Seroprevalence and Molecular Detection of Foot and Mouth Disease Virus in Dairy Cattle Around Addis Ababa, Central Ethiopia

Abstract

Background: Foot and mouth disease is a debilitating and highly contagious transboundary disease of cattle that can cause a huge economical loss globally. It is a notifiable disease in Ethiopia, and it is thought to be causing a decrease in cattle productivity and production. Methods: A cross-sectional study and outbreak investigation were performed to estimate seroprevalence, identify associated factors and serotypes of FMDV in dairy cattle around Addis Ababa. A multi-stage random sampling technique was employed for the selection of sampling units for the seroprevalence study. A total of 383 blood samples were collected using plain vacutainer tubes and the obtained sera were tested by 3ABC-Ab ELISA at the NAHDIC lab. Also, from outbreak cases, 20 epithelial tissue samples were collected purposively for the molecular detection of FMDV serotypes. Results: The overall seroprevalence of FMD in dairy cattle was 72.1% (95% CI=67.27-76.50). The seroprevalence in dairy cattle of Ada Berga, Holeta, and Sululta districts was 97.2%, 71.4%, and 57.6%, respectively. Up on Chi-square analysis, age, body condition, and management system were significantly associated with FMD seroprevalence (p<0.05). Besides, multivariable logistic regression analysis showed that district, age, body condition, and management were significantly associated with FMD seroprevalence (p<0.05). The odds of being seropositive to FMD were 6.9 (95% CI=1.8-24.9; p=0.005) and 2.3 (95% CI=1.2-4.7; p=0.01) times higher in cattle found in Ada Berga and Holeta Woreda. From outbreak cases, 18 (90.0%) were identified positive for FMDV serotype O. Conclusion:The current study revealed higher seroprevalence was recorded in the study area and associated risk factors identified statically, serotype O of FMDV was identified from outbreak cases. Therefore, it is critical to design and implement feasible control and prevention mechanisms based on the type of circulating virus serotype.

Risk Factor Assessment, Sero-Prevalence, and Genotyping of the Virus That Causes Foot-and-Mouth Disease on Commercial Farms in Ethiopia from October 2018 to February 2020

“…The observed high prevalence in the current study could be attributed to the geographical location of the farms, failure to periodically vaccinate animals, improper management practices, herding of farm animals near to wildlife areas, and contact of animals with livestock of other neighborhoods. On the contrary, seroprevalence documented in this survey showed a much higher value as compared to the previous reports of 10.5% of national prevalence, 9.5% from southern Ethiopia, 8.18% from South Omo, Ethiopia, and 14.05% from Eastern Hararge, Ethiopia by [9,11,49,50], respectively On the other hand, a much higher prevalence than the present study was reported, i.e., 42.7% in Borena, southern Ethiopia by [51], 72.1% in central Ethiopia [18], and 52.5% in Kenya by [52] in cattle. These differences could be related to variation in agroecology, geo-spatial distribution of the disease, possible sampling after an outbreak, and variations in the production/herding systems among the areas of the study.…”

“…Statistical inference was difficult, as the sample sizes between groups differ and are small. The chance of being sero-positive was higher in adult animals (>18 months) with OR: 6, 95 % CI, [2,18] as compared to their younger counterparts. Caprine species were seen to have 3.8% sero-positivity, but the chance was eight times higher (OR: 8, 95% CI, [3,22]) for ovine as compared to caprine.…”

“…Furthermore, a seroprevalence of 30% was reported in ungulate wild mammals [16]. A recent report from dairy farms of central Ethiopia indicated a seroprevalence of 72.1% [18]. In Ethiopia, outbreak investigation studies indicated that FMD occurs year-round in most parts of the country.…”

Deciphering Molecular Dynamics of Foot and Mouth Disease Virus (FMDV): A Looming Threat to Pakistan’s Dairy Industry

“…These serotypes are reported frequently from one part or another part of the world. The low infectious dose of the virus, rapid replication, prolonged environmental survival, the incubation period of 7-14 days, and high virus titer in nasal secretions contributes to the rapid transmission of the virus to the susceptible animal population [7]. The disease-causing ability of FMDV is different for different animals, which may depend on different factors such as the duration of virus present in the body, abrasion through which virus enters the body, and release of virus titer [8].…”

“…Besides animal-animal transmission via respiratory aerosols, the virus is disseminated easily via mechanical routes, i.e., fomites, shoes, clothes, vehicles, and veterinary surgical instruments. Furthermore, the uncontrolled transboundary movements of animals have also aggravated its spread [7].…”