Adverse Reactions to Field Vaccination Against Lumpy Skin Disease in Jordan.

Lumpy skin disease (LSD) is an emerging disease in the Middle East region and has been recently reported in Jordan. The aim of this study was to investigate the adverse reactions that were reported after vaccine administration. Geographical areas enrolled in the study were free of the disease and away from the outbreak governorate. Sixty-three dairy cattle farms, with a total of 19,539 animals, were included in the study. Of those, 56 farms reported adverse clinical signs after vaccine administration. The duration between vaccine administration and appearance of adverse clinical signs ranged from 1 to 20 days (Mean = 10.3, SD ± 3.9). Clinical signs were similar to those observed with natural cases of lumpy skin disease. These were mainly fever, decreased feed intake, decreased milk production and variable sized cutaneous nodules (a few millimetres to around 2 cm in diameter) that could be seen anywhere on the body (head, neck, trunk, perineum), udder, and/or teats. Nodules were raised and firm initially and then formed dry scabs that could be peeled off the skin. The characteristic deep 'sit fast' appearance was rarely seen and most lesions were superficial. Some cattle had swollen lymph nodes, while a few pregnant animals aborted. The percentage of affected cattle ranged from 0.3 to 25% (Mean = 8, SD ± 5.1). Fever, decreased feed intake, and decreased milk production were seen in 83.9, 85.7, and 94.6% in cattle on the affected farms, respectively. All affected cattle displayed skin nodules over their entire bodies, while 33.9 and 7.1% of the affected farms reported nodular lesions present on the udders and teats, respectively. No mortalities were reported due to vaccine adverse reactions. Duration (course) of clinical signs ranged from 3 to 20 days (Mean = 13.7, SD ± 4.1). Two types of LSD vaccines were used by the farmers in this study. The first one was a sheep pox virus (SPPV) vaccine derived from the RM65 isolate [Jovivac, manufactured by Jordan Bioindustries Centre (JOVAC)] and the other an unlabelled one, which was later identified using PCR as a strain of lumpy skin disease virus (LSDV). Blood and skin samples collected from cattle vaccinated with the LSDV vaccine were positive for LSDV using both general and species-specific PCR primers, whereas those from cattle vaccinated with the Jovivac vaccine were negative. Adverse reactions observed in cattle after administration of the LSDV vaccine were reported to be more severe than those seen after Jovivac vaccine administration and were comparable with clinical signs observed in natural infections.

Lumpy Skin Disease in Jordan: Disease Emergence, Clinical Signs, Complications and Preliminary-associated Economic Losses.

The objectives of this study are to report the emergence of lumpy skin disease (LSD) in Jordan and associated clinical signs, complications and preliminary economic losses. In mid-April, 2013, two adult dairy cattle developed clinical signs suggestive of LSD and were confirmed as positive by PCR. The two cases were in Bani Kenanah district, Irbid governorate, on the Jordanian border of Israel and Syria. The disease spread rapidly to all the districts of Irbid governorate. During the month following the emergence of the disease, data were collected related to the epidemiology of the disease and the numbers of affected cattle on the premises. Forty-one dairy cattle holdings were surveyed. The morbidity rate ranged from 3% to 100%, (Mean = 35.1%, SD ±28.5%). The mortality rate ranged from 0% to 20%, (Mean = 1.3%, SD ±4.4%). The case fatality rate ranged from 0% to 100%, (Mean = 6.2%, SD ±22%). The overall morbidity rate was 26%, mortality rate 1.9% and case fatality rate 7.5%. Skin nodules, anorexia, decreased milk production and decreased body weight were common clinical signs, while mastitis and myiasis were seen as complications in a few affected animals. Decreased body weight ranged from 0% to 80%, (Mean = 23.1%, SD ±15.7%). Decreased milk production ranged from 0% to 100%, (Mean = 51.5%, SD ±22.2%). Affected cattle were treated mainly with broad-spectrum antibiotics and anti-inflammatory drugs. The cost of treatment ranged from 0 to 84.3 British Pound/animal, (Mean = 27.9 GBP, SD ±22.5 GBP). LSD continues to spread through the Middle East region and poses a serious threat to the rest of Asia and Europe. International collaboration and communication is warranted to prevent the further spread of the disease to the rest of Asia and Europe.