Molecular epidemiology of norovirus infections in sporadic cases of viral gastroenteritis among children in Northern Italy

Surveillance of norovirus infections in sporadic cases of pediatric gastroenteritis admitted to a main hospital in Northern Italy during a full-year period (2002) showed that noroviruses (10.4%) were the second most common causative viral agent, following rotaviruses (21.1%), and noroviruses (81%) were mostly implicated in mixed infections. The epidemic period of norovirus was September-December, with September and November as months of major prevalence (33.3 and 38.5%, respectively). Six distinct norovirus genotypes were detected (GI.7, GII.1, GII.2, GII.4, GII.7, GII, not assigned named GIIb), and the predominant genotype was GII.4. A "new GII.4 2002 variant" accounted for 82.9% of total strains. Since the severity of norovirus symptoms does not usually require admission to hospital, the burden of norovirus disease in the general children population may be much higher than that suggested by the present hospital-based investigation.     

Emerging GII.4 norovirus variants affect children with diarrhea in Palermo,Italy in 2006

Although the genetic/antigenic heterogeneity of human noroviruses (NoVs) is impressive, a few genogroup II strains of genotype 4 (GII.4) are dominant worldwide. GII.4 NoVs evolve rapidly and in the last 15 years six epidemic variants have been identified. In 2005–2006, surveillance of sporadic viral gastroenteritis in children in Palermo, Italy, resulted in the detection of NoV strains in 20.9% of the patients admitted to hospital. By restriction fragment length polymorphism (RFLP) and sequence analysis of region A in the RNA‐dependent RNA‐polymerase (RdRp) gene, 59 NoV strains were successfully characterized. Eighty‐one percent of the strains were characterized as GII.4, 14% as GIIb/Hilversum and 5% as GI.1. Phylogenetic analysis of region A and of the ORF1/ORF2 overlapping region of the GII.4 strains recovered in Palermo in the years 2002–2006 revealed the sequential emergence of four variants, GII.4 2002, 2004, 2006a, and 2006b. The variant GII.4 2006a was detected in June and July, 2006, while the variant 2006b first appeared in August, 2006, becoming predominant thereafter. Based on these findings, the dynamics of replacement and circulation of the GII.4 NoV variants in Italy in 2005–2006 appear to have matched the temporal pattern observed in Europe during the same period. J. Med. Virol. 81:139–145, 2009. © 2008 Wiley‐Liss, Inc.     

Emergence of Norovirus GII.4 variants in acute gastroenteritis outbreaks in South Korea between 2006 and 2013

BackgroundNew emerging strains of noroviruses (NoVs) often increase acute gastroenteritis (AGE) outbreaks worldwide.ObjectiveWe analyzed the epidemiological features and genotypic patterns of NoVs in AGE outbreaks.Study designTo elucidate the public health impact of NoVs during AGE outbreaks in South Korea, a molecular and epidemiological investigation was performed with 318 AGE outbreaks reported from the Gyeonggi province of South Korea during the period from 2006 to 2013.ResultsNoVs were associated with 102 (32.1%) of the AGE outbreaks. Epidemiological data revealed that the majority of NoV outbreaks were in the student group (47.1%), and the majority of AGE patients were identified in schools (68.8%). NoV genogroup (G) II strains were associated with 94 (92.2%) of the NoV outbreaks, and GII.4 strains were predominantly associated with 57.6% (n = 49) of NoV GII outbreaks. Four GII.4 variants (2006b, 2007, 2009 and 2012 variants) emerged and showed different contributions to NoV outbreak activity. The 2006b variant was predominantly associated with NoV outbreaks during the early years of the study period, and was subsequently displaced by the New Orleans 2009 variant, and most recently by the Sydney 2012 variant. In addition, the GII.2, GII.14, and GII.17 strains have recently been often associated with NoV AGE outbreaks.ConclusionsThe emergence of new NoV GII.4 variants significantly affected the NoV outbreak activity in South Korea during the period from 2006 to 2013. The surveillance for new emerging strains affecting NoV outbreak activity should be intensified to develop an adequate policy to prevent further NoV outbreaks.     

Elisa test system with monoclonal antibodies to human IgG4 for the detection of allergen-specific antibodies in pollinosis

G. N. Gabrichevskii Moscow Research Institute of Epidemiology and Microbiology. Institute. of Experimental Cardiology, All-Union Cardiologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. I. Vorob'ev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 108, No. 11, pp. 574–577, November, 1989.     

Genotype distribution of norovirus around the emergence of Sydney_2012 and the antigenic drift of contemporary GII.4 epidemic strains

BackgroundThe pattern of epochal evolution of NoV is ongoing, while novel GII.4 variants emerge and cause new pandemics. Since, the emergence in March 2012, Sydney_2012 had replaced GII.4-2009 as the primary NoV strain in most countries in the northern hemisphere by November 2012.ObjectivesTo determine the genotype distribution around the emergence of Sydney_2012 and to investigate the underlying evolution mechanisms of the contemporary GII.4 strains.Study designFrom January 2012 to December 2013, molecular epidemiology of norovirus in 846 adults (≥16 years) in Shanghai were conducted. The VP1 proteins of the contemporary GII.4 strains (Den_Haag_2006b, New_Orleans_2009 and Sydney_2012) were expressed in vitro and purified. Receptor binding patterns of these three epidemic strains were determined through histo-blood group antigen (HBGA) binding assays. Convalescent serum from patients infected with GII.4 epidemic strains were employed to investigate the role of antigenic drift in the persistence of GII.4 epidemic strains through receptor-binding blockade assays.ResultsEpidemiological studies revealed that Sydeny_2012 has completely replaced Den_Haag_2006b and New_Orleans_2009 and has been the dominant circulating strain in Shanghai since its emergence in October 2012. Interestingly, Den_Haag_2006b and New_Orleans_2009 have been co-circulating in Shanghai before the emergence of Sydeny_2012. The contemporary GII.4 epidemic norovirus strains displayed commonly high tropism to the histo-blood group antigen receptors, whereas Sydeny_2012 was antigenically different from Den_Haag_2006b and New_Orleans_2009.ConclusionsAntigenic drift, rather than receptor switch, played a key role in the emergence and spreading of Sydney_2012. The contemporary GII.4 strains were evolving via epochal evolution without altered ligand binding profiles.     

IgG4‐related disease manifesting the gastric wall thickening

IgG4‐related disease (IgG4‐RD) is a recently designated disease entity and its full picture has not yet been elucidated. Here, we report an unusual case of a patient with gastric wall thickening secondary to IgG4‐RD. A 68‐year‐old male visited our hospital with itchy skin lesions and an episode of organizing pneumonia. On the suspicion of malignancy‐associated skin lesions, computed tomography (CT) was performed. The CT revealed prominent thickening of the gastric wall. Due to the possibility of malignancy, the patient underwent distal gastrectomy. Histopathological examination showed fibrosis of the submucosa and prominent thickening of the muscularis propria. Most of infiltrating cells were IgG4‐positive plasma cells. Post‐operative blood test revealed significantly high serum levels of total IgG and IgG4. Based on these histological features, the patient was given a definitive diagnosis of IgG4‐RD. Further accumulation of cases like the present case that develop IgG4‐RD with rare manifestations would lead to the elucidation of pathogenesis.     

Clinical and molecular epidemiology of norovirus infection in childhood diarrhea in China

A prospective investigation was carried out among pediatric outpatients and inpatients with acute non‐dysenteric diarrhea between August, 2008 and July, 2009 in Shanghai, Hangzhou, Chongqing, and Tianjin, China. One step real‐time RT‐PCR was used for detection of norovirus (NoV) genogroups I and II (GI, GII). The NoV genotypes were classified based on partial capsid sequences. Rotavirus (RV) was detected in parallel. Among 4,123 fecal samples from outpatients, 1,067 (25.9%) were NoV‐positive, of which 1,051 (98.5%) belonged to GII and 1,309 (31.7%) were RV‐positive. In the inpatient group (n = 317), 25.6% were NoV‐positive and 41.6% were RV‐positive. Four hundred and fifty‐one out of 1,067 NoV‐positive strains were sequenced and genotyped and 6 typed strains were GI (3 GI.3, 2 GI.5, 1 GI.4) and 445 typed strains were GII. GII strains clustered into nine genotypes including GII.4 2006b (69.2%), the only GII.4 variant identified in this study, followed by GII.3 (23.8%), GII.6 (3.6%), GII.12 (1.3%), GII.2 (0.9%), GII.13 (0.4%), GII.14 (0.2%), GII.7 (0.2%), and GII.16 (0.2%). A peak of NoV infections was observed during the cold season in Tianjin, while NoV activity was higher between late summer and autumn and lower during winter in Shanghai, Hangzhou, and Chongqing. NoV is a common causative agent of childhood diarrhea in China and the seasons of NoV‐associated diarrhea varies between regions. The results show that NoV GII.4 2006b was the predominant strain circulating in China between 2008 and 2009. J. Med. Virol. 84:145–151, 2011. © 2011 Wiley Periodicals, Inc.     

IgG4‐related disease: review of the histopathologic features,differential diagnosis,and therapeutic approach

Immunoglobulin G4‐related disease (IgG4‐RD) is an uncommon disorder that demonstrates characteristic clinicopathologic features including sclerosing lesions with storiform fibrosis, increased IgG4+ plasma cells with an increased IgG4+/IgG+ plasma cell ratio, obliterative phlebitis, and often an increased serum IgG4 level. This review summarizes the characteristic histopathologic and clinical features of IgG4‐RD with detailed discussion of the histopathologic characteristics of the most commonly involved anatomic sites. We also present recent advances in our understanding of the pathophysiologic mechanisms of IgG4‐RD and discuss updates on the treatment, prognosis, and outcomes of this rare disease, including discussion of the possible association between IgG4‐RD and malignancy.     

Increase of allergen‐specific immunoglobulin E antibodies from 1973 to 1994 in a Finnish population and a possible relationship to Helicobacter pylori infections1

Background The prevalence of atopic diseases – hayfever, asthma and eczema – has increased over the past decades. The increase may be associated with decreased rates of infections such as measles, hepatitis A, tuberculosis, toxoplasmosis, and, as recently suggested, Helicobacter pylori gastritis. Objective Since the increase of atopy has been mainly based on clinical studies, we wanted to study the prevalence of allergen‐specific Immunoglobulin (Ig)E antibodies in two cross‐sectional, adult population‐based serum samples two decades apart. Since the sera had been tested for H. pylori antibodies, we also had a chance to look for a possible relationship between these two findings. Methods We determined the prevalence rate of allergen‐specific serum IgE antibodies against birch and timothy pollen, and cat and dog epithelium allergens by the radioallergosorbent test in a 15–54‐years‐old Finnish population using 326 sera collected in 1973 and 319 sera collected in 1994 from randomly selected subjects. Results From 1973 to 1994 allergen‐specific IgE prevalence rates and IgE antibody levels rose. In 1994, the prevalence rate of positive findings in 15–24‐year‐old population had increased from 11 to 38% (3.5‐fold increase, P = 0.0001, OR 5.12, CI 95% 2.32–11.3). In older 10‐year age groups similar trends did not reach significance, but the overall change was significant with all three cut‐off levels of allergen‐specific IgE analysed. The percentage of IgE‐positive persons rose mainly in the subgroup with no H. pylori antibodies. In 1994 21% of the H. pylori‐negative subjects had IgE antibodies compared with 5% of the H. pylori‐positive subjects (in 1973 11% in both subgroups). Conclusions IgE‐based evidence for an increase in IgE‐mediated allergy was uncovered. The increase occurred mainly in the subgroup with no antibodies to H. pylori, which support the hypothesis that H. pylori could be one of the microbes counteracting atopy.     

Molecular epidemiology of norovirus gastroenteritis outbreaks in New Zealand from 2002-2009

Noroviruses are the most common cause of acute non-bacterial gastroenteritis outbreaks worldwide, including New Zealand. New Zealand has a population of 4.4 million, which allows for centralized outbreak surveillance and a Norovirus Reference Laboratory, which facilitates efficient diagnosis, surveillance, and tracking of norovirus outbreaks. Norovirus outbreak strains are identified, sequenced, and compared with international reference strains. Between January 2002 and December 2009, 1,206 laboratory-confirmed norovirus outbreaks were recorded. The predominant outbreak settings were healthcare institutions for the elderly and acute care patients. Other outbreak settings included catering establishments, cruise ships, homes, community events, school camps, child-related settings, and consumption of contaminated shellfish. Of the 1,206 outbreaks, 105 (8.7%) were caused by norovirus genogroup I (GI) strains, 1,085 (89.9%) were caused by genogroup II (GII) strains, and both GI and GII strains were detected in 9 (0.8%) outbreaks. The genogroup was not identified in 7 (0.6%) outbreaks. A range of norovirus genotypes, including GI genotypes 1-6, GII genotypes 2-8, and GII.12, were associated with these outbreaks. The predominant genotype was GII.4, which was identified in 825 (68.4%) outbreaks. Norovirus GII.4 variant strains, including 2002 (Farmington Hills), 2004 (Hunter), 2006a (Laurens, Yerseke), 2006b (Minerva), and 2010 (New Orleans) implicated in overseas outbreaks also occurred in New Zealand, providing evidence of global spread.     

Clinicopathological differential diagnosis of IgG4‐related disease: A historical overview and a proposal of the criteria for excluding mimickers of IgG4‐related disease

IgG4‐related disease (RD) is a relatively new entity, which was first proposed in 2001. Since then, clinical and pathological characteristics of the disease have been investigated. As IgG4‐RD has been studied extensively, the diagnostic criteria for IgG4‐RD of each organ and the comprehensive diagnostic criteria for IgG4‐RD have also been developed. However, one of the biggest challenges in the field is distinguishing between IgG4‐RD and mimickers, which show overlapping features with IgG4‐RD. It is now known that some non‐IgG4‐RDs may meet the diagnostic criteria of IgG4‐RD and can be misdiagnosed as IgG4‐RD. However, accurate diagnosis is crucial, as the treatments for IgG4‐RD and those for other diseases that may be misdiagnosed as IgG4‐RD are different. This prompted us to create and propose comprehensive exclusion criteria for IgG4‐RD. In this review, we have described the comprehensive exclusion criteria for IgG4‐RD, with a historical overview of the disease. These exclusion criteria were recently created by the Research Program for Intractable Disease of the Ministry of Health, Labor, and Welfare of Japan, All Japan IgG4 team, to support correct and accurate diagnosis of IgG4‐RD.