Scientists Find New Discoverys Related To Mass Deaths Due To Spanish Flu

Virus illustration (Photo: Freepic/urzine)

JAKARTA - Recently, scientists succeeded in uncovering the genetic secret of one of the deadliest viruses in world history, namely the Spanish flu. This virus has killed up to 100,000 people worldwide between 1918 and 1920.

This discovery comes from the analysis of the lungs of an 18-year-old youth who died from the flu in Zurich, Switzerland, on July 15, 1918. In the study, researchers found this virus already had a number of mutations that increased its ability to infect human cells and made it much more deadly, even since the start of the pandemic.

Spanish flu is the deadliest global outbreak in history caused by influenza A (IAV) virus. However, more than a century later, scientists still face many obstacles in studying this virus. One of the challenges is that the genetic material of the influenza A virus is in the form of RNA, a molecule that is much faster damaged than DNA.

In addition, the victim's body tissue, which can still be accessed, has been preserved in chemicals such as formaldehyde, making it difficult to use for RNA analysis.

However, thanks to the latest RNA protocol, the research team managed to extract and analyze the genetic material of the virus from the victim's lungs.

This finding is important because the death toll in the first wave of the pandemic, namely in the spring of 1918, before the virus became much more deadly in the second wave that hit the world in the fall that year.

Surprisingly, the researchers discovered three important mutations that were previously believed to appear only during the second wave, apparently already present in the virus circulating in Switzerland in the first wave.

"In July 1918, the first wave of the virus had experienced several important adaptations to adapt to the human body," the researchers wrote in the journal BMC Biology, quoted from the IFL Science page.

It is known that two of these mutations help the virus avoid attacks from important antiviral proteins in the human immune system, namely the first human myxovirus resistance protein (MxA).

This protein serves as the body's natural defense of the flu virus from animals. However, the mutations found allow the Spanish flu virus to fight this defense system and still infect the human body.

Other adaptations lead to changes in the shape of a virus surface protein called hemagglutinin, which plays an important role in the process of the virus attached and entering human cells, similar to how the SARS-CoV-2 virus targets ACE2 receptors in the COVID-19 pandemic.

According to the researchers, this sample from the lungs of the victims in Zurich is the only genome from the first wave that has the three mutations.

"These mutations may provide benefits to the virus during the pandemic, considering that all genomes from the second wave analyzed also show similar mutations," explained the research team.

"This is the first time we have access to influenza genomes from the 1918-1920 pandemic in Switzerland," said Verena Sch\"unemann, co-author of the study.

"This discovery opens new insights into how this virus adapted to Europe at the start of the pandemic," he continued.

Sch\"unemann and his team hope a better understanding of the evolution process of this virus can help the world in predicting and responding to the pandemic that may occur in the future.