Understanding the evolution and spread of chikungunya virus in the Americas using complete genome sequences.

Local transmission of chikungunya virus (CHIKV) was first detected in the Americas in December 2013, after which it spread rapidly throughout the Caribbean islands and American mainland, causing a major chikungunya fever epidemic. Previous phylogenetic analysis of CHIKV from a limited number of countries in the Americas suggests that an Asian genotype strain was responsible, except in Brazil where both Asian and East/Central/South African (ECSA) lineage strains were detected. In this study, we sequenced thirty-three complete CHIKV genomes from viruses isolated in 2014 from fourteen Caribbean islands, the Bahamas and two mainland countries in the Americas. Phylogenetic analyses confirmed that they all belonged to the Asian genotype and clustered together with other Caribbean and mainland sequences isolated during the American outbreak, forming an 'Asian/American' lineage defined by two amino acid substitutions, E2 V368A and 6K L20M, and divided into two well-supported clades. This lineage is estimated to be evolving at a mean rate of 5 × 10-4 substitutions per site per year (95% higher probability density, 2.9-7.9 × 10-4) and to have arisen from an ancestor introduced to the Caribbean (most likely from Oceania) in about March 2013, 9 months prior to the first report of CHIKV in the Americas. Estimation of evolutionary rates for individual gene regions and selection analyses indicate that (in contrast to the Indian Ocean Lineage that emerged from the ECSA genotype followed by adaptive evolution and with a significantly higher substitution rate) the evolutionary dynamics of the Asian/American lineage are very similar to the rest of the Asian genotype and natural selection does not appear to have played a major role in its emergence. However, several codon sites with evidence of positive selection were identified within the non-structural regions of Asian genotype sequences outside of the Asian/American lineage.

Knowledge of Rabies Prevention in Vietnamese Public Health and Animal Health Workers.

Rabies is an invariably fatal, but preventable zoonotic disease. Despite a national programme for its prevention and control, the number of rabies associated deaths in Vietnam has increased in recent years. A cross-sectional survey was undertaken in 2012 to assess and compare the knowledge, awareness and practices of 189 public health workers (PHW) and animal health workers (AHW) attending a joint training course for professionals from provinces in northern Vietnam with the highest number of deaths from rabies. Questionnaires facilitating self-evaluation were provided, and total knowledge scores were calculated (maximum 38 points) and categorized into: 'high' (>30 points), 'moderate' (21-30) and 'low' (<21). The response rate was 100%, and among the 189 participants, 56% were PHW compared to 44% who were AHW. Although most respondents knew rabies could be transmitted through the bite of an animal, most commonly a dog, and that rabies is a preventable disease, significant differences between groups were identified. Major areas included poor knowledge of common rabies reservoirs, wound management and guidance on post-exposure prophylaxis. Overall, the total mean knowledge scores for PHW was significantly higher (P = 0.011) compared to those for AHW, but both scores fell within the 'moderate' knowledge range. However, proportionately more PHW than AHW achieved 'high' knowledge scores (P = 0.0098). To our knowledge this is the first published study to simultaneously assess the knowledge and awareness of animal health and public health professionals attending joint training activities aimed at strengthening rabies prevention and control. To ensure effective prevention and control of rabies requires that AHW and PHW not only coordinate and collaborate, but have a common knowledge and understanding of rabies prevention and control measures. This study provides important baseline data in a relatively unexplored area of research that can focus future interventions and research.

Awareness of rabies prevention and control measures among public health workers in Northern Vietnam.

OBJECTIVES: To assess and compare rabies related knowledge and awareness of public health workers at provincial and district levels in the seven provinces with the highest number of deaths from human rabies in northern Vietnam. STUDY DESIGN: A cross-sectional study. METHOD: A survey was administered to a convenience sample of public health workers attending four workshops on rabies disease, control and prevention between 16 October and 21 November, 2012. Total knowledge scores (maximum 38 points) were categorized into: 'high' (>30 points) 'moderate' (21-30) and 'low' (<21). The Chi-square test was used to evaluate the statistical significance of the differences in responses between the respondents. RESULTS: Of the 105 public health workers attending the workshops: 57% were male; 76% worked at the district level compared with 24% who worked at provincial level; and 45% had worked in rabies control for <1 year compared with 11% who had worked in rabies control for >5 years. Overall knowledge was patchy and ranked as 'moderate'. Important gaps in knowledge were identified particularly in relation to indications for rabies vaccine and rabies immunoglobulin, and routes of exposure to rabies virus. One in ten respondents did not know that rabies virus could be transmitted by the bite of an infected animal. When examining the overall mean knowledge scores, marginally significant differences were identified. The average scores for district level health workers (DLHW) and provincial level health workers (PLHW) were 28 ± 3 and 29 ± 3 points respectively (p = 0.098), which fell within the study definition of 'moderate' knowledge. In contrast, when 'high' knowledge scores were compared, a significantly greater proportion of PLHW achieved >30 points compared to DLHW (44.0% vs 22.5%, p = 0.044). CONCLUSIONS: Important gaps in knowledge and awareness of public health workers were identified particularly in relation to routes of exposure to rabies virus and indications for rabies vaccine and rabies immunoglobulin. Overall, comparison of knowledge scores revealed significant differences between district and provincial public health workers. The results obtained suggest that in order for rabies control programmes to succeed public health workers at all levels need to have accurate and evidence-based knowledge. This may be facilitated by improving the quantity and quality of their training and education.

The Caribbean Regional Field Epidemiology and Laboratory Training Programme (CR-FELTP): a new resource for building public health capacity

OBJECTIVE: To describe the process of developing and implementing the CR-FELTP. DESIGN AND METHODS: Caribbean countries have articulated a longstanding need for comprehensive training in applied and integrated epidemiology. Implementation of the International Health Regulations (IHR) (2005) illustrated public health capacity gaps in the region. The design of a regional FELTP was based on global FETP/FELTP curriculum standards, and the model of a 3-tiered regional FETP in Central America. CR-FELTP Level I reflects the “Tier 1” competencies for applied epidemiologists in governmental agencies, and includes training and field projects in 9 subject areas. RESULTS: A Level I curriculum including Mentor orientation, training materials, programme guide and evaluation framework, was developed and disseminated to countries, along with basic computer equipment for training. In 2014, the CR-FELTP was successfully launched in 6 Caribbean countries: Barbados, Suriname, Grenada, St Vincent and the Grenadines, the Bahamas and St Lucia. Along with a coordinator in each implementing country, 48 Mentors were recruited. A total of 71 Trainees have participated in Level I, yielding a 1.5 trainee : mentor ratio. CONCLUSIONS: FETP/FELTPs worldwide have demonstrated that they are an important and ongoing source of skilled public health professionals who contribute to strengthening surveillance systems and the public health workforce. The CR-FELTP shares these goals, but faces many challenges. With external fiscal support ending in 2015, maintaining momentum will require aggressive resource mobilisation, organisational commitment from CARPHA and its partners, and continued interest and commitment from member states.

Measuring the effect of influenza A(H1N1)pdm09: the epidemiological experience in the West Midlands, England during the 'containment' phase.

The West Midlands was the first English region to report sustained community transmission during the 'containment' phase of the influenza A(H1N1)pdm09 pandemic in England. To describe the epidemiological experience in the region, West Midlands and national datasets containing laboratory-confirmed A(H1N1)pdm09 virus cases in the region during the 'containment' phase were analysed. The region accounts for about 10·5% of England's population, but reported about 42% of all laboratory-confirmed cases. Altogether 3063 cases were reported, with an incidence rate of 56/100 000 population. School-associated cases accounted for 25% of cases. Those aged <20 years, South Asian ethnic groups, and residents of urban and socioeconomically deprived areas were disproportionately affected. Imported cases accounted for 1% of known exposures. Regional R 0 central estimates between 1·41 and 1·43 were obtained. The West Midlands experience suggests that interpretation of transmission rates may be affected by complex interactions within and between sub-populations in the region.

Challenges and lessons learned from implementing a risk-based approach to school advice and closure during the containment phase of the 2009 influenza pandemic in the West Midlands, England.

OBJECTIVE: School closure as a social distancing measure was used in some countries during the initial phases of the influenza A(H1N1)pdm09 pandemic. The objective of this paper is to describe the use of a risk-based approach to public health interventions for schools during the 'containment phase' of the pandemic and to describe lessons learnt. METHODS: The development of a framework for risk assessment and decision-making to determine school closures in the West Midlands, England, during the 'containment phase' of influenza A(H1N1)pdm09 pandemic is described. RESULTS: Using the framework developed during the 'containment phase', assessments were conducted for 344 educational institutions who reported confirmed cases or 'particularly high absenteeism'. Of these, 209 (60%) had confirmed cases and 65 were closed, mainly for public health or operational reasons. Schools were closed on an individual basis, during the most intense period of the pandemic and for an average period of six days (maximum 11 days). The risk-based approach evolved as experience and knowledge of influenza A(H1N1)pdm09 pandemic virus increased, however some decisions were difficult to communicate to parents, schools and stakeholders particularly when the number of schools affected escalated and the pandemic response phases changed. CONCLUSION: The management of school closures is an 'uncertain art'. Numerous challenges and lessons were identified in attempting, during the containment phase of the influenza A(H1N1)pdm09 pandemic, to ensure consistency and transparency in an increasingly complex process. The overall approach described could be further developed to improve decision-making for infectious diseases in schools.

Influenza A(H1N1)pdm09 and flu response centres: characteristics of flu response centre staff in the West Midlands.

OBJECTIVE: To assess the operational experience and knowledge of staff who worked in the West Midlands Flu Response Centre (FRC) during the 'containment' phase of influenza A(H1N1)pdm09. STUDY DESIGN: Evaluation study. METHODS: Cross-sectional survey of staff who worked in the West Midlands FRC between 18 May 2009 and 10 July 2009 using an online self-administered questionnaire. The questionnaire included sections related to the respondents' FRC experience, knowledge about influenza A(H1N1)pdm09 and the containment phase. RESULTS: This study had a 51% (89/176) response rate. Of the respondents, 59% were female, 64% were of White ethnicity, 55% were clinicians, 46% were aged 25-44 years, and 67% had no previous call centre experience. A significant proportion (P < 0.001) of respondents believed that the FRC had made a positive contribution to the public health management of the containment phase. Nearly all respondents indicated that they were familiar with the terms 'pandemic flu' or 'influenza pandemic' (99%), understood the aim of the containment phase (90%), and knew the severity of the illness caused by the virus (97%). However, specific knowledge was lacking regarding a number of public health interventions, and overall knowledge scores for clinicians and non-clinicians were similar. CONCLUSION: This study is the first to report on the characteristics of FRC staff during the containment phase of influenza A(H1N1)pdm09 pandemic. Although overall, staff evaluation of the West Midlands FRC was very positive, a number of knowledge gaps were identified. This study provides valuable insights which can contribute to preparedness planning.

Volume of print media coverage and diagnostic testing for influenza A(H1N1)pdm09 virus during the early phase of the 2009 pandemic.

BACKGROUND: Impact of an infectious disease on public health diagnostic health services may be affected by the volume of media coverage which can amplify risk perception and increase demand for services. OBJECTIVES: To examine the association between volume of newspaper reports and laboratory testing for influenza A(H1N1)pdm09 in one English health region during the early phase of the pandemic. STUDY DESIGN: Cross-sectional retrospective review identifying newspaper articles on A(H1N1)pdm09 in major regional (sub-national) newspapers from 27 April 2009 through 5 July 2009, and comparing the weekly frequency of articles with the weekly number, and positivity rate, of laboratory-confirmed cases of A(H1N1)pdm09 during the same time period. RESULTS: A positive correlation (r=0.67; p=0.02) was seen between the volume of school-related articles and the number of laboratory-confirmed cases. Increased testing during the most intense period of the pandemic was mainly seen in school-aged children (5-15 years) and adults (≥16 years). Adults accounted for the highest number of tests, but had the lowest positivity rates, which were highest among school-aged children. As the volume of media coverage decreased this was followed one week later by a fall in the number of tests and positivity rates in each age-group. CONCLUSION: The results presented suggest a temporal association between volume of media reporting and number of laboratory tests. The increased volume of media reporting, in particular the intense school-related coverage, may have raised population concern leading to an increased demand for diagnostic testing. These results have potential implications for future pandemic preparedness planning.

Absenteeism in schools during the 2009 influenza A(H1N1) pandemic: a useful tool for early detection of influenza activity in the community?

Certain influenza outbreaks, including the 2009 influenza A(H1N1) pandemic, can predominantly affect school-age children. Therefore the use of school absenteeism data has been considered as a potential tool for providing early warning of increasing influenza activity in the community. This study retrospectively evaluates the usefulness of these data by comparing them with existing syndromic surveillance systems and laboratory data. Weekly mean percentages of absenteeism in 373 state schools (children aged 4-18 years) in Birmingham, UK, from September 2006 to September 2009, were compared with established syndromic surveillance systems including a telephone health helpline, a general practitioner sentinel network and laboratory data for influenza. Correlation coefficients were used to examine the relationship between each syndromic system. In June 2009, school absenteeism generally peaked concomitantly with the existing influenza surveillance systems in England. Weekly school absenteeism surveillance would not have detected pandemic influenza A(H1N1) earlier but daily absenteeism data and the development of baselines could improve the timeliness of the system.

Early spread of the 2009 influenza A(H1N1) pandemic in the United Kingdom--use of local syndromic data, May-August 2009.

Following the confirmation of the first two cases of pandemic influenza on 27 April 2009 in the United Kingdom (UK), syndromic surveillance data from the Health Protection Agency (HPA)/QSurveillance and HPA/NHS Direct systems were used to monitor the possible spread of pandemic influenza at local level during the first phase of the outbreak. During the early weeks, syndromic indicators sensitive to influenza activity monitored through the two schemes remained low and the majority of cases were travel-related. The first evidence of community spread was seen in the West Midlands region following a school-based outbreak in central Birmingham. During the first phase several Primary Care Trusts had periods of exceptional influenza activity two to three weeks ahead of the rest of the region. Community transmission in London began slightly later than in the West Midlands but the rates of influenza-like illness recorded by general practitioners (GPs) were ultimately higher. Influenza activity in the West Midlands and London regions peaked a week before the remainder of the UK. Data from the HPA/NHS Direct and HPA/QSurveillance systems were mapped at local level and used alongside laboratory data and local intelligence to assist in the identification of hotspots, to direct limited public health resources and to monitor the progression of the outbreak. This work has demonstrated the utility of local syndromic surveillance data in the detection of increased transmission and in the epidemiological investigation of the pandemic and has prompted future spatio-temporal work.

The international follow-up of individuals potentially exposed to polonium-210 in London 2006.

OBJECTIVES: Following a death from polonium-210 ((210)Po), contamination was found at several sites in London. This paper describes the UK Health Protection Agency's follow-up and assessment of individuals resident overseas who were potentially exposed to (210)Po. STUDY DESIGN: Descriptive follow-up study. METHODS: Individuals were classified into three exposure groups (higher, lower and unknown). Presence and degree of internal contamination were measured by 24-h urinary (210)Po activity (mBq/day). Results over 30mBq/day were taken to indicate probable contact with (210)Po in this incident. Dose assessments were conducted to determine degree of exposure and to identify individuals requiring further follow-up. RESULTS: Overall, 664 potentially exposed persons from 52 countries and territories were identified. Of these, 157 (24%) were in the higher exposure category, and urinary measurements were reported for 31% (48/157). Results for 19% (9/48) of those at higher exposure were more than 30mBq/day. For those at lower exposure, the percentage was 4% (3/68). Results above 30mBq/day were significantly more likely to be reported for the higher exposure category than the lower exposure category (Fisher's exact test P=0.010). Reported dose assessments suggested that identified individuals were not at increased health risk in the long term. Challenges and practical lessons were identified during the investigation. CONCLUSION: The results suggest that it is unlikely that any overseas resident had significant internal contamination with (210)Po. However, this incident clearly demonstrated the scale of international involvement likely to be necessary in other public health emergencies in large cities. The lessons identified have implications for the international health community, particularly with regard to the follow-up of individuals exposed to radiation in one country who then travel to another.

Investigating a cluster of Legionnaires' cases: public health implications.

OBJECTIVES: To describe the multidisciplinary investigation and management of a rapidly increasing number of cases of Legionnaires' disease in the North Shropshire area, UK during August 2006. STUDY DESIGN: Epidemiological and environmental investigation of a cluster of cases of Legionnaires' disease. METHODS: Outbreak investigation included: agreeing case definitions; case finding; epidemiological survey; identification and environmental investigation of potential sources; microbiological analysis of clinical and environmental samples; mapping the location of potential sources; and the movement and residence of cases. RESULTS: Three cases of Legionnaires' disease were admitted to a local hospital between 30 and 31 August 2006. Two of these cases were Shropshire residents, with the third living in Wales. A fourth case was also identified which, it was thought, may have been linked to this cluster as the patient had a history of travel to the same area as the two Shropshire residents. Over the next few weeks, three more cases were identified, two of whom were admitted to hospital. Subsequent detailed environmental, epidemiological and microbiological investigation did not support the hypothesis that any of these cases could be linked to a common source. CONCLUSIONS: The results of this investigation strongly suggest that a single source was not responsible for the cluster, and it was concluded that this incident was a pseudo-outbreak. This investigation serves as a reminder that clusters can and do occur, and that an apparent outbreak may be a collection of sporadic cases distinguishable only by rigorous epidemiological, environmental and microbiological investigation.

Trends in sexually transmitted infections (other than HIV) in older people: analysis of data from an enhanced surveillance system.

OBJECTIVE: This study examines the distribution of selected sexually transmitted infections (STIs) in older people (aged >/=45 years) attending genitourinary medicine (GUM) clinics in the West Midlands, UK. METHODS: Analysis of data from the regional enhanced STI surveillance system for the period 1996-2003. Selected STIs were chlamydia, genital herpes, genital warts, gonorrhoea and syphilis. RESULTS: Altogether, 4445 STI episodes were reported among older people during the study period. Between 1996 and 2003 older people accounted for 3.7% and 4.3%, respectively, of all GUM clinic attendances. The rate of STIs in older people more than doubled in 2003 compared with 1996 (p<0.0001). Rates for all five selected diagnoses were significantly higher in 2003 compared to 1996. A significantly increasing trend over time was seen overall (p<0.0001) and for each of the selected diagnoses. Overall, males and those aged 55-59 years of age were significantly more likely to be affected. CONCLUSIONS: This study provides evidence of significant increases in attendance at GUM clinics by older people. Although it is recognised that young people should remain the focus of sexual health programmes, the results indicate that sexual risk-taking behaviour is not confined to young people but also occurs among older people. There is therefore a need to develop and implement evidence-based multifaceted sexual health programmes that while aiming to reduce STI transmission among all age groups should include interventions aimed specifically at older people and address societal and healthcare attitudes, myths and assumptions about sexual activity among older people.

A case-control study of elderly patients with acute respiratory illness: effect of influenza vaccination on admission to hospital in winter 2003-2004.

Every winter, hospitals face a large increase in emergency respiratory admissions in elderly people. A case-control study was undertaken to assess the effect of routine influenza vaccine in preventing such admissions among a cohort of UK elderly presenting with acute respiratory illness during winter 2003-2004. 157 hospitalised cases and 639 controls (matched for age, sex and week of consultation) were interviewed. In a winter typical of levels of circulating influenza in recent years, influenza vaccine did not show a protective effect on emergency respiratory admissions overall (adjusted OR 1.2 (95%CI 0.8, 1.9). Policy makers should not rely solely on influenza vaccine routinely having a large effect on winter pressures, and should focus on additional preventive strategies.

A survey of the preparedness for an influenza pandemic of general practitioners in the West Midlands, UK.

There is a lack of evidence regarding the preparedness of general practitioners (GPs) to respond to pandemic influenza. A postal questionnaire survey was conducted to explore the self-perceived pandemic preparedness of GPs in the West Midlands, United Kingdom, and to determine differences between urban and non-urban GPs. The postal questionnaire was sent out to 773 GPs in November 2005, and a reminder was sent in January 2006. In all, 427/773 (55%) questionnaires were returned, and 56% of respondents were aware of influenza pandemic preparedness plans. Approximately one-quarter of respondents (28%, 114/401) thought the response of their practice to a pandemic event would be very poor/poor. Non-urban GPs were significantly more likely to rate the response of their practice to a pandemic as likely to be poor (OR 3.01, 95%CI 1.03-8.76) and were less likely to be aware of pandemic preparedness plans (OR 0.62, 95%CI 0.39-0.99). Non-urban GPs were also significantly more likely to feel less confident in their ability to explain to their patients what to do and why during an influenza pandemic than GPs based in urban areas (OR 4.68, 95%CI 1.78-12.31). GPs rating of the odds of a pandemic affecting the United Kingdom did not differ significantly by geographic location. The results of this paper can be used to inform and influence public health policy and as evidence of a need to provide additional education and training to improve pandemic preparedness among GPs, in particular those in non-urban areas.

What women want: convenient appointment times for cervical screening tests.

Little is known about women's preferred appointment times for cervical screening tests. Data from a postal questionnaire survey were used to compare preferred appointment times with those given. Although 33.4%[95% confidence intervals (CI) 31.8%-35.0%] of respondents received appointments between 10h00 and 11h55, only 17.0% (95% CI 15.3%-18.7%) wanted an appointment at that time. Nineteen per cent (95% CI 17.4%-21.0%) of respondents wanted appointments between 18h00 and 20h00, but only 4.4% (95% CI 3.7%-5.1%) received them. Saturday appointments for cervical screening are not given; however, overall approximately 13% of those surveyed would have preferred a Saturday appointment. Preferred times also varied significantly with age and deprivation category. Further research is required to determine whether appointment times for cervical screening can be tailored to meet these expressed needs, and the impact this has on service provision and uptake.

Severe acute respiratory syndrome (SARS): knowledge, attitudes, practices and sources of information among physicians answering a SARS fever hotline service.

In June 2003, Taiwan introduced a severe acute respiratory syndrome (SARS) telephone hotline service to provide concerned callers with rapid access to information, advice and appropriate referral where necessary. This paper reports an evaluation of the knowledge, attitude, practices and sources of information relating to SARS among physicians who staffed the SARS fever hotline service. A retrospective survey was conducted using a self-administered postal questionnaire. Participants were physicians who staffed a SARS hotline during the SARS epidemic in Taipei, Taiwan from June 1 to 10, 2003. A response rate of 83% was obtained. All respondents knew the causative agent of SARS, and knowledge regarding SARS features and preventive practices was good. However, only 54% of respondents knew the incubation period of SARS. Hospital guidelines and news media were the major information sources. In responding to two case scenarios most physicians were likely to triage callers at high risk of SARS appropriately, but not callers at low risk. Less than half of all respondents answered both scenarios correctly. The results obtained suggest that knowledge of SARS was generally good although obtained from both medical and non-medical sources. Specific knowledge was however lacking in certain areas and this affected the ability to appropriately triage callers. Standardized education and assessment of prior knowledge of SARS could improve the ability of physicians to triage callers in future outbreaks.