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From Our Mailbag: Did the Influenza Virus Cause the 1918-1919 Influenza Pandemic?


René F. Najera, DrPH

December 7, 2021

We get . The overwhelming majority of them are from people thanking us for our work on the project, or with constructive criticism on how to make the project better. Once in a while, we get an email from a person questioning the historicity of events we cover, or they question the science and evidence of vaccination. Some of the email senders are somewhat justified in their skepticism of vaccine science. After all, many of the concepts that go into the science and history of vaccines can be very complicated.

For example, a recent email questioned the cause of the 1918-1919 influenza pandemic, stating that it was not the influenza virus that caused it, that it was caused by a bacterium, and that the bacterial infections appeared from a vaccine against meningitis given to American troops. They further stated that viruses were not discovered at the time of the pandemic. First, the facts:

  • The 1918-1919 influenza pandemic was caused by an H1N1 strain of influenza of avian (bird) origin. (Source: )
  • Viruses were discovered in the late 1800s, and the techniques for isolating them only accelerated from there. (Source: )
  • While a meningitis vaccine was trialed in US troops stationed at Fr. Riley in 1918, there is no evidence of any widespread disease similar to influenza among those who took the vaccine. (Source: )
  • Furthermore, by 1918, there were plenty of techniques for finding and isolating bacteria -- like those that caused meningitis, hence the vaccine -- yet neither meningitis or the bacteria that cause meningitis were found in the cases of influenza worldwide.
  • Finally, while it is true that many deaths occurred in otherwise young, healthy people during the pandemic, and that many of those deaths were from superinfections (secondary bacterial infections) from a weakened state due to the virus. This was the pre-antibiotic era, after all. (Source: )

In their email, the reader/skeptic states some truisms that seem to prove their case:

  • "The CDC has even posted an article that people died from bacterial flu and pneumonia in 1918 and not a virus as your site says after a large worldwide study was done in the 1980s proving it."
    FACT CHECK: Yes, as stated in the facts above, many people had a secondary bacterial infection that resulted from their weakened state from the influenza infection. However, for this to happen, the influenza virus was necessary. Absent the virus, those secondary infections likely do not happen. There is even some thought that a previous influenza (H3N8) infection led to a debilitated H1N1 response from the immune system. (Source: )
  • "The CDC tries to still blame it on a virus, but there was no methods back then for detecting any virus and the Study shows people only dying from bacterias (sic). Authors are just assuming a virus was involved and use phrases "most probably", etc."
    FACT CHECK: As stated in the facts above, viruses were discovered in the late 1800s. But, even if they had not by the end of the 1918-1919 pandemic, that doesn't mean that methods for detecting the virus didn't come along that allowed a retrospective analysis of what happened. For example, people who lived through that pandemic had higher antibody levels against H1N1 in the 2009 pandemic than others. (Source: ) Furthermore, the virus was recovered from bodies of victims of the 1918-1919 pandemic. (Source: )
  • "The U.S. Army even acknowledges the first person to get the so-called Spanish flu (in the world) was an army cook at Ft. Riley, KS. Coincidentally from the same pathogen (Meningitis) used in the inoculations given to all the military personnel in the U.S. and around the world."
    FACT CHECK: As stated in the facts above, the meningitis vaccine was only given to a few thousand troops at Ft. Riley, and not "to all the military personnel in the U.S. and around the world." (Source: ) Those vaccinations happened in October and November of 1917. The first cases of influenza at Ft. Riley did not appear until March. (Source: ) That is four months post vaccination before the first influenza cases. Finally, while the first cases in the United States were reported in Kansas, there is no evidence that supports the assertion that Ft. Riley was the site of the first cases worldwide. The world was still fighting World War I, and, for strategic purposes, no country would voluntarily report that their troops were unable to fight. The first cases could have been in the United States or even Europe (Source: ) As COVID-19 has shown us most recently with the Omicron variant, viruses are often well on their way to other parts of the world before they are first recognized somewhere. (Omicron was first detected in South Africa, but subsequent retrospective investigations have found .)

The rest of the message from this particular reader devolved into accusations of conspiracies between pharmaceutical companies and governments to hurt the human population, to control the human population, or to gain profits from the lives of the human population. Those accusations will not be addressed here.

Unfortunately, people like the reader who emailed us are out there, and some of them even hold positions of power that affect public health policy. Luckily, they are in the minority in their opinions. When President Biden mandated that the federal workforce receive the COVID-19 vaccine, . With regards to childhood vaccinations, even conservative states like Mississippi and West Virginia do not allow philosophical or religious exemptions for children who attend public schools, . Thus, the anti-vaccine thinking does not permeate all of society, or even all of one segment of society. The views on science and vaccination are as diverse as the people of the United States, and the world. However, those who deny science and fight () against it, are, simply put, small in number and relevance.


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