Influenza aviaria

Respiratory protection and avian influenza

Avian flu is a viral disease affecting wild and domestic birds that, once infected, eliminate the virus in large quantities through stools and respiratory secretions; Avian influenza viruses usually do not directly infect man. The virus can survive in tissues and stools of infected animals for long periods, especially at low temperatures (over 4 days at 22 ° C and more than 30 days at 0 ° C) and can remain indefinitely in frozen material. On the contrary, it is sensitive to heat action (at least 70 ° C) and is completely destroyed during the cooking process of foods. At present, its transmission has been demonstrated only by animals infected with humans and is related to close contact with live infected animals and / or their lesions, while there is no evidence of transmission from man to man or from transmission through the consumption of poultry or eggs. In order to prevent the introduction of the disease in the Community, following its onset in many Asian countries, the European Commission and the Ministry of Health have provided: – the ban on imports of poultry meat and derived products from Thailand (Thailand was the only country among those affected by the epidemic that was allowed to export poultry meat to the European Community) – the ban on imports of ornamental birds and aviary from all countries affected by the epidemic. It should also be noted that none of the Asian countries affected by the epidemic has ever been authorized to export live poultry of zootechnical interest in the European Union.

Frequent questions

What is bird flu and how can its symptoms be recognized?

It is a viral infection that may affect wild and domestic birds like chickens and turkeys, causing it to die. It is caused by type A influenza viruses that can infect other animals such as pigs, horses, dolphins, whales and humans. After a period of incubation of about seven days, the symptoms may range from flu-like illness of a more severe form, characterized by eye infections, serious lung problems, which may endanger life.

What are influenza viruses?

Influenza viruses are classified into three types: A, B and C, the latter with poor epidemiological relief for man, as it rarely causes sporadic cases and epidemics. Type A influenza viruses can be subdivided into subtypes based on their surface proteins - haemagglutinin (HA) and neuraminidase (NA). Are known 15 subtypes. While all subtypes can circulate among birds, it is known that only three subtypes of H (H1, H2 and H3) antigens and two subtypes of N (N1 and N2) antigens circulate, or circulated, even in humans. Type A influenza virus can cause severe infections in some animal species, including birds, pigs, horses, dolphins and whales. The influenza virus that infects birds is called "avian influenza virus". Birds are an important species since all known influenza A subtypes have spread among wild birds and are therefore considered to be the natural host of influenza A. Viruses of avian influenza usually do not directly infect men nor are they usually transmitted from person to person.

How does man get infected?

Usually avian influenza viruses do not infect men; however, have been reported reports of human infections. Man may be infected with the avian influenza virus following direct contact with infected (live or dead) animals and / or their excretions (feces, urine, saliva and respiratory secretions), while there is no scientific evidence of transmission through the consumption of poultry or eggs after careful cooking (70 ° C).

How long can this virus survive in the environment?

Generally, the "life" of each virus depends on various environmental factors, such as temperature and humidity, and varies greatly from viruses to viruses; in optimum conditions, for example in very humid and fresh environments, the avian influenza virus may survive for a few weeks.

How is avian influenza transmitted and how can it be restricted?

Like any other type of virus: by contact with saliva, nasal secretions and stools or by inhalation at moments when the virus may be dispersed in the air. In most cases, infection is caused by contact with infected poultry (since most of the birds we are dealing with fall into this category) or contaminated surfaces. Starting from the assumption that we should avoid contact with infected birds or contaminated surfaces, we can try to prevent the danger by paying attention to the hygiene of the hands and the environments in which we live.

Is there a potential risk that the avian influenza virus, H5N1, may become responsible for a flu pandemic?

All flu viruses are mutated. The avian influenza virus, the H5N1, may also undergo a mutation that can capture the ability to infect people and spread from person to person.

Can the transmission of avian influenza occur from person to person?

To date, vigilance agencies reported only a very small percentage of personal contact infections, still feeling this event highly unlikely in current conditions.

What type of personal protective device (PPE) should you wear for those who are in contact with the disease?

Operators who usually have to deal with infected birds should wear at least one certified respirator according to EN149 class FFP2 (50630; 50631; 50641) or higher (50651). Of course, in addition to the masks, wear disposable gloves, protective clothing, protective goggles so as to exclude all possibility of contagion. Disposable DPIs must be disposed of in accordance with current regulations, while reusable DPI must be cleaned and disinfected. Last but not least, after removing the DPIs, it is necessary to disinfect your hands very well.

Patients with avian influenza should wear a surgical mask?

Anyone suspected of having contracted the infection should be isolated and wearing a surgical mask so that it does not contribute to the spread of airborne contamination.

What kind of personal protective device (DPI) should wear healthcare workers?

According to the Centers for Disease Control and Prevention (CDC) and the WHO (World Health Organization) of the United States, due to uncertainty about how the disease is transmitted, the precautions to be taken should be identical to those adopted in case of Acute Severe Respiratory Syndrome (SARS). Therefore gloves, protective clothing, eye protection and respiratory protection certified N-95 NIOSH (US standard) or EN143 P2 - EN149 FFP2 (European standard). The ICEA models falling under this category are: 50630; 50631; 50641. Disposable PPE should be disposed of in accordance with current regulations, while reusable DPIs should be cleaned and disinfected. Last but not least, after removing the DPIs, it is necessary to disinfect your hands very well.

What's the difference between a certified respirator like DPI and a surgical mask?

Respirators that have been certified as DPI are designed to help reduce exposure to airborne particles, thus preventing entry into the body. The primary purpose of a surgical mask is to prevent organic particles from expelling the helmet from spreading into the environment. There are medical masks that seem to seal the face tightly but are not actually designed to protect the user from the risks that are dispersed in the air. Therefore, they should not be worn as replacements for approved respirators as DPI (always be careful about this a respirator shall be affixed to a CE marking of the 3r class as follows: CE + Certification Number).

Do normal respirators protect against bacteria and viruses?

Respirators are designed to reduce the exposure of those who wear them to the risks of chemical or biological agents dispersed in the air. Organic agents are particles that can be filtered from dust filters with the same efficiency as non-biological particles that have the same physical characteristics (size, shape, etc.). Unlike most of the particles present in industrial environments, no exposure limit has been set for biological agents, so wearing a respirator will reduce the exposure to avian influenza virus, but will not eliminate the risk of infection 'bird flu.

Can disposable respirators be exchanged between people?

Absolutely not. Disposable respirators should never be swapped.

Is it possible to reuse the respirator after use?

Disposable respirators must not and can not be cleaned or disinfected for later reuse: it is necessary to remove the respirator immediately after use according to the regulations in force. There are some reusable respirators on the market that can be disinfected with a delicate solution of water and bleach (0.1% sodium hypochlorite).

How important is the adherence of the respirator?

Adherence is very important: if you wear a respirator that does not have a perfect adherence to the face, particles suspended in the air can penetrate between the face and face mask and reach the breathing area. Therefore, be sure to check the air tightness before entering a contaminated environment and take some small steps: keep your face well shaved so that the beard, long mustache and basette do not create a thicker face and facial, and decrease the efficiency of the respirator.

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