VCO_PP_Introduction

WASH Cluster – Emergency Training

VC

Vector Control Module 0 Introduction

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WASH Cluster – Emergency Training

VC

In most humanitarian crises since early 90s the top 5 killers are: • Diarrhoeal diseases (water & VBD borne) • Malaria (VBD) • Measles • Pneumonia • Malnutrition But other parasitic and viral disease may predominate in certain regions VC0

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WASH Cluster – Emergency Training

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The nature of vectors Group discussion activity:

• In small groups, brainstorm types of vectors, and areas of overlap with other sectors (5 minutes) • Discuss in plenary (5 minutes) VC0

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WASH Cluster – Emergency Training

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Disease vectors and their control in emergencies

A disease vector: a carrier/transmitter of disease from person to person A pest or ‘nuisance’ vector: similar, but do not transmit disease VC0

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WASH Cluster – Emergency Training

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Transmission Cycles of Parasitic, Viral & Bacterial VBDs • Many parasites have a single host • Vectors • Arthropods (i.e.) – Mechanical vector (flies) = bacterial dysentery – Biological vector (mosquito) = malaria & dengue • Molluscs (i.e.) - Host vectors (snails) = schistosomiasis

• Hosts • Definite host (in which sexual reproduction occurs) • Intermediate host (larval or asexual stages occur)

• Note: many protozoa are asexual (Leishmania) VC0

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WASH Cluster – Emergency Training

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The Common vectors in emergencies Vector Anophelene Mosquitoes Culicine Mosquitoes Houseflies Cockroaches Lice Bedbugs Ticks Rodent (mites) Rodent (fleas) Rodents

VC0

Diseases Malaria, filariasis. Yellow fever, dengue, viral encephalitis, filariasis. Diarrhoea, dysentery, typhoid fever, conjunctivitis, trachoma. Diarrhoea, dysentery, salmonellosis, cholera. Endemic typhus, pediculosis or severe skin irritation, relapsing fever, trench fever, Severe skin inflammation Rickettsial fever, tularaemia, relapsing fever, viral encephalitis, borreliosis, Lymes disease, scrub typhus. Rickettsial pox, scabies, or spotted fever. Bubonic plague, endemic typhus; Rat bite fever, Lassa fever, leptospirosis or Weil’s disease, salmonellosis, melioidosis.

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WASH Cluster – Emergency Training

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Vectors – their importance The control of vectors is particularly important in emergencies because: • Regular control measures may break down • New breeding grounds may be created (eg floods) • Parasites can invade new/vulnerable communities • Lack of immunity if affected population moving into new areas • Poor sanitation & hygiene in new overcrowded settlements  rapid spread of vectors VC0

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WASH Cluster – Emergency Training

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Sphere Handbook Guidelines on vectors • Vector control standard 1: individual and family protection. All disaster-affected people have the knowledge and the means to protect themselves from disease and nuisance vectors that are likely to represent a significant risk to health or well-being. • Vector control standard 2: physical, environmental and chemical protection measures. The numbers of disease vectors that pose a risk to people's health and nuisance vectors that pose a risk to people's well-being are kept to an acceptable level. VC0

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WASH Cluster – Emergency Training

VC

Common Vectors and their control Must identify vector and understand life cycle for effective control. • Regular assessment needed for immediate 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 VC0

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