Influenza: environmental remodeling, population dynamics and the need to understand networks

NEW CHALLENGES FOR PUBLIC HEALTH Emergence of new pathogens has been the reality of the 21st century; the role of animal reservoirs and changes in human behaviors may be the main key factors for disease dynamics. Human population growth and territory expansion has lead to habitat sharing between humans, domestic, wild animals and their pathogens; bringing new opportunities for spill over. Risk assessment regarding the main factors associated with potential reassortment and transmission between species should get to a stage where the analysis of wildlife networks and interactions with domestic animals and humans is well mapped. This last will allow an accurate prevention and control of hot spots of influenza transmission (4, 21). The challenge for all public health professionals lies upon the integration of the analysis of environment, animal reservoirs and human population as a whole and develop action plans accordingly to their interactions and not each of them separately (17,22,23). New animal production systems and human population dynamics has lead to different sources of infection that are not well understood. Although surveillance systems have improved considerably, the need for better communications and relations between environmental, health and agricultural sectors is essential for a precise prevention of disease appearance and dispersal. Interdisciplinary and Intersectorial help becomes imperative when assessing the risk factors; such as human interactions with animals, wildlife contact with animal production systems and environmental remodeling that contribute to disease emergence (19). In addition the assessment of hot spots of influenza transmission should be the tool to map animal habitats that are at most risk of encounters with domestic animals which might serve as a mixing vessel and as the source of infection for humans (25, 27) The emergence of influenza viruses is just one example of many diseases that have social and environmental factors that enhance their appearance and dispersal. The new strains that have emerged have social and environmental issues in common which contribute to the appearance of new viruses, or at least, to the spillover between species; and it is here where the efforts should focus (12,14). MULTICASUALITY, NETWORKS AND DISEASE EMERGENCE – INTERDICIPLINARY CALL The close interaction between humans and animals has determined many social behaviors, food availability and diseases present nowadays (1, 2). When humans domesticated animals they started to be in close contact not only with the animals but with the