Anthrax sepsis, or primary anthrax sepsis (lat. sepsis anthracica prima), is an acute form of anthrax, characterized by the development of severe sepsis, mainly in people who have not had contact with animals, and manifested by fever, chills, headache, insomnia, pain in muscles and joints, skin rash, enlarged liver and spleen, symptoms of peritoneal irritation, sometimes signs of meningoencephalitis and polyarthritis.