TY - JOUR
T1 - Principles of some novel rapid dipstick methods for detection and characterization of verotoxigenic Escherichia coli
AU - Aldus, C.F.
AU - van Amerongen, A.
AU - Ariens, R.M.C.
AU - Peck, M.W.
AU - Wichers, J.H.
AU - Wyatt, G.M.
PY - 2003
Y1 - 2003
N2 - Aims: The verotoxigenic Escherichia coli (VTEC) serotype most commonly associated with verotoxin (VT) production is O157:H7, but other serotypes have also been implicated in food-borne illness. These serotypes exhibit much greater genetic and biochemical diversity than E. coli O157:H7, making screening for all VTEC difficult. Here we describe development and testing of novel multi-analyte antibody-based dipstick methods for presumptive detection of VTEC cells and VTs, including non-O157 serotypes. Methods and Results: The dipsticks are formatted as paddle-style and lateral flow devices. Test materials included raw milk, minced beef, apple juice and salami, spiked with VTEC. Prototype paddle dipsticks gave 47 of 48 E. coli O157-positive samples correct, and, simultaneously, 27 of 31 O26-positive samples correct, across the four food types. Prototype lateral flow dipsticks gave 12 of 12 E. coli O157-positive milk samples correct and, simultaneously, 28 of 28 positive VT samples correct. Conclusions: This work demonstrates that simple and rapid detection of more than one VTEC characteristic (toxin production and type, serogroup) is possible in a single dipstick test device, directly from a food enrichment culture. Significance and Impact of the Study: The development of simple easy-to-use rapid methods for simultaneous detection and preliminary characterization of VTEC will enable the risk presented by all VTEC to be more thoroughly assessed (e.g. in surveillance studies, outbreak investigations).
AB - Aims: The verotoxigenic Escherichia coli (VTEC) serotype most commonly associated with verotoxin (VT) production is O157:H7, but other serotypes have also been implicated in food-borne illness. These serotypes exhibit much greater genetic and biochemical diversity than E. coli O157:H7, making screening for all VTEC difficult. Here we describe development and testing of novel multi-analyte antibody-based dipstick methods for presumptive detection of VTEC cells and VTs, including non-O157 serotypes. Methods and Results: The dipsticks are formatted as paddle-style and lateral flow devices. Test materials included raw milk, minced beef, apple juice and salami, spiked with VTEC. Prototype paddle dipsticks gave 47 of 48 E. coli O157-positive samples correct, and, simultaneously, 27 of 31 O26-positive samples correct, across the four food types. Prototype lateral flow dipsticks gave 12 of 12 E. coli O157-positive milk samples correct and, simultaneously, 28 of 28 positive VT samples correct. Conclusions: This work demonstrates that simple and rapid detection of more than one VTEC characteristic (toxin production and type, serogroup) is possible in a single dipstick test device, directly from a food enrichment culture. Significance and Impact of the Study: The development of simple easy-to-use rapid methods for simultaneous detection and preliminary characterization of VTEC will enable the risk presented by all VTEC to be more thoroughly assessed (e.g. in surveillance studies, outbreak investigations).
KW - shiga-like toxin
KW - monoclonal-antibodies
KW - food
U2 - 10.1046/j.1365-2672.2003.01989.x
DO - 10.1046/j.1365-2672.2003.01989.x
M3 - Article
SN - 1364-5072
VL - 95
SP - 380
EP - 389
JO - Journal of Applied Microbiology
JF - Journal of Applied Microbiology
IS - 2
ER -