The use of cephalothin and triphenyltetrazolium chloride impregnated filter paper strips in the identification of Campylobacter species.

Filter paper impregnated strips using cephalothin at 30 and 60 micrograms/ml and triphenyltetrazolium chloride at 20 mg/ml were prepared and used in the typing of catalase-positive Campylobacter species. There was no difference in the sensitivity of campylobacters to cephalothin at 30 micrograms/ml and 60 micrograms/ml. Results were as reported by other workers except for a C. jejuni strain which was resistant to the triphenyltetrazolium. The technique is nevertheless inexpensive and the results are consistent and easy to interpret.