Location: Foreign Animal Disease Research2013 Annual Report
1a. Objectives (from AD-416):
Transboundary animal diseases such as Foot-and-Mouth Disease (FMD) limit livestock production capabilities and restrict trade. In developing countries, such as Cameroon, food insecurity poses a significant hindrance to the nation’s economy. There is a need to understand the ecology of FMD circulating in Cameroon, to improve diagnostic capabilities and tailor vaccines to those strains currently circulating in an effort to control and begin control of the disease. This research project leverages current collaborative research activities between ARS, PIADC and Ohio State University that are aimed at gaining an understanding of the ecology of infectious animal diseases in the Chad basin, including FMD, which is currently being carried out in collaboration with the Laboratoire National Veterinaire (LANAVET) (Cameroon). Specific objectives of this collaborative research project between ARS, PIADC and LANAVET include: 1. Establish a demonstration surveillance system in the North, Far North and Adamaoua regions, where the cattle population is greatest, to determine the clinical and subclinical strains of FMDV circulating in specific region Cameroon. 2. Characterize the basic epidemiological factors influencing the circulation of FMDV in that region. 3. Genetically and antigenically characterize FMDV strains and determine their relationship to vaccine strains. 4. Provide the basic information necessary to support the progressive control of FMD in Cameroon.
1b. Approach (from AD-416):
1. Establish a surveillance system to determine the clinical and subclinical strains of FMDV circulating in the Northern Regions of Cameroon. A sampling protocol will be developed based on previously identified areas where FMD is highly prevalent. Specific herds will be identified and sampled during and between clinical outbreaks in a longitudinal study to determine the currently circulating topotypes. 2. Characterize the basic epidemiological factors influencing the circulation of FMDV. To identify the rate of infection in the different regions and animal populations, serological surveys for non-structural protein antibodies and probang testing will be conducted in various herds represent different production systems in Cameroon. 3. Genetically and antigenically characterize FMDV strains and determine their relationship to vaccine strains. Samples will be tested by real-time PCR, virus isolation and serological ELISA testing to detect structural and non-structural FMDV protein antibodies. Strains obtained from acute and persistent or subclinical infections will be genetically and antigenically characterized by ARS, PIADC and LANAVET. 4. Provide the basic information necessary to support the progressive control of FMD in the Northern Regions of Cameroon. Data generated from sample analysis will shared with National Authorities in Cameroon in charge of FMD control. Vaccine development efforts utilizing the data generated will be used by LANAVET in vaccine development.
3. Progress Report:
The goal of this project is to understand the ecology of Foot-and-Mouth Disease Virus (FMDV) circulating both clinically and sub-clinically in the cattle population of Cameroon. The objectives include conducting basic epidemiological characterization and determining the antigenicity of strains for future vaccination programs to guide the control of FMD. LANAVET conducted field investigations and performed preliminary testing of samples collected. Three herds were selected with a minimum of fifty animals sampled in each of six veterinary centers. Four hundred and seventy five animals were enrolled in the study and ear tagged. Oropharyngeal fluid, serum and epithelial tissues from un-ruptured or freshly ruptured vesicles were collected every two months. In addition clinical cases were sampled in the Northern regions. To date, animals have been sampled twice. Out of 475 serum samples tested 84% were positive for non-structural FMDV antibodies, suggesting the animals have been exposed to FMDV. Epithelial tissues from clinical cases were tested by antigen detection ELISA and conventional PCR. The antigen detection ELISA has identified serotype O, serotype SAT 2 and possibly serotype SAT 1. Samples will be shipped to ARS, PIADC for further analysis. Additionally sampling techniques and laboratory procedures were taught to technicians and public veterinarians. Due to some of the findings in this project, for the first time in the history of Cameroon, vaccination against FMD will commence in 2013 with trivalent vaccine containing serotypes SAT 2, O and A. This will aid in the progressive control of the disease and thus improve the productivity of the livestock sector. No publications have been produced for this project.