The Spanish Society of Epidemiology (SEE) has issued a call to “be prepared” in light of the possibility that avian flu could spread to humans. While the virus is currently “little adapted” to the human species and “the transmission is not frequent,” the SEE’s vaccination work group has developed a comprehensive guide to address doubts about the disease and its prevention. This guide aims to educate the public and healthcare professionals about the potential risks and preventive measures.

Epidemiologists have detailed that avian flu can be transmitted from wild birds to domestic poultry through air or contact with contaminated feathers, secretions, and excreta of infected animals. This transmission can occur in both wild and domestic settings, posing a significant threat to poultry farms and backyard flocks.

For the virus to transmit from birds to humans, close contact with infected birds or animals, whether alive or dead, or with environments contaminated by their secretions and excreta is necessary. Among people, the transmission would occur similarly to the seasonal flu, by air or by contact with surfaces contaminated by the virus. However, sustained transmission between humans has not been identified, although limited transmission cases have been described among workers on animal farms and their relatives.

In the United States, the Centers for Disease Control and Prevention (CDC) has been closely monitoring the situation. The CDC has reported that while cases in humans have been notified in the USA, in Spain and the European Union, infections have not been confirmed since 2020. Historically, the number of avian flu outbreaks in Spain has been very low compared to northern and central Europe, although it has been increasing in the last few seasons.

Due to the notification of avian flu cases in wild birds and domestic poultry, especially in neighboring countries such as France and Portugal, Spain has increased its alert level and implemented risk mitigation measures. One of these measures is the temporary prohibition of outdoor farming of poultry to prevent the potential spread of the virus.

To control and prevent avian flu, epidemiologists have emphasized non-pharmacological measures such as hand hygiene and avoiding contact with sick or dead birds, as well as pharmacological measures such as taking antiviral medications. The SEE has asserted that the development of a specific vaccine to reduce the risk of disease in humans is “a priority.” The European Medicines Agency (EMA) has issued favorable reports for the authorization of two new vaccines aimed at preventing human infection by this disease. These vaccines, ‘Celldemic’ and ‘inllipan,’ can only be used with the authorization of the responsible health institutions within the framework of an outbreak or a pandemic. The United Kingdom was the first country in Europe to acquire five million vaccines in December 2024.

For the moment, a sustained transmission has not been identified between people, although limited transmission cases have been described among workers of animal farms and his relatives.

Spanish Society of Epidemiology (SEE)

In Spain, the Ministry of Health has announced that it will purchase avian flu vaccines in the next joint purchase process of the European Union to distribute them among the population most exposed to possible infections, such as workers in poultry farms and veterinarians. Meanwhile, workers in contact with birds and certain mammals are vaccinated against the seasonal flu to avoid coinfection of the two types of flu viruses, as it could favor the appearance of a new subtype with transmission capacity among humans and cause a pandemic.

Epidemiological surveillance in farms and the use of adequate personal protective equipment are essential to mitigate the risk that would entail a greater adaptation of the virus to mammals. To address this health problem, experts have insisted that it must be focused from the ‘One Health’ perspective, since it has implications for human health, as well as for animals and the environment.

The World Health Organization (WHO) has also been studying the risk of avian flu transmission to humans, particularly in light of recent cases involving cats and other mammals. The WHO’s findings underscore the need for vigilance and preparedness in the face of potential zoonotic diseases.

In the United States, the Department of Agriculture (USDA) and the CDC have been working closely to monitor and mitigate the risk of avian flu. The USDA has implemented strict biosecurity measures in poultry farms and has been conducting regular surveillance to detect any potential outbreaks. The CDC, on the other hand, has been focusing on public health measures to prevent the spread of the virus to humans.

Recent developments in avian flu research have shown that the virus has the potential to mutate and adapt to new hosts. This adaptability raises concerns about the possibility of a future pandemic. However, experts emphasize that with proper surveillance, vaccination, and public health measures, the risk can be significantly mitigated.

In conclusion, while the risk of avian flu spreading to humans is low, it is crucial to remain vigilant and prepared. The SEE’s guide and the efforts of health organizations worldwide provide valuable resources and measures to prevent and control the spread of the virus. By taking proactive steps, we can protect both human and animal health and ensure the safety of our communities.

For more information on avian flu and its prevention, consult the CDC’s guidelines and stay updated with the latest developments from health authorities.