The aims of this study were to describe the trend of acquired syphilis in the city of Florence and its province over a 7-year period, to investigate sexual behaviours in the syphilis-infected population and to analyse syphilis/HIV co-infection. A total of 259 patients were classified according to age, sex and HIV infection. We estimated that from 2004 to 2008 cases increased by 248%. Most patients with concurrent HIV infection were male (31–45 years), but 40- to 60-year-old men who had sex with men predominated in both male and HIV-positive patients. Oral sex was identified as the most significant route of transmission, although most patients did not consider it so. Late-presenters with HIV accounted for 33% of HIV-positive patients: they were unaware of their HIV status and showed syphilis lesions only. In these cases, syphilis heralded the presence of HIV infection and allowed earlier diagnosis.

Seventy-five clinical isolates of Pseudomonas aeruginosa collected in a tertiary teaching hospital in Thailand were investigated for susceptibility to antimicrobials including imipenem. Metallo-β-lactamase (MBL) enzymes were detected by E-test MBL assay and PCR; class 1 integron genes were also detected by PCR. Strains positive for blaIMP and blaVIM genes were further characterized by DNA sequencing and examined for clonality by pulsed-field gel electrophoresis. High rates of resistance to anti-pseudomonal agents were found. MBL enzymes were found in 13 (17·3%) strains and 24 (32%) carried class 1 integron genes. Twelve of the latter strains harboured the blaIMP-14 gene and one strain the blaVIM-2 gene. All of the IMP-14 strains were identical or closely related suggesting clonal dissemination of these genes.

Unprecedented high rates of anthrax outbreaks have been observed recently in cattle and humans in Bangladesh, with 607 human cases in 2010. By enrolling 15 case and 15 control cattle smallholdings in the spatial zone in July–September 2010, we conducted a case-control study, data of which were analysed by matched-pair analysis and multivariable conditional logistic regression. Feeding animals with uprooted and unwashed grass [odds ratio (OR) 41·2, 95% confidence interval (CI) 3·7–458·8, P=0·003], and feeding water hyacinth (Eichhornia crassipes) (OR 22·2, 95% CI 1·2–418·7, P=0·039) were independent risk factors for anthrax in cattle.

The analysis of contact networks plays a major role to understanding the dynamics of disease spread. Empirical contact data is often collected using contact diaries. Such studies rely on self-reported perceptions of contacts, and arrangements for validation are usually not made. Our study was based on a complete network study design that allowed for the analysis of reporting accuracy in contact diary studies. We collected contact data of the employees of three research groups over a period of 1 work week. We found that more than one third of all reported contacts were only reported by one out of the two involved contact partners. Non-reporting is most frequent in cases of short, non-intense contact. We estimated that the probability of forgetting a contact of ⩽5 min duration is greater than 50%. Furthermore, the number of forgotten contacts appears to be proportional to the total number of contacts.

The relationship between the level of antibodies in bulk tank milk (BTM) and the within-herd seroprevalence of Coxiella burnetii in cows was assessed. Blood from milking cows and BTM were sampled in 55 infected herds and tested using commercial enzyme-linked immunosorbent assay (ELISA) kits. The relationship between antibody levels and WHP, which was quantified using a general linear model, was only moderate (R 2=0·15). Nevertheless, the lowest antibody level in BTM was associated with the lowest mean within-herd prevalence. The present finding indicates that ELISA applied to BTM could identify infected herds with quite low within-herd seroprevalence. For such herds, the vaccination of dairy cows as well as nulliparous heifers using a phase I vaccine could effectively prevent C. burnetii shedding.

A scoping study and systematic review-meta-analyses (SR-MAs) were conducted to evaluate the effectiveness of various interventions for Salmonella in broiler chicken, from grow-out farm to secondary processing. The resulting information was used to inform a quantitative exposure assessment (QEA) comparing various control options within the context of broiler chicken production in Ontario, Canada. Multiple scenarios, including use of two separate on-farm interventions (CF3 competitive exclusion culture and a 2% lactose water additive), a package of processing interventions (a sodium hydroxide scald water disinfectant, a chlorinated post-evisceration spray, a trisodium phosphate pre-chill spray and chlorinated immersion chilling) a package consisting of these farm and processing interventions and a hypothetical scenario (reductions in between-flock prevalence and post-transport concentration), were simulated and compared to a baseline scenario. The package of on-farm and processing interventions was the most effective in achieving relative reductions (compared to baseline with no interventions) in the concentration and prevalence of Salmonella by the end of chilling ranging from 89·94% to 99·87% and 43·88% to 87·78%, respectively. Contaminated carcasses entering defeathering, reductions in concentration due to scalding and post-evisceration washing, and the potential for cross-contamination during chilling had the largest influence on the model outcomes under the current assumptions. Scoping study provided a transparent process for mapping out and selecting promising interventions, while SR-MA was useful for generating more precise and robust intervention effect estimates for QEA. Realization of the full potential of these methods was hampered by low methodological soundness and reporting of primary research in this area.

West Nile virus (WNV) is a mosquito-borne flavivirus which circulates in birds, horses and humans. An estimated 80% of WNV infections are asymptomatic. Fewer than 1% of infected persons develop neuroinvasive disease, which typically presents as encephalitis, meningitis, or acute flaccid paralysis. This study was conducted from January 2008 to June 2009 in Isfahan, Iran. Patients attending the emergency department with fever and loss of consciousness were consecutively included. Cerebrospinal fluids (CSF) were initially analysed through bacteriology and biochemistry examinations, resulting in those with evidence of meningitis being excluded. Patients' CSF and serum were diagnosed by serological and molecular assays. A total of 632 patients with fever and loss of consciousness were tested by CSF analyses. Samples of the remaining patients (39·4%) were referred for WNV investigation. Three (1·2%) of the patients were positive for both serum and CSF by RT–PCR, and six (2·4%) were positive only for IgG antibodies. History of insect bite, and blood transfusion and transplantation were risk factors for being positive by RT–PCR (P=0·048) and being IgG positive (P=0·024), respectively. The results of this study showed that the prevalence of West Nile fever is low in patients with encephalitis.

The aim of this study was determine the prevalence of Mycoplasma hominis, M. genitalium, M. fermentans, M. pirum, M. penetrans and Ureaplasma urealyticum in HIV-infected patients. Culture and PCR were used to detect six species of Mycoplasma in first-void urine of HIV-1 infected men. A total of 497 HIV/AIDS patients (age range 5–75 years, mean 37 years) were screened in the study. All presented positive for at least one kind of mycoplasma, especially U. urealyticum and M. hominis. Six mycoplasmas were significant in the homosexual contact and heterosexual contact groups. The distribution of M. hominis, M. penetrans, and M. pirum were significantly different in this four-transmission category. CD4+ cell count levels were lower in the AIDS-associated Mycoplasma-positive group than in the Mycoplasma-negative group (P<0·01). This study indicates that U. urealyticum, M. hominis and M. fermentans are prevalent in HIV-1-infected male patients. This may be an indication of whether mycoplasmas are co-factors in the progression of HIV disease.

Infectious mononucleosis is a clinical manifestation of primary Epstein–Barr virus infection. It is unknown whether genetic factors contribute to risk. To assess heritability, we compared disease concordance in monozygotic to dizygotic twin pairs from the population-based California Twin Program and assessed the risk to initially unaffected co-twins. One member of 611 and both members of 58 twin pairs reported a history of infectious mononucleosis. Pairwise concordance in monozygotic and dizygotic pairs was respectively 12·1% [standard error (s.e.)=1·9%] and 6·1% (s.e.=1·2%). The relative risk (hazard ratio) of monozygotic compared to dizygotic unaffected co-twins of cases was 1·9 [95% confidence interval (CI) 1·1–3·4, P=0·03], over the follow-up period. When the analysis was restricted to same-sex twin pairs, that estimate was 2·5 (95% CI 1·2–5·3, P=0·02). The results are compatible with a heritable contribution to the risk of infectious mononucleosis.

This study describes the results of the health programme implemented in the Valencian Community (Spain) to achieve an early diagnosis of Chagas disease in pregnant Latin American women and their newborns. During 2009 and 2010, 1975 women living in the health districts of three university hospitals were enrolled via midwives or at the time of delivery. Diagnosis of disease was performed using two serological tests with different antigens. Congenital infection was diagnosed by parasitological, molecular or serological methods from blood samples obtained at birth or in subsequent controls. The overall seroprevalence of Chagas infection in pregnant women from 16 different endemic countries was 11·4%. Infection was higher in those from countries in the Gran Chaco Region (Bolivia, 34·1%; Paraguay, 7·4%; Argentina, 5·3%). Eight newborn infants from Bolivian mothers had congenital Chagas which represents a vertical transmission rate of 3·7%. In conclusion, this work supports the benefits of offering an early diagnosis to pregnant women and newborns during routine prenatal healthcare.

Sporadic community-acquired legionellosis (SCAL) can be acquired through contaminated aerosols from residential potable water. Electricity-dependent hot-water tanks are widely used in the province of Quebec (Canada) and have been shown to be frequently contaminated with Legionella spp. We prospectively investigated the homes of culture-proven SCAL patients from Quebec in order to establish the proportion of patients whose domestic potable hot-water system was contaminated with the same Legionella isolate that caused their pneumonia. Water samples were collected in each patient's home. Environmental and clinical isolates were compared using pulsed-field gel electrophoresis. Thirty-six patients were enrolled into the study. Legionella was recovered in 12/36 (33%) homes. The residential and clinical isolates were found to be microbiologically related in 5/36 (14%) patients. Contaminated electricity-heated domestic hot-water systems contribute to the acquisition of SCAL. The proportion is similar to previous reports, but may be underestimated.

The effectiveness of environmental decontamination (ED) as a measure in the control of infectious diseases is controversial. This work quantifies the effectiveness of ED by analysing the transmission of pathogens from the environment to susceptible hosts in a Susceptible–Infected–Susceptible model. Analysis of the model shows that ED can render a population disease-free only when the duration of infection (D) is within a certain range. As host-to-host transmission rate is increased, D falls outside this range and the higher levels of ED have a diminishing return in reducing the number of infected hosts at endemic equilibrium. To avoid this, ED can be combined with other control measures, such as treating infected individuals to push the duration of infection into the specified range. We propose decision criteria and minimum ED efforts required for control policies to be effective.