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Trachoma vaccine field trials in The Gambia

Published online by Cambridge University Press:  15 May 2009

Shiona Sowa
Affiliation:
M.R.C. Trachoma Unit, Lister Institute of Preventive Medicine, London, S. W. 1, and Medical Research Council Laboratories, Fajara, The Gambia
J. Sowa
Affiliation:
M.R.C. Trachoma Unit, Lister Institute of Preventive Medicine, London, S. W. 1, and Medical Research Council Laboratories, Fajara, The Gambia
L. H. Collier
Affiliation:
M.R.C. Trachoma Unit, Lister Institute of Preventive Medicine, London, S. W. 1, and Medical Research Council Laboratories, Fajara, The Gambia
W. A. Blyth
Affiliation:
M.R.C. Trachoma Unit, Lister Institute of Preventive Medicine, London, S. W. 1, and Medical Research Council Laboratories, Fajara, The Gambia
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The ability of two live trachoma vaccines to protect against naturally acquired infection was tested in young Gambian children. With a mineral oil adjuvant vaccine prepared from a Gambian strain of trachoma (MRC–187) a barely significant measure of protection was demonstrable 6 months after the first dose, but not at 1 year, despite a reinforcing dose given 6 months after the first. In a later trial an aqueous vaccine prepared from the ‘fast-killing’ variants of strains ‘SA–2’ and ‘ASGH’ failed to induce immunity. Two years after vaccination, the proportion of vaccinated children progressing to cicatricial trachoma was less than in the controls, and the average severity of the disease in terms of clinical score was greater; vaccine-induced hypersensitivity may have contributed to this result.

Irrespective of whether they had received trachoma vaccine, children with completely normal eyes at the outset were less likely to acquire trachoma than those with slight conjunctival folliculosis or papillary hyperplasia. In children acquiring trachoma, there was a highly significant positive correlation between severity of the disease and the presence of conjunctival inclusions. The pattern of trachoma differed significantly in the two villages used in both trials; the prev alence, severity and proportion of inclusion-positive subjects were all higher in the village with the greater population density.

An efficient follow-up organization, use of a slit-lamp for clinical observations, and a scoring system for recording physical signs are all desirable for trachoma vaccine field trials.

We are highly indebted to Dr G. Turner (Lister Institute, Elstree, Herts) for his assistance in making the vaccine used for Trial II; to Dr N. M. Lam (Pfizer Ltd.) and Dr C. H. Smith (Evans Medical Ltd.) for making the Trial III vaccine; to Dr I. A. Sutherland (M.R.C. Statistical Unit) for his advice and help with the statistical aspects; to the Pennsylvania Refinery Co. Inc. for a generous gift of Drakeol 6 VR; and to Mr M. Race for his invaluable technical assistance in The Gambia. We are also grateful to the Director and staff of the M.R.C. Laboratories, The Gambia, for various facilities; and to The Gambian Government for per mission to undertake these trials.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1969

References

REFERENCES

Bell, S. D. & Theobald, B. (1962). Differentiation of trachoma strains on the basis of inmnmization against toxic death of mice. Ann. N.Y. Acad. Sci. 98, 337.CrossRefGoogle ScholarPubMed
Berlin, B. S. (1962). Tests for biologic safety of Arlacel A. Ann. Allergy 20, 472.Google ScholarPubMed
Bovanick, M. R., Miller, J. C. & Snyder, J. C. (1950). The influence of certain salts, amino acids, sugars and proteins on the stability of rickettsiae. J. Bact. 59, 509.CrossRefGoogle Scholar
Collier, L. H. (1961). Experiments with trachoma vaccines: experimental system using inclusion blennorrhoea virus. Lancet i, 795.CrossRefGoogle Scholar
Collier, L. H. (1966). The present status of trachoma vaccination studies. Bull. Wid Hlth Org. 34, 233.Google ScholarPubMed
Collier, L. H. & Blytr, W. A. (1966 a). Immunogenicity of experimental trachoma vaccines in baboons. I. Experimental methods, and preliminary tests with vaccines prepared in chick embryos and in HeLa cells. J. Hyg., Camb. 64, 513.Google ScholarPubMed
Collier, L. H. & Blyth, W. A. (1966 b). Immunogenicity of experimental trachoma vaccines in baboons. II. Experiments with adjuvants, and tests of cross-protection. J. Hyg., Camb. 64, 529.Google ScholarPubMed
Collier, L. H., Blytti, W. A., Labin, N. M. & Treharne, J. (1967). Immunogenicity of experimental trachoma vaccines in baboons. III. Experiments with inactivated vaccines. J. Hyg., Camb. 65, 97.CrossRefGoogle ScholarPubMed
Collier, L. H. & MoGG, A. (1969). Dissemination and immunogenicity of live TRIC agents in baboons after parenteral injection. II. Experiments with a ‘slow-killing’ strain. J. Hyg., Camb. 67, 449.CrossRefGoogle ScholarPubMed
Collier, L. H. & Smith, A. (1967). Dissemination and immunogenicity of live TRIO agents in baboons after parenteral injection. Am. J. Ophthal. 63, 1589.CrossRefGoogle Scholar
Collier, L. H., Sowa, S., Sowa, J. & Blyth, W. (1963). Experiments with trachoma vaccines: therapeutic effect on established trachoma. Orient. Archs Ophthal. 1, 67.Google Scholar
Conference On Trachoma And Allied Diseases, Sab Francisco. (1967). Am. J. Ophthal. 63, No. 5 part II.Google Scholar
Dulbecco, R. & VOGT, M. (1954). Plaque formation and isolation of pure lines with polio myolitis viruses. J. exp. Med. 99, 167.CrossRefGoogle ScholarPubMed
Fisher, R. A. (1958). In Statistical Methods for Research Workers, 13th ed., p. 96. Edited by Crew, R. A. E.. Edinburgh: Oliver and Boyd Ltd.Google Scholar
Fullton, F. & Dumbell, K. R. (1949). The serological comparison of strains of influenza virus. J. yen. Microbiol. 3, 97.Google Scholar
Ftmxxss, G., Graham, D. M. & Reeve, P. (1960). The titration of trachoma and inclusion blennorrhoea viruses in cell cultures. J. yen. Microbiol. 23, 613.Google Scholar
Graham, D. M. (1967). Growth and immunogenicity of TRIC agents in mice. Am. J. Ophthal. 63, 1173.CrossRefGoogle ScholarPubMed
Gtjerra, P., Buogo, A., Mabubini, E. & Grnoirs, M. (1967). Analysis of clinical and labora tory data of an experiment with trachoma vaccine in Ethiopia. Am. J. Ophthal. 63, 1631.Google Scholar
Hanna, L., Jawetz, E., Thygeson, P. & Dawson, C. (1960). Trachoma viruses isolated in United States. I. Growth in embryonated eggs. Proc. Soc. exp. Biol. Med. 104, 142.CrossRefGoogle ScholarPubMed
Mordhorst, C. H. (1967). Experimental infections and immunogenicity of TRIO agents in monkeys. Am. J. Ophthal. 63, 1603.CrossRefGoogle Scholar
Murray, E. S., Bell, S. D. Jr, Hanna, A. T., Nichols, R. L. & Snyder, J. C. (1960). Studies on trachoma. 1. Isolation and identification of strains of elementary bodies from Saudi Arabia and Egypt. Am. J. trop. Med. Hyg. 9, 116.CrossRefGoogle ScholarPubMed
Nichols, R. L., Bobb, A. A., Haddad, N. A. & Mccomb, D. E. (1967). Immunofluorescent studies of the microbiologic epidemiology of trachoma in Saudi Arabia. Am. J. Ophthal. 63, 1372.CrossRefGoogle ScholarPubMed
Reeve, P. & Taverne, J. (1962). A simple method for total particle counts of trachoma and inclusion blennorrhoea viruses. Nature, Lond. 195, 923.CrossRefGoogle ScholarPubMed
Reeve, P. & Taverne, J. (1963). Observations on the growth of trachoma and inclusion blennorrhoea virus in embryonate eggs. J. Hyg., Camb. 61, 67.CrossRefGoogle Scholar
Reeve, P. & Taverns, J. (1967). An assessment of the evidence for regarding the Tang strain as an authentic TRIO agent. Am. J. Ophthal. 63, 1437.CrossRefGoogle Scholar
Snyder, J. C., Nichols, R. L., Bell, S. D. Jr, Itaddad, N. A., Murray, E. S. & Mccomb, D. E. (1964). Vaccination against trachoma in Saudi Arabia: design of field trials and initial results. Indian trop. Hlth 5, 65.Google Scholar
Sowa, S., Sowa, J., Collier, L. H. & Blyth, W. (1965). Trachoma and allied infections in a Gambian village. Spec. Rep. Ser. med. Res. Coun. no. 308.Google Scholar
Tarizzo, M. L., Nabli, B. & Labonne, J. (1968). Studies on trachoma. II. Evaluation of laboratory diagnostic methods under field conditions. Bull. Wid Hith Org. 38, 897.Google Scholar
Wang, S. P., Grayston, J. T. & Alexander, E. R. (1967). Trachoma vaccine studies in monkeys. Am. J. Ophthal. 63, 1615.CrossRefGoogle ScholarPubMed
Woolridge, R. L., Grayston, J. T., Chang, I. H., Cheng, K. H., Yang, C. Y. & Neave, C. (1967). Field trial of a monovalent and of a bivalent mineral oil adjuvant trachoma vaccine in Taiwan school children. Am. J. Ophthal. 63, 1645.CrossRefGoogle ScholarPubMed
World Health Organization (1962). Expert Committee on Trachoma: Third Report. Tech. Rep. Ser. Wld Hlth Org. no. 234.Google Scholar
World Health Organization (1966). Fourth Scientific Group on Trachoma Research. Tech. Rep. Ser. Wid Hlth Org. no. 330.Google Scholar