Rapid genotyping protocol to improve dengue virus serotype 2 survey in Lao PDR

• Published in: PloS one 2020-08, Vol.15 (8), p.e0237384-e0237384
• Main Authors: Calvez, Elodie, Somlor, Somphavanh, Viengphouthong, Souksakhone, Balière, Charlotte, Bounmany, Phaithong, Keosenhom, Sitsana, Caro, Valerie, Grandadam, Marc
• Format: Article
• Language: English
• Subjects: Bacteriology; Biochemistry, Molecular Biology; Biology and Life Sciences; Computer and Information Sciences; Control; Dengue; Dengue fever; Dengue Virus; Diagnosis; Ecology, environment; Env gene; Envelope gene; Epidemics; Epidemiology; Fever; Gene polymorphism; Gene sequencing; Genomes; Genomics; Genotype & phenotype; Genotypes; Genotyping; Genotyping Techniques; Health; Health problems; Health screening; Health surveillance; Humans; Laos; Life Sciences; Low level; Medicine and Health Sciences; Methods; Microbiology and Parasitology; Molecular biology; Molecular diagnostic techniques; People and Places; Phylogenetics; Polymorphism; Provinces; Public health; Research and analysis methods; Santé publique et épidémiologie; Sentinel surveillance; Serotypes; Serotyping; Surveillance; Surveys and Questionnaires; Time Factors; Urban Population; Vector-borne diseases; Viral diseases; Virology; Viruses
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0237384

Dengue fever is one of the major public health problems in Lao PDR. Over the last decade, dengue virus (DENV) epidemics were characterized by a novel predominant serotype accompanied by at least two other serotypes. Since 2008, DENV-2 circulated at a low level in Lao PDR but its epidemiologic profile changed at the end of 2018. Indeed, the number of confirmed DENV-2 cases suddenly increased in October 2018 and DENV-2 became predominant at the country level in early 2019. We developed a Genotype Screening Protocol (GSP) to determine the origin(s) of the Lao DENV-2 and study their genetic polymorphism. With a good correlation with full envelope gene sequencing data, this molecular epidemiology tool evidence the co-circulation of two highly polymorphic DENV-2 genotypes, i.e. Asian I and Cosmopolitan genotypes, over the last five years, suggesting multiple introductions of DENV-2 in the country. GSP approach provides relevant first line information that may help countries with limited laboratory resources to reinforce their capabilities to DENV-2 and to follow the epidemics progresses and assess situations at the regional level.