Limits...
Culicoides (Diptera: Ceratopogonidae) midges, the vectors of African horse sickness virus--a host/vector contact study in the Niayes area of Senegal.

Fall M, Diarra M, Fall AG, Balenghien T, Seck MT, Bouyer J, Garros C, Gimonneau G, Allène X, Mall I, Delécolle JC, Rakotoarivony I, Bakhoum MT, Dusom AM, Ndao M, Konaté L, Faye O, Baldet T - Parasit Vectors (2015)

Bottom Line: The monthly variation in host/vector contact was determined in the Niayes area, Senegal, an area which was severely affected by the 2007 outbreak of AHS.Nineteen of the 41 species collected were new distribution records for Senegal.This increased the number of described Culicoides species found in Senegal to 53.

View Article: PubMed Central - PubMed

Affiliation: ISRA, Laboratoire National de l'Elevage et de Recherches Vétérinaires, Route Front de Terre, Dakar, Senegal. moussafall08@yahoo.fr.

ABSTRACT

Background: African horse sickness (AHS) is an equine disease endemic to Senegal. The African horse sickness virus (AHSV) is transmitted to the mammalian hosts by midges of the Culicoides Latreille genus. During the last epizootic outbreak of AHS in Senegal in 2007, 1,169 horses died from this disease entailing an estimated cost of 1.4 million euros. In spite of the serious animal health and economic implications of AHS, very little is known about determinants involved in transmission such as contact between horses and the Culicoides species suspected of being its vectors.

Methods: The monthly variation in host/vector contact was determined in the Niayes area, Senegal, an area which was severely affected by the 2007 outbreak of AHS. A horse-baited trap and two suction light traps (OVI type) were set up at each of five sites for three consecutive nights every month for one year.

Results: Of 254,338 Culicoides midges collected 209,543 (82.4%) were female and 44,795 (17.6%) male. Nineteen of the 41 species collected were new distribution records for Senegal. This increased the number of described Culicoides species found in Senegal to 53. Only 19 species, of the 41 species found in light trap, were collected in the horse-baited trap (23,669 specimens) largely dominated by Culicoides oxystoma (22,300 specimens, i.e. 94.2%) followed by Culicoides imicola (482 specimens, i.e. 2.0%) and Culicoides kingi (446 specimens, i.e. 1.9%).

Conclusions: Culicoides oxystoma should be considered as a potential vector of AHSV in the Niayes area of Senegal due to its abundance on horses and its role in the transmission of other Culicoides-borne viruses.

Show MeSH

Related in: MedlinePlus

Description of traps used (A: horse-baited trap; B: light trap) to collect Culicoides at 5 sites in the Niayes area in Senegal from July 2011 to October 2012.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4307892&req=5

Fig2: Description of traps used (A: horse-baited trap; B: light trap) to collect Culicoides at 5 sites in the Niayes area in Senegal from July 2011 to October 2012.

Mentions: To assess vector/host contact, Culicoides were collected using a horse-baited trap identical to the one used by Fall et al. for entomological investigations of mosquitoes’ vectors of West Nile fever [23,24] (Figure 2A). In parallel, two light traps of the OVI (Onderstepoort Veterinary Institute) type were operated to compare host-baited collections with this more widely used Culicoides trapping method [25,26] (Figure 2B). The horse-baited trap consists of net boxes (3.5 m × 2.5 m × 2.5 m, with mesh of 1.5 mm × 0.3 mm) with an open space of 15 cm from the ground allowing Culicoides to enter, to engorge or not on horse, and avoiding the escape of trapped midges. Both sampling methods were used at each of the five sites for three consecutive nights per month from July 2011 to June 2012 at Parc Hann, Mbao, Thies and Pout sites and from November 2011 to October 2012 at Niague.Figure 2


Culicoides (Diptera: Ceratopogonidae) midges, the vectors of African horse sickness virus--a host/vector contact study in the Niayes area of Senegal.

Fall M, Diarra M, Fall AG, Balenghien T, Seck MT, Bouyer J, Garros C, Gimonneau G, Allène X, Mall I, Delécolle JC, Rakotoarivony I, Bakhoum MT, Dusom AM, Ndao M, Konaté L, Faye O, Baldet T - Parasit Vectors (2015)

Description of traps used (A: horse-baited trap; B: light trap) to collect Culicoides at 5 sites in the Niayes area in Senegal from July 2011 to October 2012.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4307892&req=5

Fig2: Description of traps used (A: horse-baited trap; B: light trap) to collect Culicoides at 5 sites in the Niayes area in Senegal from July 2011 to October 2012.
Mentions: To assess vector/host contact, Culicoides were collected using a horse-baited trap identical to the one used by Fall et al. for entomological investigations of mosquitoes’ vectors of West Nile fever [23,24] (Figure 2A). In parallel, two light traps of the OVI (Onderstepoort Veterinary Institute) type were operated to compare host-baited collections with this more widely used Culicoides trapping method [25,26] (Figure 2B). The horse-baited trap consists of net boxes (3.5 m × 2.5 m × 2.5 m, with mesh of 1.5 mm × 0.3 mm) with an open space of 15 cm from the ground allowing Culicoides to enter, to engorge or not on horse, and avoiding the escape of trapped midges. Both sampling methods were used at each of the five sites for three consecutive nights per month from July 2011 to June 2012 at Parc Hann, Mbao, Thies and Pout sites and from November 2011 to October 2012 at Niague.Figure 2

Bottom Line: The monthly variation in host/vector contact was determined in the Niayes area, Senegal, an area which was severely affected by the 2007 outbreak of AHS.Nineteen of the 41 species collected were new distribution records for Senegal.This increased the number of described Culicoides species found in Senegal to 53.

View Article: PubMed Central - PubMed

Affiliation: ISRA, Laboratoire National de l'Elevage et de Recherches Vétérinaires, Route Front de Terre, Dakar, Senegal. moussafall08@yahoo.fr.

ABSTRACT

Background: African horse sickness (AHS) is an equine disease endemic to Senegal. The African horse sickness virus (AHSV) is transmitted to the mammalian hosts by midges of the Culicoides Latreille genus. During the last epizootic outbreak of AHS in Senegal in 2007, 1,169 horses died from this disease entailing an estimated cost of 1.4 million euros. In spite of the serious animal health and economic implications of AHS, very little is known about determinants involved in transmission such as contact between horses and the Culicoides species suspected of being its vectors.

Methods: The monthly variation in host/vector contact was determined in the Niayes area, Senegal, an area which was severely affected by the 2007 outbreak of AHS. A horse-baited trap and two suction light traps (OVI type) were set up at each of five sites for three consecutive nights every month for one year.

Results: Of 254,338 Culicoides midges collected 209,543 (82.4%) were female and 44,795 (17.6%) male. Nineteen of the 41 species collected were new distribution records for Senegal. This increased the number of described Culicoides species found in Senegal to 53. Only 19 species, of the 41 species found in light trap, were collected in the horse-baited trap (23,669 specimens) largely dominated by Culicoides oxystoma (22,300 specimens, i.e. 94.2%) followed by Culicoides imicola (482 specimens, i.e. 2.0%) and Culicoides kingi (446 specimens, i.e. 1.9%).

Conclusions: Culicoides oxystoma should be considered as a potential vector of AHSV in the Niayes area of Senegal due to its abundance on horses and its role in the transmission of other Culicoides-borne viruses.

Show MeSH
Related in: MedlinePlus