FLI: Risk Assessment Of HPAI H5 Affecting Germany This Fall & Winter

 

Recent Avian Flu Outbreaks In Russia & Kazakhstan

#15,486

Another European state agency - this time Germany's FLI (the Friedrich-Loeffler-Institut) - has weighed in on the risk of seeing the return of HPAI H5 in Europe this fall, following numerous reports of outbreaks over the past couple of months in Russia and Kazakhstan (see Kazakhstan MOA: Avian Epizootic Reported In 7 Northern Districts).

This warning comes on the heels of last week's report from ECDC & EFSA Warning Of Avian Flu Risk To Europe and concerns raised in early September by DEFRA. 

Although avian flu activity has been on the decline in Europe since their record-breaking HPAI H5 outbreak ended in the spring of 2017, these recent reports are reminiscent of the run-up to that 2016-2017 epizootic (see OIE: Russia - HPAI H5 In Wild & Migratory Birds), which saw a highly virulent reassorted HPAI H5N8 virus arrive in Europe that fall.

Since we've recently trod this ground at some length (see here, here, and here), I'll simply post the (translated) press release, link, and some  (translated) excerpts from today's report. 

 

New risk assessment for the occurrence of avian influenza (“bird flu”) in Germany - high risk of entry from wild birds during autumn bird migration

05/10/2020 Press releases


Riems Island, October 2nd, 2020. The Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health ( FLI ), presents a new risk assessment for the entry of highly pathogenic avian influenza ( HPAI ; avian influenza) of subtype H5 by Wilvögel to Germany. 

Since July 2020, a number of identifications of influenza viruses of the subtype H5 (N8) in wild birds and poultry holdings have been reported from Russia and Kazakhstan. Similar series of outbreaks in the same region were observed in 2005 ( HPAI H5N1) and 2016 ( HPAIH5N8) was observed, which was then followed by epidemic spread of the pathogen in Eastern and Central Europe. 

The new evidence lies on migratory routes of migrating wild birds from the breeding area in Siberia to Eastern Europe. As the bird migration will peak in the next few weeks, the FLI recommends increased vigilance against dead birds found in the wild and a review of the biosecurity measures in poultry holdings. "Prevention is always better to have to perform, rather than later to combat animal diseases," said the President of FLI , Prof . Thomas C. Mettenleiter.

 

Risk Assessment to the Occurrence of HPAIV H5 in Germany 

A series of HPAI H5 outbreaks in poultry and wild birds have been reported from Russia and Kazakhstan since the end of July 2020. The region lies on the route of migrating waterfowl that migrate to Europe in autumn. In the years 2005/2006 and 2016/2017, similar series of outbreaks in the same region preceded a subsequent extensive event in Europe. Should this pattern be repeated, the renewed entry of HPAIV H5 into Europe by water birds must be expected in autumn or winter. The risk of HPAIV entering Europe and Germany in the course of autumn or winter is accordingly classified as high. Monitoring measures with regard to dead or sick wild birds should be intensified immediately and the biosafety in the poultry farms should be checked and, if necessary, optimized.

Assessment of the situation 

The HPAIV H5 event in the lake area in the southern foothills of western Siberia and adjacent northern Kazakhstan is worrying because it coincides in time and space with the autumn migration of migrating waterfowl, which are currently gathering there in large numbers (e.g. bless geese, song swans). Depending on climatic conditions, the withdrawal of duck and geese species, which wintering quarters in Eastern Europe.

A sudden cold snap can accelerate the south-westerly bird migration. In many parts of Germany, well-suited resting and hibernation areas for a large number of waterfowl are mainly from Scandinavia, the Baltic States but also from Risk assessment of the occurrence of HPAIV H5 in Germany northern and western Russia, some even from Siberia (including singswana, dwarf swan, ringed goose, row duck, table duck, goose-saw).

The late summer or autumnal appearance of migratory birds in Germany is staggered in a species-specific manner. The migratory bird species, which were already used in July and

August from distances of more than 1,000 km, belong almost exclusively to the group of Limicoles (waders). Ducks do not reach Germany until september (reasons such as:  the stock duck) and in October (diving seofes such as the row pension). Nordic wild geese (blässgans, Seed goose) and swans (sing-swan, dwarf swan) arrive for the first time between mid-October and mid-November, depending on their geographical origin.

The autumnal bird migration in Germany does not run in every year identical, but can be different depending on various factors, especially weather-related. In many waterbird species, so-called cold escapes are part of the normal tensile behaviour. In this way, highlights of the autumn procession of ducks, geese and swans can be weather conditions are expected to vary in time in the months of October and November. 

Various studies have shown that cold snaps in 2005 and 2016 had facilitated the entry and spread of HPAIV H5 from Asia to the west to Europe. Low temperatures in autumn and winter stabilize the infectivity of influenza viruses in the environment. If the collect and mix waterfowl in large numbers, virus transmissions between wild birds and thus favours the spread of viruses. A comprehensive study of wild waterfowl is as a rule, the actual spread of HPAI H5 viruses is only possible from sporadic finds, cannot be assessed in its entirety. 

Assessment of the risk and recommendations

The current HPAIV H5 outbreaks, particularly in western Russia and northern Kazakhstan could indicate a possible new entry of HPAIV H5N8 to Europe in connection with the beginning of the autumn migration of water birds. A few months before the occurrence of 2005/2006 and 2016/2017 HPAI H5 epidemics in Europe were outbreaks of the same virus in between July and September the above Regions of Russia have been reported. When HPAIV H5 follows the same paths over wild birds as in the past, in the next few months there will be more cases of wild birds in Eastern Europe to be expected. From there, depending on the climatic conditions, the virus could move westwards Expand Central and Southern Europe.

Bird migration (including waterfowl) is currently in full swing and the density of bird populations in roosting areas will increase in the coming weeks. These conditions favor virus transmission and spread.

Therefore, the risk of HPAIV H5 entering Germany during the autumn migration or winter cold escapes by migrating waterfowl is classified as high.