3 Apr 2018 //

Outbreak of Influenza in the United States (2017-2018)

A Hundred Years after the 1918 Spanish Flu and We Are Now Experiencing a Similar Thing? Outbreak of Influenza in the United States (2017-2018)

“The 1918 has gone: a year momentous as the termination of the most cruel war in the annals of the human race; a year which marked, the end at least for a time, of man’s destruction of man; unfortunately a year in which developed a most fatal infectious disease causing the death of hundreds of thousands of human beings. Medical science for four and one-half years devoted itself to putting men on the firing line and keeping them there. Now it must turn with its whole might to combating the greatest enemy of all—infectious disease,”

– Journal of the American Medical Association final edition of 1918

 

The Spanish Flu Pandemic of 1918: The Deadliest in History

The World War I, one of the deadliest conflict in the history of human race, had killed 16 million people. The Influenza Pandemic of 1918 or known as the 1918 Spanish Flu—killed more than that. Cited as the most devastating pandemic in the history, this illness had taken away between 20 until 40 million lives. It was beyond disaster.

In the fall of 1918’s Great War in Europe, American allies had joined the fight. Between the midst of the trenches, the men had lived through some very brutal condition of living. Then, something erupted—what was then thought to be cases of benign common cold was not the case at all. Two years after, a fifth of the world was infected by the disease. The pattern of the morbidity of the disease was rather odd—the disease was deadly in the age of group between 20 and 40, where it was previously known to be the killer of the children and elderly. Of the U.S. soldiers who died in Europe, half of them fell due to this catastrophic disease.

A physician wrote that patients who ought to have common influenza by that time would “develop the most viscous type of pneumonia that has ever been seen” and cyanosis (a condition which is marked with bluish discoloration of the skin due to poor circulation or insufficient oxygenation of the blood), “it is simply a struggle for air until they suffocate,” (Grist, 1979). Another physician said that patients with the influenza would have “died struggling to clear their airways of a blood-tinged froth that sometimes gushed from their nose and mouth,” (Starr, 1976).

This pandemic affected everyone—with one-quarter of the US and one-fifth of the world. Escaping from this disease was impossible. That time, the war gave science greater importance as governments relied on scientists, as their new technologies could preserve the men on the front and ultimately save them. These conditions created by World War I led to the relatively calm response of the public and application of scientific ideas. The medical and scientific communities had applied their theories to prevention, diagnostics and treatment of the influenza patients, at that time.

 

A Shapeshifting Foe: The Influenza Virus and the Epidemic of Flu 2017-2018

This year, CDC has called the 2017-2018 flu as an epidemic. While there are many types of virus that can elicit flu-like syndrome (such as Rhinovirus which is a type of virus that is responsible of causing common cold), this serious epidemic is mainly caused by the influenza virus. One thing about influenza virus is that its behavior is unpredictable, as it may experience ‘shapeshifts’ from time to time. Thus, flu is able to kill thousands of people each year in the United States alone, and without a doubt many more globally. Forecasting which strains that will predominate the next season of flu is important in designing a well-matched vaccine—but it has its own challenges.

This year’s flu season started with a dominant strain of H3N2 and a poor-matched vaccine. Data from CDC shows that as of 3 February 2018, 7.7 percent of all visits to the doctor in the United States are due to flu-like syndrome, a number which jumped three times from the national average.

The question lies on what makes this years’ influenza virus to be highly elusive?

Professor of Medicine at the Harvard Medical School, Daniel Kuritzkes, explained that the ‘shapeshifting’ manor of the virus comes from its genetic make-up. Influenza is an RNA virus, which means that it needs RNA enzyme to replicate and duplicate-self—and apparently, RNA enzyme is very sloppy and does not have any proofreading system to correct any mutations that comes after the replication process.

These mutations, if too much, may cause the virus to die—which is good. But if just enough, it may create variations of the surface antigens—the antigens that our immune system must recognize. Thus, when these surface proteins change, our immune system may not be able to recognize the viruses anymore. This is the reason why our last year’s made-up antibody may not work against this year’s invading influenza virus.

But, there is another reason why influenza virus is so elusive. Influenza virus is made up of 8 different RNA segments. When we got infected by more than one flu strain, the strain may swap segments—creating a new re-sorted type of virus. Figuring out how to tackle these problems provides challenges for scientist.

A big change-maker would be a universal influenza vaccine. The current available vaccine is the seasonal vaccine, which are premade each year based on experts’ prediction towards which strains that may predominate that year. These seasonal vaccine targets the surface proteins—which is mentioned earlier, while the universal influenza vaccine would target the core proteins of the virus. Hopefully, these vaccines would be able to be injected only a couple times during lifetime and provide long-lasting immunity. Clinical trial in humans is now currently underway in United Kingdom, based on the research of the Oxford University.

A total of 128 influenza-associated pediatric deaths have been reported for the 2017-2018 flu season. A flu-weakened immune system makes a person to be more susceptible in having serious bacterial infection, such as those of pneumonia that may lead to complications and turn to be fatal. It seems that this secondary bacterial infection is the leading cause of death in this years’ epidemic as well as the 1918 pandemic 100 years ago.

Full manuscript of the final manuscript of the JAMA journal final edition of 1918 can be accessed from this link.

 

References

  1. Billings M. The 1918 Influenza Pandemic [Internet]. Virus.stanford.edu. 2005 [cited 3 February 2018]. Available from: https://virus.stanford.edu/uda/
  2. Pesheva E. A Fickle Foe | HMS [Internet]. Hms.harvard.edu. 2018 [cited 26 February 2018]. Available from: https://hms.harvard.edu/news/fickle-foe
  3. Paules C, Sullivan S, Subbarao K, Fauci A. Chasing Seasonal Influenza — The Need for a Universal Influenza Vaccine. New England Journal of Medicine. 2018;378(1):7-9.