Ljungan virus is endemic in rodents in the UK.

Ljungan virus is a recently identified member of the family Picornaviridae that was isolated from bank voles in Sweden. LjV has been associated with [corrected] type 1 diabetes-like symptoms and myocarditis in bank voles (Myodes glareolus), and it has been suggested that it has zoonotic potential. Here, we show for the first time that Ljungan virus is prevalent (20-27 % positive by PCR) in four species of UK rodent (Myodes glareolus [bank vole], Apodemus sylvaticus [wood mouse], Microtus agrestis [field vole] and Mus musculus [house mouse]). Sequence analysis showed that Ljungan virus of genotypes 1 and 2 were present, although genotype 1 was more prevalent and more frequently associated with brain tissue. This study highlights the prevalence of Ljungan virus in the UK and the need for assessment [corrected] of its zoonotic potential.

Detection and molecular characterisation of noroviruses in hospitalised children in Malawi, 1997-2007.

Despite the increasing recognition of noroviruses as major pathogens associated with community-acquired diarrhoea in children, there are few studies from Africa. Long-term surveillance studies of rotavirus gastroenteritis in Malawian children have provided an opportunity to undertake a study of the importance and epidemiological features of norovirus infection in this population. Faecal specimens were collected from children <5 years of age admitted to hospital with acute diarrhoea, as well as from a comparison group of diarrhoea-free children, in Blantyre, Malawi between 1997 and 2007. Norovirus was detected using real-time PCR and strains genotyped by nucleotide sequence analysis. Norovirus was detected in 220/1,941 (11.3%) faecal specimens, comprising genogroup GI (1.8%), GII (9.4%) and mixed GI/GII (0.1%). The median age of children with norovirus was 6 months (range, 0-48 months). Norovirus was detected throughout the year, with peaks at the end of the rainy season (March) and towards the end of the dry season (August-November). Norovirus GII.4 was the most commonly detected genotype accounting for 70% of strains characterised, followed by GII.2 (6%), GII.6 (4%) and GII.12 (4%). Sub typing of GII.4 noroviruses demonstrated local circulation of strains prior to their subsequent detection in association with global epidemics of gastroenteritis. The prevalence of norovirus in children without diarrhoea was similar to the level in cases. This largest study to date of norovirus infection in African children indicates the potential role of paediatric surveillance in predicting the emergence of norovirus strains with global epidemic potential.

Campylobacter infection in children in Malawi is common and is frequently associated with enteric virus co-infections.

BACKGROUND: Campylobacter species are the most common cause of bacterial gastroenteritis in the developed world. However, comparatively few studies have determined the epidemiological features of campylobacteriosis in resource-poor settings. METHODS: A total of 1,941 faecal specimens collected from symptomatic (diarrhoeic) children and 507 specimens from asymptomatic (non-diarrhoeic) children hospitalised in Blantyre, Malawi, between 1997 and 2007, and previously tested for the presence of rotavirus and norovirus, was analysed for C. jejuni and C. coli using a real time PCR assay. RESULTS: Campylobacter species were detected in 415/1,941 (21%) of diarrhoeic children, with C. jejuni accounting for 85% of all cases. The median age of children with Campylobacter infection was 11 months (range 0.1-55 months), and was significantly higher than that for children with rotavirus and norovirus (6 months and 7 months respectively; P<0.001). Co-infection with either rotavirus or norovirus was noted in 41% of all cases in the diarrhoeic group. In contrast, the detection rate of Campylobacter in the non-diarrhoeic group was 14%, with viral co-infection identified in 16% of children with Campylobacter. There was no association between Campylobacter detection rate and season over the 10 year period. DISCUSSION: Using molecular detection methodology in hospitalised Malawian children, we have demonstrated a high prevalence of Campylobacter infection, with frequent viral co-infection. The burden of Campylobacter infection in young African children may be greater than previously recognised.

Surveillance of rotavirus gastro-enteritis in children in Blantyre, Malawi.

BACKGROUND: Rotavirus is a leading cause of acute gastro-enteritis in infants and young children worldwide. Previous studies of rotavirus gastro-enteritis in Malawi have documented a high disease burden with an extensive diversity of circulating rotavirus strains. METHODS: In anticipation of the introduction of national rotavirus vaccination, a 2-year surveillance study was undertaken in 2008 and 2009 of children in Blantyre seeking hospital care for acute gastro-enteritis. Rotavirus was detected in faecal specimens by ELISA. Rotavirus G and P types were determined by RT-PCR. RESULTS: Rotavirus, which circulated throughout the year, was detected in 220/720 (31%) children. Over 85% of patients with rotavirus gastro-enteritis were <1 year of age. A total of 13 rotavirus G/P types were identified, the most common strains being G1P[8] (39·5%), G12P[6] (23·2%), G2P[4] (9·5%), G9P[8] (6·8%) and G8P[4] (6·4%). CONCLUSIONS: The data confirm the importance of rotavirus infection in young Malawian children and highlight the continuing diversity of circulating rotavirus strains in Blantyre. Together with previous observations, the findings contribute to a baseline of data against which the impact of future rotavirus vaccination in Malawi can be assessed.

G8 rotaviruses with conserved genotype constellations detected in Malawi over 10 years (1997-2007) display frequent gene reassortment among strains co-circulating in humans.

Rotavirus A, the most common cause of severe diarrhoea in children worldwide, occurs in five major VP7 (G) and VP4 (P) genotype combinations, comprising G1P[8], G2P[4], G3P[8], G4P[8] and G9P[8]. However, G8, a common bovine rotavirus genotype, has been reported frequently among children in African countries. Surveillance of rotavirus gastroenteritis conducted in a sentinel hospital in Blantyre, Malawi between 1997 and 2007 provided a rare opportunity to examine the whole genotype constellation of G8 strains and their evolution over time. A sample of 27 (9.0 %) of 299 G8 strains was selected to represent each surveillance year and a range of P genotypes, which shifted in predominance from P[6] to P[4] and P[8] during the study period. Following cell culture adaptation, whole genome sequencing demonstrated that the genetic background of 26 strains possessed the DS-1 genotype constellation. A single G8P[6] strain was a reassortant in which both NSP2 and NSP5 genes from strains with the Wa genotype constellation had been inserted into a strain with the DS-1 genotype background. Phylogenetic analysis suggested frequent reassortment among co-circulating strains with the DS-1 genotype constellation. Little evidence was identified to suggest the introduction of contemporary bovine rotavirus genes into any of the 27 G8 strains examined. In conclusion, Malawian G8 strains are closely related to other human strains with the DS-1 genotype constellation. They have evolved over the last decade through genetic reassortment with other human rotaviruses, changing their VP4 genotypes while maintaining a conserved genotype constellation for the remaining structural and non-structural proteins.

PCR based bronchoscopic detection of common respiratory pathogens in chronic cough: a case control study.

BACKGROUND: Viral respiratory tract infection is the most frequent cause of acute cough and is reported at onset in about one third of patients with chronic cough. Persistent infection is therefore one possible explanation for the cough reflex hypersensitivity and pulmonary inflammation reported in chronic cough patients. METHODS: Bronchoscopic endobronchial biopsies and bronchoalveolar lavage cell counts were obtained from ten healthy volunteers and twenty treatment resistant chronic cough patients (10 selected for lavage lymphocytosis). A screen for known respiratory pathogens was performed on biopsy tissue. Chronic cough patients also underwent cough reflex sensitivity testing using citric acid. RESULTS: There was no significant difference in incidence of infection between healthy volunteers and chronic cough patients (p = 0.115) or non-lymphocytic and lymphocytic groups (p = 0.404). BAL cell percentages were not significantly different between healthy volunteers and chronic cough patients without lymphocytosis. Lymphocytic patients however had a significantly raised percentage of lymphocytes (p < 0.01), neutrophils (p < 0.05), eosinophils (p < 0.05) and decreased macrophages (p < 0.001) verses healthy volunteers. There was no significant difference in the cough reflex sensitivity between non-lymphocytic and lymphocytic patients (p = 0.536). CONCLUSIONS: This study indicates latent infection in the lung is unlikely to play an important role in chronic cough, but a role for undetected or undetectable pathogens in either the lung or a distal site could not be ruled out. TRIALS REGISTRATION: Current Controlled Trials ISRCTN62337037 & ISRCTN40147207.

Molecular characterization of rotavirus strains detected during a clinical trial of a human rotavirus vaccine in Blantyre, Malawi.

The human, G1P[8] rotavirus vaccine (Rotarix™) significantly reduced severe rotavirus gastroenteritis episodes in a clinical trial in South Africa and Malawi, but vaccine efficacy was lower in Malawi (49.5%) than reported in South Africa (76.9%) and elsewhere. The aim of this study was to examine the molecular relationships of circulating wild-type rotaviruses detected during the clinical trial in Malawi to RIX4414 (the strain contained in Rotarix™) and to common human rotavirus strains. Of 88 rotavirus-positive, diarrhoeal stool specimens, 43 rotaviruses exhibited identifiable RNA migration patterns when examined by polyacrylamide gel electrophoresis. The genes encoding VP7, VP4, VP6 and NSP4 of 5 representative strains possessing genotypes G12P[6], G1P[8], G9P[8], and G8P[4] were sequenced. While their VP7 (G) and VP4 (P) genotype designations were confirmed, the VP6 (I) and NSP4 (E) genotypes were either I1E1 or I2E2, indicating that they were of human rotavirus origin. RNA-RNA hybridization using 21 culture-adapted strains showed that Malawian rotaviruses had a genomic RNA constellation common to either the Wa-like or the DS-1 like human rotaviruses. Overall, the Malawi strains appear similar in their genetic make-up to rotaviruses described in countries where vaccine efficacy is greater, suggesting that the lower efficacy in Malawi is unlikely to be explained by the diversity of circulating strains.

Unusual norovirus and rotavirus genotypes in Ethiopia.

BACKGROUND: Gastro-enteritis is associated with significant mortality in low- and middle-income countries, and rotavirus and norovirus are the principal viral agents implicated. AIMS: To investigate the molecular epidemiology and burden of disease associated with rotavirus and norovirus in children attending a health centre in Ethiopia. METHODS: A cross-sectional study was conducted in children attending a health centre in Awassa, southern Ethiopia. Children with diarrhoea (cases) and without diarrhoea (controls) were recruited over a 6-month period from December 2008 to May 2009. Rotavirus was detected by ELISA and genotyped by RT-PCR, and norovirus was amplified by RT-PCR with genotyping by sequence analysis of RT-PCR products. RESULTS: Rotavirus was detected in 44/200 (22%) cases and in none of the controls, with genotypes G3P[6] (48%), G1P[8] (27%) and G2P[4] (7%) being the strains most commonly identified. Norovirus was detected in 16 (8%) of 200 cases and in 4 (7%) of 57 controls. Norovirus GII.3 was the strain most commonly detected (40%: 8/20) and ten other genotypes were also detected. CONCLUSION: Rotavirus is a common cause of severe gastro-enteritis in children in Ethiopia; however, norovirus occurred with a similar frequency in cases and controls. A globally uncommon strain type, G3P[6], predominated within the rotavirus strains detected.

Clinical features and molecular epidemiology of rotavirus and norovirus infections in Libyan children.

Rotaviruses and noroviruses are leading viral causes of diarrhoea in children. A cross-sectional study was undertaken among children aged <5 years with acute gastroenteritis at Al-Jala Children's Hospital, Tripoli, Libya, from October 2007 to September 2008. Of 1,090 fecal samples collected, 260 from inpatients and 830 from outpatients, all inpatients and approximately a third of outpatients, selected systematically, were investigated for rotavirus and norovirus infection by ELISA and real-time RT-PCR, respectively. Of 520 fecal samples examined (inpatients = 260, outpatients = 260), 164 (31.5%) had rotavirus and 91 (17.5%) had norovirus detected. Rotavirus was identified more often among inpatients than outpatients (35.8% vs. 27.3% respectively, P = 0.038). Norovirus was detected more commonly among outpatients than inpatients (21.2% vs. 13.8% respectively, P = 0.028). The peak incidence of infection with both viruses was among children aged between 6 and 11 months. The number of rotavirus cases was highest between November and June with a peak detection rate of 50% in January. Norovirus occurred most commonly from May through August with a peak detection rate of 47% in August. The most prevalent rotavirus genotypes were P[8], G9 (n = 116, 65.9%), followed by P[8],G1 (n = 49, 27.8%); a single P[9], G3 strain was detected. There were seven distinct electropherotypes among the G9 strains and all belonged to VP7 Lineage III. Among 91 noroviruses identified, 90 were genogroup II. Of 26 genogroup II noroviruses examined, all were genotype GII.4. Rotaviruses and noroviruses are both important causes of gastrointestinal infection among young children in Libya.

PCR improves diagnostic yield from lung aspiration in Malawian children with radiologically confirmed pneumonia.

BACKGROUND: Accurate data on childhood pneumonia aetiology are essential especially from regions where mortality is high, in order to inform case-management guidelines and the potential of prevention strategies such as bacterial conjugate vaccines. Yield from blood culture is low, but lung aspirate culture provides a higher diagnostic yield. We aimed to determine if diagnostic yield could be increased further by polymerase chain reaction (PCR) detection of bacteria (Streptococcus pneumoniae and Haemophilus influenzae b) and viruses in lung aspirate fluid. METHODS: A total of 95 children with radiological focal, lobar or segmental consolidation had lung aspirate performed and sent for bacterial culture and for PCR for detection of bacteria, viruses and Pneumocystis jirovecii. In children with a pneumococcal aetiology, pneumococcal bacterial loads were calculated in blood and lung aspirate fluid. RESULTS: Blood culture identified a bacterial pathogen in only 8 patients (8%). With the addition of PCR on lung aspirate samples, causative pathogens (bacterial, viral, pneumocystis) were identified singly or as co-infections in 59 children (62%). The commonest bacterial organism was S.pneumoniae (41%), followed by H. influenzae b (6%), and the commonest virus identified was adenovirus (16%), followed by human bocavirus (HBoV) (4%), either as single or co-infection. CONCLUSIONS: In a select group of African children, lung aspirate PCR significantly improves diagnostic yield. Our study confirms a major role of S.pneumoniae and viruses in the aetiology of childhood pneumonia in Africa.

Acute diarrhoea in a community cohort of children who received an oral rotavirus vaccine in Northeast Brazil.

Rotavirus is an important cause of childhood diarrhoea. A monovalent rotavirus vaccine (Rotarix®) was introduced into the Immunization Program of Brazil in 2006. In this study, we describe the incidence and burden of disease of rotavirus diarrhoea in two cohorts of children (vaccinated and unvaccinated). We followed two groups of 250 children under one year old, who were enrolled in December 2006 from a low-income residential area in Northeast Brazil. The children were monitored every two weeks for two years. Stool samples from children with diarrhoea were examined for the presence of rotavirus. Rotaviruses were genotyped using real time-polymerase chain reaction. The mean numbers of all-cause diarrhoea episodes/child (adjusted for age) in the first year were 0.87 and 0.84, in vaccinated and unvaccinated children, respectively. During the second year, the number of episodes/child decreased to 0.52 and 0.42. Only 16 (4.9%) of 330 stool samples were rotavirus-positive (10 vaccinated and 6 unvaccinated children) and only P[4]G2 rotaviruses were identified. All-cause diarrhoea episodes were more severe in unvaccinated children in the first year of age (p < 0.05), while vaccinated children had more severe episodes 18 months after vaccination. Rotavirus diarrhoea incidence was very low in both groups.

Acute diarrhoea in a community cohort of children who received an oral rotavirus vaccine in Northeast Brazil

Rotavirus is an important cause of childhood diarrhoea. A monovalent rotavirus vaccine (Rotarix®) was introduced into the Immunization Program of Brazil in 2006. In this study, we describe the incidence and burden of disease of rotavirus diarrhoea in two cohorts of children (vaccinated and unvaccinated). We followed two groups of 250 children under one year old, who were enrolled in December 2006 from a low-income residential area in Northeast Brazil. The children were monitored every two weeks for two years. Stool samples from children with diarrhoea were examined for the presence of rotavirus. Rotaviruses were genotyped using real time-polymerase chain reaction. The mean numbers of all-cause diarrhoea episodes/child (adjusted for age) in the first year were 0.87 and 0.84, in vaccinated and unvaccinated children, respectively. During the second year, the number of episodes/child decreased to 0.52 and 0.42. Only 16 (4.9 percent) of 330 stool samples were rotavirus-positive (10 vaccinated and 6 unvaccinated children) and only P[4]G2 rotaviruses were identified. All-cause diarrhoea episodes were more severe in unvaccinated children in the first year of age (p < 0.05), while vaccinated children had more severe episodes 18 months after vaccination. Rotavirus diarrhoea incidence was very low in both groups.

Detection and molecular characterisation of rotavirus and norovirus infections in Jordanian children with acute gastroenteritis.

Rotavirus and norovirus are globally important causes of paediatric gastroenteritis, but no studies of viral genotypes have been reported from Jordan. We undertook a molecular epidemiological study in children hospitalised with acute gastroenteritis in Jordan between January 2006 and December 2007. Among 368 children, rotavirus and norovirus infections were detected in 49.5% and 11.4% of children, respectively. Rotavirus genotypes P[8],G1 (56%), P[4],G2 (14%) and P[8],G9 (13%) were most commonly identified, consistent with results of global rotavirus surveillance studies. Norovirus GII.3 was the most commonly detected genotype, followed by GII.4, contrasting with most studies in which GII.4 has predominated.

Rotavirus and norovirus infections in children in Sana'a, Yemen.

OBJECTIVES: To describe the epidemiology of rotavirus and norovirus infection among children with acute gastroenteritis in Sana'a, Yemen. METHODS: A cross-sectional study from November 2007 to March 2009 of children aged 1 month to 5 years attending the emergency and outpatient departments of two hospitals in Sana'a with acute gastroenteritis. Rotavirus was detected by ELISA and genotyped by RT-PCR. Norovirus was detected by End Point RT-PCR and nucleotide sequencing. RESULTS: A total of 290 children (48% in the emergency department and 52% in the outpatient department of the children respectively) were enrolled. Rotavirus infections were detected in 78 (27%) and norovirus infections in 30 (10%). Rotavirus genotypes included G1P[8] (55%), G9P[8] (21%) and G2P[4] (12%) with G12 comprising 3% of strain types. The main norovirus genotype was GII.4 (27%) with >10 other genotypes detected. CONCLUSIONS: Rotavirus and norovirus infections are common causes of gastroenteritis in Yemen. Rotavirus vaccines could play a significant role in the control of acute childhood diarrhoea in this setting.

Molecular phylogenetic and evolutionary analyses of Muar strain of Japanese encephalitis virus reveal it is the missing fifth genotype.

Japanese encephalitis virus (JEV) is the most important cause of epidemic encephalitis worldwide but its origin is unknown. Epidemics of encephalitis suggestive of Japanese encephalitis (JE) were described in Japan from the 1870s onwards. Four genotypes of JEV have been characterised and representatives of each genotype have been fully sequenced. Based on limited information, a single isolate from Malaysia is thought to represent a putative fifth genotype. We have determined the complete nucleotide and amino acid sequence of Muar strain and compared it with other fully sequenced JEV genomes. Muar was the least similar, with nucleotide divergence ranging from 20.2 to 21.2% and amino acid divergence ranging from 8.5 to 9.9%. Phylogenetic analysis of Muar strain revealed that it does represent a distinct fifth genotype of JEV. We elucidated Muar signature amino acids in the envelope (E) protein, including E327 Glu on the exposed lateral surface of the putative receptor binding domain which distinguishes Muar strain from the other four genotypes. Evolutionary analysis of full-length JEV genomes revealed that the mean evolutionary rate is 4.35 × 10(-4) (3.4906 × 10(-4) to 5.303 × 10(-4)) nucleotides substitutions per site per year and suggests JEV originated from its ancestral virus in the mid 1500s in the Indonesia-Malaysia region and evolved there into different genotypes, which then spread across Asia. No strong evidence for positive selection was found between JEV strains of the five genotypes and the E gene has generally been subjected to strong purifying selection.

An evaluation of the RIDASCREEN and IDEIA enzyme immunoassays and the RIDAQUICK immunochromatographic test for the detection of norovirus in faecal specimens.

BACKGROUND: The detection of norovirus by ELISA and immunochromatographic methods may facilitate epidemiological studies into the global disease burden associated with norovirus gastroenteritis and provide a quick method of testing for norovirus infection. OBJECTIVES: To evaluate the new RIDASCREEN norovirus ELISA (3rd generation) and RIDAQUICK norovirus immunochromatographic test on a collection of samples from Brazilian children with acute gastroenteritis, and compare them against the established 2nd generation IDEIA norovirus assay. STUDY DESIGN: Reverse transcriptase PCR, the study reference standard, was used to test 726 specimens for the presence of norovirus. All 96 norovirus positive samples and a systematic selection of negative samples were tested by RIDASCREEN, RIDAQUICK and IDEIA norovirus tests. RESULTS: The sensitivity of RIDASCREEN for the detection of norovirus was 63% (95% CI: 53-72%) and RIDAQUICK 69% (95% CI: 58-78%); both were >98% specific. The IDEIA had a sensitivity of 45% (95% CI: 35-55%), significantly lower than RIDASCREEN and RIDAQUICK (p≤0.01). The sensitivity of RIDASCREEN and RIDAQUICK in detecting GII.4 noroviruses, the principal norovirus strain identified in community and nosocomial infection globally, was 78% and 88% respectively. CONCLUSION: The norovirus RIDASCREEN test may be useful in epidemiological studies of norovirus infection and the norovirus RIDAQUICK test offers an accurate and rapid method of detecting norovirus infection.

Epidemiology of rotavirus infection in children in Blantyre, Malawi, 1997-2007.

Acute gastroenteritis caused by rotavirus infection is an important cause of morbidity and mortality among infants and young children in Africa. From 1997 through 2007, we enrolled 3740 children <5 years of age with acute gastroenteritis who received hospital care at the Queen Elizabeth Central Hospital in Blantyre, Malawi. Group A rotavirus was detected in fecal specimens by enzyme immunoassay. Rotavirus strains were characterized for VP7 (G) and VP4 (P) types with use of reverse-transcription polymerase chain reaction. Overall, rotavirus was detected in one-third of children. The median age of children with rotavirus gastroenteritis was 7.8 months, compared with 10.9 months for those without rotavirus in stool specimens (P > .001). Rotavirus circulated throughout the year, with the detection proportion greatest during the dry season (from May through October). A total of 15 single rotavirus strain types were detected during the study period, with genotypes P[8]G1, P[6]G8, P[4]G8, P[6]G1, P[8]G3, and P[6]G9 comprising 83% of all strains characterized. Serotype G12 was detected for the first time in Blantyre during the final 2 years of study. Zoonotic transmission and viral reassortment contributed to the rich diversity of strains identified. Current rotavirus vaccines have the potential to greatly reduce the rotavirus disease burden in Malawi, but they will be required to protect against a broad range of rotavirus serotypes in a young population with year-round rotavirus exposure.

Detection of norovirus in mouthwash samples from patients with acute gastroenteritis.

BACKGROUND: Norovirus infection is characteristically associated with vomiting which is known to contain a high concentration of viral particles. The oral cavity is therefore likely to become contaminated with norovirus during episodes of gastroenteritis. OBJECTIVE: To investigate the oral detection of norovirus in patients with norovirus gastroenteritis. STUDY DESIGN: Faecal and oral mouthwash samples were collected in two separate settings. In the first setting, samples were collected repeatedly over a 3-week period from six family members experiencing a domestic outbreak of norovirus gastroenteritis. Secondly, samples were collected at a single time point following disease onset from 59 patients hospitalised with norovirus gastroenteritis. Norovirus detection in oral and faecal samples was undertaken by RT-PCR. RESULTS: In the family study, norovirus was detected in early morning mouthwash samples for 10-15 days following disease onset from each of six family members. In the hospital study, 14/59 hospitalised adults with norovirus infection had norovirus detected in mouthwashes (24%; 14-37% 95% C.I.). For the hospitalised adults, the detection of norovirus in mouthwash samples was associated with the presence of vomiting (p=0.1); and in those patients with norovirus infection whose mouthwash samples were collected within 24h of the onset of vomiting, 59% (10/17) had norovirus detected. CONCLUSIONS: Oral mouthwashes may provide an adjunct to faecal sampling to support the diagnosis of norovirus infection. The detection of norovirus in orally-derived material raises the possibility of oral-to-oral norovirus transmission, and that this potential for transmission may extend beyond the immediate symptomatic period.

Molecular epidemiology of rotavirus diarrhea among children aged <5 years in nepal: predominance of emergent G12 strains during 2 years.

A 2-year surveillance was performed in Kathmandu, Nepal, by collection of stool specimens from 1139 children aged <5 years who were hospitalized for acute diarrhea from November 2005 through October 2007. Of the 1139 samples, 379 (33%) had rotavirus strains identified by enzyme-linked immunosorbent assay; the most prevalent G type was G12, accounting for 50% of typed strains in 2005-2006 and 29% in 2006-2007, followed by G1 (26%) in 2005-2006 and by G9 (28%) and G2 (20%) in 2006-2007. The most prevalent P type was P[8], accounting for 47% of strains in 2005-2006 and 35% in 2006-2007, followed by P[6] (37% in 2005-2006 and 33% in 2006-2007) and P[4] (10% in 2005-2006 and 24% in 2006-2007). Of combined genotypes, G12P[6] was the most prevalent, accounting for 34% of strains in 2005-2006 and 24% in 2006-2007, followed by G1P[8] (23%) in 2005-2006 and G2P[4] (20%) in 2006-2007. An unusually high detection of G12 strains underscores the importance of continued surveillance of rotavirus strains.

Adenovirus infections within a family cohort in Iran.

BACKGROUND: Adenovirus is one of the most frequent viruses associated with acute respiratory infections (ARI). There is limited information of its transmission within the community. METHODS: Cohorts of 50 families with > or =two children were visited weekly for 2 months to ascertain the presence ARI in Rasht, Iran. Nasopharyngeal swabs were obtained from symptomatic participants and at 3-4-day intervals to assess the duration of adenovirus shedding. Adenoviruses were identified by PCR and adenovirus positive amplicons were subjected to DNA sequencing. RESULTS: Thirty-three (35%) of 94 ARI episodes in children and 8 (27%) of 30 episodes in adults were due to adenovirus (not significant, NS). 25/50 (50%) families had adenovirus infections. Children had more infections than adults, were more likely to develop symptoms if there was a symptomatic case within the household and episodes had a longer duration (P < 0.05). Adenoviruses were recovered for a median of 11 (interquartile range 5-26) days of follow up in children and 7 (2-20) days in adults (NS). Adenovirus-7 was the most frequent serotype (12 families), followed by adenovirus-6 (5 families), adenovirus-1 and 2 (4 families each), and adenovirus-5 (3 families). Both adenovirus-5 and 7 amplicons fell into two clusters. No mutations were observed during transmission within a family. CONCLUSION: A substantial proportion of ARI in the community are due to adenovirus with further transmission within the family. Children > or =2 years experienced a higher proportion of infections than younger children and adults. Viral shedding was more prolonged in children and adenovirus-7 and 5 predominated with several clusters co-circulating in the same season.