1. VC3A VC WASH Cluster – Emergency Training 1 Vector Control Methods Module 3A Introduction

2. VC3A VC WASH Cluster – Emergency Training 2 Decision to carry out vector Control

3. VC3A VC WASH Cluster – Emergency Training 3 Common Vectors and their control Regular assessment needed for immediate control Must identify vector and understand life cycle for effective control. Distinguish – and prioritise - between disease risk and nuisance Use environmental controls where possible Only use chemical spraying as last resort, as –Frequent use causes resistance –Can be poisonous –Environmentally polluting

4. VC3A VC WASH Cluster – Emergency Training 4 Planning a vector control campaign Strategy –Identify vector with certainty –Determine environmental factors involved –Map breeding sites & population spread –Assess risk of disease epidemic Determine objectives – acceptable levels and control methods Determine indicators by which to measure the impact of the campaign

5. VC3A VC WASH Cluster – Emergency Training 5 Vector control campaign: Strategy Identify vector with certainty Determine environmental factors involved: Breeding sites Feeding areas Map breeding sites & population spread Assess risk of disease epidemic Determine any chemical resistance of vectors Plan areas to be covered by campaign

6. VC3A VC WASH Cluster – Emergency Training 6 Vector control campaign: Objectives Environmental controls alone? Hygiene promotion campaign? Chemical response needed? A combination may be the optimum solution to reduce the risk of epidemics

7. VC3A VC WASH Cluster – Emergency Training 7 Vector control campaign: Indicators Targeted AnimalExample Indicator mosquitoes black-flies bugs sand-flies ticks flies lice fleas scabies / mites number of specimens collected per room (captured with pyrethrum) number of specimens collected per person per night (night-time capture on human bait) number of specimens collected per person per day (daily capture on human bait) percentage of houses infested number of specimens collected per trap (oiled-papers or light traps) number of specimens collected on sweeping cloth number of specimens collected per time unit on a standard grill percentage of persons found positive on inspection number of specimens per trap (light and/or carbon dioxide) percentage of specimens found positive on inspection

8. VC3A VC WASH Cluster – Emergency Training 8 Vector control campaign: Planning the programme Before implementing control measures, ensure: Objectives are clearly defined Control method options are clearly defined Host country regulations & role understood Sufficient resources & personnel Supervision & training requirements met Logistics arranged Role of affected community clarified

9. VC3A VC WASH Cluster – Emergency Training 9 Example vector control campaign Source: UNHCR, 1997.

10. VC3A VC WASH Cluster – Emergency Training 10 Divide area into operational zones small enough to be treated by a team (4-5 people) One worker can use 8-10 hand-sprayers a day, each containing 8 litres of solution With an application rate of 40 ml of solution per m 2, one worker can treat about 1,800 m 2 a day, or 36 dwellings of 50 m 2 each. Example vector control campaign

11. VC3A VC WASH Cluster – Emergency Training 11 Vector control practical Exercise 1: Calculate the amount of permethrin (50% EC formulation) needed to impregnate 200 mosquito nets with a dose of 0.2 g/m2. The net dimensions are 2m height by 2m length, and 1m width, with an overlap band of 0.3m width.(N.B. EC = emulsifiable concentrate, to be diluted with water).

12. VC3A VC WASH Cluster – Emergency Training 12 Vector control practical Exercise 2: In a malaria outbreak in a tented camp area, your cluster has decided to treat all the dwellings with a residual spraying of pyrethroid compound to reduce the mosquito population. You need to spray 1500 shelters with deltamethrin, which is provided in a 2.5% WP (wettable powder) formulation. The shelters have an average surface area of 75m 2. Calculate the amount of deltamethrin and the quantity of water needed. (N.B. 0.04 l/m 2 solution is a standard coverage value for spraying insecticide).

13. VC3A VC WASH Cluster – Emergency Training 13 Summary & conclusions Wrap-up session Outstanding Issues Sources of further information

14. VC3A VC WASH Cluster – Emergency Training 14 Terms for how vectors behave: Anthropophilic: bite humans Zoophilic: bite animals Endophagic: bite indoors Exophagic: bite outdoors Endophilic: rest indoors after a blood meal Exophilic: rest outdoors after a blood meal

15. VC3A VC WASH Cluster – Emergency Training 15 Information needed for design of prevention strategies: Vectors and their behaviourVectors and their behaviour Is there a risk of an outbreak?Is there a risk of an outbreak? Who are the most at risk?Who are the most at risk? Feasibility (security, access, funding, available materials, adequate human resources, local capacity)?Feasibility (security, access, funding, available materials, adequate human resources, local capacity)? People’s behaviour (mobile/fixed, sleep inside/outside etc)?People’s behaviour (mobile/fixed, sleep inside/outside etc)? Type of shelter used?Type of shelter used? Strong preferences/dislikes?Strong preferences/dislikes? Previous experiencesPrevious experiences

16. VC3A VC WASH Cluster – Emergency Training 16 Which intervention is the most cost effective? IRS is much cheaper for one off interventions.IRS is much cheaper for one off interventions. Must repeat IRS every 6-10 months in area of constant, high transmissionMust repeat IRS every 6-10 months in area of constant, high transmission Over 2 years it may be cheaper to use ITNs and the families will have a greater level of control and responsibility.Over 2 years it may be cheaper to use ITNs and the families will have a greater level of control and responsibility. For refugees and IDPs use of insecticide treated plastic sheeting can be effective and economical as it provides shelter and control of malaria mosquitoes and fliesFor refugees and IDPs use of insecticide treated plastic sheeting can be effective and economical as it provides shelter and control of malaria mosquitoes and flies

17. VC3A VC WASH Cluster – Emergency Training 17 Challenges to controlling VBDs in emergencies: Efficacious toolsEfficacious tools Ensuring access to efficacious tools for prevention and treatmentEnsuring access to efficacious tools for prevention and treatment Acceptability - a major key to effectiveness of the toolsAcceptability - a major key to effectiveness of the tools Suitability - there on time & fitSuitability - there on time & fit “Know How” to use correctly“Know How” to use correctly

18. VC3A VC WASH Cluster – Emergency Training 18 Current wisdom for main VBD control Early detection and confirmatory diagnosisEarly detection and confirmatory diagnosis Effective treatmentEffective treatment Intermittent preventative malaria treatment (IPT) of Pregnant womenIntermittent preventative malaria treatment (IPT) of Pregnant women Long lasting insecticide treated nets (LLINs) to protect from vector bites (malaria, filariasis + leishmaniasis)Long lasting insecticide treated nets (LLINs) to protect from vector bites (malaria, filariasis + leishmaniasis) Indoor Residual Spaying (IRS) of dwellings to kill resting insect vectors (malaria and rift valley fever)Indoor Residual Spaying (IRS) of dwellings to kill resting insect vectors (malaria and rift valley fever)

19. VC3A VC WASH Cluster – Emergency Training 19 Larvicide to kill larval forms of vectors in surface water breeding sites (dengue and malaria)Larvicide to kill larval forms of vectors in surface water breeding sites (dengue and malaria) ITPS to provide duel protection (shelter and LL IRS) for displaced families (malaria and flies)ITPS to provide duel protection (shelter and LL IRS) for displaced families (malaria and flies) Tsetse fly traps (sleeping sickness)