Development of the VITA ® AFB Diagnostic Kit

The VITA ® AFB Diagnostic Kit has been developed for Vita (Europe) Limited by the Pocket Diagnostics section at the Central Science Laboratory in York , UK . It is designed to provide a rapid on-site diagnosis of American Foulbrood infections in honeybee larvae. The kit is based on similar technology to that of the highly successful home pregnancy test kits and reacts specifically to antibodies associated with the pathogen Paenibacillus larvae var. larvae causing American Foulbrood in honeybees.

The kits are rigorously tested for use in the field, by comparison with standard laboratory tests. Validation of this test kit has been performed at the National Bee Unit of the Central Science Laboratory, York and at other institutes internationally.

The assay principle is represented diagrammatically below:

 

Kit Contents

1x Extraction Bottle (A) containing 5mls of extraction buffer and ball bearings

Contains 0.05% sodium azide as a preservative (see warning below).

1x Test Device (B) in foil pack.

Each pack contains a sachet of silica gel dessicant. Avoid skin contact.

test kit

 

Results kit

 

The device needs to be kept horizontal after addition of the test sample. To achieve this, place device in palm of hand or alternative flat surface.

There is space on the label on the reverse of the device to write details such as

sample identification, date and result. Also on the reverse is a batch number for each device. If problems are encountered with any device please quote this batch number when contacting Vita ( Europe ) Limited.

 

Sampling

Whole or part samples can be used with the extraction bottle. It is recommended that a whole infected larva be used to obtain the best results.

Handling devices:

Each device is disposable. Use only once.

The foil pack should be kept unopened and stored at room temperature (c. 18 - 25 ° C) until required.

Once the foil pack is opened the shelf life of the devices is not guaranteed. It is advisable to use them as soon as possible after opening.

The window of the test device should not be touched.

The devices must be kept dry at all times.

If the device appears damaged, scratched, or marked in any way please contact Vita ( Europe ) Limited.

Read all instructions before using test kits.

CAUTION: This kit contains sodium azide in the extraction buffer, which is toxic. Handle carefully and avoid ingestion and contact with the skin. Sodium azide may form explosive copper or lead azides in plumbing systems. Always dispose of material containing azide by flushing copiously with water.

 

Instructions for Use

(Refer to the Step-by-Step diagrams below)

Development of the VITA ® AFB Diagnostic Kit

 

Extraction

Use the spatula provided to extract a larva with suspicious symptoms.

Unscrew lid from the Extraction Bottle. Use spatula to deposit sample into bottle. Shake vigorously to detach the larva into the buffer.

BEWARE - Bottle contains buffer and sodium azide.

Replace lid tightly and then shake firmly for about 20 seconds, until the sample is thoroughly mixed with the buffer.

 

Testing

Remove a Test Device from foil pack. WARNING Do not touch viewing window.

Unscrew lid of Extraction Bottle and use the supplied pipette to remove a sample from the bottle. For best results remove sample with pipette immediately after shaking, to prevent bacteria from settling out of suspension.

Hold Device horizontally and gently squeeze 2 drops onto the sample well of the device.

Keep device horizontal until extract is absorbed (c. 30 seconds) and a blue dye appears in the viewing window.

Wait until the control line appears (labelled C) and read the result (c.1-3 minutes) Please dispose of your test carefully and help to keep the countryside tidy.

 

Interpretation of Results

After 3 minutes the Control line should be clearly visible in the viewing window of the device. A positive result (two lines show up - both Test and Control, see below) indicates that the target pathogen is present in the test sample, that is that the cell sampled contained infection by American Foulbrood.

A negative result (Control line shows up only, no Test line) indicates that the AFB pathogen has not been detected in the test sample. 

Results

Two blue lines (C&T) indicates a positive result, test performed O.K.

One blue line (C only) indicates a negative result, test performed O.K.

Faint blue T line, strong C line indicates a possible positive, test performed O.K.

 

Please note: As with all diagnostic testing a negative reaction does not necessarily indicate that the target pathogen is absent. A faint or absent line may indicate a low concentration of the pathogen or recent infection. If in doubt repeat with a new device using a fresh sample or repeat in a few days time.

 

One blue line (T only) indicates the test has failed

No lines present indicates the test has failed

Brown C or T lines indicates the test has failed

 

If the test has failed we recommend carrying out another using a new sample from the same original comb with a new device. Should problems persist please contact Vita ( Europe ) Limited on (01256) 473175 or by e-mail web@vita-europe.com.

 

Troubleshooting

 

Problem Cause / Remedy
   
Sample not mixed Inefficient extraction due to sample too large or too small. Try fresh sample or shake more vigorously.
   
No blue dye flow Add an additional drop, one at a time until flow is achieved.
   
No control line visible

Too much sample added; test flooded. Repeat with new device and add only two or three drops.

Flow components exposed to wet or damp. Repeat with new device.

   
Brown lines (not blue) visible

Brown lines are produced from concentrated sample, and not specific pathogen recognition. Repeat with a new, smaller sample.

   
Faint lines Low pathogen concentration low concentration in sample due to sample size too small or sample not shaken long enough or vigorously enough.
   
Damaged Devices/Bottles Please contact Vita directly. Please quote batch number for reference.
   
Lines disappear after a few hours Degradative enzymes in sample have damaged the antibodies. Read tests up until 30 minutes only, do not read any later.

 

Storage

Vita AFB Diagnostic Kits are stable at room temperature and should not be refrigerated or frozen. They should be kept dry and used within a few days once the foil pack has been opened.

 

Conditions of Supply

The tests supplied are designed for the detection and diagnosis of the pathogen stated on the foil pack.

The tests should be used to provide the basis for a presumptive diagnosis. A negative result cannot be taken as evidence of freedom from the specific pathogen under test. If in doubt, repeat the test or submit to a diagnostic laboratory for confirmation.

The extraction solution contains phosphate buffered saline, Tween 20 detergent, sodium azide, casein and EDTA. It should be used only as part of a Vita AFB Diagnostic Kit. Care should be taken to avoid contact with skin and eyes. Store away from children. Not to be taken internally.

This product is for diagnostic use only. It is supplied, and service, information and advice rendered, on the understanding that the customer is solely responsible for determining its suitability for the intended purpose. The entire risk as to the performance of this product is assumed by the buyer. Vita ( Europe ) Limited shall not be liable for any indirect, special or consequential damages of any kind resulting from its use. The sole and exclusive remedy of the customer is limited to the replacement of the goods or the invoice price of the goods.

 
We care for your bees

VITA ® is a registered trademark of Vita (Europe) Limited, 21/23 Wote Street , Basingstoke, Hampshire RG21 7NE , UK .