FAO-OIE-WHO Joint Technical Consultation on Avian Influenza at ...

<strong>FAO</strong>-<strong>OIE</strong>-<strong>WHO</strong> <strong>Joint</strong> <strong>Technical</strong> <strong>Consultation</strong> on Avian Influenza at the Human-Animal Interfacesurveillance may not be implemented properly, even if thesystem is appropriately written in the national legislation.Surveillance systems in humans should also vary by the diseasesituation. For example, where AIVs are endemic andsporadic human cases are occurring, it was suggested thatit would be most efficient to focus on the early identificationof clusters of human cases.The social aspects of surveillance were discussed, forexample that passive surveillance fails when people feelthreatened by the consequences or when tools and systemsare impractical for the targeted community (e.g., broadcase definitions for AI in areas where poultry deaths arecommon), and thus, that surveillance should be community-basedand customized for each setting. The use ofcommunity-level incentives and disincentives was discussed,and it was agreed that the differences between what may byconsidered incentives and disincentives by the key playersin the human and animal health sectors may not be appreciated.It was agreed that overall, surveillance in human andanimal populations should be better coordinated. Coordinationis working well in Indonesia, where there is activehuman surveillance in areas of animal outbreaks and viceversa. This has, for example, reduced average time tohuman antiviral treatment from 4 to 2 days. It was suggestedthat it would be more sustainable to coordinate AIsurveillance with surveillance for other zoonotic diseases.It was agreed that any coordination requires good communicationbetween the animal and public health sectors,which may vary on the local level and may be influencedpolitically.There was a generalized call for <strong>OIE</strong>, <strong>FAO</strong>, and <strong>WHO</strong>to formalize the sharing of virus samples and associatedinformation for all AIVs. The importance of whole genomesequencing of an appropriate virus subset and ensuringtimely availability of information was also stressed.The problem of information sharing with and amongcountries who may have technological difficulties in ‘‘connecting’’was discussed (as these are often the countries atrisk). It was noted that timely information sharing canalso allow individual countries to decrease their risk ofexposure.4 Human transmission risks and exposuresource (Session 3)The objective of session three was to identify likely modesof transmission and exposure sources for zoonotic infectionwith AIVs. During this session, speakers presented data onpossible modes of seasonal and zoonotic influenza transmission;sources of exposure for human cases of H5N1(including the potential roles of exposure to poultry productsand by-products, of culturally relevant poultry ⁄ humaninteractions, of poultry management systems, of LBMs andof contaminated environments); food safety issues; andevidence to explain the low incidence of H5N1 cases inhumans. The country representatives briefly outlined whatthey considered the successes and challenges of theirnational H5N1 experience, which are also summarizedhere.4.1 Modes of transmission for human infectionwith avian influenza virusesModes of transmissionThe modes of human seasonal influenza transmission havenot been completely elucidated. People shed influenza virusfrom the respiratory tract, and potential modes of transmissioninclude contact spread, aerosol spread, and dropletexposure. Influenza virus survives on hands for 5 minutesbut on other surfaces for 12–48 hours. It was suggestedthat hand hygiene is important to decreasing risk. Viabilityof virus in aerosols depends on initial concentration, temperature,and humidity. Inhalable particles account for