West Nile virus (WNV) is a global important mosquito-borne Flavivirus causing West Nile disease (WND). In Libya, evidence of WNV circulation has been reported in humans but never in animals. The aim of this study was to determine the seroprevalence of the WNV infection in horses and dogs in Libya. A total of 574 and 63 serum samples from horses and dogs, respectively, were collected from healthy unvaccinated animals between 2016 - 2019. A commercially available competitive ELISA (c-ELISA) kit was initially used to test the collected samples for the presence of WNV Ig-G antibodies. Positive and doubtful sera were also tested by using the more specific virus neutralization assays to confirm whether the ELISA positive results were due to WNV or Usutu virus (USUV) antibodies. The seroprevalence of WNV IgG ELISA antibodies was 13.2% (76/574) and 30.2% (19/63) in horses and dogs, respectively. Virus neutralization test (VNT) showed that 77.5% (62/80) and 89.5% (17/19) of positive and doubtful horse serum samples and dogs serum samples, respectively, were positive with WNV neutralising titers ranging from 1:10 to 1:640. The results of the present study provided novel evidence about the WNV circulation in Libya.

Lumpy skin disease (LSD) is a viral disease of cattle and water buffalo characterized by cutaneous nodules, biphasic fever and lymphadenitis. LSD is endemic in Africa and Middle East but in recent years has spread in different Asian countries. Drop of animal productions, vaccination campaign, surveillance costs and trade restrictions have significant impact on the economy of affected countries. The disease is well characterized in cattle while little is known in buffaloes and no experimental studies have been conducted in this species. Six buffaloes and two cattle were inoculated with an Albanian LSD virus (LSDV) field strain. Over a period of 42 days animals were clinically monitored and sampled for serological and virological analysis. Only two buffaloes showed clinical sign, fever, skin nodules and lymphadenitis. All samples tested in real time PCR (blood, swabs, biopsies and organ) gave negative results. Three buffaloes seroconverted at day 39 and 42 post-inoculation, detected by ELISA, but all sera were negative in serum neutralization test. Cattle showed more severe clinical signs. Moreover, viraemia and virus shedding were proven by positive PCR results and antibodies were detected by both ELISA and serum neutralization test. These findings demonstrated the limited susceptibility of buffaloes compared to cattle once experimental infected with LSDV. Further studies are needed to investigate the epidemiological role of the buffaloes.