MERS-CoV seronegative and seropositive camels received a single intramuscular dose of ChAdOx1 MERS, a replication-deficient adenoviral vectored vaccine expressing MERS-CoV spike protein, with further groups receiving control vaccinations. Infectious camels with active naturally acquired MERS-CoV infection, were co-housed with the vaccinated camels at a ratio of 1:2 (infected:vaccinated); nasal discharge and virus titres were monitored for 14 days. Overall, the vaccination reduced virus shedding and nasal discharge (p = 0.0059 and p = 0.0274, respectively). Antibody responses in seropositive camels were enhancedby the vaccine; these camels had a higher average age than seronegative. Older seronegative camels responded more strongly to vaccination than younger animals; and neutralising antibodies were detected in nasal swabs. Further work is required to optimise vaccine regimens for younger seronegative camels.

Lumpy skin disease (LSD) is a highly infectious disease of cattle caused by a virus of the Capripoxvirus genus in the family Poxviridae. The disease is a major concern for the dairy industry in Saudi Arabia. In this study, an outbreak of LSD in cattle herds was detected in Saudi Arabia in 2016. LSD outbreak was investigated in five regions of Saudi Arabia: Al-Hassa, Al-Sharqia, Al-Qassim, Riyadh and Al-Taif during the period from April to July 2016. Tissues from skin nodules were collected to characterize the virus by a real-time polymerase chain reaction (rt-PCR). During this period, 64,109 cattle were examined and morbidity, mortality and case fatality rates were 6%, 0.99% and 16.6%, respectively. The analysis showed 3,852 infected cases and 641 deaths. highest number of infected animals was reported in Al-Hassa (2,825), followed by Al-Qassim (547), Riyadh (471), Al-Sharqia (6) and Al-Taif (3). The highest morbidity rates were observed in Al-Qassim (6.8%), Al-Hassa (6.2%), Riyadh (5.5%) and Al-Taif (0.96%), while the lowest morbidity rates were recorded in Al-Sharqia (0.27%). The highest mortality rates were also observed in Al-Qassim (2.3%), followed by Al-Hassa (0.97%), Riyadh (0.19%) and lowest in Al-Sharqia and Taif (0%). LSD virus was detected in all samples (n = 191) by real-time PCR analysis. The disease has been observed in the cattle regardless of previous vaccination using the locally Romanian-pox vaccine; therefore, vaccination programme and vaccine efficacy should be assessed under field conditions.

Some pathological observations on the naturally infected dromedary camels (Camelus dromedarius) with the Middle East respiratory syndrome coronavirus (MERS-CoV) in

These findings indicate that these sites are a highly-hazardous to zoonotic diseases.

Background: Middle East Respiratory Syndrome coronavirus (MERS-CoV) is an emerging virus that infects humans and camels with no approved antiviral therapy or vaccine. Some vaccines are in development for camels as a one-health intervention where vaccinating camels is proposed to reduce human viral exposure. This intervention will require an understanding of the prior exposure of camels to the virus and appropriate vaccine efficacy studies in camels. Methods: We conducted a cross sectional seroprevalence study in young dromedary camels to determine the rate of MERS-CoV seropositivity in young camels. Next, we utilised naturally infected camels as a natural challenge model that can be used by co-housing these camels with healthy naive camels in a ratio of 1 to 2. This model is aimed to support studies on natural virus transmission as well as evaluating drug and vaccine efficacy. Results: We found that 90% of the screened camels have pre-existing antibodies for MERS-CoV. In addition, the challenge model resulted in MERS-CoV transmission within 48 h with infections that continued for 14 days post challenge. Conclusions: Our finding suggests that the majority of young dromedary camels in Saudi Arabia are seropositive and that naturally infected camels can serve as a challenge model to assess transmission, therapeutics, and vaccine efficacy.