Lauren M Weil1, Margaret M Williams2, Tahmina Shirin3, Marlon Lawrence4, Zakir H Habib3, Janessa S Aneke5, Maria L Tondella2, Quazi Zaki3, Pamela K Cassiday2, David Lonsway6, Mirza Farrque7, Tanvir Hossen7, Leora R Feldstein1, Nicholas Cook5, Gladys Maldonado-Quiles5, Ahmed N Alam3, A K M Muraduzzaman3, Arifa Akram3, Laura Conklin8, Stephanie Doan9, Michael Friedman9, Anna M Acosta2, Susan Hariri2, LeAnne M Fox2, Tejpratap S P Tiwari2, Meerjady S Flora3. 1. Epidemic Intelligence Service, Division of Scientific Education and Professional Development, Center for Surveillance, Epidemiology, and Laboratory Services, Centers for Disease Control and Prevention, Atlanta, Georgia, USA. 2. Division of Bacterial Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA. 3. Institute of Epidemiology, Disease Control and Research, Dhaka, Bangladesh. 4. Laboratory Leadership Service, Division of Scientific Education and Professional Development, Center for Surveillance, Epidemiology, and Laboratory Services, Centers for Disease Control and Prevention, Atlanta, Georgia, USA. 5. IHRC Inc, Contractor to US Centers for Disease Control and Prevention, Division of Bacterial Diseases, Atlanta, Georgia, USA. 6. Division of Healthcare Quality Promotion, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, USA. 7. Bangladesh Field Epidemiology Training Program, Institute of Epidemiology, Disease Control and Research, Dhaka, Bangladesh. 8. Global Immunization Division, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA. 9. Division of Global Health Protection, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
Abstract
BACKGROUND: Diphtheria, a life-threatening respiratory disease, is caused mainly by toxin-producing strains of Corynebacterium diphtheriae, while nontoxigenic corynebacteria (eg, Corynebacterium pseudodiphtheriticum) rarely causes diphtheria-like illness. Recently, global diphtheria outbreaks have resulted from breakdown of health care infrastructures, particularly in countries experiencing political conflict. This report summarizes a laboratory and epidemiological investigation of a diphtheria outbreak among forcibly displaced Myanmar nationals in Bangladesh. METHODS: Specimens and clinical information were collected from patients presenting at diphtheria treatment centers. Swabs were tested for toxin gene (tox)-bearing C. diphtheriae by real-time polymerase chain reaction (RT-PCR) and culture. The isolation of another Corynebacterium species prompted further laboratory investigation. RESULTS: Among 382 patients, 153 (40%) tested tox positive for C. diphtheriae by RT-PCR; 31 (20%) PCR-positive swabs were culture confirmed. RT-PCR revealed 78% (298/382) of patients tested positive for C. pseudodiphtheriticum. Of patients positive for only C. diphtheriae, 63% (17/27) had severe disease compared to 55% (69/126) positive for both Corynebacterium species, and 38% (66/172) for only C. pseudodiphtheriticum. CONCLUSIONS: We report confirmation of a diphtheria outbreak and identification of a cocirculating Corynebacterium species. The high proportion of C. pseudodiphtheriticum codetection may explain why many suspected patients testing negative for C. diphtheriae presented with diphtheria-like symptoms. Published by Oxford University Press for the Infectious Diseases Society of America 2020.
BACKGROUND: Diphtheria, a life-threatening respiratory disease, is caused mainly by toxin-producing strains of Corynebacterium diphtheriae, while nontoxigenic corynebacteria (eg, Corynebacterium pseudodiphtheriticum) rarely causes diphtheria-like illness. Recently, global diphtheria outbreaks have resulted from breakdown of health care infrastructures, particularly in countries experiencing political conflict. This report summarizes a laboratory and epidemiological investigation of a diphtheria outbreak among forcibly displaced Myanmar nationals in Bangladesh. METHODS: Specimens and clinical information were collected from patients presenting at diphtheria treatment centers. Swabs were tested for toxin gene (tox)-bearing C. diphtheriae by real-time polymerase chain reaction (RT-PCR) and culture. The isolation of another Corynebacterium species prompted further laboratory investigation. RESULTS: Among 382 patients, 153 (40%) tested tox positive for C. diphtheriae by RT-PCR; 31 (20%) PCR-positive swabs were culture confirmed. RT-PCR revealed 78% (298/382) of patients tested positive for C. pseudodiphtheriticum. Of patients positive for only C. diphtheriae, 63% (17/27) had severe disease compared to 55% (69/126) positive for both Corynebacterium species, and 38% (66/172) for only C. pseudodiphtheriticum. CONCLUSIONS: We report confirmation of a diphtheria outbreak and identification of a cocirculating Corynebacterium species. The high proportion of C. pseudodiphtheriticum codetection may explain why many suspected patients testing negative for C. diphtheriae presented with diphtheria-like symptoms. Published by Oxford University Press for the Infectious Diseases Society of America 2020.
Authors: Lingzi Xiaoli; Yanhui Peng; Margaret M Williams; Pamela K Cassiday; Sarah Nobles; Yvette Unoarumhi; Lauren M Weil; Tahmina Shirin; Zakir Hossain Habib; Maria Lucia Tondella; Michael R Weigand Journal: Microbiol Resour Announc Date: 2022-08-11