Pre-emptive control measures against MLN spread into West & Central Africa, presented at the International Conference on “MLN Diagnostics and Management in Africa,” organized by AGRA (Alliance for Green Revolution in Africa) and CIMMYT, 12-14 May, 2015

1. Pre-emptive control measures against MLN (MCMV)
spread into West & Central Africa
Lava Kumar
International Institut of Tropical Agriculture (IITA)
PMB 5320, Ibadan, Nigeria
L.kumar@cgiar.org
13 May 2015, MLN workshop, Nairobi, Kenya

2. IITA
Abebe Menkir
Oresanya Damilola
Ogunsanya Patricia
O Opyemi
M Bekunda
I Hoeschle Zeledon
CIMMYT
BM Prasanna
Jumbo Bright
icipe
Sevgan Subramanian
Federal University of
Technology-Mina, Nigeria
MT Salaudeen
Sealian Agricultural Research
Institute, Arusha, Tanzania
Allan Merkie
Yangole Luhenda
Salome Muniss
Team and Acknowledgments

3. -Major diseases in Africa are spread across several countries
-Insufficient coordination, communication and information sharing
are some of the major causes for poor management of diseases
-Fragmented control measures are ineffective against trans-
boundary threats
Introduction
• International alliances improves the coordination of prevention
and control measures against transboundary diseases

4. MLND/MCMV
FoC TR4
Distribution of high priority pathogens in Sub-Saharan Africa
Outbreaks of endemic and introduced pathogens are responsible for
billons of loss of food production

5. Major disease outbreaks since 2000
Risks to West and Central Africa
Banana bacterial wilt Cassava brown streak Banana bunchy top Banana fungal wilt (TR4)

6. Major disease outbreaks since 2000
Distribution in Africa
•Kenya (2012)
•Tanzania (2013)
•Uganda (2013)
•Rwanda (2013)
•Burundi (2013)
•South Sudan (2013)
•DRC (2014)
•Ethiopia (2014)
MCMV

7. Expansion of
outbreaks due to:
•Infected planting
material
•Spread by vectors,
•Practices
Outbreak to epidemic and pandemic
Controlling outbreak at emergence can save billons of US$
Single outbreak
leading to epidemics
and pandemics

8. Lack of awareness Common reasons for pathogens spread
•Lack of surveillance and
emergency response systems
Source: abc.net.au

9. • 725,000 pest (non-indigenous
insects, mites, molluscs, nematodes, plant pathogens and
weeds)
• 62% of intercepted pests were associated with baggage
• 30% were associated with cargo
• 7% were associated with plant propagative material.
• 50,750 in 17 years (ca. 3,000 interceptions per year)
*Source: McCullough et al., 2006, Biological invasions 8: 611-630.
Interception of non-indigenous pests at US ports
1984-2000*
•Two new diseases in African continent since 2011
•Several reports of new spread of existing pathogens within the continent

10. Porous borders
•Difficult to trace pest
entry
•Often legally
exchanged materials
receives blames
•Official border posts in
Nigeria ~42

11. MLN: Ebola of Maize

12. What do we know/have!
•Disease biology (symptomatology)
•Diagnostics
•Virus diversity in infected plants
•Phenotyping facility for germplasm evaluation
•Potential tolerant germplasm
Unknown’s
•Transmission & Epidemiology
•Inoculum survival
•Vector diversity and their role in spread
•Disease distribution
Knowledge & gaps

13. • Delayed initial diagnosis
– Unfamiliar disease symptoms
– Lack of awareness
– Lack of diagnostic capacity
• Once established, difficult to control
• Limited control options (mainly regulatory control)
– Multiple sources of inoculum
• Soil, residues and water
• Seed
• Vectors
Key conclusionsKey conclusions

14. Stopping
further
spread

15. Measures to halt MLN pandemic

16. Pre-emptive control objectives
•Understanding the potential for spread and epidemic
•Identification of strengths, weakness and
development of contingency measures
•Development of coordinated action plan linking
relevant stakeholders
•Strengthening diagnostic capacity
•Awareness on control measures
•Pre-emptive breeding

17. 0
10
20
30
40
50
60
70
0
20
40
60
80
100
120
1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52
t
ha
Tons(x100,000)
Ha(x100,000)
Maize production in Nigeria
(1961 – 2013)*
*FAOStat 2015
0.0
2.0
4.0
1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52
Series1Yield
t/ha
1931 Year 2013
Inception in Nigeria (2014- )

18. •SCMV and MSV detected but not MCMV
•Aphids and thrips are widely distributed
Conducted baseline surveys in major production areas

20. Breeding for MLN Resistance in West African Germplasm
•Evaluation of IITA’s maize inbred lines in MLN phenotyping
facility established by CIMMYT-KARI at Naivasha, Kenya
Pre-emptive breeding

21. 0
20
40
60
80
100
120
Score 1-2 Score 2-3 Score 3-4 Score 4-5 Score >5
Average Early season Late season
Numberofgenotypes
Severity Score
TZM 1723, 1730 and 1746 were found to be most promising (severity rating <2.8)
180 genotypes evaluated in MLN screening facility in Nairobi
Screening of west and central African maize inbred lines against MLN
Pre-emptive breeding

22. On-going…
•Institutional assessment
•Development of regional diagnostic labs

23. Development of diagnostics:
ELISA
Recombinant polyclonal antibodies
against MCMV

24. RT- LAMP
Isothermal diagnostic assays
for field detection of viruses
•MCMV, SCMV and MSV
(individual assays)
•Diagnosis under 30 min
•Visual identification
+ - - + -
MSV - 789bp
MCMV-500bp
SCMV - 203bp
M Inf Inf Hel
Single tuber Multiplex PCR
For simultaneous detection of
all the major maize viruses
Diagnostics

25. Molecular Diagnostics
25
ICT and Diagnostics
Digital surveillance for real time monitoring

26. Conclusions

27. Surveillance and emergency response
•Critical for early recognition of a
problem and timely
implementation of control
measures
•How and by who?
•Challenges?
•Lack of awareness
•Inadequate capacity
•Inadequate coordination
•Inadequate funding
Surveillance systems for early detection and action

28. Surveillance systems for early detection and action
Pre-emptive control and
preparedness (emergency
response)
•Low-priority for several
donors and national programs

29. Education
Communication Monitoring
Sensitive and robust diagnostics tools
Critical to the success of the transboundary disease control
Communication, Cooperation, coordination

30. •Diagnostics are well established
•Simple cost-effective tools to most expensive tools
• Infrastructure maintenance
• Recouping diagnostic reagents
• Retaining well trained staff /augmenting staff skills
• Access to updated knowledge on pathogens
• Knowledge and upkeep of regulatory requirements
• Sustainable funding
Sustained commitment required
to sustain diagnostic labs

31. •Regions around the border
•Intensely farmed areas
•Research organizations
•Seed & planting material
production agencies
•Ports & border posts
Clear targets for surveillance

32. •Disincentives for
reporting new
diseases.
•Encourages non-
compliance.
Issues with
surveillance
and reporting

33. The next epidemic – Lessons from Ebola
“Perhaps the only good news from the tragic Ebola
epidemic in Guinea, Sierra Leone, and Liberia is that it
may serve as a wake-up call: we must prepare for
future epidemics of diseases that may spread”
-Bill Gates
N Engl J Med 372;15