Plague in South Africa: a study of the epizootic cycle in gerbils ( Tatera brantsi ) in the northern Orange Free State

1. The course of an epizootic of plague in thirty-four colonies of gerbils ( Tatera brantsi ) was observed by counting, at 4-weekly intervals, the number of burrows which, when they had been closed on one day, were found open on the next. One gerbil could open an average of eight burrows in one nigh...

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Bibliographic Details
Published in:Epidemiology and Infection
Main Author: Davis, D. H. S.
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 1953
Subjects:
Online Access:http://dx.doi.org/10.1017/s0022172400036718
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022172400036718
Description
Summary:1. The course of an epizootic of plague in thirty-four colonies of gerbils ( Tatera brantsi ) was observed by counting, at 4-weekly intervals, the number of burrows which, when they had been closed on one day, were found open on the next. One gerbil could open an average of eight burrows in one night. 2. Regular censuses on the twenty-one colonies which survived until the last phase of the epizootic showed that the gerbil population fell from about 420 at the end of June 1940 to none at the end of January 1941. From May 1941 to August 1942, 3-monthly counts revealed some recolonization, but field officers reported that between 1942 and 1951 the gerbils sometimes died from plague, and the population never regained its former level. 3. During 1940, two to four colonies died out every 4 weeks. The time of year seemed not to influence the course of the epizootic. 4. Pasteurella pestis was detected in some gerbil colonies 4–6 months before they died out. 5. Plague-infected gerbil fleas were found which had been immured in blocked deserted burrows for periods of up to 120 days. 6. The passage of infection was traced from the reservoir in gerbils to other wild rodents ( Otomys irroratus, Rattus ( Mastomys ) natalensis ), to house rats ( Rattus rattus ) and to man.