Quick insights
- WHO Cone Test is a standardized laboratory method used to evaluate the efficacy of insecticide-treated surfaces and materials against mosquitos
- Mosquitoes were exposed to the treated materials for a specified time period to measure Knockdown rates (KD60) and mortality rates (M24).
- Scope of testing under WHO Cone Test include insecticide-treated nets, residual sprays, wall coatings, and impregnated textiles
- Major factors that can influence test results include mosquito species, exposure time, temperature, and humidity conditions
- WHO Cone Test provides controlled efficacy data, making it important for product validation, regulatory submissions, and vector control research programs.
Summary
The WHO Cone Test is designed to evaluate the effectiveness of insecticide-treated surfaces and materials. The method measures mosquito knockdown and mortality after controlled exposure to treated materials such as bed nets, wall coatings, impregnated textiles, and insecticidal surfaces. Results are expressed as KD60 and M24 values meaning knockdown at 60 minutes and mortality after 24 hours observation period.
What Is the WHO Cone Test?
The WHO Cone Test is a laboratory bioassay developed under WHO vector control guidelines to determine the biological activity of insecticide applied on treated surfaces and materials.
Why WHO Cone Test Matters in Vector Control
Mosquito-borne diseases continue to remain a major public health threat worldwide, increasing the need for effective vector control products and strategies. The WHO Cone Test ensures that insecticide-treated materials and mosquito control products deliver proven efficacy against disease-carrying mosquitoes under controlled laboratory conditions.
By evaluating mosquito knockdown and mortality rates, the test supports the development of reliable solutions such as insecticide-treated nets, residual sprays, treated textiles, and coated surfaces used in vector control programs.
Why Is the WHO Cone Test Important?
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Helps to verify product insecticidal efficacy – The test confirms whether mosquito control products are able to deliver measurable insecticidal effects.
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Supports regulatory submissions and performance claims – WHO Cone Test data is used by the manufacturers during product registration as a supporting evidence for product performance
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Allows product comparison – Different formulations, coatings, and treated fabrics can be compared under standardized conditions.
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Assesses residual performance – WHO Cone test guidelines also help to check residual performance of products after washing, aging, or environmental exposure.
Products Commonly Tested Using WHO Cone Test
- Insecticide-Treated Nets (ITNs)
- Wall paints,
- Sprays,
- Residual surface treatments
WHO Cone Test Methodology
- A standard WHO cone is fixed onto the test surface.
- A fixed number of female mosquitoes is introduced into the cone using an aspirator.
- Mosquitoes are exposed to the treated surface for a specified time period
- After completion of exposure period, knock-down rate is assessed.
- In the next step, mosquitoes are transferred to paper cups containing with sucrose solution and kept in the insectary under controlled conditions maintained
- After a 24 h exposure period, mortality rates are observed to assess any delayed mortality.
Important test parameters
| Test parameters | Details |
| Mosquito Species | Anopheles, Aedes, or Culex mosquitoes (as per protocol) |
| Mosquito age | 3-5 day old |
| Temperature | 27 ยฑ 2ยฐC |
| Relative humidity | U 80 ยฑ 20% RH |
Understanding WHO Cone Test Results
What Is KD60?
KD60 is the percentage of mosquitoes knocked down within 60 min after exposure to the insecticide treated surfaces. Knockdown means the mosquitoes are immobilized or unable to fly normally due to the insecticide. This parameter helps to understand the instantaneous effect of the product on mosquitoes.
What Is 24-Hour Mortality?
24-hour mortality measures the percentage of mosquitoes that die within 24 hours after the exposure period and holding time under controlled conditions.
Assessing mortality rate is a parameter while testing insecticidal properties of products. Some products may show immediate knockdown effects , but this effect can be temporary, and resistant mosquitoes can recover and continue to transmit disease.
For this reason, 24-hour mortality is seen as an important parameter in mosquito control product testing, allowing researchers to evaluate true product efficacy and long term vector control performance.
What is wash resistance study in WHO cone testing?
Wash resistance study is done to evaluate whether insecticide treated fabrics maintain effectiveness after repeated washing and artificial aging.
In this study, treated textile samples undergo defined wash cycles followed by WHO Cone bioassays to assess mosquito knockdown and 24-hour mortality. The purpose is to know durability of bioefficacy throughout the intended useful life of the product.
WHO Cone Test vs Tunnel Test
| Parameter | WHO Cone Test | Tunnel Test |
| Exposure Type | Forced contact | Free-flight exposure |
| Test Duration | Short exposure | Longer behavioral exposure |
| Main Endpoint | Knockdown and mortality | Blood-feeding inhibition and mortality |
| Product Type | Treated surfaces and nets | Nets and repellent materials |
| Real-World Simulation | Moderate | Higher |
Tunnel tests are often used when products rely heavily on repellency or require longer exposure times.
WHO Cone Test vs Arm-in-Cage Test
| Test Parameter | WHO Cone Test | Arm-in-Cage Test |
| Human Volunteers | Not required | Required |
| Product Type | Insecticide treated materials | Topical repellents and impregnated textiles |
| Results interpretation | Mortality and knockdown | Complete Protection Time (CPT) |
| Exposure Method | Surface contact | Mosquito landing and biting on volunteer forearm treated with product |
Factors that can affect WHO Cone test results
There are several factors that can affect accuracy and reproducibility of the WHO Cone test results. Small variations in testing conditions may affect mosquito knockdown and mortality.
Some of the main factors are:
- Mosquito species/strains used for testing
- Age and feeding condition of mosquitoes
- Temperature and relative humidity during the test
- Uniformity of insecticide treatment on the test surface
- Resistance to insecticides in mosquito populations
Need reliable efficacy data for your mosquito control products?
Need reliable efficacy data for your mosquito control products? The WHO Cone Test helps verify the performance of insecticides treated textiles, coatings, sprays, and insecticidal surfaces under standardized conditions.
At Microbe Investigation Switzerland (MIS), we provide scientifically validated testing services to help manufacturers evaluate the efficacy of mosquito control products by assessing knockdown and mortality rates.
For more details, contact our experts now
Read more article related to mosquito control products –
FAQs
1. What is the difference between knockdown and mortality?
Knockdown refers to mosquitoes becoming immobilized or unable to fly after exposure to treated insecticide surfaces, while mortality measures the mosquitoes that die after the 24 hours observation period.
2. Why are female mosquitoes used in WHO Cone Tests?
Female mosquitoes are used for WHO Cone Test because they are responsible for blood feeding and disease transmission.
3. Can WHO Cone Tests evaluate wash durability?
Yes, WHO Cone Tests can assess whether insecticide-treated fabrics retain mosquito control efficacy after repeated washing and aging cycles.
4. What is forced-contact exposure?
Forced-contact exposure means mosquitoes are confined inside the cone and made to remain in direct contact with the treated surface during the exposure period.
5. Are WHO Cone Tests used for WHO prequalification programs?
Yes, WHO Cone Tests are commonly used to generate efficacy data for insecticide-treated products evaluated under WHO vector control and prequalification programs.
6. Which mosquitoes are commonly used in WHO Cone Test?
Common mosquito species include Aedes, Anopheles, and Culex mosquitoes.
7. What does KD60 mean in WHO Cone Test?
KD60 refers to the percentage of mosquitoes knocked down 60 minutes after exposure to the treated surface.
8. What products can be tested using WHO Cone Test?
Products include insecticide-treated nets, wall coatings, treated textiles, sprays, and residual insecticidal surfaces.
