Outbreaks of highly pathogenic avian influenza (HPAI) have also been reported in Italy. Discover why biosecurity measures can be crucial in limiting the spread of the virus.
THE AVIAN INFLUENZA VIRUS
Avian influenza is a highly contagious viral disease that primarily affects poultry and wild aquatic birds.
A peculiarity of the avian influenza virus is its ability to cause high mortality in some avian species while showing no clinical signs in others, with a marked susceptibility of species even in terms of symptoms and reported lesions.
Avian influenza viruses can be low pathogenic (LPAI) or highly pathogenic (HPAI).
- HPAI
Highly pathogenic avian influenza (HPAI) viruses affect the respiratory and gastrointestinal systems of birds.
They are characterized by extremely high mortality and marked contagiousness.
Historically, outbreaks caused by the highly pathogenic subtype H5 have led to the culling of millions of both wild and farmed birds under stamping out measures to control the spread of the virus.
Signs of HPAI in poultry mainly include sudden death with no opportunity to assess symptoms, or if present, the bird may show severe depression, lethargy, anorexia (lack of appetite), respiratory signs (ocular-nasal secretions, cough, sneezing, wheezing, etc.), decreased egg production, diarrhea. - LPAI
Generally, low pathogenic avian influenza (LPAI) viruses do not cause dramatic symptoms but present mild disease signs: signs similar to those reported for HPAI.
LPAI strains can however mutate into highly pathogenic strains, which is why it is important to contain outbreaks promptly.
Various health and non-health organizations involved in poultry production urge caution and to report any symptoms or signs related to avian influenza.
But why are we discussing avian influenza during a full-blown health emergency caused by the SARS-CoV-2 virus?
Because, more than ever in this historical period, we realize how prevention and the implementation of biosecurity measures are essential to limit the spread of viruses and because since October 2020, several European countries have been affected by cases of highly pathogenic avian influenza (HPAI), caused by the H5 influenza virus subtype.
In Italy, the recorded outbreaks have been limited to family farms in northern Italy (one in the province of Padua, one in the province of Pordenone, and one in the province of Ravenna), and precautionary measures are in place that have previously succeeded in containing outbreaks.
How can poultry farmers prevent the spread of the disease?
As the ongoing pandemic has taught us, to defend ourselves it is essential to know our enemy.
Recognizing clinical signs and reporting them promptly is the first step.
The outbreaks recorded in Italy so far have been identified because the affected groups of animals exhibited classic symptoms, including increased mortality, lethargy, decreased egg production, loss of appetite, and sometimes neurological symptoms.
Alongside close monitoring of animals to recognize signs and symptoms, there is prevention and the implementation of biosecurity measures, with particular attention to the movement of vehicles and personnel entering and leaving, as well as to cleaning and disinfection operations during the sanitary downtime.
Although these procedures are standard and mandatory in intensive farming, where they are imposed by the competent ULLSs based on current regulations, we will briefly outline the general recommendations proposed by the FAO regarding biosecurity measures to be adopted for the containment of highly pathogenic avian influenza (HPAI) outbreaks, which, while standard, are worth remembering.
BIOSECURITY MEASURES
The biosecurity measures to be implemented on farms to control the spread of diseases, with particular reference to HPAI viruses, are carried out through three steps.
SEGREGATION
Essentially, if the virus does not enter a poultry farm, no infection can occur.
No animals, materials, or vehicles related to farming activities should enter or leave a poultry farm unless necessary.
Segregation involves creating physical barriers and controlling them.
Simple measures, such as requiring a change of footwear for everyone crossing the barrier at the farm entrance and limiting vehicle entry, have greatly limited the spread not only of influenza viruses but also of many other diseases.
From the farm gate to the entrance of individual animal housing, this is the first line of defense.
CLEANING
The second step and the most effective for biosecurity is cleaning.
Most viral contamination on physical objects is contained in fecal material or respiratory secretions that adhere to surfaces.
All materials that pass through the aforementioned segregation barriers must be thoroughly cleaned, whether they are coming in or going out.
DISINFECTION
Considered by many as the most important step, in reality, disinfection alone is not fully effective and cannot be separated from the previous steps.
It is well-known that organic residue reduces the effect of the disinfectant, which cannot fully penetrate it; therefore, disinfection without cleaning is less effective.
Not surprisingly, the FAO describes disinfection as the “polishing” phase of biosecurity procedures.
As the ongoing pandemic has taught us, containing the spread of a virus is difficult; prevention is the most efficient form of control.
Tecnozoo invites you to explore its range dedicated to biosecurity in farming.
Among the solutions offered by Tecnozoo, you can find not only highly efficient cleaning products for the farm but also biocidal disinfectants active against highly pathogenic avian influenza viruses, such as VIROCID and VIRKON S.
Tecnozoo also guarantees technical support for the use of all its products, as well as customized consulting for your farm.
SOURCES:
- FAO – “BIOSECURITY FOR HIGHLY PATHOGENIC AVIAN INFLUENZA – Issues and options”
- CDC – HPAI A H5 Virus Background and Clinical Illness
- https://www.efsa.europa.eu/it/topics/topic/avian-influenza
- https://www.izsvenezie.it/temi/malattie-patogeni/influenza-aviaria/situazione-epidemiologica-HPAI/
