Avian influenza is a fruitful subject of medical-scientific investigation, as well as a source of concern among sector authorities. In this article, we will delve into some aspects related to avian flu, focusing on the risks to humans and prevention methods.
What avian influenza is
Known for its detrimental impact on the poultry sector, avian influenza is a zoonosis caused by certain type A influenza viruses. These primarily infect birds, but can occasionally also infect humans, causing significant symptoms affecting the respiratory system (and beyond). If not monitored and, above all, avoided, avian influenza could generate a new pandemic.
Most widespread viral subtypes and main differences
In general, influenza A viruses are divided into subtypes based on two structural components: hemagglutinin (H) and neuraminidase (N). Considering the first component, the subtypes responsible for avian influenza are mostly classified as H5 and H7, although H9 subtype viruses also occur. Taking the second component into account as well, there are two well-documented subtypes in the literature, known as H5N1 and H7N9.
With regard to pathogenicity in birds, avian influenza subtypes are grouped into low pathogenicity viruses (LPAI) and high pathogenicity viruses (HPAI). Pathogens in the first group, specifically, cause mild disease, while those in the second group are associated with more severe and systemic symptoms (e.g., respiratory and gastrointestinal problems, hemorrhages, etc.). Returning to the two subtypes mentioned earlier, H5N1 and H7N9, they fall among the highly pathogenic viruses and are known to have infected humans. H9 subtypes, on the other hand, are mainly associated with mild diseases and are classified as LPAI.
How and when the species jump to humans occurs
Species jump, or spillover, is defined as the acquired ability of an animal virus to cause disease and spread in a non-usual host species. This phenomenon is due to the tendency of viruses to randomly mutate their genome, developing new infectious abilities. In spillover to humans, the virus becomes capable of attacking human cells and exploiting them to multiply. Importantly, the species jump is favored by prolonged proximity between the two different species.
Transmission and risk factors
The modes of transmission of avian influenza are a dominant aspect of viral dynamics, and understanding the mechanisms is the first step to acting in prevention. Let’s see what this involves.
Contact with birds and contaminated surfaces: typical scenarios
Among birds, avian influenza viruses are transmitted mainly via the oro-fecal route, but not only, as we will see. Wild aquatic birds (e.g., ducks, geese, etc.) act as a natural “reservoir,” harboring these pathogens without, for the most part, developing disease. Transmission to farmed poultry species (e.g., chickens, turkeys), which tend to develop infection symptoms, occurs through contaminated water and environments or through direct contact with carrier wild birds.
As for viral transmission to humans, this can occur through interactions with live poultry and handling raw poultry meat, but also through frequenting potentially contaminated environments, such as production facilities or poultry markets.
As mentioned, human-to-human transmission has occurred, albeit rarely, showing a limited capacity for spread. We reiterate, however, that these viruses can mutate frequently and acquire pandemic potential.
Among other things, there is evidence of airborne transmission of these pathogens, both within livestock and from animals to humans.
Hygiene, cooking, and storage of meat and eggs: best practices
The possibility of contracting the virus through handling infected animals raises some food hygiene questions. The Istituto Superiore di Sanità (ISS) provides some guidance, based on a joint statement by the FAO (Food and Agriculture Organization) and the WHO (World Health Organization).
Regarding poultry meat, even if it comes from “non-risk” areas (i.e., areas free of active avian influenza foci), it is good practice to cook thoroughly, subjecting the product to temperatures greater than or equal to 70°C. The optimal temperature must reach the core of the food, eliminating the pinkish coloration typical of raw meat. It should be specified, for greater understanding of the topic, that highly pathogenic viruses reach all body districts of the infected animal, and that such a temperature is capable of neutralizing them. As for eggs, the virus can be found on the shell, but also inside. It is therefore advisable to cook eggs until the yolk is completely solidified.
An important aspect concerns freezing and refrigerating raw meat: these are two necessary practices for optimal food preservation, but incapable of sanitizing infected meat. In other words, they do not kill viruses already present in the meat originally. The same principle, intuitively, extends to infected eggs stored in the refrigerator.
In addition to cooking, it is advisable to apply further hygiene procedures. First, it is necessary to prevent any contact between raw meat and ready-to-eat foods to avoid possible contamination of the latter. For the same reason, it is important not to use the same utensils and surfaces for raw meat and cooked foods, while washing and disinfecting everything involved in the processing environment. The use of disposable gloves, as well as frequent hand washing, are essential habits for those who handle food.
The above guidance is necessary for rural production settings, and especially so for at-risk geographic areas. Even in non-risk areas, however, it is advisable to achieve a reliable level of hygiene. Industrial production, on the other hand, prevents infected animals from entering the production chain, thanks to standardized safety measures.
Multi-level prevention in poultry farms
In the management of poultry farms, the prevention of infection risk related to avian influenza takes on significant importance. When well applied, it protects the sector from significant economic losses and limits, as much as possible, risky human–animal contacts. In this regard, it is important to prevent the entry of wild birds from outside, as well as to set up feeding and watering areas indoors. Periodically, it is also advisable to apply sampling procedures on animals, followed by targeted laboratory tests.
With regard to environmental sanitization, it is good practice to act on multiple levels, applying both classic protocols and new supporting technologies (to be detailed shortly).
Ventilation, air exchange, and sanitization protocols
Air exchange is the basic expedient to control the accumulation of viral particles in bioaerosols. To make it constant, it is possible to use mechanical ventilation systems (MV), which are absolutely essential for indoor areas. The most modern devices, moreover, are equipped with high-efficiency filters and air quality monitoring systems.
Equipped with washable surfaces, compliant farms are, desirably, subjected to systematic sanitization procedures. At the same time, surface washing precedes the application of disinfectants.
Environmental support technologies: what they are and when to use them
With its innovations, technology can support the sanitization of indoor environments, including farms. Air purifiers equipped with HEPA filters, for example, make it possible to remove very small particles from the air we breathe, such as viruses. Ionizing devices, secondly, damage microorganisms in bioaerosols by generating negative ions in the environment. UV-C lamps are also of interest, acting as a germicidal expedient by emitting ultraviolet radiation. Electromagnetic wave devices, on the other hand, impact suspended viruses using microwaves. In the following paragraphs, we will provide some basic information on this last technology.
Undoubtedly functional to indoor air quality, these tools require use compatible with the safety of people and animals. It is therefore advisable, for this purpose, to adhere to the specifications of each product by consulting the accompanying guidelines.
e4life electromagnetic wave devices
The electromagnetic wave technology developed by e4life has been recognized among the innovative techniques in the reference practice for indoor environment sanitization UNI/PdR 173-1 defined in collaboration with the Istituto Superiore di Sanità for the design of its devices. Adaptable to multiple protection needs, they meet the criteria of non-chemical sanitization while ensuring greater than 90% effectiveness. In the development of its products, the company aligns with the “One Health” concept, recognizing the interconnection between human, animal, and environmental health.
Operating principle for inactivating airborne viruses
The emission of microwaves at a specific frequency, inducing mechanical stress in the targeted viruses, is the mechanism by which the devices work. Specifically, they damage viral particles at the outer shell, rendering them inactive and no longer dangerous to human health.
Evidence, safety, and compliance of use
Like any tool of old or new generation, electromagnetic wave technology is adapted to safety and applicability needs. Let’s see which ones.
Safety, maintenance, and integration with other measures
As far as safety criteria are concerned, e4life devices comply with European directives on electromagnetic compatibility and on the exposure of biological tissues to microwaves. These are, ultimately, safe and efficient tools, while also boasting a certain versatility. For the healthiness of farms, in fact, the company offers e4farm, the device designed to counter avian influenza, among other things. For a winning synergy, moreover, the technology can be combined with other preventive tools, such as those mentioned earlier (e.g., mechanical ventilation). Lastly, and not least, e4life devices are easy to install and do not require periodic maintenance procedures.
FAQs
How dangerous is avian influenza in humans?
To date, avian influenza has rarely affected humans, sometimes causing severe respiratory symptoms. Among other concerns, there is fear that avian influenza viruses could cause a pandemic.
How to avoid avian influenza infection?
Preventive actions are essential in poultry farming. Specifically, it is important to prevent the entry of wild species, apply systematic sanitization measures, and conduct periodic analyses on livestock.
Do e4life devices prevent avian influenza on their own?
These devices provide an additional means of countering avian influenza, within the context of broader prevention.
Can they be used in the presence of people?
Yes, these devices are completely harmless to people and animals.
Do they replace ventilation and cleaning?
e4life devices are designed to integrate conventional preventive measures.
