WASH Cluster – Emergency Training
VC
Vector Control
Module 0
Introduction
VC0
1
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
2
WASH Cluster – Emergency Training
VC
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
3
WASH Cluster – Emergency Training
VC
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
4
WASH Cluster – Emergency Training
VC
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
5
WASH Cluster – Emergency Training
VC
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.
6
WASH Cluster – Emergency Training
VC
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
7
WASH Cluster – Emergency Training
VC
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
8
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
9