Viral Etiology of Acute Gastroenteritis Among Forcibly Displaced Myanmar Nationals and Adjacent Host Population in Bangladesh.

BACKGROUND: Since August 2017, Myanmar nationals from Rakhine state have crossed the border into Bangladesh and settled in Cox's Bazar, the World's largest refugee camp. Due to overcrowding, poor sanitation, and hygienic practices they have been under significant health risks including diarrheal diseases. The objective of this study is to determine the viral etiology of acute gastroenteritis (AGE) among forcibly displaced Myanmar nationals (FDMN) and adjacent Bangladeshi local host population (AHP). METHODS: From April 2018 to April 2019, we collected stool specimens from 764 FDMN and 1159 AHP of all ages. We tested 100 randomly selected specimens from each group for the most common AGE viruses. RESULTS: Among 200 diarrhea patients, 55% and 64% of FDMN and AHP patients, respectively, had viral infections; the most common viruses were rotavirus (29% vs 44%), adenovirus (24% vs 31%), and norovirus (14% vs 10%). In both populations, viral infections were significantly higher in children less than 5 years of age, compared with bacterial infections that were higher in patients older than 5 years of age (P ≤ .05). CONCLUSIONS: Disparities in viral and bacterial prevalence among various age groups warrant careful antibiotic usage, especially in children less than 5 years of age.

Sustained Decline in Acute Gastroenteritis-Associated Hospitalizations and Outpatient Visits Among American Indian/Alaska Native Children After Rotavirus Vaccine Introduction, 2001-2014.

We examined the uptake of rotavirus vaccine and compared trends in acute gastroenteritis (AGE)-associated hospitalizations and outpatient visits among American Indian and Alaska Native (AI/AN) children aged <5 years before and after introduction of the rotavirus vaccine. The rates of AGE-associated hospitalization and outpatient visits among AI/AN children remained below prevaccine levels.

Impact of maternal antibodies and infant gut microbiota on the immunogenicity of rotavirus vaccines in African, Indian and European infants: protocol for a prospective cohort study.

INTRODUCTION: Gastroenteritis is the leading cause of morbidity and mortality among young children living in resource-poor settings, majority of which is attributed to rotavirus. Rotavirus vaccination can therefore have a significant impact on infant mortality. However, rotavirus vaccine efficacy in Sub-Saharan Africa and Southeast Asia is significantly lower than in high-income countries. Maternally derived antibodies, infant gut microbiota and concomitant oral polio vaccination have been proposed as potential reasons for poor vaccine performance in low-income settings. The overall aim of this study is to compare the role of maternally derived antibodies and infant gut microbiota in determining immune response to rotavirus vaccine in high-income and low-income settings, using the same vaccine and a similar study protocol. METHODS AND ANALYSIS: The study is an observational cohort in three countries-Malawi, India and UK. Mothers will be enrolled in third trimester of pregnancy and followed up, along with infants after delivery, until the infant completes two doses of oral rotavirus vaccine (along with routine immunisation). The levels of prevaccination maternally derived rotavirus-specific antibodies (IgG) will be correlated with infant seroconversion and antibody titres, 4 weeks after the second dose of rotavirus vaccine. Both within-country and between-country comparisons of gut microbiome will be carried out between children who seroconvert and those who do not. The impact of oral polio vaccine coadministration on rotavirus vaccine response will be studied in Indian infants. ETHICS AND DISSEMINATION: Ethical approvals have been obtained from Integrated Research Application System (IRAS, NHS ethics) in UK, College of Medicine Research and Ethics Committee (COMREC) in Malawi and Institutional Review Board (IRB), Christian Medical College, Vellore in India. Participant recruitment and follow-up is ongoing at all three sites. Analysis of data, followed by publication of the results, is expected in 2018.

Norovirus and Sapovirus Epidemiology and Strain Characteristics among Navajo and Apache Infants.

Norovirus and sapovirus are important causes of acute gastroenteritis (AGE) among American Indian infants. We investigated the prevalence and molecular epidemiology of norovirus and sapovirus in American Indian infants who have historically experienced a high burden of AGE compared to other US populations. Stool samples were collected from 241 children with AGE (cases) and from 343 infants without AGE (controls) ≤9 months of age from 2002-2004. Cases experienced forceful vomiting and/or 3 or more watery or looser-than-normal stools in 24 hours. Stools were tested by real-time RT-PCR for norovirus GI, GII and GIV and sapovirus GI, GII, GIV and GV. Positive samples were genotyped after sequencing conventional RT-PCR products. Norovirus was identified in 76 (31.5%) of the cases and 70 (20.4%) of the controls (p<0.001). GII.3 and GII.4 Farmington Hills were the most frequently identified genotypes in 14.5% and 30.3% of cases and 17.1% and 27.1% of controls, respectively. Sapovirus GI and GII genotypes were identified in 8 (3.3%) of cases and 8 (2.3%) of controls and a single GIV virus was detected in a control. The same norovirus and sapovirus genotypes were circulating in the general U.S. population in the same time period. The high detection rate of norovirus in healthy controls suggests significant asymptomatic transmission in young infants in these communities.

Real-World Effectiveness of Pentavalent Rotavirus Vaccine Among Bedouin and Jewish Children in Southern Israel.

BACKGROUND: Pentavalent rotavirus vaccine (RV5) was introduced into the Israeli National Immunization Program in January 2011. We determined RV5 vaccine effectiveness (VE) in southern Israel, a region characterized by 2 distinct populations: Bedouins living in a low- to middle-income, semirural setting, and Jews living in a high-income, urban setting. METHODS: We enrolled vaccine-eligible children who visited the emergency department (ED) or were hospitalized due to acute gastroenteritis (AGE) during the first 3 rotavirus seasons after RV5 vaccine introduction (2011-2013). Fecal specimens were tested for rotavirus by enzyme immunoassay and genotyped. Vaccination among laboratory-confirmed rotavirus cases was compared with rotavirus-negative AGE controls. Regression models were used to calculate VE estimates by age, clinical setting, and ethnicity. RESULTS: Of 515 enrolled patients, 359 (70%) were Bedouin. Overall, 185 (36%) patients were rotavirus positive; 79 of 119 (66%) were G1P[8] genotype. The adjusted VE for a full 3-dose course of RV5 against ED visit or hospitalization was 63% (95% confidence interval [CI], 38%-78%). RV5 provided G1P[8] genotype-specific effectiveness of 78% (95% CI, 58%-88%). By age, RV5 VE was 64% (95% CI, 21%-84%) and 71% (95% CI, 39%-86%) among children aged 6-11 months and 12-23 months, respectively. By clinical setting, RV5 VE was 59% (95% CI, 23%-78%) against hospitalization, and 67% (95% CI, 11%-88%) against ED visit. The adjusted VE of a full RV5 course among Bedouin children was 62% (95% CI, 29%-79%). CONCLUSIONS: RV5 significantly protected against rotavirus-associated ED visits and hospitalizations in a diverse population of vaccine-eligible children living in southern Israel.

Diapers in war zones: ethnomedical factors in acute childhood gastroenteritis in Peshawar, Pakistan.

This article considers ethnomedical knowledge and practices among parents related to contraction of acute gastroenteritis among children in Peshawar, Pakistan. Research methods included analysis of the Emergency Pediatric Services' admission register, a structured interview administered to 47 parents of patients seen in the Khyber Medical College Teaching Hospital, semi-structured interviews of 12 staff, and four home visits among families with children treated at the hospital. The use of native research assistants and participant observation contributed to the reliability of the findings, though the ethnographic, home-visit sample is small. Our research indicated that infection rates are exacerbated in homes through two culturally salient practices and one socioeconomic condition. Various misconceptions propagate the recurrence or perserverance of acute gastroenteritis including assumptions about teething leading to poor knowledge of disease etiology, rehydration solutions leading to increased severity of disease, and diaper usage leading to the spread of disease. In our Discussion, we suggest how hospital structures of authority and gender hierarchy may impact hospital interactions, the flow of information, and its respective importance to the patient's parents leading to possible propagation of disease. These ethnographic data offer a relatively brief but targeted course of action to improve the effectiveness of prevention and treatment efforts.

A tradition and an epidemic: determinants of the campylobacteriosis winter peak in Switzerland.

Campylobacteriosis is the most frequently reported food borne infection in Switzerland. We investigated determinants of infections and illness experience in wintertime. A case-control study was conducted in Switzerland between December 2012 and February 2013. Cases were recruited among laboratory-confirmed campylobacteriosis patients. Population-based controls were matched according to age group, sex and canton of residence. We determined risk factors associated with campylobacteriosis, and help seeking behaviour and illness perception. The multivariable analysis identified two factors associated with an increased risk for campylobacteriosis: consumption of meat fondue (matched odds ratio [mOR] 4.0, 95% confidence interval [CI] 2.3-7.1) and travelling abroad (mOR 2.7, 95% CI 1.1-6.4). Univariable analysis among meat fondue consumers revealed chicken as the type of meat with the highest risk of disease (mOR 3.8, 95% CI 1.1-13.5). Most frequently reported signs and symptoms among patients were diarrhoea (98%), abdominal pain (81%), fever (66%), nausea (44%) and vomiting (34%). The median perceived disease severity was 8 on a 1-to-10 rating scale. Patients reported a median duration of illness of 7 days and 14% were hospitalised. Meat fondues, mostly "Fondue chinoise", traditionally consumed during the festive season in Switzerland, are the major driver of the epidemic campylobacteriosis peak in wintertime. At these meals, individual handling and consumption of chicken meat may play an important role in disease transmission. Laboratory-confirmed patients are severely ill and hospitalisation rate is considerable. Public health measures such as decontamination of chicken meat and improved food handling behaviour at the individual level are urgently needed.

Diverging trends in gastroenteritis hospitalizations during 2 decades in western Australian Aboriginal and non-Aboriginal children.

BACKGROUND: Gastroenteritis is a major cause of pediatric morbidity. We describe temporal, spatial and seasonal trends in age-specific gastroenteritis hospitalizations among Aboriginal and non-Aboriginal Australian children during 2 decades, providing a baseline to evaluate the impact of a rotavirus vaccine program begun in 2007. METHODS: We conducted a population-based, data linkage study of Aboriginal and non-Aboriginal births in Western Australia, 1983 to 2006, and analyzed gastroenteritis-coded hospitalizations before age 15 years in the cohort of 596,465 births. Hospitalization rates in Aboriginal and non-Aboriginal children and between geographical regions were compared between 1983 to 1994 and 1995 to 2006. RESULTS: Gastroenteritis rates were highest in children 6-11 months of age (Aboriginal: 259.3/1000/annum; non-Aboriginal: 22.7/1000/annum). Rates declined in Aboriginal children between 1983 to 1994 and 1995 to 2006, particularly in those 12-17 months of age (309/1000 to 179/1000). Rates in non-Aboriginal children<5 years increased 10-40%. The disparity for gastroenteritis rates between Aboriginal and non-Aboriginal children<5 years declined from being 15.4 times higher to 7.6 times higher in those aged 12-17 months and from 8.4 to 4.4 in those aged 2-4 years. Rates were highest in rural and remote regions, and diverging temporal trends were seen in different geographical regions. Seasonality varied between Aboriginal and non-Aboriginal children and climatic zones. CONCLUSIONS: This is the largest study of gastroenteritis hospitalization trends in children. We found diverging trends of gastroenteritis hospitalization rates in Aboriginal and non-Aboriginal children. Although rates have declined in Aboriginal children, disparity between Aboriginal and non-Aboriginal children continues. Our findings highlight the need to consider age, ethnicity, seasonality and climate when evaluating rotavirus vaccine programs.

Molecular characterization of noroviruses and HBGA from infected Quilombola children in Espirito Santo State, Brazil.

Noroviruses (NoV) are the main etiological agents of gastroenteritis outbreaks worldwide and susceptibility to NoV infection has been related to the histo-blood group antigen (HBGA). This study aimed to determine the prevalence of NoV strains and to evaluate the HBGA phenotype and genotype of children from semi-isolated Quilombola communities, descendents of black slaves in Brazil. A total of 397 children up to eleven years old, with and without diarrhea, from Quilombola Communities in the Espirito Santo State, Brazil, were investigated for the presence of NoV from August 2007 to September 2009. Feces were collected from all the children, and blood from the NoV positive children. NoV was screened by reverse transcription-PCR with primers for the RNA-dependent RNA polymerase region; genogroup was determined by PCR with primers for the C and D regions and genotyped by sequencing. HBGA phenotype was performed by gel-spinning and FUT2 and FUT3 were analyzed by PCR or sequencing analysis. NoV were detected in 9.2% (12/131) of diarrheic and 1.5% (4/266) of non-diarrheic children (p<0.05, Fisher's exact test). GI and GII genogroups were present in 12.5% and 87.5% of the samples, respectively. The following genotypes were characterized: GII.4 (25%), GII.12 (25%), GII.6 (12.5%) and GI.1 (6.3%), GI.3 (12.5%) and GI.4 (6.3%). Children infected with NoV showed the A (n = 6), O (n = 6), and B (n = 2) HBGA phenotypes, and 13 of them were classified as secretors (Se) and one as a non secretor (se). Mutations of Se (40), (171,216,357,428,739,960) were found for the FUT2 gene and mutations of Le (59, 202, 314) for the FUT3 gene. The only se child was infected by NoV GI, whereas the Se children were indiscriminately infected by GI or GII. This study showed rates of NoV infection in symptomatic and asymptomatic Quilombola children consistent with other studies. However, children under 12 months were seven times more affected than those between 1 and 5 years old. GII.12 was as frequent as GII.4 and GI.1 and GI.4 were described for the first time in Brazil. Owing to the small number of cases studied, no clear pattern of susceptibility and/or HBGA resistance could be inferred.

Demographic and clinical characteristics of Campylobacter bacteremia in children with and without predisposing factors.

BACKGROUND: Campylobacter, a common cause of childhood gastroenteritis, rarely causes bacteremia, which is reported mainly in immune-compromised children. Our aim was to compare demographic and clinical characteristics of childhood campylobacter bacteremia (CB) between children with and without risk factors for CB. METHODS: A retrospective, population-based study, conducted between 1989 and 2010. Risk factors were defined as immunodeficiency, malignancy, extreme prematurity or chronic diseases with malnutrition. RESULTS: Seventy-six CB episodes (1 per child/month) were identified in 14 children with risk factors (30 episodes) and 46 children without risk factors (46 episodes). Children with risk factors were older (mean age 120.0±72.8 vs. 16.2±27.6 months) with higher proportion of males (90.0% vs. 60.9%), less gastrointestinal symptoms (43.3% vs. 69.9%) and higher hospitalization rates (96.7% vs. 69.6%) compared with children without risk factors. Campylobacter jejuni and Campylobacter coli (46/47 of identified species) were the most common species in both groups. Positive campylobacter stool cultures were found only in children without risk factors (0% vs. 38.5%). No mortality cases were observed. All isolates tested for antibiotic susceptibility were sensitive to macrolides and carbapenems. CONCLUSIONS: Childhood CB is rare in southern Israel. The disease manifests as a single gastroenteritis complication in a previously healthy young child or as recurrent episodes in an older, immune-compromised child, usually without gastrointestinal symptoms. This disparity may reflect pathogenesis differences, with disease in the immune-competent being dependent on pathogen virulence, whereas disease in the immune-compromised being host dependent. Disease outcome is usually favorable, and macrolides remain the antibiotic treatment of choice.

Norovirus diversity in diarrheic children from an African-descendant settlement in Belém, Northern Brazil.

Norovirus (NoV), sapovirus (SaV) and human astrovirus (HAstV) are viral pathogens that are associated with outbreaks and sporadic cases of gastroenteritis. However, little is known about the occurrence of these pathogens in relatively isolated communities, such as the remnants of African-descendant villages ("Quilombola"). The objective of this study was the frequency determination of these viruses in children under 10 years, with and without gastroenteritis, from a "Quilombola" Community, Northern Brazil. A total of 159 stool samples were obtained from April/2008 to July/2010 and tested by an enzyme immunoassay (EIA) and reverse transcription-polymerase chain reaction (RT-PCR) to detect NoV, SaV and HAstV, and further molecular characterization was performed. These viruses were detected only in the diarrheic group. NoV was the most frequent viral agent detected (19.7%-16/81), followed by SaV (2.5%-2/81) and HAstV (1.2%-1/81). Of the 16 NoV-positive samples, 14 were sequenced with primers targeting the B region of the polymerase (ORF1) and the D region of the capsid (ORF2). The results showed a broad genetic diversity of NoV, with 12 strains being classified as GII-4 (5-41.7%), GII-6 (3-25%), GII-7 (2-16.7%), GII-17 (1-8.3%) and GI-2 (1-8.3%), as based on the polymerase region; 12 samples were classified, based on the capsid region, as GII-4 (6-50%, being 3-2006b variant and 3-2010 variant), GII-6 (3-25%), GII-17 (2-16.7%) and GII-20 (1-8.3%). One NoV-strain showed dual genotype specificity, based on the polymerase and capsid region (GII-7/GII-20). This study provides, for the first time, epidemiological and molecular information on the circulation of NoV, SaV and HAstV in African-descendant communities in Northern Brazil and identifies NoV genotypes that were different from those detected previously in studies conducted in the urban area of Belém. It remains to be determined why a broader NoV diversity was observed in such a semi-isolated community.

Changes in hospitalisations for acute gastroenteritis in Australia after the national rotavirus vaccination program.

OBJECTIVE: To evaluate the impact of the Australian rotavirus vaccination program on both rotavirus and all-cause acute gastroenteritis (AGE) hospitalisations and to compare outcomes in Indigenous and non-Indigenous people. DESIGN AND SETTING: Retrospective analysis of the Australian Institute of Health and Welfare National Hospital Morbidity database for hospitalisations coded as rotavirus and all-cause AGE, between 1 July 2001 and 30 June 2010. MAIN OUTCOME MEASURES: Age-specific hospitalisation rates in Indigenous and non-Indigenous people, before and after the introduction of the vaccine program in July 2007. RESULTS: There was a 71% decline in rotavirus-coded hospitalisations of children aged < 5 years between periods before and after rotavirus vaccination (from 261 per 100,000 to 75 per 100,000). There was also a 38% decline in non-rotavirus coded AGE hospitalisations (from 1419 per 100,000 to 880 per 100,000). This represented more than 7700 hospitalisations of children aged < 5 years being averted in the financial year 2009-10. Reductions were also observed in the 5-19-years age group, suggesting that transmission of virus was reduced at a population level. Decreases in hospitalisations of Indigenous children were smaller than those for the general population, and fluctuated by location and year. CONCLUSIONS: These data show a sustained and substantial decline in severe rotavirus disease and all-cause AGE since the introduction of rotavirus vaccination, most pronounced in the target age group, but with evidence of herd immunity. The impact of rotavirus vaccination in Indigenous children in hyperendemic settings was less remarkable.

Clinical characteristics of obstructive uropathy associated with rotavirus gastroenteritis in Japan.

AIMS: Rotavirus gastroenteritis is severe and often results in dehydration and pre-renal azotemia. However, we have encountered four children with acute obstructive uropathy associated with acute rotavirus gastroenteritis, and several similar cases have been reported. Therefore, the aim of the present study was to clarify the epidemiology and clinical features of acute obstructive uropathy associated with acute rotavirus gastroenteritis in Japanese children. PATIENTS AND METHODS: We sent questionnaires to all members of the Japanese Society for Nephrology and all authors who had published case reports of this disease in Japan, inquiring about patient age at diagnosis, sex, the type of stones, laboratory data and other factors. RESULTS: 21 reported patients were evaluable, ranging from 0.4 to 3 years. The sex distribution showed a strong male prevalence. Oliguria had appeared about 7 days after the onset of gastroenteritis. Most of the patients showed hyperuricemia and hyponatremia. The stones consisted mainly of ammonium acid urate. The patients were discharged with normal renal function. CONCLUSION: Although obstructive uropathy associated with rotavirus gastroenteritis is very rare, this disease condition should be explored when anuria is refractory to sufficient fluid replacement therapy or when oliguria persists despite recovery of the gastrointestinal symptoms.

Travel-associated salmonella and campylobacter gastroenteritis in England: estimation of under-ascertainment through national laboratory surveillance.

Increased international travel raises the importance of accurate surveillance of travel-associated gastroenteric pathogens to improve treatment and the investigation of cross-border outbreaks. This study found that 45% of Salmonella and 17% of Campylobacter infections in England were travel-associated, but only 29 and 3% of travel histories were accurately identified by national laboratory surveillance. More structured data collection forms and staff training may be needed to address this.

Fit for the fight? Illnesses in the Norwegian team in the Vancouver Olympic Games.

BACKGROUND: The development of strategies to prevent illnesses before and during Olympic Games provides a basis for improved health and Olympic results. OBJECTIVE: (1) To document the efficacy of a prevention programme on illness in a national Olympic team before and during the 2010 Vancouver Olympic Winter Games (OWG), (2) to compare the illness incidence in the Norwegian team with Norwegian incidence data during the Turin 2006 OWG and (3) to compare the illness incidence in the Norwegian team with illness rates of other nations in the Vancouver OWG. METHODS: Information on prevention measures of illnesses in the Norwegian Olympic team was based on interviews with the Chief Medical Officer (CMO) and the Chief Nutrition and Sport Psychology Officers, and on a review of CMO reports before and after the 2010 OWG. The prevalence data on illness were obtained from the daily reports on injuries and illness to the International Olympic Committee. RESULTS: The illness rate was 5.1% (five of 99 athletes) compared with 17.3% (13 out of 75 athletes) in Turin (p=0.008). A total of four athletes missed one competition during the Vancouver Games owing to illness, compared with eight in Turin. The average illness rate for all nations in the Vancouver OWG was 7.2%. Conclusions Although no definite cause-and-effect link between the implementation of preventive measures and the prevalence of illness in the 2010 OWG could be established, the reduced illness rate compared with the 2006 OWG, and the low prevalence of illnesses compared with other nations in the Vancouver OWG suggest that the preparations were effective.

Increased risk of hospitalization for acute lower respiratory tract infection among Australian indigenous infants 5-23 months of age following pneumococcal vaccination: a cohort study.

BACKGROUND: Australian Indigenous children are the only population worldwide to receive the 7-valent pneumococcal conjugate vaccine (7vPCV) at 2, 4, and 6 months of age and the 23-valent pneumococcal polysaccharide vaccine (23vPPV) at 18 months of age. We evaluated this program's effectiveness in reducing the risk of hospitalization for acute lower respiratory tract infection (ALRI) in Northern Territory (NT) Indigenous children aged 5-23 months. METHODS: We conducted a retrospective cohort study involving all NT Indigenous children born from 1 April 2000 through 31 October 2004. Person-time at-risk after 0, 1, 2, and 3 doses of 7vPCV and after 0 and 1 dose of 23vPPV and the number of ALRI following each dose were used to calculate dose-specific rates of ALRI for children 5-23 months of age. Rates were compared using Cox proportional hazards models, with the number of doses of each vaccine serving as time-dependent covariates. RESULTS: There were 5482 children and 8315 child-years at risk, with 2174 episodes of ALRI requiring hospitalization (overall incidence, 261 episodes per 1000 child-years at risk). Elevated risk of ALRI requiring hospitalization was observed after each dose of the 7vPCV vaccine, compared with that for children who received no doses, and an even greater elevation in risk was observed after each dose of the 23vPPV (adjusted hazard ratio [HR] vs no dose, 1.39; 95% confidence interval [CI], 1.12-1.71; P=.002). Risk was highest among children vaccinated with the 23vPPV who had received <3 doses of the 7vPCV (adjusted HR, 1.81; 95% CI, 1.32-2.48). CONCLUSIONS: Our results suggest an increased risk of ALRI requiring hospitalization after pneumococcal vaccination, particularly after receipt of the 23vPPV booster. The use of the 23vPPV booster should be reevaluated.

Rotavirus gastroenteritis in the Northern Territory, 1995-2004.

OBJECTIVE: To present data on rotavirus notifications in the Northern Territory to provide knowledge about the local epidemiology of rotavirus gastroenteritis that can be used to inform the use and funding of rotavirus vaccines. DESIGN: Retrospective analysis of data from the Northern Territory Notifiable Diseases Database. PARTICIPANTS AND SETTING: Patients with cases of rotavirus infection notified to the NT Centre for Disease Control from 1 January 1995 to 31 December 2004. MAIN OUTCOME MEASURES: Patterns of rotavirus notifications over time; infection rates in Indigenous versus non-Indigenous children aged 0-5 years; age groups infected with rotavirus. RESULTS: Numbers of rotavirus notifications over the period 1995-2004 show annual, monthly and regional variability. The rotavirus notification rate for Indigenous children aged 0-5 years was 2.75 per 100 per year, compared with 0.98 for non-Indigenous children, with a relative risk for Indigenous children of 2.17 (95% CI, 1.97-2.39) over the 10 years. Indigenous children infected with rotavirus were younger than non-Indigenous children, with median ages of 11 months and 16 months, respectively. Rotavirus gastroenteritis occurred in outbreaks, transmitted over months throughout the NT. CONCLUSION: Large numbers of cases of rotavirus gastroenteritis affecting Indigenous and non-Indigenous children in the NT are notified every year. The rate in Indigenous children may be decreasing relative to non-Indigenous children. An effective rotavirus vaccine could prevent significant morbidity.

Characterization of an astrovirus genotype 2 strain causing an extensive outbreak of gastroenteritis among Maxakali Indians, Southeast Brazil.

BACKGROUND: Human astroviruses (HAstVs) are a common cause of sporadic diarrhea in children but large outbreaks occur in children's day care centers, schools and in homes for the elderly. OBJECTIVES: To report a large outbreak of acute gastroenteritis that occurred in January 2004 among Indians from the Maxakali Reserve in the State of Minas Gerais, Brazil. STUDY DESIGN: Fecal samples from 46 Maxakali patients were collected and tested for a range of enteric pathogens. HAstVs was detected by EIA and strains were confirmed by RT-PCR and typed by direct sequencing. Clinical information was collected. RESULTS: The illness which affected more than 100 children under 6 years of age was characterized by watery diarrhea, fever and vomiting. HAstV-2 was the sole enteropathogen detected in 26 (56%) of 46 samples analyzed by EIA and/or RT-PCR. The 17 positive samples sequenced were identical in a 348bp region used for phylogenetic analysis and were classified as genotype 2. CONCLUSIONS: This is the first description of an outbreak of HAstV-2 gastroenteritis in a population of Brazilian Indians. The magnitude of the outbreak and the severity of the disease underscore the need to better understand the epidemiology of astrovirus and other enteric agents in these populations.