TY - JOUR
T1 - Rapid, sensitive recovery of recombinant attenuated Salmonella enterica serovar typhi vaccine strains from human blood
AU - Lottenbach, Kathleen R.
AU - Kelly-Aehle, Sandra M.
AU - Brenneman, Karen E.
AU - Curtiss, Roy
AU - Frey, Sharon E.
PY - 2013/9
Y1 - 2013/9
N2 - Prior to initiating a phase 1 dose escalation trial of the safety and immunogenicity of live, oral, recombinant, attenuated Salmonella enterica serovar Typhi vaccine strains in human subjects, the suitability of conventional blood culture procedures to rapidly and reliably detect the organisms in human blood was investigated. Blood culture specimens, with and without added growth supplements, were inoculated with study organism concentrations ranging from approximately 300 to as few as 1 to 2 CFU/10 ml culture and processed in a Bactec 9240 fluorescent series aerobic blood culture system. All cultures seeded with > 6 CFU and 93% of cultures seeded with ~ 1 to 2 CFU were identified as positive for microbial growth within 44 h of incubation. The results were within the performance standard of ≤ 5 days to detection that is expected for Gram-negative cultures seeded at 10 to 50 CFU/vial. Recovery of test organisms from blood culture was not improved by the addition of supplements, but cultures with added supplements were identified positive an average of 5 h sooner than those without added supplements. Reliable detection of the investigational vaccine strains at < 1 CFU/ml of blood within 2 days in conventional blood culture without added supplements allowed for shortened confinement time of study volunteers without compromising subject safety.
AB - Prior to initiating a phase 1 dose escalation trial of the safety and immunogenicity of live, oral, recombinant, attenuated Salmonella enterica serovar Typhi vaccine strains in human subjects, the suitability of conventional blood culture procedures to rapidly and reliably detect the organisms in human blood was investigated. Blood culture specimens, with and without added growth supplements, were inoculated with study organism concentrations ranging from approximately 300 to as few as 1 to 2 CFU/10 ml culture and processed in a Bactec 9240 fluorescent series aerobic blood culture system. All cultures seeded with > 6 CFU and 93% of cultures seeded with ~ 1 to 2 CFU were identified as positive for microbial growth within 44 h of incubation. The results were within the performance standard of ≤ 5 days to detection that is expected for Gram-negative cultures seeded at 10 to 50 CFU/vial. Recovery of test organisms from blood culture was not improved by the addition of supplements, but cultures with added supplements were identified positive an average of 5 h sooner than those without added supplements. Reliable detection of the investigational vaccine strains at < 1 CFU/ml of blood within 2 days in conventional blood culture without added supplements allowed for shortened confinement time of study volunteers without compromising subject safety.
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U2 - 10.1128/CVI.00331-13
DO - 10.1128/CVI.00331-13
M3 - Article
C2 - 23885029
AN - SCOPUS:84884697875
SN - 1556-6811
VL - 20
SP - 1473
EP - 1478
JO - Clinical and Vaccine Immunology
JF - Clinical and Vaccine Immunology
IS - 9
ER -