des petits ruminants virus in West Africa:

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Regional evolutionary dynamics of peste

des petits ruminants virus in West Africa:

influence of livestock trade

Arnaud Bataille Cirad-INRA

Unit for Control of Emerging and Exotic Animal Diseases Montpellier, France P . Dugu é © Ci rad

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Peste des Petits Ruminants (PPR)

 Most widespread and devastating infectious disease of

domestic small ruminants (goats, sheep)

 Camels and some wild ruminants also susceptible

 High economic impact and food security threat

 New target for global eradication (FAO/OIE, 2015)

1940-55 1972-89 1990-2010 2011-14 pictures: H. Salami Georgia 2016

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Peste des Petits Ruminants virus (PPRV)

 Envelopped, single-stranded negative-sense RNA virus

(genus Morbillivirus)

 ~16kb genome coding for 6 structural and 2 non-structural

proteins

(4)

 Four distinct phylogenetic lineages

 Lineage IV spreading from Asia to Africa, L-II replacing L-I

Lineage I Lineage II Lineage III Lineage IV

figure: Libeau et al. (2014)

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PPRV phylodynamics and livestock trade

 PPR transmission and spread linked to livestock trade

 Need for better understanding of regional virus

transmission dynamics for efficient control and eradication

 Can virus phylodynamics be correlated to animal trade?

?

Small ruminant market trade network in Mauritania and Senegal

figure: Baron et al. (2016)

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PPRV endemic transmission in West Africa

 Sampling of PPRV in Senegal (N=41) and neighbouring

countries (N=14) in 2010-2014 Mauritania Mali Senegal Guinea 2 7 3 2 2 6 3 2 2 2 2 2 N Positive sample N positive samples Louga Matam Tambacounda Kédougou Kolda Kaolack Fatick Thiès Dakar

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PPRV lineage II (PPRV-II) in West Africa

 Sequencing of 255bp of N gene: 54/55 samples of PPRV-II

 One sample of lineage I obtained in Mali ( )

Lineage I Lineage II Lineage III Lineage IV Our samples

Maximum Likelihood tree (<50% bootstrap support)

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PPRV lineage II (PPRV-II) in West Africa

Senegal* Guinea* Mauritania* Mali* Sierra Leone Benin (*samples from this study) Burkina F./Mali*/Iv. C. Ghana/Nigeria/Benin Nigeria-Benin (1969-75) Ghana-Nigeria (1976-78) Maximum Likelihood tree (<50%

bootstrap support)

 Phylogeny of PPRV-II based on N gene (255bp)

• Highly informative

• Complex phylogeny with

multiple clusters

• Mali and Benin with highest

diversity

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Transmission dynamics of PPRV-II

 PPRV-II phylogeny (N and H genes) in Senegal and

neighbours to identify of transmission clusters

Louga Matam Tambacounda Kedougou Kolda Kaolack Fatick Thiès Dakar Mekhe Joal Mali 2014

Maximum Likelihood tree (<50% bootstrap support) Ma Da Ta Da Da Lo Fa Da Jo Th Th Fa Me Ma Da Me _Fa Ta Ka _Ka Ka Ta Ma Ko/Ta Ma Ke Ke Th Ko Ko Da Me Clu1 Clu2 Clu3 Clu4 Clu5 Clu6 Clu7 Guinée 2013 Mauritanie 2012

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Association with animal trade

Market importance Type

Transboundary Local Regional hub Intermediary Consumption Flow importance

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Association with animal trade

Transboundary Local Regional hub Intermediary Consumption Flow importance Clu1 Figure: Cesaro et al., 2010

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Association with animal trade

Transboundary Local Regional hub Intermediary Consumption Flow importance Clu4

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Association with animal trade

Transboundary Local Regional hub Intermediary Consumption Flow importance Clu3 Figure: Cesaro et al., 2010

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Association with animal trade

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Association with animal trade

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Association with animal trade

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 Quantitative data on animal movement (from national veterinary services) translated to Social Network Data

 Linear models: genetic distance ~ geo distance +

environmental variables + SNA

Animal movement

Goat density

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Conclusions

 Lineage II predominant, but lineage I circulating in Mali

 Complex phylogeography of lineage II retrieved with short

N gene sequences

 Phylogenetic analyses of PPRV-II confirm frequent

movement of virus within Senegal and across countries

 Movements follow patterns of livestock trade, including

those associated with transhumance

 Quantitative analysis of genetic and trade data could

provide guidance on important targets for control and eradication effort

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Acknowledgements

 Habib Salami1,2,3_{: sample collection, sequencing, data analysis}

 Caroline Coste1,2_{: SNA and sequence data analysis}

 Renaud Lancelot1,2_{: SNA data analysis, supervision}

 Olivier Kwiatek1,2_{Geneviève Libeau}1,2 _{: lab work, supervision}

 Moustapha Lo3_{, Ismaïla Seck}4_{, Mariam Diop}3_{, Ahmed Bezeid El}

Mamy5_{, Ahmed Salem El Arbi}6_{, Lancéï Kaba}7_{, Mamadou}

Niang8_{: sampling and livestock trade data collection}

1 _{CIRAD, UMR CMAEE, Montpellier, France;}2_{INRA, UMR CMAEE, Montpellier, France;}3

ISRA/LNERV, Dakar, Senegal; 4 _{Direction des Services Vétérinaires, Dakar, Senegal ;}5 _CNERV,

Nouakchott, Mauritania; 6 _{Ministère du Développement rural, Services Vétérinaires, Nouakchott,}