Browsing by Subject "GASTROENTERITIS"

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  • Lienemann, Taru; Kyyhkynen, Aino; Halkilahti, Jani; Haukka, Kaisa; Siitonen, Anja (2015)
    Background: Salmonella enterica spp. enterica serotype Typhimurium (STM) is the most common agent of domestically acquired salmonellosis in Finland. Subtyping methods which allow the characterization of STM are essential for effective laboratory-based STM surveillance and for recognition of outbreaks. This study describes the diversity of Finnish STM isolates using phage typing, antimicrobial susceptible testing, pulsed-field gel electrophoresis (PFGE) and multilocus variable-number tandem repeat analysis (MLVA), and compares the discriminatory power and the concordance of these methods. Results: A total of 375 sporadic STM isolates were analysed. The isolates were divided into 31 definite phage (DT) types, dominated by DT1 (47 % of the isolates), U277 (9 % of the isolates) and DT104 (8 % of the isolates). Of all the isolates, 62 % were susceptible to all the 12 antimicrobials tested and 11 % were multidrug resistant. Subtyping resulted in 83 different XbaI-PFGE profiles and 111 MLVA types. The three most common XbaI-PFGE profiles (STYM1, STYM7 and STYM8) and one MLVA profile with three single locus variants accounted for 56 % and 49 % of the STM isolates, respectively. The studied isolates showed a genetic similarity of more than 70 % by XbaI-PFGE. In MLVA, 71 % of the isolates lacked STTR6 and 77 % missed STTR10p loci. Nevertheless, the calculated Simpson's diversity index for XbaI-PFGE was 0.829 (95 % CI 0.792-0.865) and for MLVA 0.867 (95 % CI 0.835-0.898). However, the discriminatory power of the 5-loci MLVA varied among the phage types. The highest concordance of the results was found between XbaI-PFGE and phage typing (adjusted Wallace coefficient was 0.833 and adjusted Rand coefficient was 0.627). Conclusions: In general, the calculated discriminatory power was higher for genotyping methods (MLVA and XbaI-PFGE) than for phenotyping methods (phage typing). Overall, comparable diversity indices were calculated for PFGE and MLVA (both DI > 0.8). However, MLVA was phage type dependent providing better discrimination of the most common phage types. Furthermore, 5-loci MLVA was a less laborious method and easier to interpret than XbaI-PFGE. Thus, the laboratory-based surveillance of the Finnish human STM infections has been conducted with a combination of phage typing, antimicrobial susceptibility testing and 5-loci MLVA since January 2014.
  • Rolfes, M. C.; Sriaroon, P.; Saldana, B. J. Davila; Dvorak, C. C.; Chapdelaine, H.; Ferdman, R. M.; Chen, K.; Jolles, S.; Patel, N. C.; Kim, Y. J.; Tarrant, T. K.; Martelius, T.; Seppanen, M.; Joshi, A. Y. (2019)
    Objective: Predictive factors associated with clinical outcomes of chronic norovirus infection (CNI) in primary immunodeficiency diseases (PIDD) are lacking. Method: We sought to characterize CNI using a multi-institutional cohort of patients with PIDD and CNI using the Clinical Immunology Society's CIS-PIDD Listserv e-mail group. Results: Thirty-four subjects (21 males and 13 females) were reported from centers across North America, Europe, and Asia. All subjects were receiving high doses (median IgG dose: 1200 mg/kg/month) of supplemental immunoglobulin therapy. Fifty-three percent had a complete absence of B cells (median B-cell count 0; range 0-139 cells/mu L). Common Variable Immune Deficiency (CVID) subjects manifested a unique phenotype with B-cell lymphopenia, non O+ blood type, and villous atrophy (logistic regression model, P = 0.01). Five subjects died, all of whom had no evidence of villous atrophy. Conclusion: While Norovirus (NoV) is thought to replicate in B cells, in this PIDD cohort of CNI, B-cell lymphopenia was common, indicating that the presence of B lymphocytes is not essential for CNI. (C) 2018 Published by Elsevier Inc.
  • Oristo, Satu; Rönnqvist, Maria; Aho, Mika; Sovijärvi, Ava; Hannila-Handelberg, Tuula; Horman, Ari; Nikkari, Simo; Kinnunen, Paula M.; Maunula, Leena (2017)
    This study investigated the presence of norovirus and adenovirus, especially enteric adenovirus, on the environmental surfaces (n = 481) and military conscripts' hands (n = 109) in two Finnish garrisons (A and B) in 2013 and 2014. A questionnaire study was conducted to reveal possible correlations between viral findings on the conscripts' hands and their acute gastroenteritis symptoms. In addition to the swab samples, 14 fecal samples were obtained for viral analysis. In total, norovirus was present in 9.0 % of the surface swabs in 2013, whereas enteric adenovirus was present in 0.0 % and non-enteric adenovirus in 9.4 %. In the same year, 2.6 % of the hand swabs contained norovirus, 2.6 % enteric adenovirus, and 40.3 % non-enteric adenovirus. Norovirus GI.6 was continually detected on the surfaces of garrison A, and identical virus was detected in some of the fecal samples. In garrison B, two slightly different norovirus GII.4 strains were present on the surfaces. The questionnaires revealed no recent acute gastroenteritis cases in garrison A, but in garrison B, where the norovirus-positive hand swabs were collected, 30.6 % of the conscripts reported of recent symptoms. In 2014, norovirus was rarely detected, but adenovirus was again frequently present, both on the surfaces and hands. Taken together, our results suggest that gastroenteritis outbreaks occurred in 2013, but not in 2014. Due to the low number of hand swabs positive for enteric viruses, no conclusions about associations between viral findings and gastroenteritis symptoms could be drawn. This study increased our understanding of the possible transmission of viruses via contaminated environment and hands.
  • Malm, Maria; Hyoty, Heikki; Knip, Mikael; Vesikari, Timo; Blazevic, Vesna (2019)
    Most of the research effort to understand protective immunity against norovirus (NoV) has focused on humoral immunity, whereas immunity against another major pediatric enteric virus, rotavirus (RV), has been studied more thoroughly. The aim of this study was to investigate development of cell-mediated immunity to NoV in early childhood. Immune responses to NoV GI.3 and GII. 4 virus-like particles and RV VP6 were determined in longitudinal blood samples of 10 healthy children from three months to four years of age. Serum IgG antibodies were measured using enzyme-linked immunosorbent assay and production of interferon-gamma by peripheral blood T cells was analyzed by enzyme-linked immunospot assay. NoV-specific T cells were detected in eight of 10 children by the age of four, with some individual variation. T cell responses to NoV GII.4 were higher than those to GI.3, but these responses were generally lower than responses to RV VP6. In contrast to NoV-specific antibodies, T cell responses were transient in nature. No correlation between cell-mediated and antibody responses was observed. NoV exposure induces vigorous T cell responses in children under five years of age, similar to RV. A role of T cells in protection from NoV infection in early childhood warrants further investigation.
  • Summa, M.; Henttonen, H.; Maunula, L. (2018)
    Human noroviruses (HuNoVs) are one of the leading global causes of diarrhoeal diseases and are transmitted mainly from person to person but also through contaminated food, water and fomites. The possible zoonotic nature of NoVs has occasionally been discussed, although the viruses are generally considered to be host-species-specific. We investigated whether wild birds and rodents could serve as carriers of HuNoVs, thereby transmitting the virus to humans directly or indirectly by contaminating foods. All samples, 115 avian and 100 rat faeces collected in springs 2009-2013 from dump sites, and 85 faeces from yellow-necked mice trapped in late autumn 2008 and 2009 after the rodents entered human settlements due to the first night frosts, were screened for HuNoV using real-time reverse transcription PCR. HuNoVs were detected in 31 (27%) faecal samples of wild birds, in two (2%) faecal samples of rats and in no samples of mice. Most (25) of the positive bird samples and both rat samples contained genogroup II, and six positive bird samples contained genogroup I HuNoV. The avian species shedding faeces containing HuNoVs were identified as gulls and crows using DNA barcoding. Our results show that wildlife, birds and rats in particular, is capable of spreading HuNoVs in the environment.
  • NoroNet; van Beek, Janko; Al-Hello, Haider; Maunula, Leena (2018)
    Background The development of a vaccine for norovirus requires a detailed understanding of global genetic diversity of noroviruses. We analysed their epidemiology and diversity using surveillance data from the NoroNet network. Methods We included genetic sequences of norovirus specimens obtained from outbreak investigations and sporadic gastroenteritis cases between 2005 and 2016 in Europe, Asia, Oceania, and Africa. We genotyped norovirus sequences and analysed sequences that overlapped at open reading frame (ORF) 1 and ORF2. Additionally, we assessed the sampling date and country of origin of the first reported sequence to assess when and where novel drift variants originated. Findings We analysed 16 635 norovirus sequences submitted between Jan 1, 2005, to Nov 17, 2016, of which 1372 (8.2%) sequences belonged to genotype GI, 15 256 (91.7%) to GII, and seven ( Interpretation Continuous changes in the global norovirus genetic diversity highlight the need for sustained global norovirus surveillance, including assessment of possible immune escape and evolution by recombination, to provide a full overview of norovirus epidemiology for future vaccine policy decisions.
  • Harris, Vanessa; Ali, Asad; Fuentes, Susana; Korpela, Katri; Kazi, Momin; Tate, Jacqueline; Parashar, Umesh; Wiersinga, W. Joost; Giaquinto, Carlo; de Weerth, Carolina; de Vos, Willem M. (2018)
    Rotavirus (RV) is the leading cause of diarrhea-related death in children worldwide and ninety-five percent of rotavirus deaths occur in Africa and Asia. Rotavirus vaccines (RVV) can dramatically reduce RV deaths, but have low efficacy in low-income settings where they are most needed. The intestinal microbiome may contribute to this decreased RVV efficacy. This pilot study hypothesizes that infants' intestinal microbiota composition correlates with RVV immune responses and that RVV responders have different gut microbiota as compared to non-responders. We conducted a nested, matched case-control study comparing the pre-vaccination intestinal microbiota composition between 10 6-week old Pakistani RVV-responders, 10 6-week old Pakistani RVV non-responders, and 10 healthy Dutch infants. RVV response was defined as an Immunoglobulin A of >= 20 IU/mL following Rotarix (TM)(RV1) vaccination in an infant with aprevaccination IgA RV1 response correlated with a higher relative abundance of bacteria belonging to Clostridium cluster XI and Proteobacteria, including bacteria related to Serratia and Escherichia coli. Remarkably, abundance of these Proteobacteria was also significantly higher in Dutch infants when compared to RV1-non-responders in Pakistan. This small but carefully matched study showed the intestinal microbiota composition to correlate with RV1 seroconversion in Pakistan infants, identifying signatures shared with healthy Dutch infants.
  • Åberg, Fredrik; Savikko, Johanna; Anttila, Veli-Jukka; Mäkisalo, Heikki (2018)
    In an intestinal transplant patient under triple immunosuppression therapy with tacrolimus levels > 10 ng/L, a 2-day oral immunoglobulin therapy given as treatment for chronic norovirus infection was temporally closely associated with the development of severe steroid-resistant acute graft rejection, thus suggesting that oral immunoglobulin might be able to promote a rejection response.
  • Keto-Timonen, Riikka; Markkula, Annukka; Halkilahti, Jani; Huttunen, Reetta; Räsänen, Sirpa; Salmenlinna, Saara; Heikkilä, Anne; Puisto, Mia; Närhinen, Maria; Hakkinen, Marjaana; Korkeala, Hannu; Jalava, Katri (2019)
    In November 2016, an elderly patient was diagnosed with Listeria monocytogenes bacteremia in Finland. Grocery store loyalty card records and microbiological investigation of foods found in the home fridge and freezer of the patient revealed commercial, modified-atmosphere packaged meatballs as the source of the infection. Investigation of the meatball production plant revealed that the floor drain samples were contaminated with the same L. monocytogenes strain as those isolated from the patient and meatballs. Ready-to-eat meatballs were likely contaminated after heat treatment from the production environment before packaging. Long-term cold storage, modified-atmosphere conditions, and the absence of competing bacteria presumably enhanced the growth of L. monocytogenes. We recommend that collection of shopping details and home fridge and freezer sampling should be part of surveillance of all cases of L. monocytogenes infections to complement information obtained from in-depth interviews.
  • Harris, Vanessa C.; Armah, George; Fuentes, Susana; Korpela, Katri E.; Parashar, Umesh; Victor, John C.; Tate, Jacqueline; de Weerth, Carolina; Giaquinto, Carlo; Wiersinga, Willem Joost; Lewis, Kristen D. C.; de Vos, Willem M. (2017)
    Background. Rotavirus (RV) is the leading cause of diarrhea-related death in children worldwide and 95% of RV-associated deaths occur in Africa and Asia where RV vaccines (RVVs) have lower efficacy. We hypothesize that differences in intestinal microbiome composition correlate with the decreased RVV efficacy observed in poor settings. Methods. We conducted a nested, case-control study comparing prevaccination, fecal microbiome compositions between 6week old, matched RVV responders and nonresponders in rural Ghana. These infants' microbiomes were then compared with 154 age-matched, healthy Dutch infants' microbiomes, assumed to be RVV responders. Fecal microbiome analysis was performed in all groups using the Human Intestinal Tract Chip. Results. We analyzed findings in 78 Ghanaian infants, including 39 RVV responder and nonresponder pairs. The overall microbiome composition was significantly different between RVV responders and nonresponders (FDR, 0.12), and Ghanaian responders were more similar to Dutch infants than nonresponders (P =.002). RVV response correlated with an increased abundance of Streptococcus bovis and a decreased abundance of the Bacteroidetes phylum in comparisons between both Ghanaian RVV responders and nonresponders (FDR, 0.008 vs 0.003) and Dutch infants and Ghanaian nonresponders (FDR, 0.002 vs 0.009). Conclusions. The intestinal microbiome composition correlates significantly with RVV immunogenicity and may contribute to the diminished RVV immunogenicity observed in developing countries.
  • Solastie, Anna; Leino, Tuija; Ollgren, Jukka (2020)
    Introduction: Even with vaccines available since 2006, rotavirus continues to be a major cause of acute gastroenteritis globally in children under 5 years old. Finland introduced the rotavirus vaccine to its national vaccination programme in 2009. Since then hospitalizations due to gastroenteritis caused by rotavirus (RVGE) and of all causes (AGE) have been reduced significantly in young children. Methods: We performed a retrospective analysis of data from register databases consisting of over 200 000 children aged 0.5-2 years. Children born before rotavirus vaccines were available (2002, 2003) and after the implementation of rotavirus vaccination programme (2014, 2015) were followed for episodes of acute infectious gastroenteritis. We calculated the incidences of hospital outpatient and inpatient episodes and used individual vaccination records to estimate the overall, total, direct and indirect vaccine effect (VE %). Results: Among children born in 2014 and 2015, there was a 96% reduction in inpatient RVGE episodes and a 78% reduction in episodes of inpatient AGE compared to the pre-vaccination era, comprising the overall VE. Direct effectiveness was 96% and 53% for RVGE and AGE respectively. Herd effect i.e. indirect protection was estimated to be 67% against inpatient RVGE and 56% against inpatient AGE. Protection acquired by the vaccinated children when compared to pre vaccination era i.e. the total VE was 99% for inpatient RVGE and 79% for inpatient AGE. Conclusions: Although overall incidences for every disease type studied were reduced, rotavirus is still circulating with seasonality and there is a slight shift of disease towards the older age groups. Together with changes observed in the distribution of rotavirus genotypes, our results indicate that continuous monitoring is still necessary. (C) 2020 The Authors. Published by Elsevier Ltd.