The deadliest virus on the planet is the rabies virus.
The rabies virus has a characteristic bullet shaped virion structure and if someone is infected with rabies virus and it's left untreated it can become quickly fatal.
The Zaire Ebola virus is also another deadliest virus on the plant which a mortality rate of 90 percent and it's a strain that is currently spreading through Liberia, Sierra Leone and Guinea.
Zaire ebolavirus (ZEBOV) is a filovirus that causes a severe and often lethal viral haemorrhagic fever in primates and humans. Since the first documented outbreak in Yambuku [128], there have been at least eight major outbreaks across Western Africa.
The Spanish Flu is also another deadliest virus that killed around 25 million to 50 million people.
The 1918–1920 flu pandemic, which is also known as the Great Influenza epidemic or by the common misnomer Spanish flu, was an exceptionally deadly global influenza pandemic caused by the H1N1 subtype of the influenza A virus.
The Spanish flu started in 1918 and ended in 1920.
The Spanish Flu was caused by a highly virulent H1N1 influenza A virus, and is believed to have originated from an avian (bird) source, which mutated to infect humans and spread globally due to troop movements during World War I.
The Spanish Flu's devastating impact came from its unique genetic combination, causing severe lung inflammation (pneumonia) and overwhelming healthy young adults, often leading to secondary bacterial infections.