El 12 de mayo de 2017 celebramos en la Fundación Ramó Areces una jornada con IS Global y Unitaid sobre enfermedades transmitidas por vectores, como la malaria, entre otras.

1. Malaria Vector Control Priorities
Fredros Okumu, PhD
Ifakara Health Institute, Tanzania
Madrid-May 11th 2017 UNITAID/WHO/IsGlobal Vector Control Meeting

2. Killeen et al 2014

3. + physiologically
resistant mosquitoes

4. By 2000, resistance
had been reported in
more than 100
mosquito species
including more than
50 anopheles
mosquitoes
worldwide
(Hemingway and
Ranson 2000)

5. Itinerant
Rice
Farmers in
Tanzania

6. 0
1
2
3
4
5
6
7
8
9
0
5
10
15
20
25
30
Meannumberofhostseekingmosquitoes
Frequencyofoutdooractivities(Noofpeople
involved)
Cooking
Eating
Watching television
Selling and Buying
Telling stories
Anopheles arabiensis
Anopheles funestus
Matowo et al 2013
Correlation between outdoor activities and biting times of vectors

7. Field entomological techniques will be critical in the fight against residual
vectors
Raymond Shannon 1931

8. The attacking
vectors can be
killed before or
after they feed
5/11/2017
Combining LLINs and IRS against An.
arabiensis
8
Pre feeding
mortality and
post feeding
mortality
Okumu et al 2015

9. Rural South-Eastern Tanzania: Dominant contribution of Anopheles funestus
mosquitoes to ongoing residual transmission, despite their low abundance
relative to Anopheles arabiensis
Kaindoa et al

10. Limited knowledge on Basic Biology and Ecology of disease
vectors

11. Nh
A B
Qh,0 =0.5
Ch=0.8
1-πi,0 =0.5 πi,0 =0.5
1-Ch =0.2
Ch=0.8
Ch=0.8CA,p=0.2
1- Qh,0 = 0.5
A
Attack related survival probability per feeding cycle:
Pγ = 1 – (μh,p CA,p + μh,u (1-CA,p))
Kiware et al., 2012

12. Killeen et al 2014

13. 13
Key Issues
• Insecticide-based interventions
• Outdoor Targeting and Exploiting
Vector Behaviour
• Environmental Management and
Larval Source Management
• Genetic Approaches

14. 14
VECTOR CONTROL | Insecticide Based Interventions
• Twelve insecticide products are currently available for vector control(pyrethroids,
organochlorines, organophosphates, and carbamates); Only pyrethroids for for LLINs.
• Emerging resistance to insecticides in Anopheles mosquitoes threatens to reverse
these gains.
• Innovation to Impact (I2I) was initiated in 2013 aiming to transform the process for
developing and delivering life-saving vector control products for diseases caused by
vector-borne pathogens
• Several combination LLINs are in late-stage development.
• After screening ~4 million compounds, three new insecticides progressed to development;
will take 5–7 years until registration
• For IRS, two new long-lasting formulations now available: a micro-encapsulated
organophosphate, pirimiphos methyl in 2012; and a polymer enhanced suspension of
deltamethrin in 2013.

15. 15
Application Product Insecticide(s)
IRS Phantom Chlorfenapyr (Phase III)
SumiShield Clothianidin (Phase II)
Fludora Fusion Deltamethrin + clothianidin (Phase II)
LLINs DawaPlus 2.0 Deltamethrin coated on polyester
LifeNet Deltamethrin incorporated into polypropylene
MiraNet Alpha-cypermethrin incorporated into polyethylene
Panda Net 2.0 Deltamethrin incorporated into polyethylene
Yahe Deltamethrin coated on polyester
LLINs + PBO Olyset Plus Permethrin + PBO incorporated into polyethylene
PermaNet 3.0 Deltamethrin coated on polyester side panels; deltamethrin + PBO
incorporated into polyethylene (roof)
Veeralin Alpha-cypermethrin and PBO incorporated into polyethylene
Combination
LLINs
Olyset Duo Pyriproxyfen and permethrin incorporated polyethylene
Interceptor G2 Alpha-cypermethrin + chlorfenapyr coated on polyester
Insecticides for IRS under WHOPES evaluation and LLINs in late-stage development

16. 16
VECTOR CONTROL | Outdoor Targeting and Exploiting vector
Behaviour
• Long-standing evidence for Southeast Asia and
South America; and increasing evidence of
outdoor transmission in sub-Saharan Africa.
• Greater understanding of vector behaviour, sugar
feeding, oviposition, mating, dry-season survival,
swarming behaviour, and zooprophylaxis
• Example: all major malaria parasite vectors in
Africa mate in swarms; this facilitates close
targeting either with insecticides or traps.

17. 17
VECTOR CONTROL | Environmental management & Larval
Source Management
• Environmental management, improved housing and
water management, can be highly effective in
specific epidemiological and environmental settings.
• Require further investigation in tropical and
resource-poor settings to establish epidemiological
impact.
• LSM has been highly effective in certain situations,
but is resource-intensive; better definition of
appropriate requirements and approaches needed.

18. 18
VECTOR CONTROL | Genetic Approaches
• There are two main strategies for
genetically modifying mosquito
populations: Population suppression;
and Population alteration or
replacement.
• Genetic approaches now appear
operationally feasible given recent
advances in molecular biology, such as
the efficient genome editing techniques
based on the bacterial CRISPR-
associated protein-9 nuclease (Cas9).
© MIRUS Bio LLC

19. 19
VECTOR CONTROL | Key Challenges
• Insecticides and long-lasting insecticidal nets (LLINs)
• New insecticides and combinations of insecticides to overcome vector resistance
• Non-pyrethroid insecticides for LLINs
• Investigation of new insecticide deployment strategies
• LLINs with improved durability
• Environmental Management
• Formal investigation of larval source management in a greater variety of settings
• Development of long-lasting safe larvicides
• Development of cost-effective and socially acceptable environmental management interventions
• Genetic Approaches
• Development of scalable genetic approaches
• Development of environmentally and socially responsible methods for field testing transgenic organisms
• Exploiting Vector Behaviour
• Novel interventions to target populations and behaviours
• Increased entomological support for key decisions by national malaria programmes