[The effects of chlorine disinfection on the resistance of bacteriophage f2 in water].

Under defined conditions, E. coli bacteriophage f2 was subject to repeated disinfection by chlorine 10 times. The survival bacteriophage f2 was compared with its original strain in resistance to chlorine. Experimental results showed that bacteriophage f2 increased its resistance after chlorine disinfection. The increased resistance varied under different conditions. The higher the pH, the greater the increased resistance. The survival bacteriophage f2 maintained its increased resistance though it was passaged 10 times in nutrient broth. The reason for the increased resistance of bacteriophage f2 after chlorine disinfection was probably the chlorine-induced mutation or spontaneous chlorine-resistant mutation.