Viruses and viral illnesses have for thousands of years been at the forefront of research, agriculture and medicine, with virology as a major challenge. Smallpox is a prime example. Smallpox is also the only disease ever eradicated on the planet that has made history literally different during the European conquest of the New World. Unfortunately, there have been very little general knowledge scientific developments in virus understanding. It is difficult to understand relevant facts, and it can seem inconsistent as though one researcher's advice is rejected. Furthermore, confusion is rampant on viruses and vaccines. This false information is persistent, widely circulated and increasingly difficult to overcome as the Internet provides more people with health information. Growing percentages of the parents prefer to delay or reject their child's vaccinations to avoid several kinds of harmful Viral Infections. Typically, vaccines work by creating "herd immunity," where vaccination is sufficiently large to prevent the maintenance of viral transmission lines to reduce susceptible hosts. However when vaccine levels decline too low, person to person infections can spread easy, leading to widespread disease outbreaks. This paper highlights about vaccines in Virology field.