| Autor: | Lagos, Rosanna M.- Sikorski, Michael J.- Hormazábal, Juan Carlos- Fernandez, Alda- Duarte, Sergio- Pasetti, Marcela F.- Rasko, David A.- Higginson, Ellen- Nkeze, Joseph- Kasumba, Irene N.- Dougan, Gordon- Maes, Mailis- Lees, Andrew- Tennant, Sharon M.- Levine, Myron M. |
| Revista: | The Journal of Infectious Diseases |
| Año: | 2023 |
| Número: | |
| Paginas: | jiad585 |
| Volumen: | |
| Abstract: | OBJECTIVES: In Santiago, Chile, where typhoid had been hyperendemic (1977-1991), we investigated whether residual chronic carriers could be detected among household contacts of non-travel-related typhoid cases occurring 2017-2019. METHODS: Culture-confirmed cases were classified as "autochthonous" (domestically-acquired) versus "travel/immigration-related". Household contacts of cases had stool cultures and serum Vi antibody measurements to detect chronic Salmonella Typhi carriers. Whole genome sequences of acute cases and their epidemiologically-linked chronic carrier isolates were compared. RESULTS: Five of 16 autochthonous typhoid cases (31.3%) were linked to four chronic carriers in case households, two cases (onsets 23 months apart) were linked to the same carrier. Carriers were women aged 69-79 years with gallbladder dysfunction and Typhi fecal excretion, three had highly elevated serum anti-Vi titers. Genomic analyses revealed close identity (?11 core genome SNP [Single Nucleotide Polymorphism] differences) between case and epidemiologically-linked carrier isolates, all were genotypes prevalent in 1980s Santiago. A cluster of four additional autochthonous cases un-linked to a carrier was identified based on genomic identity (0-1 SNPs). Travel/immigration isolate genotypes were typical for the countries of travel/immigration. CONCLUSIONS: Although autochthonous typhoid cases in Santiago are currently rare, 5/16 such cases (31.3%) were linked to elderly chronic carriers identified among household contacts of cases. |
| Idioma: | eng |
| Base de Datos: | PubMed |
| Ver Más: | https://doi.org/10.1093/infdis/jiad585 |