With the cold season and the migration of wild birds, the threat of bird flu returns. Already the alert is high and the infection has already affected several farms in Italy, as well as other European countries and Asia. In China, however, there is a species jump.
Avian flu, the virus in birds
Avian influenza-Avian Influence (AI)-is a highly contagious viral disease that predominantly affects poultry and wild waterfowl.
Poultry infected with low pathogenicity virus (LPAI type) may be asymptomatic or have only mild symptoms. Infections caused by the highly pathogenic virus (HPAI type), on the other hand, can be lethal.
Timely and radical measures
However, both types of viruses can spread rapidly through flocks of birds. They must therefore be contained promptly, warns EFSA(European Food Safety Authority). (1)
Upon detection of an outbreak, in fact, procedures for abatement, cleaning and disinfection of affected areas and establishment of protection and surveillance zones are immediately triggered. All control measures are implemented as required by Delegated Regulation 2020/687.
Mass abatement
The practice of mass culling results in significant economic damage, some of which is compensated to poultry farmers. However, it remains unavoidable because in most cases the farms are intensive, thus high animal density.
Forced into constant and very close contact, chickens or turkeys become infected with extreme speed, leading to outbreaks that can affect hundreds of thousands within days.
Italy’s first case in Ferrara
The first national case of avian influenza was recorded about mid-October 2021 at a turkey farm in the province of Ferrara.
Veterinarians and specialists at the National Reference Center of the Experimental Zooprophylactic Institute of the Venezie detected the presence of the highly pathogenic virus (HPAI) in 82 percent of the animals tested.
Outbreaks in Veneto
Another case emerged on Oct. 18.10.21, when the National Reference Center for Avian Influenza and Newcastle Disease confirmed a positive finding for influenza virus type A, subtype H5N1 highly pathogenic (HPAI), on a broiler turkey farm in Ronco all’Adige, Verona province.
At the time of confirmation, there were about 13,000 birds on the farm. Given the presence of a game preserve in the vicinity of the infected farm, the most likely route of virus entry can be found in indirect contact with wild birdlife.
Spotty contagion
In the following days positivity for highly pathogenic influenza virus has been confirmed on samples taken from two other broiler turkey farms located close to the surveillance zone established following the detection of the first outbreaks and more precisely in the municipalities of San Bonifacio and Nogara, both in the province of Verona.
Phylogenetic analysis performed on the viruses identified in the first 4 different HPAI H5N1 outbreaks in Ronco all’Adige (VR) showed that they are very closely related viruses genetically which suggests a single primary introduction, presumably from wild birds, followed by dissemination to other flocks.
The Veneto Region Ordinance
The Veneto Region immediately issued measures to contain and manage the emergency.
Throughout the region, with the exception of the restriction zones established as a result of HPAI outbreak, he ordered an extraordinary monitoring of meat turkey farms. (2)
Most affected are turkeys
According to epidemiological data from the Venezie Experimental Zooprophylactic Institute, avian influenza has hit industrial turkey farms hardest. The animals involved are about
– 350,000 turkeys, distributed in 16 plants, all but one in the Veneto Region,
– 200,000 laying hens,
– 100 thousand broiler chickens (broilers).
The map of contagion
The Istituto Zooprofilattico Sperimentale delle Venezie active in Veneto, Friuli Venezia Giulia and the autonomous provinces of Trento and Bolzano periodically updates a map, with a census of all detected avian influenza outbreaks.
The most recent map, shown below, indicates cases found on industrial and rural farms, with reports of wildlife as well.
The outbreaks, as can be seen, are mainly located in the province of Verona, with a few cases in Brescia and Cremona. (3)
The Ministry of Health’s guidance
In turn, the Ministry of Health has issued guidance on prevention and containment activities to be carried out on farms.
Required procedures include reporting to AUSLs any abnormalities in the number of animal deaths and conducting random testing.
In areas most at risk, poultry should also be kept under cover and isolated until transported to slaughter areas.
Blocking exports to Israel
In addition, by circular dated 4.11.21, the Ministry of Health released information on the establishment by Israeli authorities of a blockade of imports from Italy of poultry, poultry genetic material, table eggs and captive birds.
Specifically, the entry into Israel of table eggs shipped from Italy after 4.10.2021 is prohibited.
Rome, swans at Villa Pamphili hit
Other cases nationwide were detected in Rome. The first in a commercial farm of about 250 laying hens affected by the same highly pathogenic strain that has affected farms in northern Italy.
Peculiar episode also occurred in the capital, where a swan died of avian influenza inside a pond at Villa Pamphili, as confirmed on 26.11.21 by tests conducted by the Istituto Zooprofilatico Sperimentale di Roma.
Chickens asphyxiated and positive for the virus
An additional case of infection finally emerged in Fagagna, in the province of Udine. Local press reports that the theft of diesel fuel on a farm prevented the ventilation of the sheds through the appropriate machinery causing the death of more than 15 thousand chickens.
As per practice, some carcasses were sent to the Zooprophylactic Institute for testing, and they tested positive for avian influenza.
The situation in Europe
In recent months, the virus has affected 17 countries in Europe. France, the Czech Republic, Finland and Sweden reported significant losses in herds mowed down by the highly pathogenic disease.
However, England is the most affected area in Europe, with about 50 poultry farms affected by the highly pathogenic virus. Agglomerations of wild birds and 20 flocks of captive-bred ornamental birds were also found to be infected in the same area.
France, poultry and poultry in lockdown
Drastic measures have been taken in France, where Agriculture Minister Julien Denormandie has instituted a lockdown of sorts for poultry and birds. Fairs, the introduction of game into the wild and the use of bait, and the entry of competition pigeons into the country are prohibited until March 31. Instead, in zoos and for birds that cannot be confined or netted, vaccination becomes mandatory.
This is hoped to avoid the phenomenon of last winter, when some 500 points of contamination occurred on farms in France, mainly in the southwest of the country, the production area of the infamous foie gras, and the health emergency led to the slaughter of 3.5 million animals, mainly ducks.
Worrying scenario
According to experts, the situation in Europe is under control, but worrisome.
Europe is cyclically hit by vigorous migratory currents of wild birds from the extreme latitudes of Russia. The continued circulation of ‘imported’ viruses could promote the persistence of the microorganism and generate variants or even new viruses. Events that pave the way for new variants of the primitive disease or, worse, lead to the so-called species jump (from animal to human). (5)
Risk of infection for humans
At present, ‘It is highly unlikely that there could be a passage of the virus to humans,’ says Maurizio Ferri, a veterinary doctor for the Asl of Pescara and head of the scientific coordination of the Italian Society of Preventive Veterinary Medicine.
The real issue now is to circumscribe the risk through proper management of infected animals to be killed and their carcasses.
In order for the avian flu ‘become dangerous there must be conditions for transmissibility between birds and humans. For example, a similar condition was found in some small rural farms in Asia where it happened that the virus replicated in humans, but we are talking about close cohabitation between humans and infected birds‘, Ferri explains.
The leap of species in China
Such baleful conditions have manifested themselves in China, where avian influenza has made the leap of species.
The Macau Health Bureau (SSM) has confirmed a case of H5N6 avian influenza in a 60-year-old farmer in Changde a town in Hunan, southern China.
Contact with infected poultry
The woman is hospitalized in critical condition. The infection is attributed to the woman’s contact with dead poultry. Authorities urge the public to comply with bio-safety protocols and avoid contact with poultry droppings and dead poultry.
‘Since April 2014’
, reports a SSM note, ‘cases of H5N6 avian influenza have been confirmed in Sichuan, Guangdong, Yunnan, Hubei, Hunan, Anhui, Guangxi Zhuang Autonomous Region, and Jiangsu.’ (6)
George Perrone
Notes
(1) See EFSA, Avian Influenza. https://www.efsa.europa.eu/it/topics/topic/avian-influenza
(2) Veneto Region. Avian influenza – activities to strengthen biosecurity and surveillance measures on the regional territory, except in the restriction zones for HPAI. Note dated 20.10.21 https://resolveveneto.it/wp-content/uploads/2021/06/Monitoraggio-straordinario-TC-Veneto_201021.pdf
(3) SEE https://www.izsvenezie.it/temi/malattie-patogeni/influenza-aviaria/situazione-epidemiologica-hpai/
(4) See Ministry of Health DGSAF 0025571-P- 04/11/2021
(5) Giancarlo Belluzzi, Migrators and Avian Influenza: a recurrent threat. Agricultural Consultancy, 10/26/21. https://www.linkedin.com/feed/update/urn:li:activity:6860109839423594496/, https://consulenzaagricola.it/approfondimenti/597-approfondimenti-varie/15923-migratori-ed-influenza-aviaria-una-minaccia-ricorrente
(6) Macau reports new human case of H5N6 bird flu in Hunan, The Poultry Site, 20.11.21. https://www.thepoultrysite.com/news/2021/10/macau-reports-new-human-case-of-h5n6-bird-flu-in-hunan
V. Macau Health Bureau (SSM). Communiqué dated 1.11.21 https://www.ssm.gov.mo/portal/
Jurist and specializing in food law and safety.
