7 viral diseases that are the biggest killers

Viral diseases have existed from time immemorial and we humans have been fighting it for eons. With technological and medicinal advancements, we surely have found a way to prevent, battle some of the most fierce viruses in history. However, there seems to be no end to it and different, new viruses continue to emerge, wreaking more havoc than ever.

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There are many types of viral diseases that may affect different individuals in a different way. The most prevalent but curable viral disease is the common cold, whereas coronavirus or the SARs-COV-2 virus is currently the most deadly viral disease of all. That said, we list down some of the most deadly, fatal viral diseases that have and continue to cause a lot of harm in and around the world.

COVID-19 is an infectious respiratory illness that has existed among us for over a year and a half. It can range from mild, moderate to severe infections and if not acted upon quickly can lead to hospitalization and deaths. One of the most dangerous aspects of the virus is its unpredictability and its ability to mutate at a significant rate. As of now, according to the World Health Organization (WHO), there have been 236,599,025 confirmed cases of COVID-19, including 4,831,486 deaths, reported to WHO, globally.

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Coronaviruses are a large family of viruses found in both animals and humans, which are just not limited to COVID-19 or the SARs-COV-2 virus. It can also cause severe diseases such as Middle East Respiratory Syndrome (MERS). It was first identified in 2012 and according to the WHO had infected 2,499 people and caused 861 deaths globally. It is said that MERS has a mortality rate as high as 37.2% as opposed to the current estimated mortality rate of 2% to 3% for COVID-19.

Caused by a SARS-associated coronavirus, severe acute respiratory syndrome (SARS) can also lead to fatalities. It was first detected in February 2003, when a deadly outbreak took place in China and went on to affect four other countries. Given that it is an airborne virus, it can spread through tiny aerosol droplets. Besides, contaminated surfaces can also help it spread. Symptoms can go from mild fever, chills to headache, malaise, and muscle pain. Severe cases may lead to the need for ventilation and can cause deaths.

When the first ever Ebola outbreaks took place in the Republic of the Sudan and the Democratic Republic of Congo simultaneously, it alarmed doctors and scientists from around the world. The disease is said to spread through contact with blood or other body fluids, or tissue from infected people or animals. As per WHO data, "The average Ebola virus diseases (EVD) case fatality rate is around 50%. Case fatality rates have varied from 25% to 90% in past outbreaks." As of now, vaccines have been developed to prevent the spread of this deadly virus.

Acquired immunodeficiency syndrome (AIDS) is a chronic condition caused by the human immunodeficiency virus (HIV). It is a potentially life-threatening disease, for which there is no cure. However, due to the advancements in prevention, diagnosis, treatment and care, HIV infection has become a manageable medical condition. According to the WHO reports, "HIV continues to be a major global public health issue, having claimed 36.3 million (27.2–47.8 million) lives so far."

Influenza infection can cause acute respiratory illness and lead to a sudden onset of fever, cough, headache, muscle and joint pain, severe malaise, sore throat and a runny nose. The World Health Organization says that annual influenza epidemics result in about 3-5 million cases of severe illness and about 250,000 to 500,000 deaths. Currently, the alarming rise in the number of flu and COVID-19 cases have raised concerns all over the world. Doctors and medical professionals continue to urge people to take their flu and COVID vaccine shot immediately.

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There are four types of seasonal influenza virus namely type A, B,C and D. Both type A and B cause "seasonal epidemics" as per the WHO.

Type A influenza virus, the H1N1 flu, also known as the swine flu, is one of several flu virus strains that emerged in the spring of 2009. According to the Centre for Disease Control and Prevention (CDC), "It was detected first in the United States and spread quickly across the United States and the world. This new H1N1 virus contained a unique combination of influenza genes not previously identified in animals or people." The health body suggests that about 151,700-575,400 people worldwide died from (H1N1)pdm09 virus infection during the first year the virus circulated.