The Spanish flu virus, responsible for the deaths of 50 million people from 1918 to 1919, is likely a strain of virus that originated from poultry and birds. This is the assertion made by American scientists after they found that the 1918 virus shares genetic mutations with the H5N1 avian influenza virus currently rampant in Asia.
In an article published in the journal Nature, the scientists stated that their research highlights the current threat posed by the H5N1 virus to humanity. A second study published in the journal Science revealed that another group of researchers in the United States successfully recreated the 1918 virus in mice. The virus is being stored at the Centers for Disease Control and Prevention (CDC) in the U.S. under strict safety conditions. They intend to conduct experiments to further understand the biological characteristics that made the 1918 virus so dangerous.
The 1918 virus was reconstructed from data collected by a research team from the Armed Forces Institute of Pathology (AFIP). By processing samples from the bodies of victims of the 1918 flu pandemic, the research team was able to assemble the complete genetic sequence of the virus. They discovered that the 1918 flu virus contained novel factors for humans at that time, making it extremely dangerous. The analysis of the last three segments of the virus’s genetic code showed mutations very similar to those found in avian influenza viruses, such as H5N1 currently present in Southeast Asia.
Many experts are concerned that H5N1 or a similar strain could cause significant fatalities in humans after combining with a human flu strain. It is only a matter of time. The danger lies in the mutations that American scientists discovered, which are located in the genes controlling the replication of the 1918 virus in host cells. These mutations may have enabled the 1918 virus to spread more effectively. They also noted that currently, H5N1 shares only some, not all, of the mutations found in the 1918 virus.
Nevertheless, these mutations might be sufficient to increase the danger posed by the H5N1 virus, giving it the potential for serious human-to-human transmission without needing to combine with a common human flu strain. Researchers believe that two other major flu pandemics of the 20th century (1957 and 1968) were caused by human flu viruses. These human flu viruses acquired two or three crucial genes from avian influenza strains. However, they believe that the 1918 flu virus was likely entirely an avian influenza virus that adapted to function in the human body.
Julie Gerberding, Director of the Centers for Disease Control and Prevention in the U.S., stated: “The discovery of the 1918 virus helps us uncover some secrets for predicting and preparing for the next flu pandemic.” According to Professor John Oxford from Queen Mary University, the research indicates that we need to take H5N1 more seriously than we currently do.
Minh Sơn (According to BBC, CNN)