Enteric Coronavirus Infection in a Juvenile Dromedary (Camelus Dromedarius)

Abstract

Abstract.A case of an enteric coronavirus infection in a 6-week-old dromedary calf is described. The animal had diarrhea for 5 days and died despite symptomatic treatment. Numerous viral particles, approximately 140 nm in diameter, with club-like projections were detected in the feces by electron microscopy. These characteristics were consistent with a coronavirus. Immunohistochemical reactivity with 2 antigenic group II coronavirus-specific antibodies confirmed the presence of viral antigen in colonic epithelial cells. The death of the animal was attributed to a neutrophilic and emphysematous colitis that likely was caused by an infection with a Clostridium sp.A 6-week-old female dromedary (Camelus dromedarius) calf with a history of acute diarrhea died 5 days after the initial symptoms. According to the owner, the calf was born in Missouri on a pasture that was also inhabited by zebras. The camel nursed from its mother for 1 week after birth. At 1 week of age, the calf was separated from its mother and shipped to a farm in Wisconsin. Upon arrival, the calf was contained indoors and initially fed approximately 1 liter of warm calf milk replacer a containing oxytetracycline and neomycin 4 times per day. The amount of milk replacer was gradually increased to approximately 2 liters per feeding. Clover grass hay was available at all times. The calf had contact with miniature horses, zebras, and reindeers that were kept in the same barn in different stalls. The calf was healthy for approximately 4 weeks. Its weight was approximately 75 kg. Five days before death, the calf developed watery diarrhea after initially being bloated. The owner administered penicillin (approximately 20,000 units/kg) intramuscularly. The calf was presented to the referring veterinarian for the first time approximately 1 day after the initial signs were noted by the owner. The animal appeared to be mildly dehydrated. The calf was treated by the veterinarian with butorphanol, b dipyrone, c and flunixin meglumine d intravenously and received electrolytes per os because it was still drinking. At the second visit 2 days later, the rectal temperature was approximately 35 C (reference range 7 : 36-40 C). The hematocrit was slightly elevated (37.5%; reference range 13 : 26-31%). The calf was tachycardic (60 heart beats/ minute; reference range 7 : 40-50 beats/minute). The white blood cell count was 16,000 leukocytes/ml (reference range 13 : 13,000-24,000) with neutrophilia (83%; reference range 13 : 53-74%). The anti-inflammatory and antibiotic treatment was continued but the calf died and was submitted to the Department of Veterinary Diagnostic Medicine, University of Minnesota, St. Paul, Minnesota, for postmortem examination. Tissue samples, including small and large intestine, lung, brain, liver, kidney, spleen, heart, intestinal lymph node, and adrenal gland, were fixed in 10% buffered formalin and embedded in paraffin. Sections cut at 4 m were stained with hematoxylin and eosin (HE). Additional sections of the intestine were stained with a mod...

Geographic Distribution of MERS Coronavirus among Dromedary Camels, Africa

“…Array results were confirmed on a selection of positive and negative serum samples (n = 14 per country) in MERS-CoV neutralization tests performed as described ( 2 ) (Table 2). Serum samples from 72%, 82%, and 67% of the dromedaries from Nigeria, Ethiopia, and Tunisia, respectively, reacted with the OC43 antigen, confirming common circulation of ΒCoV in camelids ( 7 , 12 ). All samples tested negative for severe acute respiratory syndrome CoV (data not shown).…”

“…Results were expressed as relative mean fluorescent intensity (RFU) for each set of quadruplicate spots of antigen, with a cutoff of 4,000 RFU as used by Meyer et al ( 6 ). Human CoV OC43 S1 was used as a proxy for bovine coronavirus (ΒCoV), the latter of which is known to circulate commonly in dromedaries ( 7 , 12 ). High percentages of animals seropositive for MERS-CoV were observed in Nigeria and Ethiopia; the overall seropositivity was 94% in adult dromedaries in Nigeria and 93% and 97% for juvenile and adult animals, respectively, in Ethiopia (Table 1).…”

Novel Betacoronavirus in Dromedaries of the Middle East, 2013

“…In this study, 4 of the 12 positive samples were collected from dromedaries with diarrhea. A previous report also described the presence of a betacoronavirus in the fecal sample of a dromedary calf with diarrhea ( 35 ). This finding raises the question of the pathologic significance of DcCoV UAE-HKU23 for camelids and warrants further animal studies.…”

Geographic Distribution of MERS Coronavirus among Dromedary Camels, Africa

“…Array results were confirmed on a selection of positive and negative serum samples (n = 14 per country) in MERS-CoV neutralization tests performed as described (2) ( Table 2). Serum samples from 72%, 82%, and 67% of the dromedaries from Nigeria, Ethiopia, and Tunisia, respectively, reacted with the OC43 antigen, confirming common circulation of BCoV in camelids (7,12). All samples tested negative for severe acute respiratory syndrome CoV (data not shown).…”

“…Results were expressed as relative mean fluorescent intensity (RFU) for each set of quadruplicate spots of antigen, with a cutoff of 4,000 RFU as used by Meyer et al (6). Human CoV OC43 S1 was used as a proxy for bovine coronavirus (BCoV), the latter of which is known to circulate commonly in dromedaries (7,12). High percentages of animals seropositive for MERS-CoV were observed in Nigeria and Ethiopia; the overall seropositivity was 94% in adult dromedaries in Nigeria and 93% and 97% for juvenile and adult animals, respectively, in Ethiopia (Table 1).…”