Preliminary assessment of bovine trypanosomiasis and its vectors in Santa, Bali and Bafut Sub-Divisions of the, North West Region, Cameroon

A cross-sectional study involving a questionnaire, parasitological examination of cattle and entomological prospection were conducted in the Mezam Division of Cameroon from December 2013 to May 2014 in two seasons for the first time. The objectives were to determine the prevalence of bovine trypanosomiais and its vectors. Peasant farmers ﴾n=95﴿ were interviewed. Standard protocols for parasitological, hematocrit analysis as well as trypanosome identification were used. Acetone baited blue biconical traps ﴾n=5﴿ were used for entomological survey. Questionnaire survey revealed that trypanosomiasis was one of the major health problems affecting animals and a hindrance to agricultural activities. The overall prevalence was 10.3% ﴾31/301﴿. Trypanosome species identified consisted of: T. vivax (58.1%), T. brucei (25.8%), T. congolense (9.6%) and a mix infection (Trypanosoma congolense + Trypanosoma vivax) (6.5%). Vector survey revealed highest fly catch in Bafut subdivision as compared to others with a significant difference ﴾P<0.05﴿. Fly types recorded included: Tabanus 125 (71.4%), Stomoxys 31 (17.7%) and Glossina morsitans submorsitans 19 (10.9%). The overall Apparent Density (AD) was 1.53 fly per trap per day (f/t/d). Therefore, vector transmission and impact of the disease on production is alarming and should not be neglected. Control strategies have to be designed and implemented in Mezam Division in order to eradicate trypanosomiasis and its vectors.© 2016 International Formulae Group. All rights reserved.Keywords: Cattle, trypanosomiasis, Glossina, prevalence, Bafu

CASSAVA MOSAIC DISEASE INCIDENCE AND SEVERITY AND WHITEFLY VECTOR DISTRIBUTION IN GABON

Cassava mosaic disease (CMD) is a major constraint to cassava ( Manihot esculenta Crantz) production in sub-Saharan Africa. The objective of this study was to gain insights into the epidemiology of CMD in cassava production systems in Gabon. An epidemiological survey was conducted throughout Gabon from October 2020 to May 2021 to evaluate the epidemiology of cassava mosaic disease (CMD) in cassava farms. A phytosanitary diagnosis was conducted at each farm, using the harmonised and unified WAVE protocol to assess the incidence and severity of CMD and the abundance of its whitefly vector. All data collected were recorded using WAVE\u2019s mobile application and uploaded into the WAVE Cube data system. The results showed that CMD was present in all farms surveyed (n = 227; 100%), but with a variable incidence rate. At national level, the incidence of CMD was high, with an average of 64.29%. However, incidence differed among regions with 82.22 and 79.20% for Ogooue-Maritime and Nyanga; respectively, but only 40.42% for Estuaire. Woleu-Ntem had the highest mean severity (3.47) and Ogooue-Maritime the lowest (2.64). Overall, incidence and severity differed significantly among regions (P< 0.05). The average abundance was 2.58 whiteflies per plant (w/p), varying between 1.06 (Nyanga) and 5.25 w/p (Estuaire). The use of infected cuttings was the main mode of CMD spread (62.67%). These results highlight the need to identify the viruses responsible for the observed cases of CMD, to sanitise cultivated plant material, and to implement a CMD control strategy in Gabon.La maladie de la mosa\uefque du manioc (CMD) est une contrainte majeure \ue0 la production de manioc (Manihot esculenta Crantz) en Afrique subsaharienne. L\u2019objectif de cette \ue9tude \ue9tait de mieux comprendre l\u2019\ue9pid\ue9miologie de la CMD dans les syst\ue8mes de production de manioc au Gabon. Une enqu\ueate \ue9pid\ue9miologique a \ue9t\ue9 men\ue9e dans tout le Gabon d\u2019Octobre 2020 \ue0 Mai 2021 afin de mieux connaitre l\u2019\ue9pid\ue9miologie de la mosa\uefque du manioc. Un diagnostic phytosanitaire a \ue9t\ue9 fait dans chaque champ prospect\ue9. L\u2019incidence, la s\ue9v\ue9rit\ue9 de la mosa\uefque et l\u2019abondance des mouches blanches vectrices ont \ue9t\ue9 estim\ue9es en utilisant le protocole harmonis\ue9 et unifi\ue9 du programme WAVE. Toutes les donn\ue9es de terrain ont \ue9t\ue9 saisies gr\ue2ce \ue0 l\u2019application mobile de WAVE puis stock\ue9es dans le gestionnaire de donn\ue9es de WAVE, le Cube. Les r\ue9sultats de cette \ue9tude ont montr\ue9 que la mosa\uefque du manioc \ue9tait pr\ue9sente dans toutes les zones prospect\ue9es (n = 227; 100%), avec une incidence variable. Au niveau national, l\u2019incidence de la CMD \ue9tait \ue9lev\ue9e, avec une moyenne de 64,29% pour une s\ue9v\ue9rit\ue9 moyenne de 3,16. Cette incidence varie entre les provinces avec respectivement 82,22% et 79,20% pour l\u2019Ogoou\ue9-Maritime et la Nyanga, mais seulement, 40,42% pour l\u2019Estuaire. La r\ue9gion du Woleu-Ntem a pr\ue9sent\ue9 la plus grande s\ue9v\ue9rit\ue9 moyenne (3,47) et l\u2019Ogoou\ue9-Maritime, la plus faible moyenne (2,64). L\u2019incidence et la s\ue9v\ue9rit\ue9 ont diff\ue9r\ue9 significativement entre les r\ue9gions (P< 0,05). L\u2019abondance moyenne des mouches blanches \ue9tait de 2,58 mouches/plante (m/p). Cette abondance a oscill\ue9 entre 1,06 m/p (Nyanga) et 5,25 m/p (Estuaire). L\u2019utilisation des boutures de manioc infect\ue9es est le principal mode de propagation de la CMD (62,67%). Ces r\ue9sultats pr\ue9liminaires mettent en exergue la n\ue9cessit\ue9 imp\ue9rieuse d\u2019identifier les virus responsables des cas de CMD observ\ue9s, d\u2019assainir le mat\ue9riel v\ue9g\ue9tal cultiv\ue9 et de mettre en place une strat\ue9gie de contr\uf4le de la CMD au Gabon