Epidemiology of camel contagious ecthyma and molecular detection of the pathogen in Arero district, Ethiopia

Abstract

Even though camels (Camelus dromedarius) were traditionally believed to be resistant to most livestock diseases, research has demonstrated that they are susceptible to a large number of infectious agents. Based on the clinical appearance of typical lesions, camel contagious ecthyma (CCE), caused by a Parapoxvirus (PPV), is thought to be one of the most common viral diseases of camels in Ethiopia. A cross-sectional study was conducted from November 2013 to April 2014 in the Arero district of Borena Zone, Oromia Regional State of Ethiopia to investigate the epidemiological aspect of CCE and molecularly identify the causative agent. A polymerase chain reaction (PCR) based on B2L gene-specific primers of PPV was used for the confirmatory diagnosis of the CCE virus from the skin lesion of camels showing suspected clinical signs of CCE infection. Eighty-seven percent (87.0%) of camel owners reported the occurrence of CCE outbreaks in their herds in the past year (a year preceding the start of the study). The overall morbidity and mortality rates attributed to CCE were 20% (95% CI: 11– 36%) and 6.3% (95 % CI: 5.2 –7.6%), respectively. Younger camels had higher odds of becoming affected by CCE than adults [OR=3.44 (95 % CI: 2.29 –4.09)] and the difference was statistically significant. Confirmatory diagnosis of the suspected cases using conventional PCR generated the expected amplification product size of 1200bp for one of the samples. Therefore, the study confirms the presence and importance of CCE in Ethiopia and establishes the basis for further investigation.