week 1

Question 1

what mosquito behaviours indoors can we investigate

Answer 1

• behaviour at a LLIN
• house entry
• movement in d space
• resting
• arrival at the host

Question 2

what sorts of mosq movements happen at a net

Answer 2

• swooping-dont contact net
• occasional visiting to the net
• frequenct bouncing contacts
• resting on the net

Question 3

what part of a net are mosqs attracted to and why

Answer 3

top of net- attracted to CO2

Question 4

how does an ITN work

Answer 4

human baited trap, mosq has brief contact with net above occupants torso
velocity measurements show mosqs detect nets even unbaited untreated nets, and decelerated prior to contact, to avoid collisions

Question 5

do female aedes aegypti have preferred routes through a home?

Answer 5

aedes attracted to dark colours (simple stimulus)

Question 6

what is a barrier bednet

Answer 6

add barriers near roof of net, different designs.
could expand range of insecticides used on nets
also could be cheaper than PBO nets
could be used on pyrethroid nets with an OP barrier or untreated net with OP barrier

Question 7

what are the limitations of lab tests (cones tubes tunnels)

Answer 7

• not always representative of true LLIN action
• limited insight into slow acting insecticides
• sublethal or delayed (>24hr) effects missed
• behavioural effects not measured

Question 8

what tests can evaluate AIs and LLINs

Answer 8

video cone test
thumb test
room scale tracking

Question 9

what is an emerging VBD

Answer 9

a vbd that spreads into new areas, naive individuals may move to endemic areas, vectors change host preference or new interactions between parasites and hosts develop

Question 10

what is a re-emerging VBD

Answer 10

VBD that reappears in locations it has been controlled in

Question 11

what needs to be shown to associate a vector with disease

Answer 11

1. Demonstration of feeding or other effective contact with the host under natural conditions
2. A convincing biological association in time and/or space of the suspected arthropod species and occurrence of clinical or subclinical infection (asymptomatic) in the host
3. Repeated demonstrations that the arthropod, under natural conditions, harbors the infectious agent in the infective stage. 4.Transmission of the agent under controlled conditions

Question 12

how can you show there is effective contact between vector and host (1)

Answer 12

Evidence of bites- identify all poss vectors, are they zoophilic or anthropophilic

Collect major vectors using traps

Bloodmeal analysis using PCR

Question 13

How to associate vector and host infection (2)

Answer 13

Identify pathogen in patient

Does the disease correspond with reports of increase in vector activity

Question 14

how to show the vector harbours the infection agent in its infective stage

Answer 14

• dissection
• presence of parasites in faeces (triatomines)
• ELISA
• PCR

Question 15

how to show transmission of agent under controlled conditions

Answer 15

• naturally or experimentally infected animal fed on by arthropods
• arthropods forced to feed on uninfected animals after extrinsic incubation period

Question 16

define vector competence

Answer 16

the ability of a vector to transmit a disease: infect, maintain and transmit a pathogen

Question 17

define vectorial capacity

Answer 17

the total number of potentially infectious bites that would arise from all the mosquitoes biting a single perfectly infectious human on a single day

Question 18

what factors affect vectorial capacity

Answer 18

• pathogen receptivity in the vector
• contact with the host
• does vector live long enough to allow full intrinsic incubation of parasite
• freq of feeding
• mobility
• density big enough to sustain transmission
• physiological and behavioural plasticity
• susceptibility to control measures