University of Khartoum

The Epidemiology of Foot-and-Mouth Disease in the Sudan

The Epidemiology of Foot-and-Mouth Disease in the Sudan

Show full item record

Title: The Epidemiology of Foot-and-Mouth Disease in the Sudan
Author: Habeeb Allah, Hanan Yousif Mohamed Ahmed
Abstract: Retrospective and prospective studies were conducted to understand the epidemiology of FMD in the country in order to support and refine the current control programme. Material and methods used were mainly retrospective data collection from passive reporting, sera samples from apparently healthy animal, and epithelia tissues from clinically affected species in the field and semi structured questionnaire was used to understand the economic impact and the main risk factors contributing to the spread of the disease. Tests used were 3-ABC antibodies using the Prio-check ELISA. Positive sera were further tested for type “O”, “A” and “SAT2” antibodies using SNT. The study demonstrated that FMD is endemic and periodically epidemic in the country with the states and localities bordering Egypt, Ethiopia, Eretria, Republic of South Sudan and Libya being at higher risk of disease than the interior states. The states and localities bordering Egypt, Ethiopia, and Eretria appear to behave like primary endemic areas for the introduction and persistence of FMD virus through frequent unofficial movements of cattle across the porous border. The interior states and localities appear to behave like secondary endemic areas where virus propagation occurs due to limited vaccination coverage and unrestricted movement of animals. Serotype O was indicated as the principal serotype in the country, consistent with the disease epidemiology in the neighboring countries. Cattle are the most susceptible animal while small ruminants and pigs seem to have minor roles in the disease’s epidemiology. Outbreaks of FMD, in cyclical patterns, have occurred in the country. The disease produced 20.5% morbidities and 2% mortalities from retrospective data collected from January 2003 – December 2013. The overall sero-prevalence within different serotypes against the geographical areas was indicated as follows: O was 59.3%, A was 24.2%, vi and SAT2 was 12%. Phylogenetic analysis of epithelia samples from FMD clinically affected cattle for the years 2009, 2010 and 2011 was conducted, Serotype O was the most predominant and belongs to topotype EA-3, most of the isolates showed 99% identity with the Sudanese Archive virus, one single isolate Sud/9/2011 showed 95% identity with Eritrean and Ethiopian isolates. Serotypes A isolate belongs to topotype AFRICA, the Phylogenetic analysis showed large similarity with Egyptian isolates by 97.97%, SAT2 isolate belongs to topotype VII, the phylogenetic analysis showed large similarity with isolates in North and West Africa and with Egyptian isolates for 2012 by 95.83% identity, 92.58% with Saudi Arabia. Husbandry practices, such as mix farming, sharing animal grazing and watering areas, and feeding cattle with ready prepared concentrate from market, bio-security seem to be significantly increasing the risk of transmission of FMD among herds. The overall sero-prevalence for serotypes with in production system was 59.2% for O, 30.1% for A and 12% for SAT2. This indicated that the production systems are highly influencing the spread of the disease and more animal are affected in resident production system which is mostly dairy farming. The overall sero-prevalence within sex showed that, serotype O was most prevalent among females 61.7%, followed by A, 32.3% and SAT2, 12.6%. Sero-prevalence within age showed that, the most affected age group was <= 1year, and serotype O was most prevalent 59.3%, A was 30.2% and SAT2 was 12%. An estimate was made on the impact of FMD in 2014 in the country. The total impact of the disease was calculated to be SDG 3.0 milliards (US$ 482 thousands) annually in eleven states of the country during the study period. The impact of the disease per head of cattle was SDG 8.2 (US$ 1.26) and SDG 2.56 per person (US$ 0.4). 99% of impact recorded in 11 states of the country was due to direct losses (milk, abortion and deaths among young animal), whereas, 1% of the impact in the same study area due to cost of control, mostly treatment for secondary infections. The US$ vii 482 thousands is likely to be a very conservative estimate of the national (eleven states in the study area) FMD annual impacts. In conclusion, active serological and questionnaire-based surveys have validated the usefulness of the country’s passive surveillance system. Although the current findings have increased the level of confidence in the passive surveillance system of the country, there is a need to complement this with active serological and clinical surveys periodically. Several factors, such as extensive livestock husbandry practices, age, sex, inadequate vaccination coverage, ineffective regulation of movement control, porous borders, a lack of awareness on vaccination against the disease by the farming community, and budgetary constraints, pose significant challenges to the prevention and control of FMD in the country. Direct losses of the disease due to death, milk reduction and abortion are easy to appreciate, however, in the country the burden of FMD often manifests as widespread and ongoing losses that may limit development opportunities for developing the livestock sector, specially the dairy sector.
URI: http://khartoumspace.uofk.edu/123456789/26105


Files in this item

Files Size Format View

This item appears in the following Collection(s)

Show full item record

Share

Search DSpace


Browse

My Account