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I looked up this article to find information on specific poultry symptoms (other than death) and to my amazement, found none. How about some info regarding laying of shell-less eggs, respiratory symptoms, etc.? This disease is wreaking havoc on chickens in some parts of the world, and most of this information is about human medicine, virology, and epidemiology. How about some differential diagnosis info for VVND, etc.?
:Clicking on '''Infection''' in the box at the very top right of the article takes you to the article [[Transmission and infection of H5N1]] where we have a sort section called '''Avian flu in birds''' where we deal with transmission and infection of H5N1 in birds. You can click on the references there and find sources (most online) for further information. Feel free to improve wikipedia with the information you find (just indicate the source - don't worry about correct formating, I'd be happy to do that part). For example, [http://www.ncbi.nlm.nih.gov/entrez/queryd.fcgi?cmd=Retrieve&db=PubMed&list_uids=16191700&dopt=Abstract this article] called "Performance of clinical signs in poultry for the detection of outbreaks during the avian influenza A (H7N7) epidemic in The Netherlands in 2003." says "''The aim of this study was to make an inventory of the clinical signs of high-pathogenicity avian influenza (HPAI), to facilitate the development of an operational syndrome-reporting system (SRS) in The Netherlands as an early warning system for HPAI outbreaks. A total of 537 poultry flocks (240 infected and 297 non-infected) with a clinical suspicion of an infection with HPAI virus were investigated with respect to the clinical signs observed. Standardized reports were analysed with respect to observed clinical signs in the flocks. Various poultry types were distinguished. In infected commercial flocks with egg-producing chickens, the presence of increased mortality, apathy, coughing, reduction in normal vocalization, or pale eggs appeared to be overall the most sensitive indicators to detect a HPAI outbreak, matching a sensitivity of 99% with a specificity of 23%. In infected turkey flocks, the presence of apathy, decreased growth performance, reduction of normal vocalization, swollen sinuses, yawning, huddling, mucosal production from the beak, or lying down with an extended neck appeared to be overall the most sensitive indicators to detect a HPAI outbreak, matching a sensitivity of 100% with a specificity of 79%. In infected backyard/hobby flocks, increased mortality or swollen head appeared to be overall the most sensitive indicators of a HPAI outbreak, matching a sensitivity of 100% with a specificity of 26%. These results indicate that there is a solid basis for the choice of using increased mortality in the operational SRS in The Netherlands as an early warning system for HPAI outbreaks. The presence of apathy, specifically for turkeys, should be added to the SRS as an indicator''". You will note that it was a study of HPAI due to [[H7N7]] and you asked about HPAI due to [[H7N7H5N1]]. The disease HPAI manifests itself mostly the same in poultry whether it is from one stain or another. Timm C. Harder and Ortrud Werner say in [http://www.influenzareport.com/ir/ai.htm Avian Influenza of Influenza Report] "''Following an incubation period of usually a few days (but rarely up to 21 days), depending upon the characteristics of the isolate, the dose of inoculum, the species, and age of the bird, the clinical presentation of avian influenza in birds is variable and symptoms are fairly unspecific (Elbers 2005). Therefore, a diagnosis solely based on the clinical presentation is impossible. The symptoms following infection with low pathogenic AIV may be as discrete as ruffled feathers, transient reductions in egg production or weight loss combined with a slight respiratory disease (Capua and Mutinelli 2001). Some LP strains such as certain Asian H9N2 lineages, adapted to efficient replication in poultry, may cause more prominent signs and also significant mortality (Bano 2003, Li 2005). In its highly pathogenic form, the illness in chickens and turkeys is characterised by a sudden onset of severe symptoms and a mortality that can approach 100 % within 48 hours (Swayne and Suarez 2000). Spread within an affected flock depends on the form of rearing: in herds which are litter-reared and where direct contact and mixing of animals is possible, spread of the infection is faster than in caged holdings but would still require several days for complete contagion (Capua 2000). Often, only a section of a stable is affected. Many birds die without premonitory signs so that sometimes poisoning is suspected in the beginning (Nakatami 2005). It is worth noting, that a particular HPAI virus isolate may provoke severe disease in one avian species but not in another: in live poultry markets in Hong Kong prior to a complete depopulation in 1997, 20 % of the chickens but only 2.5 % of ducks and geese harboured H5N1 HPAIV while all other galliforme, passerine and psittacine species tested virus-negative and only the chickens actually showed clinical disease (Shortridge 1998). In industrialised poultry holdings, a sharp rise followed by a progressive decline in water and food consumption can signal the presence of a systemic disease in a flock. In laying flocks, a cessation of egg production is apparent. Individual birds affected by HPAI often reveal little more than severe apathy and immobility (Kwon 2005). Oedema, visible at feather-free parts of the head, cyanosis of comb, wattles and legs, greenish diarrhoea and laboured breathing may be inconsistently present. In layers, soft-shelled eggs are seen initially, but any laying activities cease rapidly with progression of the disease (Elbers 2005). Nervous symptoms including tremor, unusual postures (torticollis), and problems with co-ordination (ataxia) dominate the picture in less vulnerable species such as ducks, geese, and ratites (Kwon 2005). During an outbreak of HPAI in Saxonia, Germany, in 1979, geese compulsively swimming in narrow circles on a pond were among the first conspicuous signs leading to a preliminary suspicion of HPAI.''". [[User:WAS 4.250|WAS 4.250]] 17:05, 11 June 2007 (UTC)
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