No abstract

summaryThis study describes aspects of measles in non-human primates. Monkeys infected before importation are shown to produce non-immune offspring in captivity in England. The high antibody titres found in most recently imported monkeys decline slowly during captivity in England. While measles is often fatal to monkeys, we have described an outbreak in which a number of symptomless infections occurred. Histological examination of fatal cases produced evidence of infection in the wall of the urinary bladder in one monkey. The close similarity between measles in humans and monkeys has been confirmed. It is considered that the study of infection among the latter may have significance for the former.

30 rhesus monkeys ( Macaca mulatta), born into a breeding colony, received measles vaccination when aged between 3 and 26 months; 28 of them were re-vaccinated 5 to 7 months later. Measles virus antibody was measured by haemagglutination-inhibition at the time of each vaccination and again 3 to 6 weeks later. Only 2 out of 9 animals aged less than 6 months responded to vaccination, whereas 10 out of 14 older animals showed 4-fold or greater rises. Re-vaccination of the younger group when aged 8 to 10 months resulted in a marked rise in antibody.