Spanish Flu: The Deadliest Pandemic in History

The Spanish flu pandemic of 1918-1919 was the deadliest in history. It is estimated that up to 100 million people died from the virus, which is more than three times the number who died in World War I. The pandemic began in Spain, but quickly spread around the world. Despite the fact that the 1918 flu was not concentrated to one location, it became known throughout the world as the Spanish flu because Spain was severely affected by it. In some areas, as many as one out of every four people contracted the virus and died. The cause of the Spanish flu remains a mystery to this day, but scientists believe it may have been a mutated form of H1N1 influenza. In 1918, a new influenza virus emerged. During this same time period World War I was taking place.The circumstances of World War I (overcrowding and worldwide troop movement) contributed the 1918 flu epidemic spread. Healthy young people's vulnerability and the scarcity of vaccines and therapies resulted in a massive public health emergency, resulting in over 50 million fatalities worldwide, including roughly 675,000 in the United States. The virus caused severe respiratory illness in its victims and was often fatal. Symptoms included fever, coughing, and difficulty breathing. There is no specific treatment for the Spanish flu, but patients can receive supportive care to help them recover. Prevention of the virus is through vaccination.

What is Spanish Flu?

The 1918 pandemic, also known as the "Spanish flu" or the "Great Influenza outbreak," was a deadly worldwide influenza pandemic that originated with the H1N1 influenza A virus. The 1918 Spanish flu was the first of three flu epidemics sparked by the H1N1 influenza A virus. The most recent one was the 2009 swine flu pandemic. Clinical symptoms of the 1918 pandemic were similar to those seen in the 1889 pandemic, including a "dull" heliotrope cyanosis of the face that progressed rapidly. Because of this bluish-violet cyanosis in dying individuals, it was given the name 'purple death.'

Pathways associated with Flu infection:

• NF-κB has been implicated in the immune response. It's also a known target of many viruses. The NF-κB signaling pathway is activated during viral infection, and the gene expression levels of IFN-β/TNFα/IL8 are increased, suggesting that IKK-mediated NF-κB signaling is required for the host innate immune response.
• It has been documented that the viral NS1 protein activates the PI3K/Akt signaling pathway in order to aid viral replication.
• Influenza virus infection also activates all four members of the MAPK family, which has been demonstrated to promote viral RNA (viral ribonucleoprotein capsids) movement and virus production.
• Influenza viral infection activates the host cell's antiviral defenses, which include an increase in interferon levels. IFN α, IFN β, and IFN γ are three types of interferons produced by the body during response to viral infections. NF-kB activates a range of cellular genes, one of which is PKR, encoding double-stranded RNA activated protein kinase. PKR is activated and undergoes autophosphorylation after contact with dsRNA. The phosphorylation of the alpha subunit of eukaryotic initiation factor 2 (eIF2α) by activated PKR causes translation arrest. Indeed, studies have suggested that PKR is involved in the mediation of ds-RNA-induced apoptosis in cells.

Influenza related related products

Timeline of Flu pandemic:

• The United States entered World War I on April 6, 1917, when the American Expeditionary Force (AEF) first entered the war. Following an epidemic of flu-like symptoms in the United States. The count of affected persons continued to climb for the next six months. In a weekly public health report published on April 5, 1917, the first mention of influenza was made.
• The second wave of pandemic strikes in September 1918, when the American flu epidemic emerges at Camp Devens, a United States Army training camp outside of Boston that is extremely deadly and accounts for the majority of mortality attributed to the pandemic.
• The 1918 flu pandemic virus kills an estimated 195,000 Americans.
• January 1919, a third wave of the epidemic strikes in the winter and spring of 1919, causing widespread devastation. In the first five days of January in San Francisco, 1,800 flu infections had diagnosed and 101 deaths have been reported.
• By the end of the decade, the virus that caused the pandemic had evolved into a less deadly variant and therefore only seasonal flu was observed. By 1921, deaths had returned to pre-pandemic levels.

Signs and Symptoms of Spanish Flu

• The symptoms of the 1918 epidemic were extremely severe, and caused by cytokine storms. At first, influenza was misdiagnosed as dengue, cholera, or typhoid because the symptoms were so unusual.
• The typical flu symptoms of a sore throat, headache, and fever were reported by the majority of infected individuals: mostly during the first wave. However, during the second stage, the illness was considerably more serious, frequently progressing to bacterial pneumonia and being a cause of mortality. The second, more serious type would cause heliotrope cyanosis, in which the skin first forms two mahogany spots over the cheekbones before spreading to color the entire face blue, then black throughout the extremities and limbs, and finally extending to the torso.
• Bacterial pneumonia was the most common cause of death, followed by a secondary infection linked with the flu. Because of the damaged bronchial tubes of the victims, these pneumonia was caused by typical upper respiratory tract germs that had been able to enter the lungs via ruptured bronchial tubes. People died as a result of direct viral effects, including massive hemorrhages and edema in the lungs.

Transmission of Spanish Flu

The increased close quarters and large troop movements of World War I accelerated the epidemic, probably increasing infection rates as well as accelerating evolution. People's resistance to the virus may have dropped as a result of the war. Infection transmission was easier for soldiers, sailors, and other travellers thanks to modern transportation systems. The fact that the majority of people who recovered from first-wave infections had developed immunity suggested that it was the same strain of flu.

Treatment of Spanish Flu

Because there were no antiviral medicines available and no antibiotics to treat secondary bacterial infections, doctors would have to rely on a random assortment of medications with varying degrees of effectiveness, including aspirin, quinine, arsine, digitoxin, strychnine, epsom salts, castor oil, and iodine.

Preventive measures

Early diagnosis and treatment can improve your chances of recovery. If you are diagnosed with the flu, there are a few things you can do at home to ease your symptoms and prevent the virus from spreading to others. First, get plenty of rest and drink plenty of fluids. You should also avoid contact with other people as much as possible and practice good hygiene by washing your hands often and covering your mouth when you sneeze or cough. If you have a fever, take over-the-counter medication like ibuprofen to help reduce it. Spanish flu is a serious virus, but if caught early, most people will recover from it.

More information on Influenza virus

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