On a Multinational Assessment of Rotavirus Disease in Europe

Rotaviruses were discovered in the 1960s in animals and in the 1970s in humans; the latter discovery was made by an intrepid group who performed duodenal biopsies on children with acute gastroenteritis (AGE) [1]. By the late 1970s, data already clearly indicated that rotavirus was the cause of the annual winter peak of AGE affecting young children, as well as a frequent cause of severe gastroenteritis in various animal species (e.g., [2–5]). Use of the retrospectroscope clarified or left as tantalizing the suggestion that rotaviruses were the cause of the annual “winter vomiting syndrome” first described in children in 1910 in Japan [6] and in 1929 in the United States [7]. The recognition of that winter peak was a result of improved water and sewage handling that markedly reduced exposure to bacterial and parasitic pathogens but not to the common viral pathogens

Efficacy of the Pentavalent Rotavirus Vaccine, RotaTeq (RV5), Between Doses of a 3-Dose Series and With Less Than 3 Doses (Incomplete Regimen)

Post-hoc analyses of the Rotavirus Efficacy and Safety Trial (RES T) were conducted to determine whether the pentavalent rotavirus vaccine (RV5) confers early protection against rotavirus gastroenteritis (RVGE) before completion of the 3-dose regimen. To evaluate the efficacy of RV5 between doses in reducing the rates of RVGE-related hospitalizations and emergency department (ED) visits in infants who ultimately received all 3 doses of RV5/placebo, events occurring from 2 weeks after the first and second doses to receipt of the subsequent dose (Analysis A) and events occurring from 2 weeks after the first and second doses to 2 weeks after the subsequent dose (Analysis B) were analyzed. In Analysis A, RV5 reduced the rates of combined hospitalizations and ED visits for G1-G4 RVGE or RVGE regardless of serotype between doses 1 and 2 by 100% [95% confidence interval (CI): 72-100%] or 82% (95% CI: 39-97%), respectively, and between doses 2 and 3, RV5 reduced the rates of combined hospitalizations and ED visits for G1-G4 RVGE or RVGE regardless of serotype by 91% (95% CI: 63-99%) or 84% (95% CI: 54-96%), respectively. Similar rate reductions were observed in Analysis B. These data suggest that RV5 provides a high level of protection between doses against hospitalizations and ED visits for RVGE starting as early as 14 days after the first dose

Caliciviruses and Foodborne Gastroenteritis, Chile

Human caliciviruses caused 45% of 55 gastroenteritis outbreaks occurring in Santiago, Chile, during 2000–2003. Outbreaks affected ≤99 persons, occurred most commonly in the home, and were associated with seafood consumption. Thirteen outbreak strains sequenced were noroviruses, including 8 GII, 2 GI, and 3 belonging to a novel genogroup

Human Caliciviruses Are a Significant Pathogen of Acute Sporadic Diarrhea in Children of Santiago, Chile

Human caliciviruses (HuCVs) are increasingly recognized as common pathogens that cause acute sporadic diarrhea in children; however, regional antigenic and genetic diversity complicate detection techniques. Stool samples from children seeking medical attention in 2 outpatient clinics, a large emergency department, and 2 hospital wards were evaluated for HuCVs by reverse transcription–polymerase chain reaction, using primers based on a conserved sequence of the polymerase region of a previously sequenced Chilean strain. HuCVs were detected in 53 (8%) of 684 children 1 month to 5 years of age (mean, 13 months). Detection occurred year-round without a clear seasonal peak, and detection frequency declined from 16% in 1997 to 2% in 1999. The decline may have been due to a change in virus genotype. HuCVs are a significant pathogen of acute sporadic diarrhea in Chilean children, and continuous characterization of genetic diversity will be crucial for appropriate detection.Financial support: Chilean Fondo de Desarrollo de Ciencia y Teconologı´a (1980895)

Novel recombinant norovirus causing outbreaks of gastroenteritis in Santiago, Chile

Capsid and polymerase (RdRp) genes of 13 norovirus outbreak strains from Chile were compared. The genes sequences were discordant for five strains, and recombination was confirmed for two of them by amplification of a 1,360-bp gene segment containing a fragment of both genes. These strains belonged to a novel genogroup by RdRp sequence and to genogroup GII/3 by capsid sequence. Determining the clinical and epidemiological impact of human calicivirus recombination will require future studies

Rotavirus Antigenemia in Children Is Associated with Viremia

BACKGROUND: Antigenemia is commonly detected in rotavirus-infected children. Although rotavirus RNA has been detected in serum, definitive proof of rotavirus viremia has not been shown. We aimed to analyze a defined patient population to determine if infectious virus could be detected in sera from children with rotavirus antigenemia. METHODS AND FINDINGS: Serum samples obtained upon hospitalization from children with gastroenteritis (57 stool rotavirus-positive and 41 rotavirus-negative), children with diagnosed bronchiolitis of known (n = 58) or unknown (n = 17) viral etiology, children with noninfectious, nonchronic conditions (n = 17), and healthy adults (n = 28) were tested for rotavirus antigen by enzyme immunoassay (EIA). Results of serum antigen testing were assessed for association with clinical and immunological attributes of the children. Rotavirus antigenemia was detected in 90% (51/57) of children with rotavirus-positive stools, in 89% (8/9) of children without diarrhea but with rotavirus-positive stools, in 12% (2/17) of children with bronchiolitis of unknown etiology without gastroenteritis, and in 12% (5/41) of children with gastroenteritis but with rotavirus-negative stools. Antigenemia was not detected in sera from children with noninfectious nonchronic conditions, children with bronchiolitis of known etiology and no gastroenteritis, or healthy adults. Neither age nor timing of serum collection within eight days after onset of gastroenteritis significantly affected levels of antigenemia, and there was no correlation between antigenemia and viral genotype. However, there was a negative correlation between serum rotavirus antigen and acute rotavirus-specific serum IgA (r = −0.44, p = 0.025) and IgG (r = −0.40, p = 0.01) titers. We examined 11 antigen-positive and nine antigen-negative sera for infectious virus after three blind serial passages in HT-29 cells using immunofluorescence staining for rotavirus structural and nonstructural proteins. Infectious virus was detected in 11/11 (100%) sera from serum antigen-positive children and in two out of nine (22%) sera samples from antigen-negative children (p = 0.002). CONCLUSIONS: Most children infected with rotavirus are viremic. The presence of viremia is directly related to the detection of antigenemia and is independent of the presence of diarrhea. Antigenemia load is inversely related to the titer of antirotavirus antibody in the serum. The finding of infectious rotavirus in the blood suggests extraintestinal involvement in rotavirus pathogenesis; however, the impact of rotavirus viremia on clinical manifestations of infection is unknown

A Model for the Roll-Out of Comprehensive Adult Male Circumcision Services in African Low-Income Settings of High HIV Incidence: The ANRS 12126 Bophelo Pele Project

Bertrand Auvert and colleagues describe the large-scale roll-out of adult male circumcision through a program in South Africa

Crop Updates 2002 - Geraldton

This session covers twenty seven papers from different authors: 1. Taking the Why out of Wyalkatchem – the new widely adapted wheat variety, Steve Penny Jr, Department of Agriculture 2. Future wheat varieties, Robin Wilson, Iain Barclay,Robyn McLean, Robert Loughman, Jenny Garlinge, Bill Lambe, Neil Venn and Peter Clarke Department of Agriculture 3. Maximising wheat variety performance through agronomic management, Wal Anderson, Raffaele Del Cima, James Bee, Darshan Sharma, Sheena Lyon, Melaine Kupsch, Mohammad Amjad, Pam Burgess, Veronika Reck, Brenda Shackley, Ray Tugwell, Bindi Webb and Steve Penny Jr Department of Agriculture 4. Cereal rust update 2002 – a new stem rust on Camm wheat, Robert Loughman1and Robert Park2 1Department of Agriculture, 2University of Sydney 5. Influence of nutrition and environmental factors on seed vigour in wheat, Darshan Sharma, Wal Anderson and Daya Patabendige, Department of Agriculture 6. Cereal aphids and direct feeding damage to cereals, Phil Michael, Department of Agriculture 7. A decision support system for control of aphids and BYDV in cereal crops, Debbie Thackray, Jenny Hawkes and Roger Jones, Department of Agriculture and Centre for Legumes in Mediterranean Agriculture 8. Summary of 2001 weather and seasonal prospects for 2002, David Stephens, Department of Agriculture 9. Towards a management package for grain protein in lupins, Bob French, Senior Research Officer, Department of Agriculture 10. Lupin genotypes respond differently to potash, Bob French and Laurie Wahlsten, Senior Research Officer and Technical Officer, Department of Agriculture 11. Time of harvest for improved seed yield of pulses, G. Riethmuller and B. French, Department of Agriculture 12. Comparing the phosphorus requirement of field pea and wheat, M. Bolland and P. White, Department of Agriculture Western Australia 13. Field pea variety evaluation, T. Khan, Department of Agriculture Western Australia 14. Diamondback moth (DBM) in canola, Kevin Walden, Department of Agriculture 15. WA blackleg resistance ratings on canola varieties for 2002, Ravjit Khangura, Martin J. Barbetti and Graham Walton, Department of Agriculture 16. The effect of single or multiple spray treatments on the control of Diamondback moth (Plutella xylostella) and yield of canola at Wongan Hills, Françoise Berlandier, Paul Carmody and Christiaan Valentine, Department of Agriculture 17. Perennial pastures in annual cropping systems: Lucerne and beyond, Roy Latta and Keith Devenish, Department of Agriculture 18. Nutrition in 2002: Decisions to be made as a result of last season, Bill Bowden,Department of Agriculture 19. Profitability of deep banding lime, Michael O\u27Connell, Chris Gazey and David Gartner, Department of Agriculture 20. Economic comparisons of farming systems for the medium rainfall northern sandplain, Caroline Peek and David Rogers, Department of Agriculture 21. The use of Twist Fungus as a biosecurity measure against Annual Ryegrass Toxicity (ARGT), Greg Shea, GrainGuard Coordinator and George Yan, Biological and Resource Technology 22. Major outcomes from IWM demonstration sites, Alexandra Douglas, Department of Agriculture 23. Understanding the weed seed bank life of important agricultural weeds, Sally Peltzer and Paul Matson, Department of Agriculture 24. Seeding rate, row spacing and herbicides for weed control, David Minkey, Department of Agriculture 25. Improving weed control in grazed pastures using legumes with low palatability, Clinton Revell and Giles Glasson, Department of Agriculture, Dean Thomas, Faculty of Agriculture, University of Western Australia 26. Group F resistant wild radish: What’s new? Aik Cheam1, Siew Lee1and Mike Clarke2, 1Department of Agriculture WA, 2Aventis Crop Science 27. Knockdown herbicides do not reliably kill small grass weeds, Peter Newman and Glenn Adam, Department of Agricultur

Helicobacter pylori versus the Host: Remodeling of the Bacterial Outer Membrane Is Required for Survival in the Gastric Mucosa

Modification of bacterial surface structures, such as the lipid A portion of lipopolysaccharide (LPS), is used by many pathogenic bacteria to help evade the host innate immune response. Helicobacter pylori, a gram-negative bacterium capable of chronic colonization of the human stomach, modifies its lipid A by removal of phosphate groups from the 1- and 4′-positions of the lipid A backbone. In this study, we identify the enzyme responsible for dephosphorylation of the lipid A 4′-phosphate group in H. pylori, Jhp1487 (LpxF). To ascertain the role these modifications play in the pathogenesis of H. pylori, we created mutants in lpxE (1-phosphatase), lpxF (4′-phosphatase) and a double lpxE/F mutant. Analysis of lipid A isolated from lpxE and lpxF mutants revealed lipid A species with a 1 or 4′-phosphate group, respectively while the double lpxE/F mutant revealed a bis-phosphorylated lipid A. Mutants lacking lpxE, lpxF, or lpxE/F show a 16, 360 and 1020 fold increase in sensitivity to the cationic antimicrobial peptide polymyxin B, respectively. Moreover, a similar loss of resistance is seen against a variety of CAMPs found in the human body including LL37, β-defensin 2, and P-113. Using a fluorescent derivative of polymyxin we demonstrate that, unlike wild type bacteria, polymyxin readily associates with the lpxE/F mutant. Presumably, the increase in the negative charge of H. pylori LPS allows for binding of the peptide to the bacterial surface. Interestingly, the action of LpxE and LpxF was shown to decrease recognition of Helicobacter LPS by the innate immune receptor, Toll-like Receptor 4. Furthermore, lpxE/F mutants were unable to colonize the gastric mucosa of C57BL/6J and C57BL/6J tlr4 -/- mice when compared to wild type H. pylori. Our results demonstrate that dephosphorylation of the lipid A domain of H. pylori LPS by LpxE and LpxF is key to its ability to colonize a mammalian host