In this case-control study, cases [community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA), n=79] and controls [community-associated methicillin-susceptible S. aureus (CA-MSSA), n=36] were defined as a laboratory-confirmed infection in a patient with no previous hospital-associated factors. Skin and soft tissue were the predominant sites of infection, both for cases (67·1%) and controls (55·6%). Most of the cases (79·7%) and controls (77·8%) were aged <30 years. Investigations did not reveal any significant statistical differences in acquiring a CA-MRSA or CA-MSSA infection. The most common shared risk factors included overcrowding, previous antibiotic usage, existing skin conditions, household exposure to someone with a skin condition, scratches/insect bites, and exposure to healthcare workers. Similar risk factors, identified for both CA-MRSA and CA-MSSA infections, suggest standard hygienic measures and proper treatment guidelines would be beneficial in controlling both CA-MRSA and CA-MSSA in remote communities.

Estimates of the burden of foodborne disease rely on attributing a proportion of syndromic gastroenteritis to foodborne transmission. Persons with syndromic diarrhoea/vomiting can also present with concurrent respiratory symptoms that could be due to respiratory infections, gastrointestinal infections, or both. This distinction is important when estimating the foodborne disease burden but has rarely been considered. Using data from population surveys from Australia, Canada and the USA we describe the effect of excluding persons with respiratory and associated symptoms from the case definition of gastroenteritis. Excluding persons first with respiratory symptoms, or second with respiratory symptoms plus fever and headache, resulted in a decrease in the weighted estimates of acute gastroenteritis of about 10–50% depending on the exclusion criteria. This has the potential to have a very significant impact on estimates of the burden of foodborne infections using syndromic case definitions of acute gastroenteritis.

Between January 2006 and May 2008, 2624 pregnant S. Korean women between 35–37 weeks gestation were screened for group B streptococcus (GBS). Resistance to antimicrobials was tested by disk diffusion and serotype determined using co-agglutination assays and microarray methods. Overall, 8% of pregnant women were colonized. Serotype III was the predominant serotype (43·8%), followed by serotypes V (20·3%), Ia (12·1%), and Ib (9·5%). GBS was frequently resistant to clindamycin (54·0%) and erythromycin (25·6%); 3·7% were resistant to cefazolin. More than three-quarters of serotype V were resistant to clindamycin or erythromycin or both, and 71% of serotype III were resistant to clindamycin but only 12% were resistant to erythromycin. GBS prevalence exceeded earlier reports by one-third. This is the first report of cefazolin resistance in Korea. These results underscore the need to establish screening measures and chemoprophylaxis guidelines regarding GBS infections in Korea.

A capture–recapture study was undertaken to estimate the incidence and likely total burden of malaria cases in England. Cases diagnosed by the national Malaria Reference Laboratory (MRL) between July 2003 and December 2004 were matched with cases reported to Hospital Episode Statistics using demographic, geographical, parasitological, and temporal information. A total of 3861 cases were recorded in one or both datasets; the ‘unknown population’ was estimated as 746 cases (95% CI 677–822) giving a total of 4607 cases (95% CI 4446–4767) over 18 months. Eighty-four percent (95% CI 83–85) of cases were recorded in one or both datasets. Fifty-six percent (95% CI 54–58) of cases were captured by the MRL surveillance system; ascertainment for Plasmodium falciparum and London cases was higher at 66% and 62%, respectively. Improving case ascertainment will facilitate effective measures to reduce the burden of this preventable disease in the UK.

We constructed a syndromic surveillance system to collect directly information on daily health conditions directly from local residents via the internet [web-based daily questionnaire for health surveillance system (WDQH SS)]. This paper considers the feasibility of the WDQH SS and its ability to detect epidemics. A verification study revealed that our system was an effective surveillance system. We then applied an improved WDQH SS as a measure against public health concerns at the G8 Hokkaido Toyako Summit meeting in 2008. While in operation at the Summit, our system reported a fever alert that was consistent with a herpangina epidemic. The highly mobile WDQH SS described in this study has three main advantages: the earlier detection of epidemics, compared to other surveillance systems; the ability to collect data even on weekends and holidays; and a rapid system set-up that can be completed within 3 days.

Estimation of prevalence of disease, including construction of confidence intervals, is essential in surveys for screening as well as in monitoring disease status. In most analyses of survey data it is implicitly assumed that the diagnostic test has a sensitivity and specificity of 100%. However, this assumption is invalid in most cases. Furthermore, asymptotic methods using the normal distribution as an approximation of the true sampling distribution may not preserve the desired nominal confidence level. Here we proposed exact two-sided confidence intervals for the prevalence of disease, taking into account sensitivity and specificity of the diagnostic test. We illustrated the advantage of the methods with results of an extensive simulation study and real-life examples.

To assess the prevalence of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) colonization in HIV-1-infected men who have sex with men (MSM), a cross-sectional study was conducted on 104 persons attending a large STI/HIV unit in Rome, Italy in the period June 2007–June 2008. Swabs obtained from both anterior nares and S. aureus isolates were characterized by phenotypic and genotypic methods. A total of 24 individuals (23·1%) were colonized with S. aureus but none carried MRSA. No statistically significant association between colonization with S. aureus and behavioural, clinical, virological or immunological characteristics was identified. This study indicates a lack of circulation of CA-MRSA in HIV-1-infected MSM in Italy and underscores large epidemiological differences between the USA and a European country, so that only locally conducted epidemiological studies can provide insight into the local circulation of CA-MRSA in general and selected populations.

Although pneumonia is a leading cause of death from infectious disease worldwide, comprehensive information about its causes and incidence in low- and middle-income countries is lacking. Active surveillance of hospitalized patients with pneumonia is ongoing in Thailand. Consenting patients are tested for seven bacterial and 14 viral respiratory pathogens by PCR and viral culture on nasopharyngeal swab specimens, serology on acute/convalescent sera, sputum smears and antigen detection tests on urine. Between September 2003 and December 2005, there were 1730 episodes of radiographically confirmed pneumonia (34·6% in children aged <5 years); 66 patients (3·8%) died. A recognized pathogen was identified in 42·5% of episodes. Respiratory syncytial virus (RSV) infection was associated with 16·7% of all pneumonias, 41·2% in children. The viral pathogen with the highest incidence in children aged <5 years was RSV (417·1/100 000 per year) and in persons aged ⩾50 years, influenza virus A (38·8/100 000 per year). These data can help guide health policy towards effective prevention strategies.

Burkholderia pseudomallei, the causative agent of melioidosis is associated with soil. This study used a geographic information system (GIS) to determine the spatial distribution of clinical cases of melioidosis in the endemic suburban region of Townsville in Australia. A total of 65 cases over the period 1996–2008 were plotted using residential address. Two distinct groupings were found. One was around the base of a hill in the city centre and the other followed the old course of a major waterway in the region. Both groups (accounting for 43 of the 65 cases examined) are in areas expected to have particularly wet topsoils following intense rainfall, due to soil type or landscape position.

A series of simulation experiments was conducted to determine how estimates of the latent and infectious periods, number of neighbours (contacts) and population size impact on the predicted magnitude and distribution of foot-and-mouth disease (FMD) outbreaks in white-tailed deer in southern Texas. Outbreaks were simulated using a previously developed and applied susceptible–latent–infected–recovered geographic automata model. There were substantial differences in the estimated predicted number of deer and locations infected, based on the model parameters used (3779–119 879 deer infected and 227–6526 locations affected). There were also substantial differences in the spatial risk of infection based on the model parameters used. The predicted spread of FMD was found to be most sensitive to the assumed latent period and the assumed number of contacts. How these parameters are estimated is likely to be critical in studies on the impact of FMD spread in situations in which wildlife reservoirs might potentially exist.

It has recently been reported that the worldwide increase in the number of pertussis cases is a result of the waning of whole-cell vaccine-induced immunity. Thus, in this study, we aimed to investigate the pertussis immunity status of primary and secondary school students in a district of Ankara, Turkey. A total of 997 healthy students, aged 9–17 years, who had been immunized with four doses of whole-cell pertussis vaccine were included in the study. The subjects were divided into two age groups: 9–14 and 15–17 years. To determine the immune status, serum levels of IgG anti-pertussis toxin (aPT) antibody were tested by in-house ELISA and arbitrarily evaluated as non-immune [<10 ELISA units (EU)/ml], immune (10–100 EU/ml), and recent infection (>100 EU/ml). Serum samples of 997 students (559 females, 438 males) aged between 9 and 17 years (mean 13·02±2·25, median 13 years) were tested. Non-immune, immune and recent infection levels of aPT were found in 27·3%, 59·3% and 13·4% of individuals, respectively. The immune group did not have statistically significant differences between males and females (P=0·68). In the 9–14 and 15–17 years age groups, serum aPT antibody levels ⩾10 EU/ml were 73·1% and 72·2%, respectively, which did not represent any statistical difference (P=0·81). Students aged 15–17 years had a higher immunity rate than the 9–14 years group, and the percentage of students with recent infection in the 9–14 years group was higher than the 15–17 years group (P<0·001). The peak age of non-immunized subjects was 9 years (47·0%), and decreased to a minimum at age 12–13 years, and began to increase again from age 13–14 years. In contrast, the ratio of recent infection was least at age 9–10 years, began to increase, and reached a peak at 12 years, and then decreased. On the other hand, it was observed that household size and monthly income were not associated with the immunity status (P=0·65, P=0·37, respectively). The results of the present study show that levels of antibody against pertussis decreased in the younger age groups and, as a result, there is an increase in the number of pertussis cases. Thus, in order to decrease the incidence of pertussis and protect infants, we recommend the application of booster doses at regular intervals.

To characterize the association between county-level risk factors and the incidence of mumps in the 2006 Iowa outbreak, we used generalized linear mixed models with the number of mumps cases per county as the dependent variable. To assess the impact of spring-break travel, we tested for differences in the proportions of mumps cases in three different age groups. In the final multivariable model, the proportion of Iowa's college students per county was positively associated (P<0·0001) with mumps cases, but the number of colleges was negatively associated with cases (P=0·0002). Thus, if the college students in a county were spread among more campuses, this was associated with fewer mumps cases. Finally, we found the proportion of mumps cases in both older and younger persons increased after 1 April (P=0·0029), suggesting that spring-break college travel was associated with the spread of mumps to other age groups.

In an epidemiological survey from South India, 936 serum samples were tested for IgG against recombinant baculovirus-expressed VP6 proteins from human group A and group C rotaviruses. The overall seroprevalence for group A was 100% and for group C was 25·32% (95% CI 22·64–28·21). The lowest seroprevalence for group C was in children aged <10 years (16·79%). An age-related rise in seroprevalence in group C, but not group A, suggests different patterns of exposure. Seroprevalence was similar in rural and urban subjects, unlike the higher prevalence in rural subjects in studies elsewhere.

To determine methicillin-resistant Staphylococcus aureus (MRSA) carriage in poultry and slaughterhouse personnel, 40 Dutch broiler flocks, in six slaughterhouses and 466 personnel were sampled. Of the employees, 26 were positive (5·6%), indicating a higher risk of exposure when compared to the general Dutch population (0·1%). This risk was significantly higher for personnel having contact with live animals (5·2%) – especially hanging broilers on the slaughterline (20·0%) – than for all other personnel (1·9%). Conventional electric stunning conferred a significantly higher risk of MRSA carriage for employees than CO2 stunning (9·7% vs. 2·0%). A total of 405 broilers were sampled upon their arrival at the slaughterhouse, of which 6·9% were positive. These broilers originated from 40 Dutch slaughter flocks of which 35·0% were positive. MRSA contamination in the different compartments of slaughterhouses increased during the production day, from 8% to 35%. Of the 119 MRSA isolates, predominantly livestock-associated MRSA ST398 was found, although 27·7% belonged to ST9 (spa type t1430). There is an increased risk of MRSA carriage in personnel working at broiler slaughterhouses, particularly those having contact with live animals.

Pneumococcal meningitis is a subgroup of invasive pneumococcal disease with a case-fatality rate of up to 30% and long-term sequelae in more than 50% of cases in adults in developed countries. We aimed to determine risk factors for this particular form of pneumococcal disease. We conducted a prospective population-based laboratory study of invasive pneumococcal disease in adults in North-Rhine-Westphalia, Germany from February 2001 to August 2006. All isolates underwent serotyping and susceptibility testing at the National Reference Centre for Streptococci in Aachen, Germany. Data were analysed using multiple linear regression. A total of 1043 isolates from bacteraemia and 131 isolates from meningitis were included into the study. Serotype 23F and being female were independent risk factors for pneumococcal meningitis. Being ⩾60 years and serotype 1 were associated with a reduced odds ratio. Season, penicillin and macrolide resistance were not statistically associated with CNS involvement.

We determined the frequency of isolation of Leptospira from dogs and rodents, the serovars of Leptospira, and the clinical, gross and histological manifestations in dogs with leptospirosis in Trinidad. From dogs, samples of urine, blood and kidney were collected while only kidney and blood samples of trapped rodents were used. Isolates were cultured and serotyped using a panel of 23 international serovars and monoclonal antibodies. The risk factors for leptospirosis were also determined in owned dogs using a standard questionnaire. Of a total of 468 animals investigated for Leptospira, 70 (15·0%) were positive, comprising nine (18·0%) of 50 suspected canine leptospirosis cases, seven (3·4%) of 207 stray dogs and 54 (25·6%) of 211 rodents. The observation that rodents have a statistically (P<0·05, χ2) higher frequency of isolation emphasizes the importance of rodents as reservoirs of leptospirosis in the country. Copenhageni was the predominant serovar found in 100·0% (7/7), 33·3% (2/6) and 68·5% (37/54) of isolates from suspected canine leptospirosis cases, stray dogs and rodents, respectively. Serovars Icterohaemorrhagiae and Canicola, the two serovars present in the commercial vaccines used locally, were detected in one (1·5%) and zero (0·0%) isolates respectively of the 67 tested. Data provided suggest that the apparent vaccine failure may be a consequence of the fact that the predominant serovar (Copenhageni) detected in sick, apparently healthy dogs and in rodents is not contained in the vaccines used locally to protect dogs against canine leptospirosis.

Crimean Congo haemorrhagic fever (CCHF) has been an emerging tick-borne infection in some parts of Turkey since 2002, with a number of fatalities. Many of the initial non-specific symptoms of CCHF can mimic other common infections. Additionally, the seasonal pattern of the epidemic, and the waning attention of healthcare workers to the yearly index cases caused some delays in appropriate patient care and treatment. Between March 2004 and August 2008, 140 confirmed adult cases were evaluated retrospectively for initial diagnosis and treatment delays. This study clearly demonstrated that there are particular delays (4·8 days) in the referral system to initiate effective antiviral treatment in the tertiary-care centre which significantly affect fatality rates (P>0·05). A large number of patients (n=95, 68%) received an initial misdiagnosis of various infections other than CCHF. In conclusion, continuous medical education regarding CCHF in the epidemic area is essential in order to achieve a better survival rate from this deadly infection.