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VIDAS LPT - Summary 2012
EUROFINS IPL Nord SAS
–
1 rue du Professeur Calmette
–
59046 LILLE cedex
p 13/14
5.S
pecific equipment or premises
required (see package insert)
Normal configuration and standard microbiology laboratory equipment (Stomacher
type mixer, incubators, etc.)
The equipment required includes:
-
an incubator at 30°C + 1.0°C,
-
an incubator at 37°C + 1.0°C (for the confirmation of positive VIDAS LPT tests)
-
a boiling water bath or a VIDAS Heat&Go system,
-
a VIDAS system
6.
Reagents ready for use or requiring
reconstitution (see package insert)
All the reagents are ready for use.
7.T
raining time for operators with no
previous experience of method
For an operator trained on conventional microbiology techniques, training on the
technique requires less than 1 day.
8. Actual handling time – Flexibility of method with respect to number of samples under analysis
Steps
Mean time for one sample*
Mean time for 30 samples*
Standard
Alternative
Standard
Alternative
Preparation, weighing, dilution Fraser
1/2 and grinding
7
7
90
90
Transfer from Fraser ½ to Fraser
1
/
30
/
Completion of VIDAS LPT test (heat
treatment and passage in system)
/
2
/
50
Isolation of Fraser ½ and Fraser onto
selective media, including plate coding
4
/
50
/
Readings
1
/
20
/
Interpretation of VIDAS LPT results
/
1
5
TOTAL
13 minutes
10 minutes
190 minutes
3h10
145 minutes
2h25
*in minutes
For positive samples, it is necessary to add the time required for confirmations.
For the alternative method, it is necessary to add the time required for the isolation on selective agar, i.e.
approximately 1 minute per sample.
For the alternative method, the confirmations require less time since the presence of characteristic colonies onto
selective agars is enough to confirm the result.
Suspect colonies can also be confirmed by performing rapid tests (API strip) without purification if the colony is
sufficiently isolated.
The benefit of the method particularly lies in the possibility of sorting the negative samples from the suspect
samples and thus simplifying the confirmations, and in the technician time saved when analyzing series of
samples.
9. Time required to obtain results
Stage
Time obtained (in days)
VIDAS
®
LPT
Time obtained (in days)
ISO 11290-1
reference method
Completion of pre-enrichment
J0
J0
Inoculations of enrichment broths
-
J1
Isolation of selective broths on selective agar
/
J1 & J3
Plate reading
/
J2 à J5
Obtaining negative results
(if negative VIDAS LPT test
J1
J5
Obtaining negative results
(if positive VIDAS LPT test and negative confirmation)
J3
J5
Confirmation tests
J1
J2 à J5
Obtaining positive results
(after confirmation)
J2 à J6
J4 à J11
Obtaining positive results
-
Confirmation with reference method tests, including purification
-
Confirmation with isolation on specific agar
J3 à J6
J2
J4 à J11
/