With literally hundreds of reports (and follow ups) coming in from all across the EU over the past 90 days, it can be a bit difficult to fully grasp the size of Europe's H5N8 epizootic. More than 650 farms, poultry holdings, and back yard flocks have been infected, and countless wild birds have died across the continent.
The DEFRA map above gives an idea of the scale, but probably doesn't do the outbreak in wild birds justice.This winter's HPAI H5 epizootic (which now includes HPAI H5N5) is unprecedented in size, scope (variety of birds affected), and in its virulence in wild birds, especially waterfowl.
The UK's DEFRA continues to provide us with some of the best summaries of avian flu in both Great Britian, and across EU, and today's report is no exception. Follow the link below for all of the maps and references.
Updated Outbreak Assessment number 10
Highly Pathogenic Avian Influenza H5N8 in the UK and Europe
7 February 2017 Ref: VITT/1200 Avian Influenza in UK & Europe
Since our last update on the 19th January, the zones around the premises in West Wales were merged on 25th January into one restriction zone and were lifted on the 4th February. No onward spread has been found during the patrols in the zone. At the premises in North Yorkshire, the zones were merged on the 30th January and will be lifted on the 9th February. In East Lindsey, with respect to the fourth outbreak, zones will be merged, provided no further cases are detected, on the 11th February.
On the 24th January, clinical signs were reported in pheasants on a large gamebird premises in Wyre District, Lancashire. Birds were not housed or netted and signs included depression, shivering, nervous signs, nystagmus, ataxia, diarrhoea and sudden death. In one field of 5,000 birds, there was an estimated 60% mortality over two days. Testing confirmed H5N8 HPAI in both the field with high mortality and another field with similar number of birds but lower mortality (1-2%).
As a result of the epidemiological investigations, two further premises were identified as having received live birds during the high risk period, and these were restricted and samples tested positive. One had 1200 pheasants (IP7) and the other had 66,000 mixed game birds (IP8). The region has many wild waterfowl close to the infected premises at Morecombe Bay, including a variety of migratory wild waterfowl.
On the 25th January, a turkey farm in East Lindsey, near Boston, reported clinical signs in one of three sheds of young birds (97 days old). High mortality, neurological signs and pyrexia were observed. Samples tested positive on the 26th January and disease was confirmed. All 19,500 birds were culled and primary cleansing and disinfection was completed on the 1st February. Birds were housed.
A GB-wide Prevention Zone remains in place until the end of February 28th, at which time it will be reviewed and the effectiveness of the measures compared to the risk level will be considered. Within the Prevention Zone poultry keepers (including those of small or backyard, non-commercial flocks and captive birds) are required to keep a high level of biosecurity, to keep species separate, feed under a roof with commercial feed, provide clean drinking water and where practicable, to house birds; in addition, the general licence for bird gatherings has been amended, such that gatherings with poultry or captive birds of the anseriforme and galliforme orders are prohibited.
As expected, more findings of wild birds testing positive for the H5N8 HPAI virus have been made. All wild bird positives will be published on a weekly basis on the APHA website at https://www.gov.uk/government/publications/avian-influenza-in-wild-birdswinter-2016-to-2017.
Only exceptional reports in new regions or unusual wild bird findings (ie a change to the disease epidemiology) will be officially reported on an ad hoc basis.
New countries in the EU reporting disease are Portugal in wild birds and Belgium in captive birds. Elsewhere, Uganda has also reported H5N8 HPAI in wild birds and poultry; Egypt has reported disease in poultry; Nigeria has reported more outbreaks in domestic poultry.
In terms of overall numbers, there have been over 650 outbreaks in either commercial, backyard or captive birds in the EU (17 Member States) while a further 5, as well as Switzerland, have reported cases in wild birds only.
It is not possible to give an accurate number of cases in wild birds, because surveillance is targeted at dead birds, but not all may be collected (many will likely be predated) and not all will be tested. Where reports have been made, these are mapped to show the widespread nature of the affected countries. In addition, H5N5 HPAI has been reported on a poultry farm in Germany, but the EURL has sequenced the virus and confirmed that the H5N5 HPAI virus is still essentially an avian virus with no specific increased affinity for humans.
The risk level for the UK is still “HIGH” for an incursion of an infected wild bird, but now that we have wild bird findings, our level of uncertainty has reduced and the geographic area where we expect more findings in wild birds, is wider. The risk to poultry on individual premises is still “LOW TO MEDIUM” dependent on the level of on-farm biosecurity. The widespread location of the positive wild birds suggests that we should consider the whole of the UK is a risk area for wild bird infection but that areas with populations of waterfowl species may carry a greater risk proportionally in terms of risk level for poultry premises.
As a result of the increase in positive findings in wild birds in Europe, we ask that the public use the Defra helpline (Tel: 03459 33 55 77) to report findings of dead wild birds. In particular, any wild ducks, wild geese, swans, gulls or birds of prey and where more than five birds of any species are found dead in the same location.
Further information is available here: https://www.gov.uk/guidance/avian-influenza-bird-flu including updated biosecurity advice for poultry keepers which they should take note of: https://www.gov.uk/guidance/avian-influenza-bird-flu#prevention-zone
The finding in pheasants is unusual and provides further evidence that the clinical signs in these birds are variable but they are susceptible. We continue to consider the risk level is high for further introductions via wild birds, but the risk of entry into poultry farms remains as low to medium depending on the level of biosecurity. Several EU countries will soon have kept birds indoors for up to 12 weeks and therefore birds may be turned out to retain free range status. If they are released onto ranges with environmental contamination then further incursions could occur, and in the current climate and season, virus can remain in the environment for many days.
We would like to remind all poultry keepers that the clinical signs of this virus are variable and will depend on the species, but any suspicion of production drop, increased mortality, sick and depressed birds with a temperature and neurological signs should be reported to their private veterinarian.
We will continue to report on the situation