Wednesday, September 28, 2016

DEFRA: Update On HPAI & LPAI Avian Flu Outbreaks in France














#11,775


Two months ago in DEFRA: Update On HPAI Outbreaks In France
we looked at the UK's Department of  Environment, Food and Rural Affairs mid-summer update on a prolonged, and multi-subtype string of avian flu outbreaks in Southern France which began last November. 

These outbreaks involved new strains of HPAI H5N1, H5N2, and H5N9, along with LPAI H5N2 and H5N3.  All are reported to be of European lineage, and unrelated to the more dangerous Eurasian H5N1 virus.

Since then we've only seen a handful of new detection's (see France: Another HPAI H5 Outbreak In Aveyron & FAO LPAI 15/09/2016: France - Influenza - Avian), raising hopes that the threat may be winding down.

The summer, however, is typically a time where avian flu outbreaks decline. So with the onset of fall, reminders are going out to all poultry producers on the importance of maintaining good biosecurity and promptly reporting any signs of infection.

I've excerpted the majority of the report, but follow the link to read it in its entirety. 

Updated Outbreak Assessment Avian Influenza (H5N1, H5N2, H5N3 and H5N9) in poultry in France

26 September 2016
Ref: VITT/1200 HPAI /LPAI 


 Disease Report

Since the last update on the 20th July, a small number of outbreaks in poultry have been reported as a result of increased surveillance in South West France (see map for outbreaks reported since the fallow period began). To date there have been 81 outbreaks of HPAI H5 (N1, N2 and N9) and nineteen outbreaks of LPAI H5 (N2 and N3) which have been reported to the EU Animal Disease Notification System since the disease was first confirmed in November 2015. The latest results are an increase of two HPAI and three LPAI outbreaks on July’s figures (OIE, 2016; Huneau-Salaün et al., 2016). Disease control measures in line with EU rules have been put in place around each infected premises including culling all poultry present.

The restriction zone (under an amendment to Implementing Decision 2015/2460/EU) remained in place until the 15th September but has now been lifted on the basis of the French eradication plan and level of surveillance carried out in the last few weeks.


Situation Assessment

France has been carrying out surveillance in the Restriction Zone and reporting the results of this testing, in order to lift the zone this September. For more information see the French Epidemiology platform at http://www.plateforme-esa.fr/
According to Huneau-Salaün et al (2016) the surveillance entailed testing to detect 1% prevalence, with 99% confidence in poultry holdings with ducks and geese destined for production. This included young birds, fattening birds and the gavage units. For the young birds, up to 3-4 weeks of age, virological testing only was carried out on statistical samples. For fattening units, serological testing was done, with follow-up PCRs if positive results are found. At the gavage holdings, for birds destined for slaughter, statistical sampling by serology and PCR was undertaken.
The same prevalence level was used for the Galliform poultry which were located close to holdings for ducks and geese (as these are considered at higher risk). Samples were only taken where clinical suspicion was reported following veterinary clinical inspection. The majority of surveillance has now been completed. No outbreaks were detected in the gavage units or in the Galliform units.

Since surveillance began at the beginning of the year, 96 serology positive (virus negative) breeding premises have been detected, of which 19 were in the free zone (and were depopulated) and 77 were in the restriction zone. These will be under restriction until March 2017 and tested regularly, although 15 have pre-emptively culled.

In total, prior to the disinfection and fallow period, 93 outbreaks were detected. Since that period (on the 15th July) there have been just seven detections of HPAI or LPAI. In terms of premises visited or tested, there were 425 Galliform holdings, 287 samples taken at slaughter houses, 231 at gavage units and 421 at holdings for young and fattening birds (pre-gavage). It is the latter group where there are still some seropositive birds and these will remain restricted and retested until March 2017.

As additional evidence about lifting the zones, surveillance has been carried out in wild birds in the restriction zone, and commensal wild birds (mainly passerines) around the outbreaks (Anses, 2016). During the programme, 32 wild species were tested (600 samples); over 100 droppings from heronries (migratory Ibis) close to outbreaks; 10 samples from raptors in the restriction zone; 23 samples from crows from an area close to the outbreaks. All tested negative by PCR. The conclusions of the study were that if virus has spread from the poultry into wild birds, the prevalence of infection would be very low; that it would be unlikely the viruses were maintained in wild birds; if wild birds had been infected, the prevalence would have been very low and therefore unlikely to be a source of contamination when the farms were restocked.

Conclusion

Any new outbreaks detected in France will be treated as any other outbreaks of avian influenza in poultry in accordance with EU rules, but the strict sanitary measures which were put in place across the wide restriction zone to allow C&D to take place, will now be lifted as a result of the surveillance results.

We will continue to monitor the situation as usual. We would like to remind all poultry keepers to maintain high standards of biosecurity, remain vigilant and report any suspect clinical signs promptly and in addition using the testing to exclude scheme for avian notifiable disease where appropriate for early safeguard. For more information, please see
www.defra.gov.uk/ahvla-en/disease-control/nad

The risk level for the UK remains at low, but heightened.