It has been nearly 2 months since the last DEFRA assessment on France's multi-strain avian flu outbreak, and at that time 61 outbreaks of HPAI had been identified involving new strains of H5N1, H5N2, and H5N9. A number of LPAI outbreaks of H5N2 and H5N3 were also reported.
Exactly how these strains came to evolve and emerge in southern France remains largely unknown, although LPAI viruses often circulate wild birds, and on occasion can mutate into HPAI strains - particularly when introduced into poultry operations.
Today DEFRA has published an update, which cites 72 outbreaks of HPAI in southern France, and seven outbreaks of LPAI H5 (N2 and N3). As this outbreak appears to be winding down, The risk level for the UK remains at low, but heightened.
I've only excerpted portions from the Situation Assessment. Follow the link to read the full report.
Updated Outbreak Assessment
Avian Influenza of high pathogenicity (H5N1, H5N2, and H5N9) and low pathogenicity (H5N2, H5N3) in poultry in France
18 February 2016
The eradication programme put in place by the French Authorities is designed to allow current populated farms to continue production until expected point of slaughter and then for strict cleansing and disinfection to take place, followed by a period of several weeks during which the premises must remain empty. Restocking will take place, accompanied by a programme of confirmatory negative testing which will lead to lifting the restriction zone later in the year.
The situation has been compounded by the difficulties in dealing with a complex production system (for fattened ducks) and the presence of strains of avian influenza which do not show overt clinical signs in the majority of poultry. Occasional outbreaks have been detected in galliforme poultry (chickens) through reports of clinical signs, which may signify contact with infected farms or a wider environmental contamination.
The epidemiological studies and restocking / retesting programme will shed more light on which is the likely scenario. Interestingly, the recent epidemiological information from the French Authorities suggests that clinical signs of as much as 15% mortality may occasionally be observed in anseriforme poultry which is important for the success of passive surveillance programmes (Huneau-Salaün et al., 2016). In addition, of 38 outbreaks where epidemiological studies have been completed, 227 links to 157 farms were identified, showing the complexity of the production system. Also, 69% of the links were located in just two departments, Dordogne and Landes, with others in the wider restriction zone (Huneau-Salaün et al., 2016).
A wider surveillance programme for the other non-restricted regions in France will also take place in the coming months, focussing on the duck production industry, but not exclusively so; galliforme poultry will also be included.
(Continue . . .)