WHO Tube Test

World Health Organization (WHO)
Mosquito Knockdown Tube Test

Published in: Test procedures for insecticide resistance monitoring in malaria vector mosquitoes, Second edition, World Health Organization 2016


WHO tube test

  1. WHO holding tubes are attached to separate sliding gates and left in the closed position.
  2. Female mosquitoes (unfed, aged 3-5 days old) are aspirated in batches of 20-25 into each of the holding tubes.  The tubes are then left in an upright position for 1 hour to allow the mosquitoes to acclimatize.
  3. Separate exposure tubes are then lined with insecticide treated materials (12cm x 15cm) and held into position with copper spring-wire clips.  Tubes are then labeled with corresponding treatment levels or wash increments being tested.
  4. Once mosquitoes are acclimatized, the exposure tubes are attached to the other side of the gates and sliders are moved to the open position.  Mosquitoes are then gently blown from the holding tubes over to the exposure tubes and slider once again closed.
  5. Mosquitoes are kept in the exposure tubes in a vertical position for 1 hour.
  6. After 1 hour, sliders are once again opened and mosquitoes are gently blown back over to holding tubes and slider closed.  
  7. Exposure tubes are removed and knockdown is recorded in holding tubes.
  8. Cotton-wool soaked in 10% glucose solution is placed on the mesh screen end of the holding tubes to allow mosquitoes to feed.
  9. Mosquitoes are kept in the holding tubes for 24 hours in a humidity chamber (conditions 25C +/- 2C and 80% relative humidity) for recovery.
  10. At the end of recovery period the number of knockdown mosquitoes is once again recorded.

Adult mosquitoes are considered to be alive if they are able to fly, regardless of the number of legs remaining.  A mosquito is classified as knocked down if it is immobile or unable to stand or take off.

German Army Delivery Specification TL 8305-0331
Mosquito Knockdown Tube Test using standard WHO-Tube

Published by: The German Federal Office of Defense Technology and Procurement, Vektorenschutzausrüstung für textile Flächengebilde – July 2016

WHO tube test on 0 and 100 wash textile samples

  1. WHO holding tubes are attached to separate sliding gates and left in the closed position.
  2. Female mosquitoes (unfed, aged 3-5 days old) are aspirated in batches of 10 into each of the holding tubes.  The tubes are then left in an upright position for to allow the mosquitoes to acclimatize.
  3. Separate exposure tubes are then lined with insecticide treated materials (12cm x 15cm) and held into position with copper spring-wire clips.  Tubes are then labeled with corresponding treatment levels or wash increments being tested.
  4. Once mosquitoes are acclimatized, the exposure tubes are attached to the other side of the gates and sliders are moved to the open position.  Mosquitoes are then gently blown from the holding tubes over to the exposure tubes and slider once again closed.
  5. Knockdown of the first, fifth and all mosquitoes is documented.
  6. Knockdown of all 10 mosquitoes must occur within 71.5 minutes on a 100 washed sample for a passing grade.
WHO Mosquito Knockdown Tube Test Chart