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

IITAAbebe MenkirOresanya DamilolaOgunsanya PatriciaO OpyemiM BekundaI Hoeschle Zeledon

CIMMYTBM PrasannaJumbo Bright

icipeSevgan Subramanian

Federal University of Technology-Mina, NigeriaMT Salaudeen

Sealian Agricultural Research Institute, Arusha, TanzaniaAllan MerkieYangole LuhendaSalome Muniss

Team and Acknowledgments

-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

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

Major disease outbreaks since 2000Risks to West and Central Africa

Banana bacterial wilt Cassava brown streak Banana bunchy top Banana fungal wilt (TR4)

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

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

Lack of awareness Common reasons for pathogens spread

•Lack of surveillance and emergency response systems

Source: abc.net.au

• 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 ports1984-2000*

•Two new diseases in African continent since 2011

•Several reports of new spread of existing pathogens within the continent

Porous borders

•Difficult to trace pest entry

•Often legally exchanged materials receives blames

•Official border posts in Nigeria ~42

MLN: Ebola of Maize

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

• 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

Stopping further spread

Measures to halt MLN pandemic

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

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020406080

100120

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52

tha

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(x10

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Maize production in Nigeria (1961 – 2013)*

*FAOStat 2015

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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- )

•SCMV and MSV detected but not MCMV•Aphids and thrips are widely distributed

Conducted baseline surveys in major production areas

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

020406080

100120

Score 1-2 Score 2-3 Score 3-4 Score 4-5 Score >5

Average Early season Late season

Num

ber o

f gen

otyp

es

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

On-going…

•Institutional assessment

•Development of regional diagnostic labs

Development of diagnostics:ELISA

Recombinant polyclonal antibodies against MCMV

RT- LAMP Isothermal diagnostic assays for field detection of viruses

•MCMV, SCMV and MSV (individual assays)•Diagnosis under 30 min•Visual identification

+ - - + -MSV - 789bpMCMV-500bp

SCMV - 203bp

M Inf Inf Hel

Single tuber Multiplex PCRFor simultaneous detection of

all the major maize viruses

Diagnostics

Molecular Diagnostics

25

ICT and DiagnosticsDigital surveillance for real time monitoring

Conclusions

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

Surveillance systems for early detection and action

Pre-emptive control and preparedness (emergency response)

•Low-priority for several donors and national programs

Education

Communication Monitoring

Sensitive and robust diagnostics tools

Critical to the success of the transboundary disease control

Communication, Cooperation, coordination

•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

•Regions around the border

•Intensely farmed areas

•Research organizations

•Seed & planting material production agencies

•Ports & border posts

Clear targets for surveillance

•Disincentives for reporting new diseases.

•Encourages non-compliance.

Issues with surveillance and reporting

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