[Source: US Centers for Disease Control and Prevention (CDC), Emerging Infectious Diseases Journal, full page: (LINK). Abstract, edited.]
Volume 23, Number 8—August 2017 / Research
Molecular Characterization of Corynebacterium diphtheriae Outbreak Isolates, South Africa, March–June 2015
Mignon du Plessis, Nicole Wolter, Mushal Allam, Linda de Gouveia, Fahima Moosa, Genevie Ntshoe, Lucille Blumberg, Cheryl Cohen, Marshagne Smith, Portia Mutevedzi, Juno Thomas, Valentino Horne, Prashini Moodley, Moherndran Archary, Yesholata Mahabeer, Saajida Mahomed, Warren Kuhn, Koleka Mlisana, Kerrigan McCarthy, and Anne von Gottberg
Author affiliations: National Health Laboratory Service, Johannesburg, South Africa (M. du Plessis, N. Wolter, M. Allam, L. de Gouveia, F. Moosa, G. Ntshoe, L. Blumberg, C. Cohen, M. Smith, P. Mutevedzi, J. Thomas, K. McCarthy, A. von Gottberg); University of the Witwatersrand, Johannesburg (M. du Plessis, N. Wolter, C. Cohen, A. von Gottberg); National Health Laboratory Service, Cape Town, South Africa (V. Horne); University of KwaZulu-Natal, Durban, South Africa (P. Moodley, M. Archary, Y. Mahabeer, S. Mahomed, W. Kuhn, K. Mlisana); National Health Laboratory Service, Durban (Y. Mahabeer, K. Mlisana); National Department of Health, KwaZulu-Natal, South Africa (W. Kuhn)
In 2015, a cluster of respiratory diphtheria cases was reported from KwaZulu-Natal Province in South Africa. By using whole-genome analysis, we characterized 21 Corynebacterium diphtheriae isolates collected from 20 patients and contacts during the outbreak (1 patient was infected with 2 variants of C. diphtheriae). In addition, we included 1 cutaneous isolate, 2 endocarditis isolates, and 2 archived clinical isolates (ca. 1980) for comparison. Two novel lineages were identified, namely, toxigenic sequence type (ST) ST-378 (n = 17) and nontoxigenic ST-395 (n = 3). One archived isolate and the cutaneous isolate were ST-395, suggesting ongoing circulation of this lineage for >30 years. The absence of preexisting molecular sequence data limits drawing conclusions pertaining to the origin of these strains; however, these findings provide baseline genotypic data for future cases and outbreaks. Neither ST has been reported in any other country; this ST appears to be endemic only in South Africa.
Keywords: Diphtheria; Corynebacterium Diphtheriae; South Africa.