Humoral Immunogenicity and Efficacy of a Single Dose of ChAdOx1 MERS Vaccine Candidate in Dromedary Camels

Sci Rep. 2019 Nov 8;9(1):16292. doi: 10.1038/s41598-019-52730-4.


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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenoviridae / immunology
  • Animals
  • Antibodies, Neutralizing / immunology
  • Antibodies, Viral / immunology
  • Camelus / immunology*
  • Camelus / metabolism
  • Coronavirus Infections / prevention & control
  • Coronavirus Infections / veterinary
  • Coronavirus Infections / virology
  • Disease Outbreaks
  • Middle East Respiratory Syndrome Coronavirus / immunology*
  • Middle East Respiratory Syndrome Coronavirus / metabolism
  • Middle East Respiratory Syndrome Coronavirus / pathogenicity
  • Middle East Respiratory Syndrome Coronavirus / physiology
  • Vaccination / methods
  • Viral Vaccines / immunology
  • Viral Vaccines / pharmacology*
  • Zoonoses / epidemiology


  • Antibodies, Neutralizing
  • Antibodies, Viral
  • COVID-19 vaccine
  • Viral Vaccines