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Background Tuberculosis (TB) remains a public health problem in the UK-born population of England, including among young adults. Ecological studies indicate that deprivation is an important risk factor for TB, but there are few recent individual-level studies in high income countries that have investigated the association between poverty-related social determinants of health inequality (SDH) and TB. Our objective was to measure the association between individual socio-economic status and social determinants of health, and TB, taking into account the clustering of social risk factors in individuals, and to estimate the potential population impact on TB rates. Methods Secondary analyses of a nationwide case-control study conducted among UK-born White adults aged 23 to 38 years at diagnosis of their first TB episode, and randomly selected age and sex frequency-matched community controls. Data on some SDH (education, household overcrowding, tobacco smoking, alcohol use, drugs use, and history of homelessness and prison) were collected in face-to-face interviews. Statistical analyses, using logistic regression models, was informed by a theoretical causal framework (Directed Acyclic Graph) of plausible inter-relationships between the measured social factors. Results Overall, 681 TB cases and 1183 controls were recruited. The risk of TB was about four times higher in subjects whose formal education was up to GCSE O-levels or less compared to those with at least a university degree (OR=3.94; 95%CI: 2.74; 5.67), after controlling for other TB risk factors (age, sex, BCG vaccination and stays in Africa or Asia for 33 months). After simultaneously adjusting for these risk factors and all measured social determinants, higher TB risk was also independently associated with tobacco smoking, use of drugs (especially injectable drugs - OR=5.67; 95%CI: 2.68; 11.98), history of homelessness and deprivation in the area of residence. Population Attributable Fraction (PAF) estimates suggested that tobacco use and class-A drug use were, respectively, responsible for 18% and 15% of TB cases in the target population. Conclusion The results provide insight into some of the mechanisms through which deprivation increases the risk of TB in the general population in England and support the argument for improved approaches to TB control efforts, such as integrated health and social services in high-risk young adult populations.

Background The roll-out of anti-retroviral therapy (ART) has changed contexts of human immunodeficiency virus (HIV) risk. Here, we summarise direct estimates of HIV incidence among adolescent girls and young women (AGYW) since ART and before large investments in targeted prevention for AGYW in sub-Saharan Africa. Methods Database searches identified studies reporting HIV incident data from serological samples collected among 15-24 year-old females in 10 countries selected for PEPFAR investment in 2015. Estimates collected between 2005-2015, published or received from authors, were summarised by age and sex, and pooled by region. Findings Fifty-one analyses were identified from nine of the eligible countries (save Lesotho). Directly-observed incidence rates were lowest among AGYW in Kumi, Uganda (0.38%) and highest in KwaZulu-Natal, South Africa (7.8% among 15-19y; 8.6% in 20-24y); fishing communities in Uganda (12.4% and 4.7% among 15-19y and 20-24y females); and among sex workers aged 18-24y in South Africa (13.2%) and Zimbabwe (10.8%). In pooled rates from general population studies, the greatest sex differentials were in the youngest age groups, i.e., 15-19y females compared to males in both Southern African (relative risk=5.94; 95% CI:3.39-10.44) and Eastern African countries (3.22; 95% CI:1.51-6.87), and not significantly different among the oldest (25-29y) in either region. Incidence often peaked earlier (during teenage years) among high-risk compared to general populations. Since 2005, AGYW incidence declined in Rakai (Uganda), Manicaland (Zimbabwe), and among sex workers in Kenya, but not in the highest-risk communities in South Africa. Interpretation Few sources of direct estimates of HIV incidence exist in high-burden countries and trend analyses with age/sex disaggregated data are rare but indicate recent declines among AGYW. In some of the highest-risk settings, however, little evidence exists to suggest ART availability and other efforts slowed transmission by 2016. Despite wide geographic diversity in absolute levels of AGYW incidence, risk relative to males persisted in all settings, with the greatest sex differentials in the youngest age groups. To end new infections among the growing population of adolescents in sub-Saharan Africa, prevention programs must address gender inequalities driving excessive risk among adolescent girls.

Background Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Methods Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. Results The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Conclusions Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

BackgroundEvidence of protection from childhood BCG against tuberculosis (TB) in adulthood, when most transmission occurs, is important for TB control and resource allocation.MethodsWe conducted a population-based case-control study of protection by BCG given to children aged 12 to 13 years against tuberculosis occurring 10 to 29 years later. We recruited UK-born white subjects with tuberculosis and randomly sampled white community controls. Hazard ratios and 95% confidence intervals were estimated using case-cohort Cox regression, adjusting for potential confounding factors, including socio-economic status, smoking, drug use, prison and homelessness. Vaccine effectiveness (VE=1-hazard ratio) was assessed at successive intervals more than 10 years following vaccinationResultsWe obtained 677 cases and 1170 controls after a 65% response rate in both groups. Confounding by deprivation, education and lifestyle factors was slight 10-20 years after vaccination, more evident after 20 years. VE 10 -15 years after vaccination was 51% (95% CI 21, 69%) and 57% (CI 33, 72%) at 15-20 years. Subsequently BCG protection appeared to wane; 20-25 years VE=25% (CI -14%, 51%) and 25-29 years VE= 1% (CI -84%, 47%). Based on multiple imputation of missing data (in 17% subjects) VE estimated in the same intervals after vaccination were similar (56% (CI 33, 72%), 57% (CI 36, 71%), 25% (-10, 48%), 21% (-39, 55%).ConclusionsSchool-age BCG vaccination offered moderate protection against tuberculosis for at least 20 years which is longer than previously thought. This has implications for assessing the costeffectiveness of BCG vaccination and when evaluating new TB vaccines.

Time series regression has been developed and long used to evaluate the short-term associations of air pollution and weather with mortality or morbidity of non-infectious diseases. The application of the regression approaches from this tradition to infectious diseases, however, is less well explored and raises some new issues.We discuss and present potential solutions for five issues often arising in such analyses: changes in immune population, strong autocorrelations, a wide range of plausible lag structures and association patterns, seasonality adjustments, and large overdispersion.The potential approaches are illustrated with datasets of cholera cases and rainfall from Bangladesh and influenza and temperature in Tokyo. Though this article focuses on the application of the traditional time series regression to infectious diseases and weather factors, we also briefly introduce alternative approaches, including mathematical modeling, wavelet analysis, and autoregressive integrated moving average (ARIMA) models.Modifications proposed to standard time series regression practice include using sums of past cases as proxies for the immune population, and using the logarithm of lagged disease counts to control autocorrelation due to true contagion, both of which are motivated from "susceptible-infectious-recovered" (SIR) models. The complexity of lag structures and association patterns can often be informed by biological mechanisms and explored by using distributed lag non-linear models. For overdispersed models, alternative distribution models such as quasi-Poisson and negative binomial should be considered. Time series regression can be used to investigate dependence of infectious diseases on weather, but may need modifying to allow for features specific to this context., Environmental Research, 142, pp.319-327; 2015

In 2017, WHO convened a working group of global experts to develop the Preferred Product Characteristics (PPC) for Next-Generation Influenza Vaccines. PPCs are intended to encourage innovation in vaccine development. They describe WHO preferences for parameters of vaccines, in particular their indications, target groups, implementation strategies, and clinical data needed for assessment of safety and efficacy. PPCs are shaped by the global unmet public health need in a priority disease area for which WHO encourages vaccine development. These preferences reflect WHO's mandate to promote the development of vaccines with high public health impact and suitability in Low- and Middle-Income Countries (LMIC). The target audience is all entities intending to develop or to achieve widespread adoption of a specific influenza vaccine product in these settings. The working group determined that existing influenza vaccines are not well suited for LMIC use. While many developed country manufactures and research funders prioritize influenza vaccine products for use in adults and the elderly, most LMICs do not have sufficiently strong health systems to deliver vaccines to these groups. Policy makers from LMICs are expected to place higher value on vaccines indicated for prevention of severe illness, however the clinical development of influenza vaccines focuses on demonstrating prevention of any influenza illness. Many influenza vaccine products do not meet WHO standards for programmatic suitability of vaccines, which introduces challenges when vaccines are used in low-resource settings. And finally, current vaccines do not integrate well with routine immunization programs in LMICs, given age of vaccine licensure, arbitrary expiration dates timed for temperate country markets, and the need for year-round immunization in countries with prolonged influenza seasonality. While all interested parties should refer to the full PPC document for details, in this article we highlight data needs for new influenza vaccines to better demonstrate the value proposition in LMICs.

BackgroundUntil recently, evidence that protection from the bacillus Calmette–Guérin (BCG) vaccination lasted beyond 10 years was limited. In the past few years, studies in Brazil and the USA (in Native Americans) have suggested that protection from BCG vaccination against tuberculosis (TB) in childhood can last for several decades. The UK’s universal school-age BCG vaccination programme was stopped in 2005 and the programme of selective vaccination of high-risk (usually ethnic minority) infants was enhanced.ObjectivesTo assess the duration of protection of infant and school-age BCG vaccination against TB in the UK.MethodsTwo case–control studies of the duration of protection of BCG vaccination were conducted, the first on minority ethnic groups who were eligible for infant BCG vaccination 0–19 years earlier and the second on white subjects eligible for school-age BCG vaccination 10–29 years earlier. TB cases were selected from notifications to the UK national Enhanced Tuberculosis Surveillance system from 2003 to 2012. Population-based control subjects, frequency matched for age, were recruited. BCG vaccination status was established from BCG records, scar reading and BCG history. Information on potential confounders was collected using computer-assisted interviews. Vaccine effectiveness was estimated as a function of time since vaccination, using a case–cohort analysis based on Cox regression.ResultsIn the infant BCG study, vaccination status was determined using vaccination records as recall was poor and concordance between records and scar reading was limited. A protective effect was seen up to 10 years following infant vaccination [p = 0.396). The analyses of the protective effect of infant BCG vaccination were adjusted for confounders, including birth cohort and ethnicity. For school-aged BCG vaccination, VE was 51% (95% CI 21% to 69%) 10–15 years after vaccination and 57% (95% CI 33% to 72%) 15–20 years after vaccination, beyond which time protection appeared to wane. Ascertainment of vaccination status was based on self-reported history and scar reading.LimitationsThe difficulty in examining vaccination sites in older women in the high-risk minority ethnic study population and the sparsity of vaccine record data in the later time periods precluded robust assessment of protection from infant BCG vaccination > 10 years after vaccination.ConclusionsInfant BCG vaccination in a population at high risk for TB was shown to provide protection for at least 10 years, whereas in the white population school-age vaccination was shown to provide protection for at least 20 years. This evidence may inform TB vaccination programmes (e.g. the timing of administration of improved TB vaccines, if they become available) and cost-effectiveness studies. Methods to deal with missing record data in the infant study could be explored, including the use of scar reading.FundingThe National Institute for Health Research Health Technology Assessment programme. During the conduct of the study, Jonathan Sterne, Ibrahim Abubakar and Laura C Rodrigues received other funding from NIHR; Ibrahim Abubakar and Laura C Rodrigues have also received funding from the Medical Research Council. Punam Mangtani received funding from the Biotechnology and Biological Sciences Research Council.

Almost all human infections by avian influenza viruses (AIVs) are transmitted from poultry. A systematic review was conducted to identify practices associated with human infections, their prevalence, and rationale. Observational studies were identified through database searches. Meta-analysis produced combined odds ratio estimates. The prevalence of practices and rationales for their adoptions were reported. Of the 48,217 records initially identified, 65 articles were included. Direct and indirect exposures to poultry were associated with infection for all investigated viral subtypes and settings. For the most frequently reported practices, association with infection seemed stronger in markets than households, for sick and dead than healthy poultry, and for H7N9 than H5N1. Practices were often described in general terms and their frequency and intensity of contact were not provided. The prevalence of practices was highly variable across studies, and no studies comprehensively explored reasons behind the adoption of practices. Combining epidemiological and targeted anthropological studies would increase the spectrum and detail of practices that could be investigated and should aim to provide insights into the rationale(s) for their existence. A better understanding of these rationales may help to design more realistic and acceptable preventive public health measures and messages.

Conjugate vaccines against Haemophilus influenzae type b (Hib) are widely used. The full implications of Hib vaccination schedule for vaccine effectiveness (VE) are unclear.We searched the literature for observational studies reporting the effectiveness of conjugate Hib vaccines administered according to different schedules. We summarized dose-specific VE estimates, where appropriate, using random effects meta-analysis.Thirty-one eligible articles (reporting 30 studies conducted in 17 countries) were identified. Meta-analysis of case-control studies using community controls produced VE estimates against Hib meningitis of 55% (95% confidence interval: 2-80%, based on 3 studies), 96% (86-99%, 3 studies) and 96% (86-99%, 4 studies) after 1, 2 and 3 doses of vaccines other than the polyribosyl ribitol phosphate outer membrane protein vaccine. Estimates were similar using hospital controls. VE against invasive Hib disease in case-control studies was estimated as 59% (30-76%, 3 studies) and 97% (87-99%, 3 studies) for 1 and 3 doses (insufficient data were identified to estimate 2-dose VE). Point estimates from 2 studies suggested VE90% after 1 dose of the polyribosyl ribitol phosphate outer membrane protein vaccine, but meta-analysis was not possible. Using data from 4 cohort studies, 3-dose VE was estimated as 94% (88-97%). There was some evidence that Hib vaccine was less effective when administered with acellular (rather than whole cell) pertussis vaccine. Weak evidence from 2 studies suggested that a booster confers some additional protection following full primary vaccination and may compensate for an incomplete primary series.Observational data suggest that ≥2 doses of Hib vaccine are required for high effectiveness, but do not strongly favor any particular schedule.

Highly pathogenic avian influenza virus subtype H5N1 is endemic in Asia, with live bird trade as a major disease transmission pathway. A cross-sectional survey was undertaken in northern Vietnam to investigate the structure of the live bird market (LBM) contact network and the implications for virus spread. Based on the movements of traders between LBMs, weighted and directed networks were constructed and used for social network analysis and individual-based modeling. Most LBMs were connected to one another, suggesting that the LBM network may support large-scale disease spread. Because of cross-border trade, it also may promote transboundary virus circulation. However, opportunities for disease control do exist. The implementation of thorough, daily disinfection of the market environment as well as of traders’ vehicles and equipment in only a small number of hubs can disconnect the network dramatically, preventing disease spread. These targeted interventions would be an effective alternative to the current policy of a complete ban of LBMs in some areas. Some LBMs that have been banned still are very active, and they likely have a substantial impact on disease dynamics, exhibiting the highest levels of susceptibility and infectiousness. The number of trader visits to markets, information that can be collected quickly and easily, may be used to identify LBMs suitable for implementing interventions. This would not require prior knowledge of the force of infection, for which laboratory-confirmed surveillance would be necessary. These findings are of particular relevance for policy development in resource-scarce settings.

School closure is often considered as an influenza control measure, but its effects on transmission are poorly understood. We used 2 approaches to estimate how school holidays affect the contact parameter (the per capita rate of contact sufficient for infection transmission) for influenza using primary care data from England and Wales (1967–2000). Firstly, we fitted an age-structured susceptible-infectious-recovered model to each year's data to estimate the proportional change in the contact parameter during school holidays as compared with termtime. Secondly, we calculated the percentage difference in the contact parameter between holidays and termtime from weekly values of the contact parameter, estimated directly from simple mass-action models. Estimates were combined using random-effects meta-analysis, where appropriate. From fitting to the data, the difference in the contact parameter among children aged 5–14 years during holidays as compared with termtime ranged from a 36% reduction to a 17% increase; estimates were too heterogeneous for meta-analysis. Based on the simple mass-action model, the contact parameter was 17% (95% confidence interval: 10, 25) lower during holidays than during termtime. Results were robust to the assumed proportions of infections that were reported and individuals who were susceptible when the influenza season started. We conclude that school closure may reduce transmission during influenza outbreaks.

Studies on cancer in migrants are informative about the relative influence of environmental and genetic factors on cancer risk. This study investigates trends in incidence from colorectal, lung, breast and prostate cancer in England among South Asians and examines the influence of deprivation, a key environmental exposure. South Asian ethnicity was assigned to patients recorded in the population-based National Cancer Registry of England during 1986-2004, using the computerized algorithm SANGRA: South Asian Names and Groups Recognition Algorithm. Population denominators were derived from population censuses. Multivariable flexible (splines) Poisson models were used to estimate trends and socioeconomic differentials in incidence in South Asians compared to non-South Asians. Overall, age-adjusted cancer incidence in South Asians was half that in non-South Asians but rose over time. Cancer-specific incidence trends and patterns by age and deprivation differed widely between the two ethnic groups. In contrast to non-South Asians, lung cancer incidence in South Asians did not fall. Colorectal and breast cancer incidence rose in both groups, more steeply in South Asians though remaining less common than in non-South Asians. The deprivation gaps in cancer-specific incidence were much less marked among South Asians, explaining some of the ethnic differences in overall incidence. Although still lower than in non-South Asians, cancer incidence is rising in South Asians, supporting the concept of transition in cancer incidence among South Asians living in England. Although these trends vary by cancer, they have important implications for both prevention and anticipating health-care demand.

To describe Ontario Telehealth usage for respiratory complaints during normal (i.e., interpandemic) circumstances.Descriptive analyses were conducted on symptom calls of a respiratory nature made to Ontario (Canada) Telehealth during a 25-month period.Approximately 300,000 calls were made during the period under study, peaking annually in January/February. Calls were above average during the weekend and Mondays (p0.0001). All-ages consultation rate was 0.21/1,000 (range, 0.11-0.43). Standardized call rates suggested an inverse relationship between age and call rate (except for65 years of age). During peak activity, weekly telehealth call rates were up to more than twice the weekly mean and up to four times as high as the lowest weekly rate. Highest call rate was for under 5 years old (158.4/1,000). Male rates exceed female call rates in younger age groups; the pattern reversed in older age groups. The relationship between income and call pattern showed that income and call patterns were (1) directly related for under 5 years old, (2) inversely related for callers aged 45 years and above, and (3) bimodal (higher call rates in both the highest and lowest income groups) for callers 5-44 years old.The advent of annual respiratory illness seasons under study here resulted in surge capacity. Data such as these can and should be used for exercises such as seasonal and pandemic forecasting. Also, recent pandemic experience has showed us monitoring both overall exceedances in usage and deviances from established demographic patterns could enhance existing routine surveillance.

Estimation of influenza vaccine effectiveness (VE) is complicated by various degrees of mismatch between circulating and vaccine strains each season. We carried out a cohort study to estimate VE of trivalent (TIV) and pandemic influenza vaccines (PIV) in preventing various respiratory outcomes among general practice (GP) patients in England and Wales between 2008 and 2010. Dates of consultations for influenza-like illness (ILI), acute respiratory tract infection (ARTI), lower respiratory tract infection (LRTI) and nasopharyngeal swabs were obtained from the patient-level electronic records of the 100 practices enrolled in a national GP network. Dates of vaccination with TIV and PIV were also extracted. Confounders including age, time period and consultation frequency were adjusted for through Poisson regression models. In the winter of 2008/9, adjusted VE of TIV in preventing ILI was 22.3% (95% CI 13.5%, 30.2%). During the 2009/10 winter VE for PIV in preventing ILI was 21.0% (5.3%, 34.0%). The VE for PIV in preventing PCR-confirmed influenza A/H1N1 (2009) was 63.7% (-6.1%, 87.6%). TIV during the period of influenza circulation of 2008/9 and PIV in the winter of 2009/10 were effective in preventing GP consultations for ILI. The cohort study design could be used each season to estimate VE; however, residual confounding by indication could still present issues, despite adjustment for propensity to consult.

Setting The state of Sabah contributes one third of the tuberculosis (TB) cases in Malaysia. Objective To collect information on factors that affect the time period from the onset of symptoms to first contact with health care providers, whether private or government. Design A cross-sectional study using a pre-tested questionnaire was conducted among 296 newly registered smear-positive TB patients in 10 districts in Sabah. Univariable and multivariable analyses were used to determine which risk factors were associated with patient delay (>30 days) and 'extreme' patient delay (>90 days). Results The percentage of patients who sought treatment after 30 and 90 days was respectively 51.8% (95%CI 45.7-57.9) and 23.5% (95%CI 18.6-29.0). The strongest factors associated with patient delay and 'extreme' patient delay was when the first choice for treatment was a non-government health facility and in 30-39-year-olds. 'Extreme' patient delay was also weakly associated, among other factors, with comorbidity and livestock ownership. Conclusion Delay and extreme delay in seeking treatment were more common when the usual first treatment choice was a non-government health facility. Continuous health education on TB aimed at raising awareness and correcting misconceptions is needed, particularly among those who use non-government facilities.

Live bird markets (LBMs) act as a network ‘hub’ and potential reservoir of infection for domestic poultry. They may therefore be responsible for sustaining H5N1 highly pathogenic avian influenza (HPAI) virus circulation within the poultry sector, and thus a suitable target for implementing control strategies. We developed a stochastic transmission model to understand how market functioning impacts on the transmission dynamics. We then investigated the potential for rest days—periods during which markets are emptied and disinfected—to modulate the dynamics of H5N1 HPAI within the poultry sector using a stochastic meta-population model. Our results suggest that under plausible parameter scenarios, HPAI H5N1 could be sustained silently within LBMs with the time spent by poultry in markets and the frequency of introduction of new susceptible birds' dominant factors determining sustained silent spread. Compared with interventions applied in farms (i.e. stamping out, vaccination), our model shows that frequent rest days are an effective means to reduce HPAI transmission. Furthermore, our model predicts that full market closure would be only slightly more effective than rest days to reduce transmission. Strategies applied within markets could thus help to control transmission of the disease.

Background: Cancer mortality has been examined among ethnic South Asian migrants in England and Wales, but not by generation of migration. Methods: Using South Asian mortality records, identified by a name-recognition algorithm, and census information, age-standardised rates among South Asians, and South Asian vs non-South Asian rate ratios, were calculated. Results and conclusions: All-cancer rates in ethnic South Asians were half of those in non-South Asians in first-generation (all-cancer-standardised mortality ratio (SMR) in males 0.51 and in females 0.56) and subsequent-generation South Asians (SMR in males 0.43 and in females 0.36). The higher mortality in first-generation South Asians for liver (both sexes), oral cavity and gallbladder cancer (females), particularly marked among Bangladeshis, was reduced in subsequent generations.

Movement of poultry through markets is potentially important in the circulation and spread of highly pathogenic avian influenza. However little is understood about poultry market chains in Cambodia. We conducted a cross-sectional survey of 715 rural villagers, 123 rural, peri-urban and urban market sellers and 139 middlemen from six provinces and Phnom Penh, to evaluate live poultry movement and trading practices. Direct trade links with Thailand and Vietnam were identified via middlemen and market sellers. Most poultry movement occurs via middlemen into Phnom Penh making live bird wet markets in Phnom Penh a potential hub for the spread of H5N1 and ideal for surveillance and control.

In several countries, pregnant women are recommended seasonal influenza vaccination and identified as a priority group for vaccination in the event of a pandemic. We review the evidence for the risks of influenza and the risks and benefits of seasonal influenza vaccination in pregnancy. Data on influenza vaccine safety in pregnancy are inadequate, but the few published studies report no serious side-effects in women or their infants, including no indication of harm from vaccination in the first trimester. National policies differ widely, mainly because of the limited data available, particularly on vaccination in the first trimester. The evidence of excess morbidity during seasonal influenza supports vaccinating healthy pregnant women in the second or third trimester and those with comorbidities in any trimester. The evidence of excess mortality in two previous influenza pandemics supports vaccinating in any trimester during a pandemic.

Data are limited regarding cancer incidence among Indians residing in different geographic regions around the world. Examining such rates may provide us with insights into future aetiological research possibilities as well as screening and prevention.Incidence rates for all cancers combined and 19 specific cancers were obtained for India from Globocan 2002, for Indians in Singapore from Cancer Incidence in Five Continents (VIII), and from national data sources for South Asians (SA) in the United Kingdom (UK) and for Asian Indians/Pakistanis (AIP) and whites in the United States (US).We observed the lowest total cancer incidence rates in India (111 and 116 per 100,000 among males and females, respectively, age-standardized to the 1960 world population) and the highest among US whites (362 and 296). Cancer incidence rates among Indians residing outside of India were: intermediate Singapore (102 and 132), UK (173 and 179) and US ranges 152-176 and 142-164. A similar pattern was observed for cancers of the colorectum, prostate, thyroid, pancreas, lung, breast and non-Hodgkin lymphoma. In contrast, rates for cancers of the oral cavity, oesophagus, larynx and cervix uteri were highest in India. Although little geographic variability was apparent for stomach cancer incidence, Indians in Singapore had the highest rates compared with any other region. The UK SA and the US AIP appear with adopt the cancer patterns of their host country.Variations in environmental exposures such as tobacco use, diet and infection, as well as better health care access and knowledge may explain some of the observed incidence differences.

Cancer is perceived to be a low priority public health issue in South Asians. Yet changing lifestyles and environments towards those of the majority population are shifting epidemiological patterns. Similar patterns will occur in other disease areas. Lack of community awareness of these changes will result in increased exposure to risk factors, poor uptake in screening and delayed clinical presentation.

Summary Background Little is known about how long the BCG vaccine protects against tuberculosis. We assessed the long-term vaccine effectiveness (VE) in Norwegian-born individuals. Methods In this retrospective population-based cohort study, we studied Norwegian-born individuals aged 12–50 years who were tuberculin skin test (TST) negative and eligible for BCG vaccination as part of the last round of Norway's mandatory mass tuberculosis screening and BCG vaccination programme between 1962 and 1975. We excluded individuals who had tuberculosis before or in the year of screening and those with unknown TST and BCG status. We obtained TST and BCG information and linked it to the National Tuberculosis Register, population and housing censuses, and the population register for emigrations and deaths. We followed individuals up to their first tuberculosis episode, emigration, death, or Dec 31, 2011. We used Cox regressions to estimate VE against all tuberculosis and just pulmonary tuberculosis by time since vaccination, adjusted for age, time, county-level tuberculosis rates, and demographic and socioeconomic indicators. Findings Median follow-up was 41 years (IQR 32–49) for 83 421 BCG-unvaccinated and 44 years (41–46) for 297 905 vaccinated individuals, with 260 tuberculosis episodes. Tuberculosis rates were 3·3 per 100 000 person-years in unvaccinated and 1·3 per 100 000 person-years in vaccinated individuals. The adjusted average VE during 40 year follow-up was 49% (95% CI 26–65), although after 20 years, the VE was not significant (up to 9 years VE [excluding tuberculosis episodes in the first 2 years] 61% [95% CI 24–80]; 10–19 years 58% [27–76]; 20–29 years 38% [–32 to 71]; 30–40 years 42% [–24 to 73]). VE against pulmonary tuberculosis up to 9 years (excluding tuberculosis episodes in the first 2 years) was 67% (95% CI 27–85), 10–19 years was 63% (32–80), 20–29 years was 50% (−19 to 79), and 30–40 years was 40% (−46 to 76). Interpretation Findings are consistent with long-lasting BCG protection, but waning of VE with time. The vaccine could be more cost effective than has been previously estimated Funding Norwegian Institute of Public Health and London School of Hygiene & Tropical Medicine.

Background: South Asian migrants show lower cancer incidence than their host population in England for most major cancers. We seek to study the ethnic differences in survival from cancer. Methods: We described and modelled the effect of ethnicity, time, age and deprivation on survival for the five most incident cancers in each sex in South Asians in England between 1986 and 2004 using national cancer registry data. South Asian ethnicity was flagged using the validated name-recognition algorithm SANGRA (South Asian Names and Group Recognition Algorithm). Results: We observed survival advantage in South Asians in earlier periods. This ethnic gap either remained constant or narrowed over time. By 2004, age-standardised net survival was comparable for all cancers except three in men, where South Asians had higher survival 5 years after diagnosis: colorectal (58.9% vs 53.6%), liver (15.0% vs 9.4%) and lung (15.9% vs 9.3%). Compared with non-South Asians, South Asians experienced a slower increase in breast and prostate cancer survival, both cancers associated with either a screening programme or an early diagnosis test. We did not find differential patterns in survival by deprivation between both ethnicities. Conclusions: Considering recent survival trends, appropriate action is required to avoid deficits in cancer survival among South Asians in the near future.

Self-report of polysaccharide pneumococcal vaccination is not thought reliable because of the increased risk of adverse events from inadvertent re-vaccination in elderly people. Some studies suggest a high sensitivity of self-report and hence a low risk of adverse events if vaccination is administered when medical records are unavailable. Self-report of pneumococcal and influenza vaccination in a sample of >64-year-olds in the United Kingdom was compared with information in their medical records. Self-report of pneumococcal vaccination, in contrast to some of the other studies had a low sensitivity. The findings here support the need for accurate knowledge of prior vaccine status before offering the polysaccharide pneumococcal vaccine. The study also confirms that self-report of influenza vaccination could be relied upon if rapid knowledge of uptake is required.

BCG uptake among infants in England has not been measured since targeted infant vaccination replaced universal schoolchildren vaccination in 2005, mainly because of the challenges in defining denominators. We estimated uptake between 2006 and 2008 by dividing number of BCG doses administered to infants by number of all live births (where BCG vaccination is universal) or ethnic minority/Eastern Europeans live births (where infant-BCG vaccination is selective). Weighted average uptake was 68% (95% CI 65% to 71%), slightly higher in primary care trusts with universal (72% (95% CI 64% to 80%)) than selective (66% (95% CI 61% to 70%)) policy; and also 13% higher in areas vaccinating in postnatal wards compared with community settings.

This study investigates whether intake of phyto-oestrogens is associated with breast cancer risk in South Asian women from the Indian subcontinent, whose diet is rich in pulses and vegetables but poor in soyfoods.A total of 240 South Asian breast cancer cases living in England and 477 age-matched population-based controls were recruited into the study. Dietary intake was measured using a validated food frequency questionnaire. Conditional logistic regression models were used to estimate the effect of phyto-oestrogen intake on breast cancer risk.After adjustment for known breast cancer risk factors and total energy intake, there was moderate evidence of a dose-effect response in the odds of breast cancer with isoflavone intake (p-value for trend 0.08), with women in the top quartile having approximately half the odds of breast cancer of those in the bottom one (odds ratio (OR) 0.58, 95% confidence interval (CI) 0.33, 1.00) but with no reductions in the odds for women in the second and third quartiles. The ORs for second, third and highest quartiles of total lignan intake compared to the lowest were 0.78 (95% CI 0.48, 1.26), 0.74 (0.46, 1.19) and 0.66 (0.41, 1.07), respectively, again with moderate evidence of a linear dose-effect response (p-value for trend 0.09). Further adjustment for non-startch polysaccharides (NSP) intake slightly weakened the phyto-oestrogens-breast cancer associations.These findings are consistent with the possibility that high phyto-oestrogen intake may protect against breast cancer, but further research is required to confirm this hypothesis.

The South Asian population is one of the largest minority ethnic groups in the United Kingdom (UK), forming 2.7% of the UK population. Risk of diseases such as CHD, NIDDM is high in South Asians and risk of cancer low in this population compared both to the native UK population and other migrant groups. It is useful to investigate the experience of disease and dietary exposures for aetiological clues in South Asians. The FFQ was designed for a population-based case-control study of diet and breast cancer. To validate a food frequency questionnaire (FFQ) to assess macro- and micronutrient intake among South Asians in the United Kingdom (UK). A one-year long study of current diet was conducted using monthly telephone 24-hour recalls followed by administration of an interviewer-administered FFQ to ascertain usual diet during this period. General practices in the Thames and West Midlands regions, England were used to sequentially recruit 100 women from a larger random sample of South Asian migrants from general practitioners’ patient lists participating as controls in a case-control study of diet and breast cancer. A total of 133 women were invited to achieve the final sample of 100 (76% response rate). The proportion of individuals classified by the two dietary assessment methods into the same or adjacent quartiles was high ranging from 65% (vitamin A) to 96% (protein). Misclassification into opposite quartiles was very low (0 % to 5 %), except for vitamin A (10 %). Energyadjusted Spearman correlation coefficients were reasonable for almost all nutrients being highest for protein (0.76), NSP (0.71), folate (0.70) and cholesterol (0.69). Correction for within-person variation in monthly 24-hour recalls had little effect on the magnitude of the nutrient correlations between the FFQ and the 24-hour recalls. Calibration coefficients to correct relative risks for nutrient-disease associations were above 0.50 for most nutrients indicating that the degree of attenuation introduced by the FFQ would be acceptable. This FFQ was specifically designed for South Asian women in the UK. Despite the diversity of diets, the FFQ had reasonable validity. The role of diet in breast cancer disease aetiology in this population is being assessed with this instrument. The study was supported by Cancer Research UK.

South Asian women in England have a lower breast cancer risk than their English-native counterparts, but less is known about variations in risk between distinct South Asian ethnic subgroups. We used the data from a population-based case-control study of first-generation South Asian migrants to assess risks by ethnic subgroup. In all, 240 breast cancer cases, identified through cancer registries, were individually matched on age and general practitioner to two controls. Information on the region of origin, religious and linguistic background, and on breast cancer risk factors was obtained from participants. Breast cancer odds varied significantly between the ethnic subgroups (P=0.008), with risk increasing in the following order: Bangladeshi Muslims (odds ratio (OR) 0.33, 95% confidence interval (CI): 0.10, 1.06), Punjabi Hindu (OR 0.59, 95% CI: 0.33, 1.27), Gujarati Hindu (1=reference group), Punjabi Sikh (OR 1.23, 95% CI: 0.72, 2.11) and Pakistani/Indian Muslims (OR 1.76, 95% CI: 1.10, 2.81). The statistically significant raised risk in Pakistani/Indian Muslims increased with adjustment for socioeconomic and reproductive risk factors (OR 2.12, 95% CI: 1.25, 3.58), but was attenuated, and no longer significant, with further adjustment for waist circumference and intake of nonstarch polysaccharides and fat (OR 1.49, 95% CI: 0.85, 2.63). These findings reveal differences in breast cancer risk between South Asian ethnic subgroups, which were not fully explained by reproductive differences, but were partly accounted for by diet and body size.

We review studies on the efficacy against disease caused by Streptococcus pneumoniae of the 23-valent polysaccharide pneumococcal vaccine in adult populations in the more developed countries. Meta-analyses of primary vaccine trials have attempted to reduce uncertainty from lack of power. Vaccine efficacy calculated from studies in South African gold-miners and in Papua New Guinea, with high attack rates and differing serotype patterns, cannot automatically be applied to more developed countries. Meta-analyses will overestimate a protective effect if this clinical heterogeneity is ignored. Meta-analyses limited to trials in the more developed setting show no protective effect against pneumococcal pneumonia and a non-significant protective effect against bacteraemia. Lack of a specific diagnosis limits the ability to detect a protective effect against pneumococcal pneumonia. Most, but not all, observational studies confirm a protective effect against bacteraemia. An effect on mortality in more developed countries has yet to be documented.

Vaccine-preventable infectious diseases are responsible for significant maternal, neonatal, and young infant morbidity and mortality. While there is emerging scientific evidence, as well as theoretical considerations, indicating that certain vaccines are safe for pregnant women and fetuses, policy formulation is challenging because of perceived potential risks to the fetus. This report presents an overview of available evidence on pregnant women vaccination safety monitoring in pregnant women, from both published literature and ongoing surveillance programs. Safety data were reviewed for vaccines against diseases which increase morbidity in pregnant women, their fetus or infant as well as vaccines which are used in mass vaccination campaigns against diseases. They include inactivated seasonal and pandemic influenza, mono- and combined meningococcal polysaccharide and conjugated vaccines, tetanus toxoid and acellular pertussis combination vaccines, as well as monovalent or combined rubella, oral poliomyelitis virus and yellow fever vaccines. No evidence of adverse pregnancy outcomes has been identified from immunization of pregnant women with these vaccines.

BACKGROUND: Studies on ethnic variations in health have played an important role in aetiological and health services research. Most routine datasets, however, do not include information on ethnicity. South Asians, one of the largest minority ethnic groups in Britain, have distinctive names that also allow differentiation of the main sub-groups with their important differences in health-related exposures and disease risks. METHODS: A computerized name recognition algorithm (SANGRA) was developed incorporating directories of South Asian first names and surnames together with their religious and linguistic origin. SANGRA was validated using health-related data with self-ascribed information on ethnicity. RESULTS: SANGRA was successful in recognizing South Asian origin in reference datasets, with sensitivity of 89-96 per cent, specificity of 94-98 per cent, positive predictive value (PPV) of 80-89 per cent and negative predictive value (NPV) of 98-99 per cent. Religious origin was correctly assigned in the majority of cases: sensitivity, specificity and PPV were 94 per cent, 91 per cent and 90 per cent for Hindus; 90 per cent, 99 per cent and 98 per cent for Muslims; and 76 per cent, 99 per cent and 94 per cent for Sikhs. SANGRA correctly identified 76 per cent Gujerati and 70 per cent Punjabi names, although only 62 per cent of Gujerati names were sufficiently distinct to be allocated to the Gujerati-only category and only 53 per cent Punjabi names were allocated to the Punjabi-only category. However, specificity and PPV were high for both languages (respectively 97 per cent and 93 per cent for Gujerati, and 99 per cent and 97 per cent for Punjabi). CONCLUSIONS: SANGRA provides a practical and valid method of ascertaining South Asian origin by name and, to a lesser degree of accuracy, of differentiating between the main religious and linguistic subgroups living in Britain. This algorithm will be useful in health-related studies where information on self-ascribed ethnicity is not available or is of a limited nature.

Summary Objectives: To develop an interview-administered food-frequency questionnaire (FFQ) to assess usual long-term intake of foods and nutrients amongst women from the largest South Asian communities residing in Britain. Methods: A list of foods and dishes consumed by these South Asian communities was compiled from data collected in previous studies. Foods which contributed to interindividual variation in the intake of the various macronutrients or were rich in fat or fibre were included in the FFQ. Portion size for traditional foods were estimated using sets of eight colour photographs. A nutrient database was modified to make it appropriate for South Asian diets. The reliability of the FFQ was assessed in a group of volunteer South Asian women (n=14) of differing regional and religious backgrounds. A preliminary validation exercise was conducted in a group of Punjabi Muslim women (n=11) who had kept 7-day weighed records 2 years previously. Results: The reliability of this FFQ was high, with most women being classified in the same tertile for energy and macronutrient intake in the two interviews. The main sources of energy and macronutrients identified by the FFQ were similar to those identified by the weighed records but the average nutrient intakes estimated by the FFQ were slightly higher. The level of agreement between the two dietary methods, measured by the ability of the FFQ to classify women in the same tertile of intake as the weighed records, was high for percentage energy intake from fat, protein and carbohydrates, but less so for absolute nutrient intakes. These results were, however, limited because of the small sample size. Conclusions: This is the first FFQ specifically designed for South Asian communities in Britain. Despite the diversity of diets, these preliminary findings suggest it will be a useful and easy to administer tool in chronic disease epidemiology to obtain standardized information on long-term usual dietary intake from these communities. A more comprehensive validation of this FFQ is now underway.

BACKGROUND: Randomized trials assessing BCG vaccine protection against tuberculosis have widely varying results, for reasons that are not well understood. METHODS: We examined associations of trial setting and design with BCG efficacy against pulmonary and miliary or meningeal tuberculosis by conducting a systematic review, meta-analyses, and meta-regression. RESULTS: We identified 18 trials reporting pulmonary tuberculosis and 6 reporting miliary or meningeal tuberculosis. Univariable meta-regression indicated efficacy against pulmonary tuberculosis varied according to 3 characteristics. Protection appeared greatest in children stringently tuberculin tested, to try to exclude prior infection with Mycobacterium tuberculosis or sensitization to environmental mycobacteria (rate ratio [RR], 0.26; 95% confidence interval [CI], .18-.37), or infants (RR, 0.41; 95% CI, .29-.58). Protection was weaker in children not stringently tested (RR, 0.59; 95% CI, .35-1.01) and older individuals stringently or not stringently tested (RR, 0.88; 95% CI, .59-1.31 and RR, 0.81; 95% CI, .55-1.22, respectively). Protection was higher in trials further from the equator where environmental mycobacteria are less and with lower risk of diagnostic detection bias. These associations were attenuated in a multivariable model, but each had an independent effect. There was no evidence that efficacy was associated with BCG strain. Protection against meningeal and miliary tuberculosis was also high in infants (RR, 0.1; 95% CI, .01-.77) and children stringently tuberculin tested (RR, 0.08; 95% CI, .03-.25). CONCLUSIONS: Absence of prior M. tuberculosis infection or sensitization with environmental mycobacteria is associated with higher efficacy of BCG against pulmonary tuberculosis and possibly against miliary and meningeal tuberculosis. Evaluations of new tuberculosis vaccines should account for the possibility that prior infection may mask or block their effects.

BACKGROUND: Recent evidence suggests that the duration of protection by bacillus Calmette-Guerin (BCG) may exceed previous estimates with potential implications for estimating clinical and cost-efficacy. OBJECTIVES: To estimate the protection and duration of protection provided by BCG vaccination against tuberculosis, explore how this protection changes with time since vaccination, and examine the reasons behind the variation in protection and the rate of waning of protection. DATA SOURCES: Electronic databases including MEDLINE, Excerpta Medica Database (EMBASE), Cochrane Databases, NHS Economic Evaluation Database (NHS EED), Database of Abstracts of Reviews of Effects (DARE), Web of Knowledge, Biosciences Information Service (BIOSIS), Latin American and Caribbean Health Sciences Literature (LILACs), MEDCARIB Database, Cumulative Index to Nursing and Allied Health Literature (CINAHL) were searched from inception to May 2009. Index to Theses, System for Information on Grey Literature in Europe (SIGLE), Centre for Agricultural Bioscience International (CABI) Abstracts, Scopus, Article First, Academic Complete, Africa-Wide Information, Google Scholar, Global Health, British National Bibliography for Report Literature, and clinical trial registration websites were searched from inception to October 2009. REVIEW METHODS: Electronic databases searches, screening of identified studies, data extraction and analysis were undertaken. Meta-analysis was used to present numerical and graphical summaries of clinical efficacy and efficacy by time since vaccination. Evidence of heterogeneity was assessed using the tau-squared statistic. Meta-regression allowed the investigation of observed heterogeneity. Factors investigated included BCG strain, latitude, stringency of pre-BCG vaccination tuberculin testing, age at vaccination, site of disease, study design and vulnerability to biases. Rate of waning of protection was estimated using the ratio of the measure of efficacy after 10 years compared with the efficacy in the first 10 years of a study. RESULTS: Study selection. A total of 21,030 references were identified, providing data on 132 studies after abstract and full-text review. Efficacy. Protection against pulmonary tuberculosis in adults is variable, ranging from substantial protection in the UK MRC trial {rate ratio 0.22 [95% confidence interval (CI) 0.16 to 0.31]}, to absence of clinically important benefit, as in the large Chingleput trial [rate ratio 1.05 (95% CI 0.88 to 1.25)] and greater in latitudes further away from the equator. BCG vaccination efficacy was usually high, and varied little by form of disease (with higher protection against meningeal and miliary tuberculosis) or study design when BCG vaccination was given only to infants or to children after strict screening for tuberculin sensitivity. High levels of protection against death were observed from both trials and observational studies. The observed protective effect of BCG vaccination did not differ by the strain of BCG vaccine used in trials. DURATION: Reviewed studies showed that BCG vaccination protects against pulmonary and extrapulmonary tuberculosis for up to 10 years. Most studies either did not follow up participants for long enough or had very few cases after 15 years. This should not be taken to indicate an absence of effect: five studies (one trial and four observational studies) provided evidence of measurable protection at least 15 years after vaccination. Efficacy declined with time. The rate of decline was variable, with faster decline in latitudes further from the equator and in situations where BCG vaccination was given to tuberculin-sensitive participants after stringent tuberculin testing. LIMITATIONS: The main limitation of this review relates to quality of included trials, most of which were conducted before current standards for reporting were formulated. In addition, data were lacking in some areas and the review had to rely on evidence from observational studies. CONCLUSIONS: BCG vaccination protection against tuberculosis varies between populations, to an extent that cannot be attributed to chance alone. Failure to exclude those already sensitised to mycobacteria and study latitude closer to the equator were associated with lower efficacy. These factors explained most of the observed variation. There is good evidence that BCG vaccination protection declines with time and that protection can last for up to 10 years. Data on protection beyond 15 years are limited; however, a small number of trials and observational studies suggest that BCG vaccination may protect for longer. Further studies are required to investigate the duration of protection by BCG vaccination. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

Objective To investigate the impact on mortality due to pneumonia or influenza of the change from risk-based to age group-based targeting of the elderly for yearly influenza vaccination in England and Wales. Design Excess mortality estimated using time series of deaths registered to pneumonia or influenza, accounting for seasonality, trend and artefacts. Non-excess mortality plotted as proxy for long-term trend in mortality. Setting England and Wales. Participants Persons aged 65–74 and 75+ years whose deaths were registered to underlying pneumonia or influenza between 1975/1976 and 2004/2005. Outcome measures Multiplicative effect on average excess pneumonia and influenza deaths each winter in the 4–6 winters since age group-based targeting of vaccination was introduced (in persons aged 75+ years from 1998/1999; in persons aged 65+ years from 2000/2001), estimated using multivariable regression adjusted for temperature, antigenic drift and vaccine mismatch, and stratified by dominant circulating influenza subtype. Trend in baseline weekly pneumonia and influenza death rates. Results There is a suggestion of lower average excess mortality in the six winters after age group-based targeting began compared to before, but the CI for the 65–74 years age group includes no difference. Trend in baseline pneumonia and influenza mortality shows an apparent downward turning point around 2000 for the 65–74 years age group and from the mid-1990s in the 75+ years age group. Conclusions There is weakly supportive evidence that the marked increases in vaccine coverage accompanying the switch from risk-based to age group-based targeting of the elderly for yearly influenza vaccination in England and Wales were associated with lower levels of pneumonia and influenza mortality in older people in the first 6 years after age group-based targeting began. The possible impact of these policy changes is observed as weak evidence for lower average excess mortality as well as a turning point in baseline mortality coincident with the changes.

OBJECTIVES: To describe the prevalence of sexually transmitted infection (STIs) in a sample of women who have sex with women (WSW) and to identify risk factors for the acquisition of STI. METHOD: Cross sectional survey. Questionnaire for demographic, sexual history, and sexual practice data linked with the results of genitourinary examination. 708 new patients attending two sexual health clinics for lesbians and bisexual women in London were surveyed. RESULTS: A majority of WSW reported sexual histories with men (82%). Bacterial vaginosis and candida species were commonly diagnosed (31.4% and 18.4% respectively). Genital warts, genital herpes, and trichomoniasis were infrequently diagnosed (1.6%, 1.1%, and 1.3% respectively). Chlamydia, pelvic inflammatory disease, and gonorrhoea infections were rare (0.6%, 0.3%, and 0.3% respectively) and diagnosed only in women who had histories of sex with men. CONCLUSIONS: Although we have demonstrated a low prevalence of STI, WSW may have sexual histories with men as well as women or histories of injecting drug use, and are therefore vulnerable to sexually transmitted or blood borne infections. Diagnosis of trichomoniasis, genital herpes, and genital warts in three women who had no history of sex with men implies that sexual transmission between women is possible.

Summary Setting: England and Wales, UK. Objective: To investigate: (1) whether misclassification of opportunistic mycobacterial disease had contributed to the failure of tuberculosis notifications to continue declining; (2) whether laboratory reports of Mycobacterium tuberculosis complex infections could be used to validate trends in the tuberculosis notification system. Design: Descriptive epidemiological study using laboratory reports of infections to the Public Health Laboratory Service Communicable Disease Surveillance Centre, Medical Research Council National Surveys of Tuberculosis and tuberculosis notifications to the Office of Population Censuses and Surveys. Results: Compared to 1983, an extra 1% of tuberculosis notifications in 1988 were opportunistic mycobacterial disease inappropriately notified as tuberculosis. On the basis of the expected proportion of microbiologically confirmed tuberculosis infections, laboratory reporting was incomplete: for one laboratory report there were four notifications. Conclusion: Misclassification of opportunistic mycobacterial infection was estimated to account for only a small proportion of the excess tuberculosis notifications since 1988. This excess of tuberculosis notifications could be due to artefact, for instance because a greater proportion of cases are being notified. Laboratory reports of tuberculosis infections are of limited use in validating the recent trends in tuberculosis notification rate. At present changes in the level of reporting of laboratory isolates are likely to obscure genuine trends.

Objectives: To investigate the association between four sociodemographic measures (unemployment, overcrowding, low social class, and the proportion of migrants from areas of high prevalence of tuberculosis) and average level and rate of change of notification rates for tuberculosis. Design: Ecological analysis of both the average and the rate of change of standardised annual notification rates for tuberculosis from 1982-91 and sociodemographic measures from the 1981 and 1991 censuses. Setting: 32 London boroughs. Subjects and data: Sociodemographic measures from the 1981 and 1991 censuses and tuberculosis notification rates for 1982-91. Main outcome measures: A measure of the association between average levels and rate of change in tuberculosis notification rates and four sociodemographic measures in 1981 and between the rate of change in tuberculosis notification rates between 1981 and 1991 and changes in sociodemographic measures between 1981 and 1991. Results: The average level of notifications was correlated with overcrowding and the proportion of migrants but not with unemployment or social class. No significant association was found between the rate of change in notification rates and sociodemographic measures in 1981. An association was found between increases in unemployment and the rate of change in notification rates, but the effect was small. Changes in the levels of unemployment explained 23% of the variation between boroughs in the rate of change in their notification rates. Conclusion: The average tuberculosis notification rates were related to overcrowding and the proportion of migrants in 1981. Only increases in unemployment from 1981 to 1991, however, were significantly associated with the rate of change in notifications over the same period. Key messages Key messages Sociodemographic variables such as poverty, overcrowding, and migration (from parts of the world with relatively high rates of tuberculosis) are known to be associated with higher rates of tuberculosis The recent rates of change in notification rates in London boroughs in the past decade do not seem to be associated with the absolute levels of overcrowding, unemployment, social class distribution, or proportion of migrants as measured in the 1981 census An association, however, was found between changes in unemployment levels between 1981 and 1991 and the rates of change in tuberculosis notification rates in the same period, but the effect was small Further research is necessary to determine the reasons for the association found and to investigate the other factors contributing to the changing rates of tuberculosis in the developed world

Objective: Assess the current BCG vaccination policies and delivery pathways for immunisation in Primary Care Trusts (PCTs) in England since the 2005 change in recommendations. Design: A survey of key informants across PCTs using a standardised, structured questionnaire. Setting: 152 PCTs in England. Results: Complete questionnaires were returned from 127 (84%) PCTs. Sixteen (27%) PCTs reported universal infant vaccination and 111 (73%) had selective infant vaccination. Selective vaccination outside infancy was also reported from 94 (74%) PCTs. PCTs with selective infant policy most frequently vaccinated on postnatal wards (51/102, 50%), whereas PCTs with universal infant vaccination most frequently vaccinated in community clinics (9/13, 69%; p=0.011). To identify and flag up eligible infants in PCTs with targeted infant immunisation, those who mostly vaccinate on postnatal wards depend on midwives and maternity records, whereas those who vaccinate primarily in the community rely more often on various healthcare professionals. Conclusions: Targeted infant vaccination has been implemented in most PCTs across the UK. PCTs with selective infant vaccination provide BCG vaccine via a greater variety of healthcare professionals than those with universal infant vaccination policies. Data on vaccine coverage would help evaluate the effectiveness of delivery. Interruptions of delivery noted here emphasise the importance of not just an agreed, standardised, local pathway, but also a named person in charge.

SUMMARYCompletion of treatment is key to tuberculosis control. Using national surveillance data we assessed factors associated with tuberculosis patients being lost to follow-up before completing treatment (‘lost’). Patients reported in England, Wales and Northern Ireland between 2001 and 2007 who were lost 12 months after beginning treatment were compared to those who completed, or were still on treatment, using univariable and multivariable logistic regression. Of 41 120 patients, men [adjusted odds ratio (aOR) 1·29; 95% confidence interval (CI) 1·23–1·35], 15- to 44-year-olds (P

Despite declining incidence in most high-income countries, tuberculosis shows no signs of disappearing in the near future. Although surveillance data from most Western European countries show relatively stable declines in the rate of tuberculosis over the past several decades, some have reported either an increasing rate or a decelerating pace of reduction in recent years. The burden of disease now disproportionately affects high-risk groups such as migrants, homeless persons, and prisoners. In view of the concentration of cases in urban areas and high-risk deprived groups, interventions that may not be efficient when applied to the general population may be highly cost effective when targeted at high-risk groups. In this article, we examine some controversial elements of tuberculosis prevention and control in low-burden countries and recommend issues for further research. In particular, we assess current evidence on the duration of protection by BCG vaccine, the screening of migrants and hard-to-reach groups, and the use of preventive therapy for contacts of cases of infectious multidrug-resistant tuberculosis. This analysis is presented from the perspective of low-tuberculosis-burden, high-income countries attempting to eliminate tuberculosis.

WHO estimates that in 2009, 9.4 million people developed tuberculosis and 1.7 million died of the disease worldwide. 1 In the UK, incidence has risen over the past two decades; most cases are in vulnerable groups such as migrants, people who are homeless, or those with a history of imprisonment.2 Bacillus Calmette Guerin (BCG) vaccine offers 70-80% efficacy against severe forms of tuberculosis in childhood, particularly meningitis in infancy.3 4 When given later in life, efficacy against tuberculosis (which, in adults, commonly presents as pulmonary disease) varies in different regions of the world, for reasons that are not clearly understood.3 5 The failure of BCG to protect adults in some populations—in particular in some studies in India6—has sometimes been wrongly generalised to suggest that BCG never protects against pulmonary disease. However, the Medical Research Council trial established that use of BCG in school age children in the UK was highly effective against tuberculosis (80%).7 On the basis of criteria from the International Union Against Tuberculosis and Lung Disease,8 universal BCG vaccination of school children with a negative tuberculin skin test (aimed at preventing the peak of tuberculosis in young adults in the UK) was discontinued in 2005. Current policy recommends vaccination in infancy of children in high risk groups to prevent severe forms of childhood tuberculosis,9 10 and this practice is cost effective.4 Uncertainty remains, however, about how long …

To determine how school closure for pandemic (H1N1) 2009 affected students’ contact patterns, we conducted a retrospective questionnaire survey at a UK school 2 weeks after the school reopened. School closure was associated with a 65% reduction in the mean total number of contacts for each student.

School-age children are at a high risk of acute respiratory virus infections including the 2009 pandemic influenza A(H1N1). School absence records have been suggested as a tool for influenza surveillance. We analysed absence records from six primary schools (children aged from around five to 11 years) in London during the years 2005 to 2007 in order to provide baseline epidemiological characteristics of illness-related school absence, and to correlate school absence with seasonal influenza. The daily average prevalence of absence due to illness was 2.9%. The incidence was 1.3% per person-day. The mean duration of absence was 1.8 days (SD 1.8). Over 60% of absence episodes lasted for one day. Absence prevalence did not differ by sex. Prevalence was highest in the youngest children and then declined slightly, but was again high again in the oldest. Absence was slightly higher on Mondays and Fridays. In general, peaks of absenteeism coincided with peaks of influenza A and B (laboratory reports) but several high peaks were not associated with influenza. There was a better correlation between absence and laboratory reports and prevalence compared to incidence. School absence data may be useful for the detection of localised school outbreaks and as an additional surveillance tool but are limited by lack of data on weekends and during holidays.

The use of the highly effective Haemophilus influenzae type b (Hib) conjugate vaccine has increased globally. We review the benefits and limitations of studies measuring Hib vaccine effectiveness (VE). We critically examine the case-control approach by assessing the similarities and differences in methodology and findings and discuss the need for future Hib VE studies. In the absence of good surveillance data, vaccine effectiveness studies can play an important role, particularly with the increasing use of pneumococcal vaccine that has not been well tested under field conditions in less developed countries. However, the effectiveness of Hib vaccine has been well documented so the need for future VE Hib studies is minimal.