Reacción a "Reactions: Confirmed case of swine flu in a worker on a farm in Catalonia"

The natural reservoirs of the influenza virus are aquatic birds. Different influenza viruses are capable of infecting birds and mammals, including humans and pigs, but they also infect sea lions, seals, horses, dogs... Influenza viruses that infect humans and pigs often have many similarities and can easily jump from humans to pigs. In fact, when analyzing the influenza viruses found on a pig farm, human influenza viruses are often detected. People who have more contact with these animals, such as farm workers, can transmit the viruses to the animals and become infected with the influenza viruses carried by the pigs. In fact, the virus of the first pandemic of the 21st century was a swine-origin influenza virus, an H1N1.

The risks to the community are the same as those posed by circulating influenza viruses. The problem arises when a swine or human virus 'recombine' with another influenza virus. This gives rise to new viruses, such as the pandemic H1N1 virus of 2009. To prevent community risks, the most important thing is to conduct epidemiological surveillance of circulating viruses on farms and of people who are in contact with sick animals. This way, necessary measures can be implemented to protect both animals and people.

Cases of swine influenza viruses infecting humans and vice versa are relatively common in people who have contact with infected animals. It should not be a cause for social alarm as long as we remain vigilant for possible new 'recombinant' viruses or new viruses with mutations. That's why it's so important to stay vigilant.