Phylogeography of influenza A H5N1 clade 2.2.1.1 in Egypt.

BACKGROUND: Influenza A H5N1 has killed millions of birds and raises serious public health concern because of its potential to spread to humans and cause a global pandemic. While the early focus was in Asia, recent evidence suggests that Egypt is a new epicenter for the disease. This includes characterization of a variant clade 2.2.1.1, which has been found almost exclusively in Egypt.We analyzed 226 HA and 92 NA sequences with an emphasis on the H5N1 2.2.1.1 strains in Egypt using a Bayesian discrete phylogeography approach. This allowed modeling of virus dispersion between Egyptian governorates including the most likely origin. RESULTS: Phylogeography models of hemagglutinin (HA) and neuraminidase (NA) suggest Ash Sharqiyah as the origin of virus spread, however the support is weak based on Kullback-Leibler values of 0.09 for HA and 0.01 for NA. Association Index (AI) values and Parsimony Scores (PS) were significant (p-value < 0.05), indicating that dispersion of H5N1 in Egypt was geographically structured. In addition, the Ash Sharqiyah to Al Gharbiyah and Al Fayyum to Al Qalyubiyah routes had the strongest statistical support. CONCLUSION: We found that the majority of routes with strong statistical support were in the heavily populated Delta region. In particular, the Al Qalyubiyah governorate appears to represent a popular location for virus transition as it represented a large portion of branches in both trees. However, there remains uncertainty about virus dispersion to and from this location and thus more research needs to be conducted in order to examine this.Phylogeography can highlight the drivers of H5N1 emergence and spread. This knowledge can be used to target public health efforts to reduce morbidity and mortality. For Egypt, future work should focus on using data about vaccination and live bird markets in phylogeography models to study their impact on H5N1 diffusion within the country.

Awareness and practices regarding zoonotic influenza prevention in Romanian swine workers.

BACKGROUND: Swine workers may play a key role in transmission of zoonotic influenza viruses. At the same time, little is known about the extent and effectiveness of influenza prevention programs for these at-risk workers. OBJECTIVES: To characterize practices and attitudes regarding zoonotic influenza transmission among swine workers in Romania. METHODS: We conducted a convenience survey of swine workers in Romania. The confidential survey included questions about awareness of zoonotic influenza risk, work tasks performed, flu vaccination status, and reported influenza-like illness. RESULTS: A total of 103 workers at seven farms completed the survey. The percentage of workers reporting concern about either contracting influenza from pigs or giving influenza to pigs was 78% and 70%, respectively. Although 60% of workers reported having a sick-leave policy at work, only 7% of workers reported receiving seasonal influenza vaccination during the past flu season. Only 5% of the workers reported flu-like illness during the past year while 3% of workers reported that pigs appeared sick with influenza over the same time period. The majority of workers reported using protective overalls and rubber boots during swine work, with lower rates of use of gloves. Reported use of respiratory protection was rare, and use of any personal protective equipment did not differ when pigs appeared ill. CONCLUSIONS: Despite awareness and concern regarding zoonotic influenza, Romanian swine workers report low rates of influenza vaccine or respiratory protection. As part of global pandemic influenza preparedness, enhanced prevention programs for swine workers should address such gaps.

Swine worker awareness and behavior regarding prevention of zoonotic influenza transmission.

ABSTRACT A convenience survey of swine workers on large and small commercial farms in the Northeast and Midwest United States regarding zoonotic influenza awareness and precautions was conducted. Workers reported low levels of concern regarding the risk of contracting influenza from swine, and were generally not aware of national guidelines for influenza prevention. Use of personal protective equipment (PPE) varied by task, N95 respirator use was rare, and no workers were enrolled in respirator programs. Reported influenza vaccination coverage was greater than the national average in 2009-2010, but declined in 2010-2011. Workers on large farms were more likely to use PPE in some tasks and to report using more precautions when pigs appeared ill. Although reporting low levels of concern regarding zoonotic influenza and low adherence to national influenza guidelines, swine workers reported making task-based and risk-based decisions about use of PPE, suggesting opportunities for enhanced prevention of zoonotic disease transmission.

Comparison of human and animal surveillance data for H5N1 influenza A in Egypt 2006-2011.

BACKGROUND: The majority of emerging infectious diseases are zoonotic (transmissible between animals and humans) in origin, and therefore integrated surveillance of disease events in humans and animals has been recommended to support effective global response to disease emergence. While in the past decade there has been extensive global surveillance for highly pathogenic avian influenza (HPAI) infection in both animals and humans, there have been few attempts to compare these data streams and evaluate the utility of such integration. METHODOLOGY: We compared reports of bird outbreaks of HPAI H5N1 in Egypt for 2006-2011 compiled by the World Organisation for Animal Health (OIE) and the UN Food and Agriculture Organization (FAO) EMPRESi reporting system with confirmed human H5N1 cases reported to the World Health Organization (WHO) for Egypt during the same time period. PRINCIPAL FINDINGS: Both human cases and bird outbreaks showed a cyclic pattern for the country as a whole, and there was a statistically significant temporal correlation between the data streams. At the governorate level, the first outbreak in birds in a season usually but not always preceded the first human case, and the time lag between events varied widely, suggesting regional differences in zoonotic risk and/or surveillance effectiveness. In a multivariate risk model, lower temperature, lower urbanization, higher poultry density, and the recent occurrence of a bird outbreak were associated with increased risk of a human case of HPAI in the same governorate, although the positive predictive value of a bird outbreak was low. CONCLUSIONS: Integrating data streams of surveillance for human and animal cases of zoonotic disease holds promise for better prediction of disease risk and identification of environmental and regional factors that can affect risk. Such efforts can also point out gaps in human and animal surveillance systems and generate hypotheses regarding disease transmission.

Human vs. animal outbreaks of the 2009 swine-origin H1N1 influenza A epidemic.

The majority of emerging infectious diseases are zoonotic in origin, including recently emerging influenza viruses such as the 2009 swine-origin H1N1 influenza A epidemic. The epidemic that year affected both human and animal populations as it spread globally. In fact, before the end of 2009, 14 different countries reported H1N1 infected swine. In order to better understand the zoonotic nature of the epidemic and the relationship between human and animal disease surveillance data streams, we compared 2009 reports of H1N1 infection to define the temporal relationship between reported cases in animals and humans. Generally, human cases preceded animal cases at a country-level, supporting the potential of H1N1 infection to be a "reverse zoonosis", and the value of integrating human and animal disease report data.

Sex differences in injury patterns among workers in heavy manufacturing.

The objective of the study was to determine if female workers in a heavy manufacturing environment have a higher risk of injury compared with males when performing the same job and to evaluate sex differences in type or severity of injury. By use of human resources and incident surveillance data for the hourly population at 6 US aluminum smelters, injuries that occurred from January 1, 1996, through December 21, 2005, were analyzed. Multivariate logistic regression, adjusted for job, tenure, and age category, was used to calculate odds ratios and 95% confidence intervals for female versus male injury risk for all injuries, recordable injuries, and lost work time injuries. The analysis was repeated for acute injuries and musculoskeletal disorder-related injuries separately. Female workers in this industry have a greater risk for sustaining all forms of injury after adjustment for age, tenure, and standardized job category (odds ratio = 1.365, 95% confidence interval: 1.290, 1.445). This excess risk for female workers persisted when injuries were dichotomized into acute injuries (odds ratio = 1.2) and musculoskeletal disorder-related injuries (odds ratio = 1.1). This study provides evidence of a sex disparity in occupational injury with female workers at higher risk compared with their male counterparts in a heavy manufacturing environment.

The relationships between lost work time and duration of absence spells: proposal for a payroll driven measure of absenteeism.

OBJECTIVE: To propose a standard measure of absenteeism (the work lost rate [WLR]) be included in future research to facilitate understanding and allow for translation of findings between scientific disciplines. METHODS: Hourly payroll data derived from "punch clock" reports was used to compare various measures of absenteeism used in the literature and the application of the proposed metric (N = 4000 workers). RESULTS: Unpaid hours and full absent days were highly correlated with the WLR (r = 0.896 to 0.898). The highest percentage of unpaid hours (lost work time) is captured by absence spells of 1 and 2 days duration. CONCLUSION: The proposed WLR metric captures: 1) The range and distribution of the individual WLRs, 2) the percentage of subjects with no unpaid hours, and 3) the population WLR and should be included whenever payroll data is used to measure absenteeism.

Use of employer administrative databases to identify systematic causes of injury in aluminum manufacturing.

BACKGROUND: Employer administrative files are an underutilized source of data in epidemiologic studies of occupational injuries. METHODS: Personnel files, occupational health surveillance data, industrial hygiene data, and a real-time incident and injury management system from a large multi-site aluminum manufacturer were linked deterministically. An ecological-level measure of physical job demand was also linked. This method successfully created a database containing over 100 variables for 9,101 hourly employees from eight geographically dispersed U.S. plants. RESULTS: Between 2002 and 2004, there were 3,563 traumatic injuries to 2,495 employees. The most common injuries were sprain/strains (32%), contusions (24%), and lacerations (14%). A multivariable logistic regression model revealed that physical job demand was the strongest predictor of injury risk, in a dose dependent fashion. Other strong predictors of injury included female gender, young age, short company tenure and short time on current job. CONCLUSIONS: Employer administrative files are a useful source of data, as they permit the exploration of risk factors and potential confounders that are not included in many population-based surveys. The ability to link employer administrative files with injury surveillance data is a valuable analysis strategy for comprehensively studying workplace injuries, identifying salient risk factors, and targeting workforce populations disproportionately affected.

Effects of a cost-sharing exemption on use of preventive services at one large employer.

In 2004, Alcoa introduced a new health benefit for a portion of its workforce, which eliminated cost sharing for preventive care while increasing cost sharing for many other services. In this era of increased consumerism, Alcoa's benefit redesign constituted an effort to reduce health care costs while preserving use of targeted services. Taking advantage of a unique natural experiment, we find that Alcoa was able to maintain rates of preventive service use. This evidence suggests that differential cost sharing can be used to preserve the use of critical health care services.

Use of medical insurance claims data for occupational health research.

OBJECTIVE: The objective of this study was to demonstrate that health claims data, widely available due to the unique nature of the U.S. healthcare system, can be linked to other relevant databases such as personnel files and exposure data maintained by large employers. These data offer great potential for occupational health research. METHODS: In this article, we describe the process for linking claims data to industrial hygiene exposure data and personnel files of a single large employer to conduct epidemiologic research. RESULTS: Our results demonstrate the ability to replicate previously published findings using commonly maintained data sets and illustrate methodological issues that may arise as newer hypotheses are tested in this way. CONCLUSIONS: Health claims files offer potential for epidemiologic research in the United States, although the full extent and guidelines for successful application await further clarification through empiric research.

Incidence of asthma among aluminum workers.

Exposures to respiratory irritants encountered in aluminum smelters in Europe, Australia, and New Zealand have been suggested as the cause of "potroom asthma." However, there remains disagreement in North America regarding the existence of this entity. This study was designed to assess whether asthma occurs excessively among potroom workers and if so, delineate dose-response relationships for possible causal risk factors. The asthma incidence ratio between potroom and nonpotroom workers after adjusting for smoking was 1.40. Although bivariate analyses showed a relationship between asthma incidence and exposure to total fluoride, gaseous fluoride, particulate fluoride, sulfur dioxide, and smoking, only the effects of gaseous fluoride (relative risk [RR] = 5.1) and smoking (RR = 7.7) remained significant in a multivariate model. Potroom asthma appears to occur at the studied U.S. aluminum smelters at doses within regulatory guidelines.