The XT7 Anthro-Sanguini Infection
Infected humans develop into cannibalistic and aggressive personalities. They are weaker in the day and faster and stronger at night, people stricken with this are known as Roamers or The Infected.
XT7 is believed to be absorbing solar energy during the day and it is thought that Roamers generally slow down most body functions during this period while their body recharges. And when the sun is down they are recuperated, more aggressive and faster.
Scientists at the Willard Shephard Foundation researched into a possible antigen called XT9, which in some tests proved successful. CODENAME VASQUEZ was the name of this project and it was proving very successful. However before full human testing could take place, riots caused by the aggressive plague created unavoidable circumstances in Willard's Los Angeles labs. Dr Mason and his team are thought to have been killed by gangs of roamers attacking the labs in that area. Dr Vasquez's teams, who were in another lab further south were also thought to be either killed or missing. No one knows for sure.
Roamers generally have a weakness to garlic and avoid it, this is because of the highly antibiotic nature of garlic which destroys XT7 on impact. So it's a good idea to eat some garlic and keep some fresh cloves with you at all times. It is even thought that if you consume garlic immediately after being infected, it can destroy the infection - However this has to be done immediately as the effects of the Anthro-Sanguini virus are so fast that the human host changes behaviour rapidly.