They say these guys have existed since the beginning of life on Earth. As far back as there's a plant or animal record, there are viruses. Life has adapted, changed, grown - and still the virus plagues it. It has been re-inventing itself over and over again in order to outwit, outlast and outplay its targets.
The virus of today is highly complex and nearly impossible to control or contain. Over the past million+ years, they've developed a level of survivalism and efficiency that is astounding to behold. We keep studying, keep trying to find new ways to defeat them, and they continue to calmly mutate around every new thing we throw at them.
We have been struggling with the deadliest, worst viruses since the beginning of humanity itself. Whether you've suffered from the common cold or something more rare and gut wrenching, you've definitely come into contact with a human virus.
521,000 Deaths a YearA third of the World’s population (over 2 billion people) has come in contact with this virus, including 350 million chronic carriers. In China and other parts of Asia, up to 10% of the adult population is chronically infected. The symptoms of acute hepatitis B include yellowing of the skin of eyes, dark urine, vomiting, nausea, extreme fatigue, and abdominal pain. Luckily, more than 95% of people who contract the virus as adults or older children will make a full recovery and develop immunity to the disease. In other people, however, hepatitis B can bring on chronic liver failure due to cirrhosis or cancer.
500,000 Deaths a Year
Influenza has been a prolific killer for centuries. The symptoms of influenza were first described more than 2,400 years ago by Hippocrates. Pandemics generally occur three times a century, and can cause millions of deaths. The most fatal pandemic on record was the Spanish flu outbreak in 1918, which caused between 20 million and 100 million deaths. In order to invade a host, the virus shell includes proteins that bind themselves to receptors on the outside of cells in the lungs and air passages of the victim. Once the virus has latched itself onto the cell it takes over so much of its machinery that the cell dies. Dead cells in the airways cause a runny nose and sore throat. Too many dead cells in the lungs causes death.Vaccinations against the flu are common in developed countries. However, a vaccination that is effective one year may not necessarily work the next year, due to the way the rate at which a flu virus evolves and the fact that new strains will soon replace older ones.
56,000 Deaths a Year
An estimated 200-300 million people worldwide are infected with hepatitis C. Most people infected with hepatitis C don’t have any symptoms and feel fine for years. However, liver damage invariably rears its ugly head over time, often decades after first infection. In fact, 70% of those infected develop chronic liver disease, 15% are struck with cirrhosis and 5% can die from liver cancer or cirrhosis. In the USA, hepatitis C is the primary reason for liver transplants.There is no cure, no vaccine.
197,000 Deaths a Year
Measles, also known as Rubeola, has done a pretty good job of killing people throughout the ages. Over the last 150 years, the virus has been responsible for the deaths of around 200 million people. The fatality rate from measles for otherwise healthy people in developed countries is 3 deaths per thousand cases, or 0.3%. In underdeveloped nations with high rates of malnutrition and poor healthcare, fatality rates have been as high as 28%. In immunocompromised patients (e.g. people with AIDS) the fatality rate is approximately 30%.
During the 1850s, measles killed a fifth of Hawaii's people. In 1875, measles killed over 40,000 Fijians, approximately one-third of the population. In the 19th century, the disease decimated the Andamanese population. In 1954, the virus causing the disease was isolated from an 11-year old boy from the United States, David Edmonston, and adapted and propagated on chick embryo tissue culture.To date, 21 strains of the measles virus have been identified.