Viruses are microscopic yet extremely dangerous organisms on this planet. Many viruses cause mild infections; however, several others are known as the deadliest ones. Viruses are obligate parasites, which means that they require a host body to replicate and reproduce as they are completely inactive outside the host cell. Once these viruses enter a host body, they target the vulnerable cells and causes diseases. Viruses have the ability to cause neural, respiratory, cardiovascular, gastroenteritis, pharyngitis, sexually transmitted diseases, eye infections, skin infections and much more.
Viruses come from different families, and there are more than hundreds of virus families that infect humans. With the discovery of every new virus, scientists from all around the world start their research to develop a cure for it. A number of viruses have vaccines against them; however, many are still incurable and cause fatalities.
