Translated material
The secret of the Spanish flu has been revealed
The peculiarity of the Spanish flu pandemic is that it was perhaps the only case in recent history when the flu killed tens of millions of people. The usual annual epidemic is still more unpleasant than tragic: the next strain can put millions of people to bed with high fever and chills, but almost everyone recovers. The “Spanish flu” really killed: according to the most conservative estimates, at least 50 million people died from the virus in the world during that pandemic.
The mystery of the unusual properties of the “Spanish” virus has been worrying scientists for a long time, and we can say that the main causes of that pandemic are known. In particular, many mechanisms of the effect of the 1918 strain on the human body have been revealed, but virologists regularly find more and more new features of this pathogen. This time, American researchers paid attention to a protein called PB1-F2.
In fact, this protein is not exclusive to the Spanish flu. It is also present in other dangerous strains belonging to group A (including bird flu, which can be transmitted to humans). Virologists isolated this protein and began experimenting on laboratory mice. It turned out that PB1-F2 sharply increases the mortality of animals. Mice died in large numbers from so-called secondary pneumonia, and this is one of the main dangerous complications after the flu.
The fact is that death from the flu itself is quite rare. As a rule, the virus itself is capable of killing a person only if his body is very weakened. But fighting the flu “exhausts” the sick person, and then other pathogens come to the aid of the virus, for example bacteria that cause pneumonia. This was one of the main reasons for the high mortality rate in 1918-1919.
The Americans experimented not only with the suspicious protein itself, but also with an artificially synthesized strain of the virus that encoded PB1-F2, identical to that present in the “Spanish” variant of the pathogen. In all cases, the severity of the disease increased; the mice contracted viral or bacterial pneumonia and often died.
This study is not only of historical significance: since this protein is also encoded by many modern strains of group A, the results of the experiments can also be used in practice - during the next epidemic.