[1] Mil Med Acad, Dept Infect Dis, Sofia, Bulgaria
[2] Univ El Oued, Fac Nat & Life Sci, Dept Biol, POB 789, El Oued 39000, Algeria
[3] Univ El Oued, Fac Nat & Life Sci, Lab Biol Environm & Hlth LBEH, POB 789, El Oued 39000, Algeria
[4] Trakia Univ, Fac Vet Med, Dept Microbiol Infect & Parasit Dis, Stara Zagora, Bulgaria