Hydrogen sulfide produced in a cystine medium. Slight acid without gas may be produced from glucose, glycerol, maltose, mannose, fructose and dextrin. Growth soluble in sodium ricinoleate. Aerobic. No growth anaerobically. Temperature relations: Optimum, 37° C. Thermal death point, 56° C. for 10 minutes. Survives best at low temperatures, even -70° C. Pathogenicity: Penetrates unbroken skin to cause infection. Buboes and areas of necrosis produced in human and animal tissue. Infectious for man and most rodents, including rabbits, guinea pigs, rats, mice, squirrels, ground hogs, muskrats, beavers, water rats and lemmings. Source: Originally isolated from Cali- fornia ground squirrels and later from more than 30 other forms of wild life in the United States and elsewhere. Found in lesions in man and animals with natural or experimental infections. Found especially in the livers, blood, lymph nodes and spleens of animals. Habitat: The cause of tularemia in man; transmitted from wild animals to man by blood-sucking insects, by contact with infected animals or by drinking water. Disease known in North America, Japan, Russia, Norway, Sweden, Austria, Turkey, Czechoslovakia and Central Germany. See Burroughs, Holdenreid, Longanecker and Meyer (Jour. Inf. Dis., 76, 1945, 115) for a complete list of known vertebrate hosts.
9. Pasteurella novicida Larson et al., 1955. (Larson, Wicht and Jellison, Public Health Reports, 70, 1955, 253.) no.vi'ci.da. L. adj. novus new; L. v. n. suffix -cida from L. v. caedo to cut, kill; M.L. noun novicida new-killer. Description prepared by Jellison, April, 1955. Coccoid to ovoid or short, rod-shaped cells, 0.20 to 0.28 by 0.28 micron in tissues, 0.7 by 1.7 microns in liquid media and 0.47 by 0.47 to 0.94 micron on solid media. Capsules not observed. Non -motile. Gram- negative. No growth on plain agar without special enrichment. Gelatin (without added cystine) : Growth. No liquefaction. Glucose cj'stine agar colonies: 6 to 7 mm in diameter, translucent. Glucose cystine blood agar colonies: 8 mm in diameter, gray with a definite blue cast, smooth, slightly elevated, glistening, amorphous, entire. Good growth on pri- mary isolation. Yeast extract agar colonies: 3 mm in diameter, clear, convex, glistening; edges are smooth. Yeast extract- or cystine-containing agar shakes: After 8 days at room temperature, at 30° or at 37° C, growth occurs on the surface and at a depth not exceeding 0.7 cm. Surface colonies are 5 mm in diameter, and those within the agar are 1 mm or less. Horsemeat infusion agar: When infected liver or spleen is smeared over the surface, growth occurs only in the immediate vi- cinity of small pieces of tissue which adhere to the medium. Blood agar colonies: 4 mm in diameter; resemble those on glucose cystine blood agar. No hemolysis. Peptone broth: Abundant growth; mod- erately uniform turbidity; no pellicle; no surface growth; slight sediment which disintegrates on shaking. Litmus milk: Unchanged. Potato: No growth. Indole not produced. Hydrogen sulfide is produced. Acid but no gas from glucose, fructose, sucrose and mannose. Methyl red test is negative. Acetylmethylcarbinol not produced. Nitrites not produced from nitrates. Ammonia is not produced. Methylene blue is reduced. Catalase-positive. Aerobic, facultatively anaerobic. Temperature relations: Optimum, 37° C. Thermal death point, 60° C. for 10 minutes. Pathogenicity: Pathogenic for white mice, guinea pigs and hamsters. Produces lesions in experimental animals similar to those found in tularemia. Rabbits, white rats and pigeons are somewhat resistant; not known to infect man.
