A recent countrywide MRSA spa-type 1081 outbreak in The Netherlands predominantly affected nursing homes, generating questions on how infection spreads within and between nursing homes despite a low national prevalence. Since the transfer of residents between nursing homes is uncommon in The Netherlands, we hypothesized that staff exchange plays an important role in transmission. This exploratory study investigated the extent of former (last 2 years) and current staff exchange within and between nursing homes in The Netherlands. We relied on a questionnaire that was targeted towards nursing-home staff members who had contact with residents. We found that 17·9% and 12·4% of the nursing-home staff formerly (last 2 years) or currently worked in other healthcare institutes besides their job in the nursing home through which they were selected to participate in this study. Moreover, 39·7% of study participants worked on more than one ward. Our study shows that, in The Netherlands, nursing-home staff form a substantial number of links between wards within nursing homes and nursing homes are linked to a large network of healthcare institutes through their staff members potentially providing a pathway for MRSA transmission between nursing homes and throughout the country.

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.

Despite being a vaccine-preventable disease for decades, pertussis control is still a public health challenge. A pertussis outbreak emerged in Jerusalem (n = 257 cases, January to June 2023). Most cases were young children (median age 1.5 years), and 100 were infants under 1 year. The hospitalisation rate of infants was 24%, which was considerably higher than that of cases aged 1 year and above (3.8%). There was one fatality in an unvaccinated, 10-week-old infant whose mother had not received pertussis vaccination during pregnancy. Most children were unvaccinated and resided in Jewish ultra-orthodox neighbourhoods in Jerusalem district. An intervention programme and vaccination campaign are ongoing.

The burden of community-associated Clostridium difficile infection (CA-CDI) has increased. We aimed to describe the epidemiology of CA-CDI to inform future interventions. We used population-based linked surveillance data from 2012 to 2016 to describe socio-demographic factors, ribotype and mortality for all CA (n = 1303) and hospital-associated (HA, n = 1356) CDI. For 483 community-onset (CO) CA-CDI and 287 COHA-CDI cases, a questionnaire on risk factors was completed and we conducted a case–case study using logistic regression models for univariate and multivariable analysis. CA-CDI cases had lower odds of being male (adjusted odds ratio (AOR) 0.71, 95% confidence interval (CI) 0.58–0.87; P < 0.001), and higher odds of living in rural rather than urban settlement (AOR 1.5, 95% CI 1.1–2.1; P = 0.05) compared with HA-CDI cases. The distribution of ribotypes was similar in both groups with RT078 being most prevalent. CDI-specific death was lower in CA-CDI than HA-CDI (7% vs. 11%, P < 0.001). COCA-CDI had lower odds of having had an outpatient appointment in the previous 4 weeks compared with COHA-CDI (AOR 0.61; 95% CI 0.41–0.9, P = 0.01) and lower odds of being in a care home or hospice when compared with their own home, than COHA-CDI (AOR 0.66; 95% CI 0.45–0.98 and AOR 0.35; 95% CI 0.13–0.92, P = 0.02). Exposure to gastric acid suppressants (50% in COCA-CDI and 55% in COHA-CDI) and antimicrobial therapy (18% in COCA-CDI and 20% in COHA-CDI) prior to CDI was similar. Our analysis of community-onset cases suggests that other risk factors for COHA-CDI may be equally important for COCA-CDI. Opportunities to safely reduce antibiotic and gastric acid suppressants use should be investigated in all healthcare settings.

Persistent methicillin-resistant Staphylococcus aureus (MRSA) infection in cystic fibrosis (CF) patients has been associated with a more rapid decline in lung function, increased hospitalisation and mortality. The aim of this study was to evaluate the clonal relationships among 116 MRSA isolates from 12 chronically colonised CF pediatric patients over a 6-year period in a Rio de Janeiro CF specialist centre. Isolates were characterised by antimicrobial resistance, SCCmec type, presence of Panton-Valentine Leukocidin (PVL) genes and grouped according to DNA macrorestriction profile by pulsed-field gel electrophoresis (PFGE) and spa gene type. High resistance rates were detected for erythromycin (78%) and ciprofloxacin (50%) and SCCmec IV was the most common type (72.4%). Only 8.6% of isolates were PVL positive. High genetic diversity was evident by PFGE (39 pulsotypes) and of nine that were identified spa types, t002 (53.1%) and t539 (14.8%) were the most prevalent. We conclude that the observed homogeneity of spa types within patients over the study period demonstrates the persistence of such strain lineages throughout the course of chronic lung infection.

Clostridium difficile diarrhoea is an urgent threat to patients, but little is known about the role of antibiotic administration that starts in emergency department observation units (EDOUs). We studied risk factors for antibiotic-associated diarrhoea (AAD) and C. difficile infection (CDI) in EDOU patients. This prospective cohort study enrolled adult patients discharged after EDOU antibiotic treatment between January 2013 and 2014. We obtained medical histories, EDOU treatment and occurrence of AAD and CDI over 28 days after discharge. We enrolled and followed 275 patients treated with antibiotics in the EDOU. We found that 52 (18·6%) developed AAD and four (1·5%) had CDI. Patients treated with vancomycin [relative risk (RR) 0·52, 95% confidence interval (CI) 0·3–0·9] were less likely to develop AAD. History of developing diarrhoea with antibiotics (RR 3·11, 95% CI 1·92–5·03) and currently failing antibiotics (RR 1·90, 95% CI 1·14–3·16) were also predictors of AAD. Patients with CDI were likely to be treated with clindamycin. In conclusion, AAD occurred in almost 20% of EDOU patients with risk factors including a previous history of diarrhoea with antibiotics and prior antibiotic therapy, while the risk of AAD was lower in patients receiving treatment regimens utilizing intravenous vancomycin.

Genomic epidemiology is routinely used worldwide to interrogate infectious disease dynamics. Multiple computational tools exist that reconstruct transmission networks by coupling genomic data with epidemiological models. Resulting inferences can improve our understanding of pathogen transmission dynamics, and yet the performance of these tools has not been evaluated for tuberculosis (TB), a disease process with complex epidemiology including variable latency and within-host heterogeneity. Here, we performed a systematic comparison of six publicly available transmission reconstruction models, evaluating their accuracy when predicting transmission events in simulated and real-world Mycobacterium tuberculosis outbreaks. We observed variability in the number of transmission links that were predicted with high probability (P ≥ 0.5) and low accuracy of these predictions against known transmission in simulated outbreaks. We also found a low proportion of epidemiologically supported case–contact pairs were identified in our real-world TB clusters. The specificity of all models was high, and a relatively high proportion of the total transmission events predicted by some models were true links, notably with TransPhylo, Outbreaker2, and Phybreak. Our findings may inform the choice of tools in TB transmission analyses and underscore the need for caution when interpreting transmission networks produced using probabilistic approaches.

During the 2003 rainy season, a follow-up survey in sentinel chickens was undertaken to assess the seasonal transmission of West Nile virus (WNV) in a sahelian ecosystem: the Ferlo (Senegal). The estimated incidence rate in chickens was 14% (95% CI 7–29), with a very low level of transmission between July and September, and a transmission peak occurring between September and October. Comparing these results with the estimate obtained from a previous transversal serological study performed on horses the same year in the same area, the relevance of sentinel chickens in estimating the WNV transmission rate is highlighted. Conventionally adult mosquito populations disappear during the dry season but WN disease was shown to be endemic in the study area. The mechanisms of virus maintenance are discussed.

Between July 1987 and June 1989, 1054 urinary isolates of enterobacteria from Kaohsiung, Taiwan were studied for their trimethoprim resistance. Trimethoprim resistance was defined as MIC greater than 4 μg/ml and high-level resistance by MIC greater than 1000 μg/ml. The incidence of trimethoprim resistance increased from 33·6% in 1987 to 42·1% in 1989. Among the resistant strains studied, 90% were resistant to high levels of trimethoprim. An increase in the proportion of resistant strains (33·9–46·3%) exhibiting high-level non-transferable trimethoprim resistance was noted. The distribution of the dihydrofolate reductase (DHFR) genes by colony hybridization in 374 trimethoprim-resistant isolates revealed the presence of type I and type V DHFR genes in most of these isolates (45·4% and 10·4% respectively). Type I was predominant in Escherichia coli whereas type V was frequently seen in Enterobacter spp. None showed homology with the type II and type III DHFR probe DNA. In addition, transposon Tn7 was present in 7·8% of 374 trimethoprim-resistant enterobacteria.

The purpose of the present study was to reconstruct the phylogeny of dengue virus serotype 4 (DENV-4) that was circulating in Espírito Santo state, Brazil, in 2013 and 2014, and to discuss the epidemiological implications associated with this evolutionary hypothesis. Partial envelope gene of eight DENV-4 samples from Espírito Santo state were sequenced and aligned with 72 worldwide DENV-4 reference sequences from GenBank. A phylogenetic tree was reconstructed through Bayesian Inference and the Time of the Most Recent Common Ancestor was estimated. The study detected the circulation of DENV-4 genotype II in Espírito Santo state, which was closely related to strains from the states of Mato Grosso collected in 2012 and of São Paulo sampled in 2015. This cluster emerged around 2011, approximately 4 years after the entry of the genotype II in Brazil through its northern states, possibly imported from Venezuela and Colombia. This is so far the first phylogenetic study of the DENV-4 circulating in Espírito Santo state and shows the importance of an internal route of dengue viral circulation in Brazil to the introduction of the virus into this state.

During the last year further investigations of germicidal mists, especially those produced by heat-volatilization of phenols, have been carried out. We are primarily interested in continuous disinfection of the air in the presence of man, and all our original experimental results appeared to show that a small quantity of the higher phenols in the mist form was more potent to bacteria than when in the vapour form. Thus, persistence as a mist long enough to ensure a duration of lethal effectiveness covering the time taken for at least one air turn-over was considered to be a desirable characteristic of a germicide to be used for our purpose.

Variation amongst Achromobacter-like strains was examined by DNA restriction endonuclease digestion and rDNA gene patterns generated using a non-radioactive probe. Chromosomal DNA was extracted from 12 cultures representing Achromobacter groups B, E and F, all from human blood cultures. DNA fingerprinting using EcoRI, HaeIII or HindIII sub-divided the strains in a similar manner to that obtained by their protein patterns. The HaeIII patterns, with their small number of bands, were the easiest to interpret. The EcoRI patterns included a species-specific triplet of bands but minor band patterns allowed further differentiation. The Achromobacter group F strains comprised a separate taxon and were distinct from the group B and E strains by all techniques examined. The study demonstrates that, in addition to total DNA digest analysis, rDNA gene restriction patterns provide a simple but discriminatory electrophoretic method for distinguishing within Achromobacter groups B and E.

The present inquiry was undertaken to obtain some indication of the relative frequencies of deaths amongst infants from the various forms of diarrhoea and enteritis—‘neonatal’, ‘parenteral’ and ‘infectious’—in the Greater London area in the decade before the war. Since much of the material needed for such an analysis was not available in the published records, a sampling inquiry, making use of the more elaborate records maintained by the Medical Officer of Health, was undertaken for the Borough of Willesden. A comparison of the relevant epidemiological and social conditions in this borough with those in the Greater London area as a whole showed, that for such a purpose, it might properly be regarded as a representative sample.

There was little evidence for the occurrence of the neonatal form in Willesden during the period studied, nor did the seasonal distribution of the deaths suggest that many took place in consequence of preceding parenteral infections. On the other hand, there did seem to be some evidence that a significant proportion of these deaths were in some degree associated with one another, in time or place or both, and it is suggested that this distribution might have resulted from the widespread dissemination in the community of one or more strains of some common micro-organism of relatively low virulence for all but the infant population.

A less detailed study of data for other London boroughs, viz., Bermondsey, Croydon, East Ham, Tottenham and West Ham, supported the main conclusion reached from the Willesden records.

Antimicrobial resistance (AMR) in pig populations is a public health concern. There is a lack of information of spatial distributions of AMR genes in pig populations at large scales. The objective of the study was to describe the spatial pattern of AMR genes in faecal samples from pig farms and to test if the AMR genes were spatially randomly distributed with respect to the geographic distribution of the pig farm population at risk. Faecal samples from 687 Danish pig farms were collected in February and March 2015. DNA was extracted and the levels of seven AMR genes (ermB, ermF, sulI, sulII, tet(M), tet(O) and tet(W)) were quantified on a high-throughput real-time PCR array. Spatial differences for the levels of the AMR genes measured as relative quantities were evaluated by spatial cluster analysis and creating of risk maps using kriging analysis and kernel density estimation. Significant spatial clusters were identified for ermB, ermF, sulII and tet(W). The broad spatial trends in AMR resistance evident in the risk maps were in agreement with the results of the cluster analysis. However, they also showed that there were only small scale spatial differences in the gene levels. We conclude that the geographical location of a pig farm is not a major determinant of the presence or high levels of AMR genes assessed in this study.

C. botulinum types A and B toxins required larger amounts of antitoxin for neutralization when fractions of the test dose of toxin were used than would be expected.

The degree of this dilution effect, i.e. the dilution ratio, varied with different sera. The dilution ratios with type A sera could be improved by allowing a greater time for combination to occur, or by mixing toxin and antitoxin in high concentration and diluting these mixtures.

The dilution ratios of type A sera from horses rose as immunization proceeded, the greatest rise occurring during the 3-month rest period following three small doses of toxoid.

A type A serum could be separated into fractions of different dilution ratio by precipitation with increasing concentrations of ammonium sulphate.

Type A antitoxins prepared by immunization of groups of guinea-pigs with two doses of toxoid, had dilution ratios far lower than those found in hyperimmune horse sera.

The dilution ratios of sera were lower when tested against a toxic toxin than against a more toxoided one.

A number of type A sera were tested at one level of test against a number of test toxins. There was no evidence of heterogeneity of the toxins and antitoxins tested.

The serum ratios were found to be correlated with the dilution ratios except where the serum ratios exceeded 0·64. Flocculation time was slow and varied from 6 to 48 hr. with different sera tested against the same toxoid.

I am greatly indebted to Miss M. Barr for her constant advice and encouragement in the execution of this work and in the preparation of this paper. I am grateful to Dr M. Sterne for the supply of C. botulinum type A and B toxins and for the benefit of his experience of animal botulism.

The emergence of type 6B Streptococcus pneumoniae resistant to five antibiotics (penicillin, chloramphenicol, trimethoprim–sulphamethoxazole, erythromycin and tetracycline) in both the Northern Territory and Queensland prompted an investigation of the genetic relatedness and patterns of migration of the isolates. Pulsed field gel electrophoresis of genomic DNA of 74 multiple drug-resistant (MDR) isolates cultured in both regions between August 1988 and June 1997 showed that 100% of MDR isolates from the Northern Territory and 96% of MDR strains from Queensland were genetically indistinguishable or closely related to the index strain. None of a further 65 type 6B isolates that were resistant to one or two, or susceptible to all of the above antibiotics, were clonally related to the MDR pneumococci. The geographical distribution of the MDR type 6B clone increased over time. The index strain, first isolated in Darwin in August 1988, was identified in Brisbane, 2900km distant, less than 4 years later and subsequently in other Queensland centres. Surveillance programmes are important to monitor the emergence and spread of potentially invasive MDR pneumococcal clones in countries that are well serviced by air and road transport.

Arctic rabies virus variant (ARVV) is enzootic in Quebec (Canada) north of the 55th parallel. With climate change, increased risk of re-incursion of ARVV in more densely populated southern regions raises public and animal health concerns. The objective of this study was to prioritise geographical areas to target for an early detection of ARVV incursion south of the 55th parallel based on the historical spatio-temporal trends of reported rabies in foxes in Quebec. Descriptive analyses of fox rabies cases from 1953 to 2017 were conducted. Three periods show increases in the number of fox rabies cases in southern regions and indicate incursion from northern areas or neighbouring provinces. The available data, particularly in central and northern regions of the province, were scarce and of low spatial resolution, making it impossible to identify the path of spread with precision. Hence, we investigated the use of multiple criteria, such as historical rabies cases, human population density and red fox (Vulpes vulpes) relative abundance, to prioritise areas for enhanced surveillance. This study underscores the need to define and maintain new criteria for selecting samples to be analysed in order to detect rapidly ARVV cases outside the current enzootic area and any potential re-incursion of the virus into central and southern regions of the province.

The virus of Aujeszky's disease (pseudo-rabies) has been found to have a particle size of 100—150 mμ. Two strains were employed in these experiments, one that of Aujeszky, and the other Shope's “mad-itch” strain. The results with both strains were identical.

This study aimed to estimate the disease burden of hepatitis E in a rural region in China. A total of 489 hepatitis E cases were reported according to a community-based survey in an active hepatitis surveillance system between 2008 and 2015, the questionnaire and record-review methods were constructed to evaluate the economic and health burden of hepatitis E virus infections from societal perspectives. All costs were converted to US$ in 2015. The age-standardized cumulative incidence rate was 107·9/100 000, and the median age-standardized annual incidence rate was 16·5/100 000. The median direct, indirect, and intangible cost were $1046·0, $49·1, and $77·3/patient, respectively, and the median economic burden per patient was $1836·5, which accounted for 51·2% of per capita disposable income. Moreover, the median quality-adjusted life year and visual analogue scale score were 0·7 and 70·0/case, respectively. Both economic burden and health burden of inpatients was more serious than that of outpatients (P < 0·001). Disease burden of hepatitis E is heavy on patients, their families, and society. More studies on the disease burden of hepatitis E are necessary to increase social awareness of the disease and confirm reasonable disease-control measures.

The introduction of preventive inoculation against typhoid and paratyphoid, and in particular its widespread application during the Great War, caused considerable difficulty in the interpretation of the Widal test. It was often impossible to decide whether the agglutinins demonstrated were due to active infection or to previous inoculation.