The public health significance of giardiasis and cryptosporidiosis in sheep is currently unclear. Some research suggests that they are probably not an important zoonotic reservoir, whilst other research indicates this potential exists, and some outbreaks have also been associated with infections in sheep. Actions to limit water supply contamination by sheep have sometimes been severe, occasionally creating problems between farming and public health communities. Here our knowledge on these parasites in both sheep and goats is reviewed; although direct evidence of transmission to humans via water supply contamination is limited, the data accrued indicate that this is a real possibility. As cryptosporidiosis in sheep is generally more prevalent than giardiasis, and species/genotypes of Cryptosporidium infections in sheep are likely to be infectious to humans, this parasite may be considered the greater threat. Nevertheless, geographical variation in prevalence and genotypic distribution is extensive and as measures to limit sheep grazing can have a highly negative impact, it is important that cases are judged individually. If water contamination from a particular population of sheep/goats is suspected, then suitable investigations should be instigated, investigating both prevalence and species/genotype, before precautionary measures are imposed.

The incidence and causes of infectious intestinal disease (IID) in children aged <5 years presenting to general practitioners (GPs) were estimated. During a 12-month period, soiled nappies were collected from children presenting with symptoms suggestive of IID in a network of 65 GPs located across England. Molecular methods were used to detect a range of enteric pathogens including viruses, bacteria and parasites. Genotyping was performed on rotavirus and norovirus isolates. A total of 583 nappies were collected from 554 children; a pathogen was detected in 361 (62%) specimens. In the 43 practices 1584 new episodes of IID were recorded in a population averaging 19774; the specimen capture rate was 28%. IID incidence peaked during March and April. Norovirus (24·5%), rotavirus (19·0%) and sapovirus (12·7%) were most commonly detected, and mixed infections were detected in 11·7% of cases. Strain characterization revealed G1P[8] (65·8%), G4P[4] (8·1%) and G9P[8] (8·1%) as the most common rotavirus genotypes, similar to the UK national distribution. GII-3 (42·9%) and GII-4 (39·7%) were the most common norovirus genotypes; this was significantly different (P<0·005) to the national distribution.

Of 303 children hospitalized with acute non-bloody, non-mucoid diarrhoea, 69 (22·8%) had polymicrobial infection, including 52 (17·2%) multiple viral infection and 17 (5·6%) viral and bacterial co-infection. Rotavirus had the most important role in both categories; thus the control of rotavirus infection is crucial for maintaining children's health in Taiwan.

A total of 90 rotavirus-positive faecal specimens collected from patients hospitalized with diarrhoea in 1990–1994 (n=77) and 2000–2002 (n=13) were investigated for VP7 and VP4 genotypes. The specimens included 21 typable and 69 non-reactive or multireactive rotavirus strains as monitored by monoclonal antibody-based serotyping ELISA. Genotyping was carried out by multiplex PCR/sequencing using primers specific for both VP7 and VP4 genes. The contribution of common genotypes (G1P[8], G2P[4], G3P[8], G4P[8]) in causing rotavirus diarrhoea was 79·2% and 92·3% in the years 1990–1994 and 2000–2002, respectively, while G9P[8] infections were detected at lower levels (1·3% and 7·7%) at both time-points. There was a predominance of G1P[8] in 1990–1994 and of G2P[4] in 2000–2002. The detection of unusual rotavirus strains (G1P[6], G1P[4], G1P[19], G2P[8], G3P[4], G4P[6]) in 19·5% of the patients indicated a significant contribution of reassortants in causing diarrhoea in western India.

The aim of this study was to determine the burden, management and outcomes of rotavirus infection in young children presenting to a tertiary paediatric hospital in Sydney, Australia. All laboratory-confirmed cases of rotavirus in children aged <5 years were identified and medical records reviewed. In 2004, 80 children aged <5 years presented to the hospital with rotavirus gastroenteritis confirmed by stool testing. Infants aged <24 months comprised 75% of cases, with more males than females affected. Most children (86%) acquired rotavirus infection in the community, with a mean length of hospital admission of 2·3 days. There were eight cases of nosocomial infection at a rate of 3/10 000 admissions. The rates of intravenous fluid management (46%) and antibiotic use (28%) were high, reflecting the severity of disease presenting in a hospital setting. These data will help inform the assessment of the recently introduced rotavirus vaccination programme in Australia.

Diarrhoeal illnesses are the most frequent of notifiable diseases in Aragon. Physicians notify diarrhoea cases with presumed infectious origin on a weekly basis. Following an increase in 2005–2006, we aimed to identify the responsible organism(s) in order to inform control measures. We described seasonality of diarrhoea notifications for 1998–2004 and 2005–2006. We calculated correlations between diarrhoea notifications and enteric pathogens diagnosed in two Aragonese laboratories, and applied linear regression using coefficients of determination (r2). In 2005–2006 the winter peak of diarrhoea notifications increased from 2494 to 3357 weekly cases (34·6%) and the peak in Rotavirus diagnoses from 15 to 39 weekly cases. The correlation of diarrhoea notifications with Rotavirus was 0·05 in 1998–2004 and 0·42 in 2005–2006. The model for 1998–2004 included Salmonella enterica, Giardia lamblia and Clostridium difficile (r2=0·08) and for 2005–2006 Rotavirus and Astrovirus (r2=0·24). Our results suggest that Rotavirus contributed to the increase of diarrhoea notifications. We recommend determining the disease burden of Rotavirus in order to guide vaccination policies.

This study investigates whether a child's risk of rotavirus diarrhoea is associated with season of birth in England and Wales, countries where rotavirus infections are highly seasonal. Poisson regression models were fitted to weekly counts of laboratory-confirmed rotavirus infections from children aged <5 years born between 1998 and 2007. In the first year of life, the risk of a laboratory-confirmed rotavirus infection was significantly higher for children born in summer compared with winter [relative risk (RR) 2·13, 95% confidence interval (CI) 2·07–2·19]. In the second to fifth years of life, the pattern reversed (second year of life: RR 0·73, 95% CI 0·71–0·75). The cumulative risk up to age 5 years remained significantly higher for children born in summer compared with winter due to the increased risk for summer births during their first year of life. Maternal immunity and age-specific levels of exposure to rotavirus could explain our findings.

To inform current and future vaccination strategies, we describe the seroepidemiology of hepatitis B virus (HBV) infection in ten representative European countries using standardized serology that allowed international comparisons. Between 1996 and 2003, national serum banks were compiled by collecting residual sera or by community sampling; sera were then tested by each country using its preferred enzyme immunoassays and testing algorithm, and assay results were standardized. Information on current and past HBV vaccination programmes in each country was also collected. Of the ten countries, six reported low levels (<3%) of antibodies against HBV core antigen (anti-HBc). Of the eight countries testing for HBV surface antigen (HBsAg), the highest prevalence was reported in Romania (5·6%) and in the remaining seven countries prevalence was <1%. Universal HBV vaccination programmes had been established in seven countries as recommended by the World Health Organization, but the seroprevalence of antibodies against HBsAg (anti-HBs) was lower than the reported vaccine coverage in three countries. Regular serological surveys to ascertain HBV status within a population, such as reported here, provide important data to assess the need for and to evaluate universal HBV vaccination programmes.

In the last decade, a declining prevalence of HCV infection has been described in injecting drug users (IDUs) in different countries. This study is the first to assess temporal trends in drug-injecting patterns, HCV infection rates and viral genotype distribution in 770 Brazilian IDUs, recruited by two cross-sectional studies (1994–1997 and 1999–2001). A substantial decline in the prevalence of HCV infection was found over the years (75% in 1994 vs. 20·6% in 2001, P<0·001) that may be a consequence of the significant reduction in the overall frequencies of drug injection and needle-sharing, as well as the participation of IDUs in initiatives aimed at reducing drug-related harm. No trend was found in terms of viral genotype distribution. Despite the favourable scenario, preventive measures must be maintained, especially in vulnerable subgroups such as young or new injectors, where risky behaviours through direct and indirect sharing practices remain common.

Surveillance reports and prevalence studies have indicated that injecting drug users (IDUs) contribute more to the hepatitis C epidemic in the United Kingdom than any other risk group. Information on both the prevalence and incidence of hepatitis C in IDUs is therefore essential to understanding the epidemiology of this infection. The prevalence of hepatitis C in specimens from the Unlinked Anonymous Prevalence Monitoring Programme collected in 1995, 1996, 1998, 1999, 2000, and 2001 was determined using residual syphilis serology specimens from IDUs attending 15 genitourinary medicine (GUM) clinics in and outside London. These specimens were tested for antibodies to hepatitis C virus (anti-HCV). Using this cross-sectional design, anti-HCV-negative specimens were tested for HCV RNA to identify incident infections during the ‘window’ period of infection, and thus to estimate HCV incidence. Results of the multivariable analysis showed that there was marked variation in prevalence by clinic (P<0·0001) and age (P<0·0001). Overall the majority of infections were in males and the overall prevalence in injectors declined over the study period from 36·9% to 28·7%. The annual incidence in these injectors was estimated as being 3·01% (95% CI 1·25–6·73). Over the study period HCV incidence decreased by 1·2% per year. Genotyping of the incident infections identified the most common genotype as type 1 with type 3 being more frequently seen after 1998. Of the prevalent infections, genotype 1 was the most common. The study has confirmed a higher prevalence of anti-HCV in IDUs in the London area compared to those outside London. How representative of the current injecting drug user population are IDUs attending GUM clinics is unclear. Even so, such studies allow prevalence and incidence to be estimated in individuals who have ever injected drugs and inform ongoing public health surveillance.

Strategies to lessen the impact of pandemic influenza include behavioural modifications of the general public regarding medical care, personal hygiene and protection, and social distancing. We conducted a telephone survey of Beijing residents to evaluate potential behavioural changes in the general public in the event of an influenza pandemic occurring. We used a two-stage Mitofsky–Waksberg telephone survey of Beijing residents aged ⩾15 years. The sample was weighted to reflect the 2000 census. We asked the respondents about their current healthcare-seeking behaviours for influenza-like illness (ILI), protective measures (personal hygiene, social distancing), and compliance with health authorities. We then asked what they would do during a hypothetical pandemic. We interviewed 256 Beijing participants in our study (response rate 56%). The percent of participants consulting a doctor for ILI rose from the current 41% [95% confidence interval (CI) 35–47] to 74% (95% CI 68–79) during a pandemic. Fifty-five percent (95% CI 48–62) of the participants would seek care from a more specialized hospital during a pandemic than currently. More than 90% of the participants reported already practising hand-washing or covering their coughs or sneezes during a non-pandemic period; this percentage changed little under a pandemic scenario. Compared to the current social distancing practices, more people would avoid crowded places (77% vs. 92%, P<0·01), use a mask outside the home (10% vs. 58%, P<0·01), and take time off from work or school (17% vs. 38%, P<0·01) during a pandemic. Moreover, 26% of the participants (95% CI 21–32) would stockpile food or water, and 55% (95% CI 49–61) would stockpile medicines. Some of the behavioural changes reported by Beijing participants might help to alleviate the damage caused by a potential pandemic. However, increased use of medical care at referral hospitals will further strain the healthcare system during a pandemic.

This study primarily aimed to estimate the association between influenza vaccination and the occurrence of hospitalization for acute respiratory or cardiovascular diseases, or all-cause death during the influenza season in an elderly population in South Africa. We conducted a nested case-control study using data from a cohort of 45 522 elderly members of a private medical funding organization during the moderate 2004 influenza season. In 1282 (2·8%) subjects the combined outcome occurred and the influenza vaccination rate in controls was 15·4%. After adjustments for measured confounders, vaccination was associated with a statistically significant reduction of 19% (95% confidence interval 3·1–32·9) in the combined outcome. Post-hoc sensitivity analysis of the potential impact of potential healthy user bias showed that confounding, if present, could have caused this finding. Our data were inconclusive regarding the benefits of influenza vaccination in elderly persons in South Africa and given the low vaccine uptake, long-term follow-up is warranted.

This study examined the impact of meteorological conditions on sporadic, community-acquired cases of Legionnaires' disease in England and Wales (2003–2006), with reference to the 2006 increase in cases. A case-crossover methodology compared each case with self-controlled data using a conditional logistic regression analysis. Effect modification by quarter and year was explored. In total, 674 cases were entered into the dataset and two meteorological variables were selected for study based on preliminary analyses: relative humidity during a case's incubation period, and temperature during the 10–14 weeks preceding onset. For the quarter July–September there was strong evidence to suggest a year, humidity and temperature interaction (Wald χ2=30·59, 3 d.f., P<0·0001). These findings have implications for future case numbers and resource requirements.

A total of 522 Danish blood donors were followed during 2004–2005 to describe the seroepidemiology of Legionella infections in healthy individuals from a general population. Antibodies to Legionella spp. were measured by indirect immunofluorescence antibody test. The prevalence of Legionella antibodies (titre ⩾1:128) was 26·8% and remained fairly constant during the year of follow-up. However, 6·9% of the blood donors developed a fourfold or greater rise in antibody titres. A history of visits to Danish summer cottages was associated with both Legionella seropositivity (OR 1·53, 95% CI 1·02–2·30) and seroconversion (OR 2·66, 95% CI 1·21–5·83). There were no consistent associations between either levels of antibody titres or seroconversion and self-reported health symptoms, absence from work due to illness, or to any risk factors. We conclude that community-acquired Legionella infections are frequent; however, they rarely result in severe illness.

The worldwide spread of severe acute respiratory syndrome (SARS) raised questions about the risk of importation of such infection, in particular by air travel. Entry screening was implemented in some countries although poor evidence on its effectiveness is reported. We developed a model to estimate the number of imported SARS cases between regions, using the 2003 SARS epidemic data to apply this model for two scenarios: from Beijing to Frankfurt and from Hong Kong to London. We back-calculated the data to estimate individuals’ time of infection and built a model where every individual has a probability of being isolated, of traveling, and of being undetected at arrival. The findings, consistent with what was observed in 2003, suggest that entry screening does not affect the predicted number of imported cases. Inversely, importation depends on the transmission dynamic in the country of origin (including control measures in place) and on the intensity of air travel between regions.

Human bocavirus (HBoV) was recently identified in respiratory samples from patients with acute respiratory infections and has been reported in different regions of the world. To the best of our knowledge, HBoV has never been reported in respiratory infections in Brazil. Nasopharyngeal aspirates were collected from patients aged <5 years hospitalized in 2005 with respiratory infections in Ribeirão Preto, southeast Brazil, and tested by polymerase chain reaction (PCR) for HBoV. HBoV-positive samples were further tested by PCR for human respiratory syncytial virus, human metapneumovirus, human coronaviruses 229E and OC43, human influenza viruses A and B, human parainfluenza viruses 1, 2 and 3, human rhinovirus and human adenovirus. HBoV was detected in 26/248 (10·5%) children of which 21 (81%) also tested positive for other respiratory viruses. Despite the high rates of co-infections, no significant differences were found between HBoV-positive patients with and without co-infections with regard to symptoms.

A 15-month survey of 412 bloodstream yeast isolates from 54 Belgian hospitals was undertaken. Candida albicans was the most common species (47·3%) followed by C. glabrata (25·7%), C. parapsilosis (8·0%), C. tropicalis (6·8%) and Saccharomyces cerevisiae (5·1%). Common predisposing factors were antibacterial therapy (45%), hospitalization in intensive care units (34%), presence of in-dwelling catheters (32%), underlying cancer (23%) and major surgery (11%). Most patients had more than one predisposing factor. Fluconazole alone or in combination with another antifungal agent was the treatment of choice for 86·6% of the cases. Susceptibility testing revealed that 93·5% were susceptible to amphotericin B, 39·6% to itraconazole, 42·8% to fluconazole and 87% to voriconazole. Resistance to azoles was more common among C. glabrata isolates.

An open-label, prospective cohort, active healthcare-associated infection surveillance sequential study was conducted in four Italian intensive-care units. The aim was to determine the effect of switching from open (glass) to closed fully collapsible plastic intravenous (i.v.) infusion containers (Viaflo®) on rate and time to onset of central venous catheter-associated bloodstream infections (CVC-BSI). A total of 1173 adult patients were enrolled. The CVC-BSI rate during the open container period was significantly higher than during the closed container period (8·2 vs. 3·5 BSI/1000 CVC days, relative risk 0·43, 95% confidence interval 0·22–0·84, P=0·01). The probability of developing a CVC-BSI was assessed over time comparing open and closed i.v. infusion containers. In the closed container period, it remained fairly constant (0·8% at days 1–3 to 1·4% at days 7–9) whereas during the open container period it increased (2% at days 1–3 to 5·8% at days 7–9). Overall, the chance of acquiring a CVC-BSI significantly decreased by 61% in the closed container period (Cox proportional hazard ratio 0·39, P=0·004).

Streptococcus pneumoniae strains causing invasive pneumococcal disease (IPD) in the elderly population of England and Wales during the winter of 2003/2004 (1 November 2003 to 30 April 2004) were characterized by serotyping and genotyping in order to determine their population structure in the elderly. Serotyping and multilocus sequence typing (MLST) were carried out on 542 invasive isolates referred to the Respiratory and Systemic Infection Laboratory. Pneumococci were distributed among 32 serotypes and 144 MLST sequence types. A high genetic diversity was observed within the major serotypes. Genetic relatedness varied with regard to serotype. Isolates within serotypes 3, 7F and 8 were the most genetically related whereas serotypes 6A and 19F comprised isolates originating from unrelated ancestors. There was indirect evidence that some pneumococci were derived from clones that had undergone capsular switching in the past. Interestingly one case of IPD was caused by a pneumococcus originating from a clone that had undergone capsular switching from serotype 18C, a serotype included in 7-valent pneumococcal conjugate vaccine (PCV) to serotype 1 (serotype not included in PCV) suggesting that virulent clones with the potential ability to evade PCV existed in the pneumococcal population prior to the routine introduction of this vaccine. Isolates from 28 cases of apparent 23-valent pneumococcal polysaccharide vaccine (PPV) failure were included but there was no evidence of the emergence of particular clones associated with vaccine failures. Longitudinal studies based on serotypic and genetic characterization of pneumococci are fundamental to understanding the impact of both PPV and PCV on the genetic structure of pneumococcal populations.