uzbekistan. Results We studied 31 isolates of S. flexneri and 21 isolates of S. sonnei isolated in Uzbekistan between 1992 and 2007 for the susceptibility or resistance to ampicillin (Am), chloramphenicol (Cl), tetracycline (Te), co-trimoxazole (Sxt), kanamycin (Km), streptomycin (Str), gentamicin (Gm), cefazolin (Czn), cefoperazone (Cpr), cefuroxime (Cur), ceftazidime (Ctz), nalidixic acid (NA) and ciprofloxacin (Cip). Am/Str/Cl/Te and Am/Str/Cl/Te/Sxt resistance patterns were found most frequently in S. flexneri. Single isolates were resistant to aminoglycoside, quinolones and cephalosporins. The resistance patterns were different in the two species. Integrons were detected in 93.5% of S. flexneri (29/31) and 81.0% of S. sonnei (17/21) isolates. In addition, 61.3% of S. flexneri (19/31) isolates and 19.0% of S. sonnei (4/21) isolates carried both classes of integrons. In 29.0% of S. flexneri (9/31) isolates, only class 1 integrons were identified. In S. flexneri isolates, the presence of class 1 integrons was associated with resistance to ampicillin and chloramphenicol. Only Class 2 integrons were present in 61.9% of S. sonnei (13/21) isolates. Conclusions Our study documents antibiotic resistance among Shigella spp. in Uzbekistan. Ninety percent of Shigella strains were resistant to previously used antibiotics. Differences among S. flexneri and S. sonnei isolates in patterns of antimicrobial resistance to routinely used shigellosis antibiotics were observed. The majority of S. flexneri were resistant to ampicillin, chloramphenicol, tetracycline and streptomycin. Class 1 and 2 integrons were widely present in these Shigella strains. Resistance to ampicillin/chloramphenicol was associated with the presence of class 1 integrons. Though several mechanisms are possible, the resistance of Shigella isolates to ampicillin/chloramphenicol may be associated with the expression of genes within class 1 integrons.