A novel influenza A (H1N1) virus has spread rapidly across the globe. Judging its pandemic potential is difficult with limited data, but nevertheless essential to inform appropriate health responses. By analyzing the outbreak in Mexico, early data on international spread, and viral genetic diversity, we make an early assessment of transmissibility and severity. Our estimates suggest that 23,000 (range 6000 to 32,000) individuals had been infected in Mexico by late April, giving an estimated case fatality ratio (CFR) of 0.4% (range: 0.3 to 1.8%) based on confirmed and suspected deaths reported to that time. In a community outbreak in the small community of La Gloria, Veracruz, no deaths were attributed to infection, giving an upper 95% bound on CFR of 0.6%. Thus, although substantial uncertainty remains, clinical severity appears less than that seen in the 1918 influenza pandemic but comparable with that seen in the 1957 pandemic. Clinical attack rates in children in La Gloria were twice that in adults (<15 years of age: 61%; ≥15 years: 29%). Three different epidemiological analyses gave basic reproduction number (R0) estimates in the range of 1.4 to 1.6, whereas a genetic analysis gave a central estimate of 1.2. This range of values is consistent with 14 to 73 generations of human-to-human transmission having occurred in Mexico to late April. Transmissibility is therefore substantially higher than that of seasonal flu, and comparable with lower estimates of R0 obtained from previous influenza pandemics.

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Background: Physician adherence to hand hygiene remains low in most hospitals.Objectives: To identify risk factors for nonadherence and assess beliefs and perceptions associated with hand hygiene among physicians.Design: Cross-sectional survey of physician practices, beliefs, and attitudes toward hand hygiene.Setting: Large university hospital.Participants: 163 physicians.Measurements: Individual observation of physician hand hygiene practices during routine patient care with documentation of relevant risk factors; self-report questionnaire to measure beliefs and perceptions. Logistic regression identified variables independently associated with adherence.Results: Adherence averaged 57% and varied markedly across medical specialties. In multivariate analysis, adherence was associated with the awareness of being observed, the belief of being a role model for other colleagues, a positive attitude toward hand hygiene after patient contact, and easy access to hand-rub solution. Conversely, high workload, activities associated with a high risk for cross-transmission, and certain technical medical specialties (surgery, anesthesiology, emergency medicine, and intensive care medicine) were risk factors for nonadherence.Limitations: Direct observation of physicians may have influenced both adherence to hand hygiene and responses to the self-report questionnaire. Generalizability of study results requires additional testing in other health care settings and physician populations. H and hygiene is recognized as the leading measure to prevent cross-transmission of microorganisms and to reduce the incidence of health care-associated infections (1, 2). Despite the relative simplicity of this procedure, adherence to hand hygiene recommendations is unacceptably low, usually well below 50% (1-4). Risk factors for nonadherence have been extensively studied (1, 4 -7), and physicians have been repeatedly observed as being poor compliers (1,3,4,8,9). ConclusionAt our hospital, physician behavior did not improve substantially despite a hospital-wide hand hygiene promotion campaign that had a positive and marked effect on adherence among all other health care workers (1). That study highlighted the need for improved knowledge of behavior determinants among physicians.Promotion of hand hygiene behavior is a complex issue (7, 10 -12). Adherence to hand hygiene recommendations is influenced by knowledge; awareness of personal and group performance; workload; and type, tolerance, and accessibility of hand hygiene agents (2,4,12). Over the past 50 years in particular, the assumption that an individual's perceptions have a strong effect on his or her behavior gave birth to social cognitive models of human behavior (13). Some of these models have been applied to individual factors (that is, knowledge, attitude, intentions, beliefs, and perceptions) to help build strategies that improve specific health behaviors (14). To date, individual cognitive factors related to hand hygiene have not been adequately studied among physicians. Our study aim...

SummaryBackgroundA serogroup A meningococcal polysaccharide–tetanus toxoid conjugate vaccine (PsA–TT, MenAfriVac) was licensed in India in 2009, and pre-qualified by WHO in 2010, on the basis of its safety and immunogenicity. This vaccine is now being deployed across the African meningitis belt. We studied the effect of PsA–TT on meningococcal meningitis and carriage in Chad during a serogroup A meningococcal meningitis epidemic.MethodsWe obtained data for the incidence of meningitis before and after vaccination from national records between January, 2009, and June, 2012. In 2012, surveillance was enhanced in regions where vaccination with PsA–TT had been undertaken in 2011, and in one district where a reactive vaccination campaign in response to an outbreak of meningitis was undertaken. Meningococcal carriage was studied in an age-stratified sample of residents aged 1–29 years of a rural area roughly 13–15 and 2–4 months before and 4–6 months after vaccination. Meningococci obtained from cerebrospinal fluid or oropharyngeal swabs were characterised by conventional microbiological and molecular methods.FindingsRoughly 1·8 million individuals aged 1–29 years received one dose of PsA–TT during a vaccination campaign in three regions of Chad in and around the capital N'Djamena during 10 days in December, 2011. The incidence of meningitis during the 2012 meningitis season in these three regions was 2·48 per 100 000 (57 cases in the 2·3 million population), whereas in regions without mass vaccination, incidence was 43·8 per 100 000 (3809 cases per 8·7 million population), a 94% difference in crude incidence (p<0·0001), and an incidence rate ratio of 0·096 (95% CI 0·046–0·198). Despite enhanced surveillance, no case of serogroup A meningococcal meningitis was reported in the three vaccinated regions. 32 serogroup A carriers were identified in 4278 age-stratified individuals (0·75%) living in a rural area near the capital 2–4 months before vaccination, whereas only one serogroup A meningococcus was isolated in 5001 people living in the same community 4–6 months after vaccination (adjusted odds ratio 0·019, 95% CI 0·002–0·138; p<0·0001).InterpretationPSA–TT was highly effective at prevention of serogroup A invasive meningococcal disease and carriage in Chad. How long this protection will persist needs to be established.FundingThe Bill & Melinda Gates Foundation, the Wellcome Trust, and Médecins Sans Frontères.