Evolution, heterogeneity and global dispersal of cosmopolitan genotype of Dengue virus type 2

Abstract

Dengue virus type 2 (DENV-2) contributes substantially to the dengue burden and dengue-related mortality in the tropics and sub-tropics. DENV-2 includes six genotypes, among which cosmopolitan genotype is the most widespread. The present study investigated the evolution, intra-genotype heterogeneity and dispersal of cosmopolitan genotype to understand unique genetic characteristics that have shaped the molecular epidemiology and distribution of cosmopolitan lineages. The spatial analysis demonstrated a wide geo-distribution of cosmopolitan genotype through an extensive inter-continental network, anchored in Southeast Asia and Indian sub-continent. Intra-genotype analyses using 3367 envelope gene sequences revealed six distinct lineages within the cosmopolitan genotype, namely the Indian sub-continent lineage and five other lineages. Indian sub-continent lineage was the most diverged among six lineages and has almost reached the nucleotide divergence threshold of 6% within E gene to qualify as a separate genotype. Genome wide amino acid signatures and selection pressure analyses further suggested differences in evolutionary characteristics between the Indian sub-continent lineage and other lineages. The present study narrates a comprehensive genomic analysis of cosmopolitan genotype and presents notable genetic characteristics that occurred during its evolution and global expansion. Whether those characteristics conferred a fitness advantage to cosmopolitan genotype in different geographies warrant further investigations.

Genetic Diversity of Dengue Virus in Clinical Specimens from Bangkok, Thailand, during 2018–2020: Co-Circulation of All Four Serotypes with Multiple Genotypes and/or Clades

“…The Asian I and Asian II genotypes circulate in Asia. The Cosmopolitan genotype exhibits a wide-spread distribution around the world [ 24 ]. The American genotype is predominant in and specific to Central and South America.…”

“…The sylvatic genotype is frequently found in non-human primates from African and southeast Asian forests. DENV-2 is known to be associated with severe dengue cases [ 24 , 25 ]. DENV-3 consists of five genotypes [ 26 ].…”

Emergence of Dengue Virus Serotype 2 Cosmopolitan Genotype, Brazil

“…The Asian-American genotype, also known as the Southeast Asian-American or genotype III, replaced the American genotype (DENV-2 genotype I) in the 1980s (5). The cosmopolitan genotype (DENV-2 genotype II) is the most widespread and genetically heterogeneous genotype (6). This genotype is circulating in Asia, the Middle East, the Pacific Islands, and Africa and contributes substantially to the global dengue burden (6).…”

Dengue-2 Cosmopolitan genotype detection and emergence in South America

“…The Asian/American genotype, also known as Southeast Asian-American or genotype III, replaced the American genotype (also known as DENV-2 genotype I) in the 80's (5). The Cosmopolitan genotype (also known as DENV-2 genotype II), is the most wide-spread and genetically heterogeneous genotype, currently circulating in Asia, Middle East, Pacific, and Africa contributing substantially to the dengue burden globally (6). The global dispersal of this genotype may have driven the extensive intra-genotypic diversity, potentially favoring the capacity for wide-spread expansion (6).…”

“…The Cosmopolitan genotype (also known as DENV-2 genotype II), is the most wide-spread and genetically heterogeneous genotype, currently circulating in Asia, Middle East, Pacific, and Africa contributing substantially to the dengue burden globally (6). The global dispersal of this genotype may have driven the extensive intra-genotypic diversity, potentially favoring the capacity for wide-spread expansion (6). Cosmopolitan lineages continue to expand geographically, with recent new introductions reported globally, such as in Asia and Africa (7,8).…”