A large-scale study of a poultry trading network in Bangladesh: implications for control and surveillance of avian influenza viruses

Since its first report in 2007, avian influenza (AI) has been endemic in Bangladesh. While live poultry marketing is widespread throughout the country and known to influence AI dissemination and persistence, trading patterns have not been described. The aim of this study is to assess poultry trading practices and features of the poultry trading networks which could promote AI spread, and their potential implications for disease control and surveillance. Data on poultry trading practices was collected from 849 poultry traders during a cross-sectional survey in 138 live bird markets (LBMs) across 17 different districts of Bangladesh. The quantity and origins of traded poultry were assessed for each poultry type in surveyed LBMs. The network of contacts between farms and LBMs resulting from commercial movements of live poultry was constructed to assess its connectivity and to identify the key premises influencing it

Adverse childhood experiences are associated with the risk of lung cancer: a prospective cohort study

Background. Strong relationships between exposure to childhood traumatic stressors and smoking behaviours inspire the question whether these adverse childhood experiences (ACEs) are associated with an increased risk of lung cancer during adulthood. Methods. Baseline survey data on health behaviours, health status and exposure to adverse childhood experiences (ACEs) were collected from 17,337 adults during 1995-1997. ACEs included abuse (emotional, physical, sexual), witnessing domestic violence, parental separation or divorce, or growing up in a household where members with mentally ill, substance abusers, or sent to prison. We used the ACE score (an integer count of the 8 categories of ACEs) as a measure of cumulative exposure to traumatic stress during childhood. Two methods of case ascertainment were used to identify incident lung cancer through 2005 follow-up: 1) hospital discharge records and 2) mortality records obtained from the National Death Index. Results. The ACE score showed a graded relationship to smoking behaviors. We identified 64 cases of lung cancer through hospital discharge records (age-standardized risk = 201 × 100,000-1 population) and 111 cases of lung cancer through mortality records (age-standardized mortality rate = 31.1 × 100,000 -1 person-years). The ACE score also showed a graded relationship to the incidence of lung cancer for cases identified through hospital discharge (P = 0.0004), mortality (P = 0.025), and both methods combined (P = 0.001). Compared to persons without ACEs, the risk of lung cancer for those with 6 ACEs was increased approximately 3-fold (hospital records: RR = 3.18, 95%CI = 0.71-14.15; mortality records: RR = 3.55, 95%CI = 1.25-10.09; hospital or mortality records: RR = 2.70, 95%CI = 0.94-7.72). After a priori consideration of a causal pathway (i.e., ACEs smoking lung cancer), risk ratios were attenuated toward the null, although not completely. For lung cancer identified through hospital or mortality records, persons with 6 ACEs were roughly 13 years younger on average at presentation than those without ACEs. Conclusions. Adverse childhood experiences may be associated with an increased risk of lung cancer, particularly premature death from lung cancer. The increase in risk may only be partly explained by smoking suggesting other possible mechanisms by which ACEs may contribute to the occurrence of lung cancer

Understanding Influenza

Influenza, a serious illness of humans and domesticated animals, has been studied intensively for many years. It therefore provides an example of how much we can learn from detailed studies of an infectious disease and of how even the most intensive scientific research leaves further questions to answer. This introduction is written for researchers who have become interested in one of these unanswered questions, but who may not have previously worked on influenza. To investigate these questions, researchers must not only have a firm grasp of relevant methods and protocols; they must also be familiar with the basic details of our current understanding of influenza. This article therefore briefly covers the burden of disease that has driven influenza research, summarizes how our thinking about influenza has evolved over time, and sets out key features of influenza viruses by discussing how we classify them and what we understand of their replication. It does not aim to be comprehensive, as any researcher will read deeply into the specific areas that have grasped their interest. Instead, it aims to provide a general summary of how we came to think about influenza in the way we do now, in the hope that the reader’s own research will help us to understand it better