While the H5N1-VogelGrippevirus relentlessly spreads in animals Around the World , who want to understand how a H5N1-Pandemie could be used, a rich source of references: data on the immune response of the immune system to Influenza .

This information provides information on who could be the most at risk in an H5N1 pandemic. Earlier research also suggests that our immune system would not start at zero in the event of a virus-thanks to previous infections and Vaccinations against other forms of flu. However, this immunity would probably not prevent H5N1 causing serious damage to global health if a pandemic would break out.

from feathers to fur

The now rampant H5N1 strain started as a bird's pathogen and then spread to mammals. Due to its fatal effect in the event of birds, it has killed millions of user and wild birds worldwide due to its fatal effect. data-track category = "references"> 1 It has also spread to a growing list of mammal species, including seals and Foxes , and has asked for more than 460 lives since 2003.

So far, the virus has not yet gained the ability to effectively spread from person to person, which has so far kept the potential of pandemic. But his repeated exaggeration of birds to mammals and references to transmission under mammalies, such as elephant seals ( mirounga leonina ) 2 have alerted researchers who warn that the virus is increasingly getting opportunities to spread easily between people.

These worries have been reinforced, as H5N1 was first detected in US cattle in March animals that often interact with people. Until July 8th, US health officers have confirmed bird flu infections in almost 140 herds of dairy in 12 states and 4 dairy farmers.

All employees had slight symptoms, but scientists warn that the virus is still a threat. It is possible that the workers have escaped a serious illness because they may have captured the H5N1 by contacting milk from infected cows and not through the usual air -transmitted particles, says Seema Lakdawala, a flu virologist at Emory University School of Medicine in Atlanta, Georgia. Or maybe because the workers may have been infected over the eye and not about the typical path of the mouth or the nose.

Malik Peiris, a virologist at the University of Hong Kong, says that he was not surprised by these infections, "still calms that the mildness of these cases means that this virus is naturally mild".

immune preparation

The inherent virus of the virus is not the only factor that would form a pandemic, says Peiris. Another is the condition of the willingness of the immune system.

By combining earlier infection and immunization, people have had significant contact with the flu up to adulthood in general. Some estimates 3 indicate that up to half of the younger population annually with 'seasonal ’ Flu is infected, which causes regular infection waves.

Contact with seasonal flu, however, only offers limited protection against the new flu strains that could cause pandemics. These tribes differ genetically from the circulating seasonal tribes, which means that they have less constructed immunity in humans and can therefore be more dangerous.

At the present time, H5N1 does not spread easily from person to person. But scientists fear that if this ability has achieved this ability, it could trigger a pandemic, since it is genetically different from the seasonal flu viruses currently in circulation. Tests of people in the United States showed that only a few antibodies against today's H5N1-Stamm. This indicates that "the majority of the population would be susceptible to infection with this virus if it would easily infect people," said the US centers for illness control and prevention that carried out the tests.

good news, bad news

However, this does not mean that people are completely unprotected because contact with an older pandemic flu tamer can protect a new one, says Michael Worobey, an evolutionary biologist at the University of Arizona in Tucson. For example, the Pandemie from 2009 by the Schweingrippevirus H1N1 causes 80% of deaths in humans under the age of 65 4 . Older generations were spared Immunity that comes from contact with various H1N1 tribes when they were younger.

Contact with H1N1 during the 2009 pandemic and at other times could again offer certain protection against the H5N1 strain that arises today. Both the H5N1 and the H1N1 viruses have a surface protein called N1, and an immune system that reacts to H1N1 could also react to H5N1. Peiris and his colleagues found that the almost universal exposure to H1N1 in 2009 and the following years produces antibodies that react 5 . He now carries out animal experiments to determine whether this antibody reaction offers protection against infections and serious illnesses.

The all -important first flu case

There is another more difficult factor for the immune response to H5N1: The first flu case of one person could have an overlying influence on their future immunity . In a study published in 2016 6 analyzed WOROBEY for almost two decades Subtypes of the bird flu, H5N1 and H7N9. They found that people generally remain without prejudice from the flu tribe that matches the best that caused their first flu, while they are more vulnerable to uniform tribes.

so far, people who were born before 1968 have probably avoided the effects of H5N1 because they probably had their first flu at a time when the dominant flu virus in circulation corresponded to H5N1. However, those who were born after 1968 have so far escaped the worst effects of H7N9 because their first contact with the flu was probably with a virus that fits H7N9 and not H5N1. Through the first infection, 75% protection against serious illness and 80% protection against death with a matching bird flu virus, the authors found out.

If an outbreak of H5N1 occurred, this initial case predicts that older people could be spared again and that younger people would be more susceptible, according to which. "We should have it somewhere between the front and back of the head," he says.