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Showing posts with the label avian influenza

H5 HPAI outbreaks in poultry flocks in the USA

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Since December 2014, the United States Department of Agriculture (USDA) has confirmed H5 Highly Pathogenic Avian Influenza (HPAI) in commercial and backyard poultry flocks in the United States. At least 142 separate incidents have been detected through May 7, 2015; most are the H5N2 virus.[1] According to USDA, more than 29 million birds have been infected including chickens, ducks, pheasants, and turkeys mostly in commercial poultry flocks. Chickens represent about 81% of all infected poultry followed by turkeys with 18% of the total. In addition to the poultry flock infections in the United States, at least 60 incidents of detection of H5 HPAI in wild birds have also been reported since early December 2014 from the 13 states [2] shown in the map below. H5 HPAI has been detected in poultry flocks in 13 states as well. However, there is no on-to-one correspondence between the states reporting wild bird infections and those with poultry flock infections as show on the map below. Base...

Confusion surrounds the number of H5N1 cases in Egypt

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The most recent, cumulative World Health Organization (WHO) table of human H5N1 cases was published on March 3, 2015.[1] This table notes a total of 88 human H5N1 cases in Egypt through March 3, 2015. As I noted previously [2] the tabulation of counts based on the line list of cases published in the monthly risk summaries only totals 82 cases for Egypt in 2015 based on onset dates in reports of 2015. To understand the confusion in the Egyptian case counts in the WHO table, it is necessary to consider the 2014 totals provided by WHO. The current WHO cumulative table reports 46 cases of H5N1 in 2014 with 31 cases from Egypt.[1] However, individual enumeration of WHO-confirmed H5N1 cases based on line lists in the monthly risk assessments shows a total of 52 H5N1 cases in 2014 (based on onset dates), with 37 of these reported from Egypt.[3] The table below identifies the distribution of WHO-confirmed H5N1 from Egypt by each of the monthly summaries for 2014 through the most recent asse...

The CDC is Watching for Human Avian Influenza Infections

So far, North America has been lucky. Community acquired infections of avian   influenza have not yet occurred, although an imported case of H5N1 was identified in Alberta Canada in 2013 and two imported cases of H7N9, a husband and wife, were reported from British Columbia in just this past week. Because of recent outbreak of highly pathogenic avian influenza (H5 subtypes) in wild birds and domestic flocks in North America, the Center for Disease Control has issues guidance for health care workers for identifying and testing patients with potential avian influenza infections. As of January 31, 2015, no H5 subtype human avian influenza infections have been recorded from these outbreaks which have been reported from six western states along the Pacific Flyway (Washington, Oregon, Idaho, Nevada, Utah, and California ). ( link ) CDC document: Interim Guidance on Testing, Specimen Collection, and Processing for Patients with Suspected Infection with Novel Influenza A Viruses with the P...

Human Cases of Avian Influenza Infections in 2014

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In 2014, 366 human cases of avian influenza infection from four subtypes, A(H7N9), A(H5N1), A(H5N6) and A(H10N8) were reported from 7 countries, China, Egypt, Taiwan, Malaysia, Cambodia, Indonesia, and Vietnam. The case-fatality risk ranged from possibly as low as .22 to as high as .67 among these subtypes in 2014. There is no evidence among any of these subtypes of sustained human-to-human transmission. Influenza viruses that easily circulate among human populations are referred to as seasonal influenza viruses and can cause severe illness in 3 to 5 million individuals annually.[1] Avian influenza Type A viruses that cause infection in birds are referred to as avian influenza viruses. These viruses occur naturally among wild birds worldwide and can infect domestic poultry and other bird and animal species.[2] These avian influenza viruses circulating in bird populations do not usually infect humans. However, sometimes humans can become infected with avian influenza subtypes which hav...