Abstract
Between September 1970 and May 1971 six cases of human infection with monkeypox virus were identified in three West African countries—Liberia, Sierra Leone, and Nigeria. Four of the cases were confirmed by viral isolation, and two were diagnosed on epidemiological and serological evidence. Poxvirus strains isolated from the four cases were indistinguishable from reference monkeypox strains (Copenhagen and Utrecht), and all were easily differentiated from variola and vaccinia viruses. The isolated strains produced small necrotic haemorrhagic pocks on CAM, grew well at 39.0°C, formed large plaques in Vero cell cultures, showed markedly more virulence for chick embryos and mice than do variola strains, and produced large necrotic haemorrhagic local lesions with generalized illness and florid secondary exanthem when inoculated into rabbit skin.
The finding of smallpox-like illness in humans resulting from infection with a poxvirus of lower animal origin serves to emphasize the importance of thorough epidemiological and laboratory evaluation of all suspect smallpox cases occurring in areas where smallpox has been or is about to be eradicated.
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- BAUER D. J. Some applications of a single-dilution method of titrating neurotropic viruses in zero mortality (Do) units. Br J Exp Pathol. 1960 Apr;41:130–139. [PMC free article] [PubMed] [Google Scholar]
- BEDSON H. S., DUMBELL K. R. The effect of temperature on the growth of pox viruses in the chick embryo. J Hyg (Lond) 1961 Dec;59:457–469. doi: 10.1017/s0022172400039152. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cruickshank J. G., Bedson H. S., Watson D. H. Electron microscopy in the rapid diagnosis of smallpox. Lancet. 1966 Sep 3;2(7462):527–530. doi: 10.1016/s0140-6736(66)92882-0. [DOI] [PubMed] [Google Scholar]
- DUMBELL K. R., NIZAMUDDIN M. An agar-gel precipitation test for the laboratory diagnosis of smallpox. Lancet. 1959 May 2;1(7079):916–917. doi: 10.1016/s0140-6736(59)91315-7. [DOI] [PubMed] [Google Scholar]
- Macfarlane D. E., Sommerville R. G. VERO cells (Cercopithecus aethiops kidney)--growth characteristics and viral susceptibility for use in diagnostic virology. (Brief report). Arch Gesamte Virusforsch. 1969;27(2):379–385. doi: 10.1007/BF01249659. [DOI] [PubMed] [Google Scholar]
- Noble J., Jr A study of New and Old World monkeys to determine the likelihood of a simian reservoir of smallpox. Bull World Health Organ. 1970;42(4):509–514. [PMC free article] [PubMed] [Google Scholar]
- Noble J., Jr, Long G. W., Kirchner E., Sesso J. A clinical and laboratory study of smallpox in Brazil. Accuracy of the laboratory diagnosis of smallpox in patients with Brazilian variola minor infection. Am J Trop Med Hyg. 1970 Nov;19(6):1020–1028. doi: 10.4269/ajtmh.1970.19.1020. [DOI] [PubMed] [Google Scholar]
- Noble J., Jr, Rich J. A. Trsmission of smallpox by contact and by aerosol routes in Macaca irus. Bull World Health Organ. 1969;40(2):279–286. [PMC free article] [PubMed] [Google Scholar]
- PRIER J. E., SAUER R. M., MALSBERGER R. G., SILLAMAN J. M. Studies on a pox disease of monkeys. II. Isolation of the etiologic agent. Am J Vet Res. 1960 May;21:381–384. [PubMed] [Google Scholar]