Rent Zaion (2001 - 2001)

Zaion is a Japanese Sci-Fi animation about a war between humans and monsters and a world being decimated by a virus that is claiming more and more humans every day, turning the victims into the very monsters mankind is fighting. The series is set after a meteorite carrying the virus crashes on the planet. To combat the spreading virus, mankind creates a special type of soldier to combat the infection but they are said to be fighting a losing battle against a foe that keeps growing.