Samad LotfollahzadehUniversity of Tehran, Iran
Title: Evaluation of efficacy and safety of a homologous Lumpy Skin Disease vaccine against circulating lumpy skin disease virus in Iran
Lumpy skin disease is a viral disease in cattle and Asian water buffalo, causing nodules in susceptible animal's skin. Implementation of mass vaccination in susceptible animals in the appropriate period of year is the most effective way for LSD control. LSD vaccine that was used in the current study is a vaccine that is produced domestically which contains live attenuated Neethling strain of LSD virus. In the current study, the safety and efficacy of this vaccine in susceptible animals in controlled field condition were evaluated. In this clinical trial, 15 purebred and crossbreed Holstein male cattle, aged 6 to 9 months, approximately 150 to 250 kg weight, and without antibodies against LSDV were selected. The cattle were divided into three groups: The first group consisted of two animals that were injected subcutaneously with ten times the vaccine dose in the mid-cervical area, the second group was comprised of eight cattle that were inoculated subcutaneously with 1 dose of vaccine in the mid-cervical area and the third group consisted of five cattle that received the vaccine diluent and were assigned as control group. On the 21st day, after injection, the experimental animals in three groups were challenged intravenously and intradermally with one pathogen LSD virus that was circulating in Iran. All 15 cattle were examined clinically daily for 21 days after the vaccination to evaluate the safety of vaccine and subsequently 14 days later for efficacy test. None of the vaccinated animals (10 times the dose of vaccine, single dose of vaccine and diluent) showed any abnormal clinical signs within the first 21 days of experiment. Subsequently, during efficacy test and after animals were challenge, all the animals in the control group showed clinical signs of LSD including cutaneous nodules while animals in vaccinated group did not show any clinical signs of disease. Also, four out of the five cattle in the control group showed increased rectal temperature with varying degrees on various days after the challenge.