Following an extensive contact tracing exercise at a school in a London borough with one of highest tuberculosis (TB) rates in England, we estimated the background prevalence of latent TB infection to be significantly less than the widely accepted 10%. We screened 271 pupils aged 14–15 years in two groups: 96 pupils in group 1 had significant exposure (>8 h/week in the same room) to a case of infectious TB and 175 in group 2 who had minimal exposure. In group 1, 26% were diagnosed with latent or active TB, compared to 6.3% in group 2. Risk factors for TB infection (e.g. previous exposure or link to high-prevalence communities) were analysed using a cohort study design. In the univariable analysis only being in contact group 1 was statistically significantly associated with being a case (OR 5.25, 95%, P < 0.001). In the multivariable model contact group 1 remained significantly associated with being a case (adjusted OR 4.40, P = 0.001). We concluded that the 6.3% yield of TB infection in contact group 2 is either similar to or higher than the background prevalence rate of latent TB infection (LTBI) in this high TB prevalence London borough. Other parts of England with lower TB prevalence are likely to have even lower LTBI rates.

UK guidelines recommend routine HIV testing in high prevalence emergency departments (ED) and targeted testing for HBV and HCV. The ‘Going Viral’ campaign implemented opt-out blood-borne virus (BBV) testing in adults in a high prevalence ED, to assess seroprevalence, uptake, linkage to care (LTC) rates and staff time taken to achieve LTC. Diagnosis status (new/known/unknown), current engagement in care, and severity of disease was established. LTC was defined as patient informed plus ⩾1 clinic visit. A total of 6211/24 981 ED attendees were tested (uptake 25%); 257 (4.1%) were BBV positive (15 co-infected), 84 (33%) required LTC. 100/147 (68%) HCV positives were viraemic; 44 (30%) required LTC (13 new, 16 disengaged). 26/54 (48%) HBV required LTC (seven new, 11 disengaged). 16/71 (23%) HIV required LTC (10 new, five disengaged). 26/84 (31%) patients requiring LTC had advanced disease (CD4 <350, APRI (AST-to-Platelet Ratio Index) >1, Fibroscan F3/F4 or liver cancer), including five with AIDS-defining conditions and three hepatocellular carcinomas. There were five BBV-related deaths. BBV prevalence was high (4.1%); most were HCV (2.4%). HIV patients were more successfully and quickly LTC than HBV or HCV patients. ED testing was valuable as one-third of those requiring LTC (new, disengaged or unknown status patients) had advanced disease.

Evidence is emerging regarding the influence of meteorological factors on seasonal respiratory syncytial virus outbreaks. Data however, are limited for subtropical regions, especially in the southern hemisphere. We examined whether meteorological data (daily minimum and maximum temperatures, rainfall, relative humidity, dew point, daily global solar exposure) and tourist numbers were associated with the incidence of RSV in children aged <5 years for the Gold Coast region of South-East Queensland, Australia (latitude 28.0°S). RSV cases between 1 July 2007 and 30 June 2016 were identified from the Pathology Queensland Gold Coast Laboratory database. Time-series methods were used to identify seasonal patterns. RSV activity peaked in mid-to-late autumn (April–May), tapering in winter (June–August). While most meteorological variables measured were associated with RSV incidence, rainfall (ρ = 0.40, 95% confidence interval (CI) 0.32–0.48) and humidity (ρ = 0.38, 95% CI 0.29–0.46) 8 weeks earlier had the nearest temporal relationship. Tourist numbers were not correlated with RSV activity. Identifying meteorological conditions associated with seasonal RSV epidemics can improve understanding of virus transmission and assist planning for their impact upon the health sector, including timing of passive RSV immunoprophylaxis for high-risk infants and future public health interventions, such as maternal immunisation with RSV vaccines.

Pathogen burden is a construct developed to assess the cumulative effects of multiple, persistent pathogens on morbidity and mortality. Despite the likely biological wear and tear on multiple body systems caused by persistent infections, few studies have examined the impact of total pathogen burden on such outcomes and specifically on preclinical markers of dysfunction. Using data from two waves of the National Health and Nutrition Examination Survey, we compared three alternative methods for measuring pathogen burden, composed of mainly persistent viral infections, using a cumulative deficits index (CDI) as an outcome: single pathogen associations, a pathogen burden summary score and latent class analyses. We found significant heterogeneity in the distribution of the CDI by age, sex, race/ethnicity and education. There was an association between pathogen burden and the CDI by all three metrics. The latent class classification of pathogen burden showed particularly strong associations with the CDI; these associations remained after controlling for age, sex, body mass index, smoking, race/ethnicity and education. Our results suggest that pathogen burden may influence early clinical indicators of poor health as measured by the CDI. Our results are salient since we were able to detect these associations in a relatively young population. These findings suggest that reducing pathogen burden and the specific pathogens that drive the CDI may provide a target for preventing the early development of age-related physiological changes.

Shigellosis causes significant morbidity and mortality in developing and developed countries, mostly among infants and young children. The World Health Organization estimates that more than one million people die from Shigellosis every year. In order to evaluate trends in Shigellosis in Israel in the years 2002–2015, we analysed national notifiable disease reporting data. Shigella sonnei was the most commonly identified Shigella species in Israel. Hospitalisation rates due to Shigella flexenri were higher in comparison with other Shigella species. Shigella morbidity was higher among infants and young children (age 0–5 years old). Incidence of Shigella species differed among various ethnic groups, with significantly high rates of S. flexenri among Muslims, in comparison with Jews, Druze and Christians. In order to improve the current Shigellosis clinical diagnosis, we developed machine learning algorithms to predict the Shigella species and whether a patient will be hospitalised or not, based on available demographic and clinical data. The algorithms’ performances yielded an accuracy of 93.2% (Shigella species) and 94.9% (hospitalisation) and may consequently improve the diagnosis and treatment of the disease.

We report an ongoing measles outbreak in Greece. The first cases were notified through the mandatory notification system on May 2017 in Northern Greece and concerned a cluster of three imported cases in unvaccinated Roma siblings. So far, 3150 cases have been reported in all 13 Regions. Initially, the outbreak mainly affected Greek Roma but as it progressed it spread to non-minority Greek nationals. The outbreak reached its ultimate peak on week 10/2018 but from week 15/2018 has been gradually declining. Most cases (60.6%) were Roma (especially children <10 year-old) followed by non-minority Greek nationals (29.3%; mostly young adults). The majority (80.4%) were unvaccinated. Interestingly, 129 (4.1%) cases were healthcare workers (HCWs). Genotype B3 was identified by molecular methods in all 87 cases tested. Overall, 61.3% of the cases were hospitalised. Complications were reported in 17.1% of the cases among which four deaths. The outbreak occurred after 3 years without local endemic measles transmission. Extensive vaccination implemented as the major public health measure managed to prevent the emergence of a large number of cases in refugee/migrant hosting sites. Mitigation efforts currently focus on raising awareness among HCWs and closing the immunisation gap in populations with suboptimal vaccination coverage.

The hepatitis E virus (HEV) has been described in humans and various animal species in different regions of the world. However, the knowledge on natural HEV infection in non-human primates and the corresponding risk of zoonotic transmission is scarce. To determine whether primates in captivity are affected by HEV infection, we investigated 259 individual sera of clinically healthy non-human primates of 14 species from nine German zoos. Using a commercial double-antigen-sandwich ELISA and a commercial IgG ELISA, 10 animals (3·9%) reacted positive in at least one assay. Three ape species and one Old World monkey species were among the seropositive animals: bonobo (Pan paniscus), gorilla (Gorilla gorilla gorilla), lar gibbon (Hylobates lar) and drill (Mandrillus leucophaeus). Testing for anti-HEV-IgM antibodies by commercial ELISA and for viral RNA by reverse-transcription real-time polymerase chain reaction resulted in negative results for all animals indicating the absence of acute HEV infections. In the past, no clinical signs of hepatitis were recorded for the seropositive animals. The results suggest that non-human primates in zoos can get naturally and subclinically infected with HEV or related hepeviruses. Future studies should evaluate potential sources and transmission routes of these infections and their impact on human health.

According to the Centers for Disease Control and Prevention (CDC), from 2000 to 2014, reported cases of legionellosis per 100 000 population increased by 300% in the USA, although reports on disease seasonality are inconsistent. Using two national databases, we assessed seasonal patterns of legionellosis in the USA. We created a monthly time series from 1993 to 2015 of reported cases of legionellosis from the CDC, and from 1997 to 2006 of medical claims of legionellosis-related hospitalisation in older adults from the Centers for Medicaid and Medicare Services (CMS). We split the study time interval into two segments (before and after 2003), and applied a Poisson harmonic regression model to each dataset and each segment. The time series of monthly counts exhibited a significant shift of seasonal peaks from mid-September (9.676 ± 0.164 months) before 2003 to mid-August (8.452 ± 0.042 months) after 2003, along with an alarming increase in the amplitude of seasonal peaks in both CDC and CMS data. The lowest monthly reported cases of legionellosis in 2015 (281) exceed the maximum value reported before 2003 (206). We also observed a discrepancy between CDC and CMS data, suggesting that not all cases of legionellosis diagnosed by hospital-based laboratories were reported to the CDC. Improved reporting of legionellosis is required to better inform the public and organise disease prevention.

Reducing the risk of human immunodeficiency virus type 1 (HIV-1) transmission is still a public health priority. The development of effective control strategies relies on the quantification of the effects of prophylactic and therapeutic measures in disease incidence. Although several assays can be used to estimate HIV incidence, these estimates are limited by the poor performance of these assays in distinguishing recent from long-standing infections. To address such limitation, we have developed an assay to titrate p24-specific IgG3 antibodies as a marker of recent infection. The assay is based on a recombinant p24 protein capable to detect total IgG antibodies in sera using a liquid micro array and enzyme-linked immunosorbent assay. Subsequently, the assay was optimised to detect and titrate anti-p24 IgG3 responses in a panel of sequential specimens from seroconverters over 24 months. The kinetics of p24-specific IgG3 titres revealed a transient peak in the 4 to 5-month period after seroconversion. It was followed by a sharp decline, allowing infections with less than 6 months to be distinguished from older ones. The developed assay exhibited a mean duration of recent infection of 144 days and a false-recent rate of ca. 14%. Our findings show that HIV-1 p24-specific IgG3 titres can be used as a tool to evaluate HIV incidence in serosurveys and to monitor the efficacy of vaccines and other transmission control strategies.

Human papillomavirus (HPV) testing is used in the triage of women with a borderline smear result. The efficiency of testing women with a low-grade squamous intraepithelial lesion (LSIL) and atypical squamous cells of undetermined significance (ASCUS) is less clear. For this reason we used a new HPV test that detects E6/E7 messenger RNA (mRNA), which might have a higher specificity. The objective of this prospective study was to assess whether HPV E6/E7 mRNA positivity in women with ASCUS and LSIL at baseline, is able to predict those women who have a high risk of developing a histological cervical intraepithelial neoplasia (CIN2) or worse lesion. We took into consideration the women's age and HPV DNA genotype and followed them up for 3 years. Cervical samples from women with high-risk HPV (HR-HPV) DNA-positive ASCUS (n = 90) or LSIL (n = 222) were tested for the presence of HR-HPV E6/E7 mRNA and the women were monitored for the development of histopathologically verified CIN2+. Thirteen patients with ASCUS and 17 with LSIL did not complete follow-up. All patients with LSIL and ASCUS, enrolled in this study, had confirmed lesions at the colposcopic examination. Follow-up was available for 312 women, 193 were positive in the HR-HPV DNA test and 93 had a HPV E6/E7 mRNA positive test. Finally, 22 women positive in the HPV DNA test for high-risk genotypes and with positive E6/E7 mRNA had a histologically confirmed CIN2+. Only two cases with negative HPV E6/E7 mRNA had CIN2+. The study shows that women positive in the HPV E6/E7 mRNA test have a greater risk of malignant progression of cervical lesions and therefore deserve greater attention and earlier check-ups.

To understand increasing rates of hepatitis C virus (HCV) infection in Tennessee, we conducted testing, risk factor analysis and a nested case–control study among persons who use drugs. During June–October 2016, HCV testing with risk factor assessment was conducted in sexually transmitted disease clinics, family planning clinics and an addiction treatment facility in eastern Tennessee; data were analysed by using multivariable logistic regression. A nested case–control study was conducted to assess drug-using risks and behaviours among persons who reported intranasal or injection drug use (IDU). Of 4753 persons tested, 397 (8.4%) were HCV-antibody positive. HCV infection was significantly associated with a history of both intranasal and IDU (adjusted odds ratio (aOR) 35.4, 95% confidence interval (CI) 24.1–51.9), IDU alone (aOR 52.7, CI 25.3–109.9), intranasal drug use alone (aOR 2.6, CI 1.8–3.9) and incarceration (aOR 2.7, CI 2.0–3.8). By 4 October 2016, 574 persons with a reported history of drug use; 63 (11%) were interviewed further. Of 31 persons who used both intranasal and injection drugs, 26 (84%) reported previous intranasal drug use, occurring 1–18 years (median 5.5 years) before their first IDU. Our findings provide evidence that reported IDU, intranasal drug use and incarceration are independent indicators of risk for past or present HCV infection in the study population.

Gastric cancer is the third leading cause of cancer death worldwide. Gastric cancer screening using upper gastrointestinal series, endoscopy and serological testing has been performed in population-based (employee-based and community-based) and opportunistic cancer screening in Japan. There were 45 531 gastric cancer deaths in 2016, with the low screening and detection rates. Helicobacter pylori (H. pylori) screening followed by eradication treatment is recommended in high-risk population settings to reduce gastric cancer incidence. The aim of this study was to evaluate the cost-effectiveness of H. pylori screening followed by eradication treatment for a high-risk population in the occupational health setting. Decision trees and Markov models were developed for two strategies; H. pylori antibody test (HPA) screening and no screening. Targeted populations were hypothetical cohorts of employees aged 20, 30, 40, 50 and 60 years using a company health payer perspective on a lifetime horizon. Per-person costs and effectiveness (quality-adjusted life-years) were calculated and compared. HPA screening yielded greater benefits at the lower cost than no screening. One-way and probabilistic sensitivity analyses using Monte-Carlo simulation showed strong robustness of the results. H. pylori screening followed by eradication treatment is recommended to prevent gastric cancer for employees in Japan, on the basis of cost-effectiveness.

Knowledge, attitudes and practices (KAP) of the population regarding severe fever with thrombocytopenia syndrome (SFTS) in endemic areas of Lu'an in China were assessed before and after an intervention programme. The pre-intervention phase was conducted using a sample of 425 participants from the 12 selected villages with the highest rates of endemic SFTS infection. A predesigned interview questionnaire was used to assess KAP. Subsequently, an intervention programme was designed and applied in the selected villages. KAP was re-assessed for each population in the selected villages using the same interview questionnaire. Following 2 months of the programme, 339 participants had completed the re-assessed survey. The impact of the intervention programme was evaluated using suitable statistical methods. A significant increase in the KAP and total KAP scores was noted following the intervention programme, whereas the proportion of correct knowledge, the positive attitudes and the effective practices toward SFTS of respondents increased significantly. The intervention programme was effective in improving KAP level of SFTS in populations that were resident in endemic areas.

Acute rheumatic fever (ARF) continues to produce a significant burden of disease in New Zealand (NZ) Māori and Pacific peoples. Serious limitations in national surveillance data mean that accurate case totals cannot be generated. Given the changing epidemiology of ARF in NZ and the major national rheumatic fever prevention programme (2012–2017), we updated our previous likely true case number estimates using capture–recapture analyses. Aims were to estimate the likely true incidence of ARF in NZ and comment on the changing ability to detect cases. Data were obtained from national hospitalisation and notification databases. The Chapman Estimate partially adjusted for bias. An estimated 2342 likely true new cases arose from 1997 to 2015, giving a mean annual incidence of 2·9 per 100 000 (95% CI 2·5–3·5). Compared with the pre-intervention (2009–2011) baseline incidence (3·4 per 100 000, 95% CI 2·9–4·0), the likely true 2015 incidence declined 44%. Large gaps in data completeness are slowly closing. During the period 2012–2015, 723 cases were identified; 83·8% of notifications were matched to hospitalisation data, and 87·2% of hospitalisations matched to notifications. Despite this improvement, clinicians need to remain aware of the need to notify atypical patients. A possible unintended consequence of the national ARF prevention programme is increased misdiagnosis.

Measles is a target for elimination in all six WHO regions by 2020, and over the last decade, there has been considerable progress towards this goal. Surveillance is recognised as a cornerstone of elimination programmes, allowing early identification of outbreaks, thus enabling control and preventing re-emergence. Fever–rash surveillance is increasingly available across WHO regions, and this symptom-based reporting is broadly used for measles surveillance. However, as measles control increases, symptom-based cases are increasingly likely to reflect infection with other diseases with similar symptoms such as rubella, which affects the same populations, and can have a similar seasonality. The WHO recommends that cases from suspected measles outbreaks be laboratory-confirmed, to identify ‘true’ cases, corresponding to measles IgM titres exceeding a threshold indicative of infection. Although serological testing for IgM has been integrated into the fever–rash surveillance systems in many countries, the logistics of sending in every suspected case are often beyond the health system's capacity. We show how age data from serologically confirmed cases can be leveraged to infer the status of non-tested samples, thus strengthening the information we can extract from symptom-based surveillance. Applying an age-specific confirmation model to data from three countries with divergent epidemiology across Africa, we identify the proportion of cases that need to be serologically tested to achieve target levels of accuracy in estimated infected numbers and discuss how this varies depending on the epidemiological context. Our analysis provides an approach to refining estimates of incidence leveraging all available data, which has the potential to improve allocation of resources, and thus contribute to rapid and efficient control of outbreaks.

Although measles incidence has reached historic lows in many parts of the world, the disease still causes substantial morbidity globally. Even where control programs have succeeded in driving measles locally extinct, unless vaccination coverage is maintained at extremely high levels, susceptible numbers may increase sufficiently to spark large outbreaks. Human mobility will drive potentially infectious contacts and interact with the landscape of susceptibility to determine the pattern of measles outbreaks. These interactions have proved difficult to characterise empirically. We explore the degree to which new sources of data combined with existing public health data can be used to evaluate the landscape of immunity and the role of spatial movement for measles introductions by retrospectively evaluating our ability to predict measles outbreaks in vaccinated populations. Using inferred spatial patterns of accumulation of susceptible individuals and travel data, we predicted the timing of epidemics in each district of Pakistan during a large measles outbreak in 2012–2013 with over 30 000 reported cases. We combined these data with mobility data extracted from over 40 million mobile phone subscribers during the same time frame in the country to quantify the role of connectivity in the spread of measles. We investigate how different approaches could contribute to targeting vaccination efforts to reach districts before outbreaks started. While some prediction was possible, accuracy was low and we discuss key uncertainties linked to existing data streams that impede such inference and detail what data might be necessary to robustly infer timing of epidemics.

Given the growing use of electric bidet toilets in Japan and other countries, we assessed the relationship between bidet toilet use and haemorrhoids or urogenital infections. Data were collected using a web-based longitudinal survey. In total, 10 305 subjects randomly selected from panels of a Japanese website research company for the baseline survey in 2013 were asked about their frequency of bidet toilet use and receipt of a doctor's diagnosis or subjective symptom of haemorrhoids and urogenital infections. One- and three-year follow-up surveys were performed in 2014 and 2016, respectively, and information on newly diagnosed/experienced outcomes occurring during the follow-up period were collected. Cumulative incidence of haemorrhoids and urogenital infections was not significantly increased by habitual use of a bidet toilet. In men, more habitual users reported subjective symptoms of irritated skin around the anus, which were newly experienced during follow-up than non-habitual users (adjusted risk ratio 1.36 (95% confidence interval 1.06–1.75)). Further studies are needed to confirm this relationship. Several of the outcomes were significantly more prevalent in habitual users, but these results were probably explained by reverse causation.

Respondent-driven sampling (RDS) is widely used to estimate HIV prevalence in men who have sex with men (MSM). Mathematical models that are calibrated to these data may be compromised if they fail to account for selection biases in RDS surveys. To quantify the potential extent of this bias, an agent-based model of HIV in South Africa was calibrated to HIV prevalence and sexual behaviour data from South African studies of MSM, first reweighting the modelled MSM population to match the younger age profile of the RDS surveys (age-adjusted analysis) and then without reweighting (unadjusted analysis). The model estimated a median HIV prevalence in South African MSM in 2015 of 34.6% (inter-quartile range (IQR): 31.4–37.2%) in the age-adjusted analysis, compared with 26.1% (IQR: 24.1–28.4%) in the unadjusted analysis. The median lifetime risk of acquiring HIV in exclusively homosexual men was 88% (IQR: 82–92%) in the age-adjusted analysis, compared with 76% (IQR: 64–85%) in the unadjusted analysis. These results suggest that RDS studies may under-estimate the exceptionally high HIV prevalence rates in South African MSM because of over-sampling of younger MSM. Mathematical models that are calibrated to these data need to control for likely over-sampling of younger MSM.

Vaccination remains a mainstay of companion animal population health. However, how vaccine use at a population level complies with existing guidelines is unknown. Here we use electronic health records to describe vaccination in dogs, cats and rabbits attending a large sentinel network of UK veterinary practices. In total, 77.9% (95% CI: 77.6–78.1) of animals had recorded vaccinations. The percentage of animals with recorded vaccinations was higher in dogs, neutered animals, in insured dogs and cats and in purebred dogs. Vaccination rates varied in different regions of Great Britain in all species. Dogs and cats belonging to owners living in less deprived areas of England and Scotland were more likely to be recorded as vaccinated. In the vaccinated population, cats received more core vaccines per year of life (0.86) than dogs (0.75), with feline leukaemia vaccines almost as frequent as core vaccines. In dogs, leptospira vaccines were more frequent than core vaccines. This descriptive study suggests a substantial proportion of animals are not benefiting from vaccine protection. For the first time, we identify potential factors associated with variations in recorded vaccination frequency, providing a critical baseline against which to monitor future changes in companion animal vaccination and evidence to inform future targeted health interventions.

Since April 2014 all presumptive Salmonella isolates received by Public Health England (PHE) have been characterised using whole genome sequencing (WGS) and the genomic data generated used to identify clusters of infection. To inform the implementation and development of a national gastrointestinal infection surveillance system based on WGS we have retrospectively identified genetically related clusters of Salmonella Enteritidis and Salmonella Typhimurium infection over a one year period and determined the distribution of these clusters by PHE operational levels. Using a constrained WGS cluster definition based on single nucleotide polymorphism distance, case frequency and temporal spread we demonstrate that the majority of clusters spread to multiple PHE operational levels. The greatest investigative burden is on national level staff investigating small, geographically dispersed clusters. We also demonstrate that WGS identifies long-running, slowly developing clusters that may previously have remained undetected. This analysis also indicates likely increased workload for local health protection teams and will require an operational strategy to balance limited human resources with the public health importance of investigating small, geographically contained clusters of highly related cases. While there are operational challenges to its implementation, integrated cluster detection based on WGS from local to international level will provide further improvements in the identification of, response to and control of clusters of Salmonella spp. with public health significance.