The EFSA report on highly pathogenic avian influenza records its unprecedented spread in Europe in summer 2022, while Wageningen University (NL) announces trials of three vaccines.
1) Highly pathogenic avian influenza (HPAI), 2020-2021
Highly pathogenicavian influenza(HPAI), as noted, is a highly contagious infectious disease that affects many species of birds, both wild and domestic (or farmed). And it has the potential to infect other animal species as well (e.g., pigs, equids, dogs). (1)
The European alert on the spread of its H5N8 strain-recorded on 9/30/20 following the EFSA report (European Food Safety Authority) and ECDC (European Center for Disease Prevention and Control) -led the European Commission and several EU member states to adopt interim surveillance and protection measures in 2021. (2)
2) HPAI, 2021-2022
The Highly Pathogenic Avian Influenza (HPAI) outbreak in 2021-2022 had the largest geographical spread observed in Europe to date, in 37 countries, from Svalbard Islands (Norway) to southern Portugal. EFSA reports 2,467 outbreaks in poultry with a total of 47.7 million birds culled, more than 187 outbreaks in captive birds, and 3,573 HPAI virus detections in wild birds.
In the period between 11.6.22 and 9.9.22, 788 HPAI virus detections in poultry (56), captive birds (22) and wild birds (710) were reported in 16 European countries. With widespread mortality of several seabird species due to HPAI A(H5N1) virus along the northwestern European coast. And five times the number of infected premises, on farms, than observed during the same period in 2021 (especially on the Atlantic coast). (3)
3) Avian flu in Europe, current scenario.
Response strategies to this new epidemiological situation ‘include the definition and rapid implementation of appropriate and sustainable HPAI mitigation strategies, such as appropriate biosecurity measures and surveillance strategies for early detection in different poultry production systems .
The viruses currently circulating in Europe belong to cluster 2.3.4.4b with seven genotypes, three of them identified for the first time at this time, identified during the summer. HPAI A(H5) viruses have also been detected in wild mammal species in Europe and North America and have shown genetic markers of replication adaptation in mammals.’ (3)
4) Zoonosis risks
EFSA’s latest report recalls reports from China of five human infections including two from A(H5N6), two from A(H9N2) and one from A(H10N3). The risk of infection in the European Economic Area (27 EU member states, plus Iceland, Liechtenstein and Norway), is assessed as low for the general population and low to medium for occupationally exposed workers.
On 3.10.22 ECDC(European Centre for Disease Prevention and Control) published an update on zoonosis risk preparedness plans, training courses and simulation exercises in a One Health context (4,5). Dwelling on the need for testing for virus infections in patients with respiratory disease and recent exposure to potentially infected animals.
5) Wageningen University, trial of three vaccines.
Wageningen Bioveterinary Research (WBVR)-commissioned by the Dutch Ministry of Agriculture, Nature and Food Quality-has begun an initial trial of three vaccines against avian influenza (H5 virus), made on the basis of different technologies by three pharmaceutical companies. The trial is carried out on laying hens, for three months, in the facilities of the WBVR high containment unit.
The trial aspires to test the effect of vaccines on clinical signs of the disease, but also their effectiveness against the spread of the virus. ‘If vaccinated birds become infected without showing signs of disease‘ – explains avian influenza researcher Nancy Beerens – ‘they could cause a ‘silent’ spread among herds‘.
‘We expect that the new types of vaccines may provide better protection against the spread of the virus than previous vaccines. In addition, it is possible to distinguish between vaccinated and infected animals with specific diagnostic tests’, Nancy Beers continues. Several EU countries have initiated studies on vaccination against avian influenza, and ‘the results of these studies are very important in view of the future European agricultural policy, which may allow vaccination of poultry.’
Dario Dongo
Notes
(1) Dario Dongo, Carmela Mele. Avian flu, alert in Europe. Update. GIFT (Great Italian Food Trade). 18.11.20
(2) Giorgio Perrone. Avian flu, growing contagion on farms. GIFT (Great Italian Food Trade). 2.12.21
(3) EFSA. Avian influenza overview June – September 2022. https://www.efsa.europa.eu/en/efsajournal/pub/7597 EFSA Journal 2022;20(10):7597
(4) European Centre for Disease Prevention and Control. Testing and detection of zoonotic influenza virus infections in humans in the EU/EEA, and occupational safety and health measures for those exposed at work. https://www.ecdc.europa.eu/en/publications-data/zoonotic-influenza-virus-infections-humans-testing-and-detection Stockholm: ECDC; 2022
(5) Dario Dongo. One Health. Animal, human, planetary health and welfare. What can we do? GIFT (Great Italian Food Trade). 2.6.21
(6) Wageningen University. Trial with three vaccines against bird flu. https://www.wur.nl/en/research-results/research-institutes/bioveterinary-research/show-bvr/trial-with-three-vaccines-against-bird-flu.htm. Press release. 29.9.22
Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
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