Dengue Literature Review

Aedes aegypti

5 min read

Aedes aegypti

Overview

Aedes aegypti is the primary mosquito vector for dengue virus transmission. It is an urban-adapted species that preferentially bites humans and breeds in small standing water containers. It is the principal vector across tropical and subtropical regions where dengue is endemic or epidemic.

Key Points from Literature

Vector biology (Guzman2016)

  • Becomes infective after taking a blood meal from a viraemic patient during the viraemic window (24–48h before fever onset through ~day 5 of illness); viraemic persons — including asymptomatic individuals — can infect feeding mosquitoes (see Guzman2016 - Dengue Infection)
  • Extrinsic incubation period: 5–12 days in the mosquito (blood meal to virus reaching salivary glands); generally 8–10 days; once infected, the mosquito remains infective for life
  • Intrinsic incubation period (human infection to fever): 3–14 days (average 4–7 days)
  • Urban-adapted; preferential human biter; breeds in small peridomestic water containers (vases, tyres, gutters); highly susceptible to indoor residual spraying and larval source reduction

Differential DENV-2 replication by genotype (Bhatt2020)

The Asian genotype of DENV-2 replicates more efficiently in Ae. aegypti salivary glands than the American DENV-2 genotype (see Bhatt2020 - Dengue Pathogenesis Review). Salivary gland replication efficiency is a key determinant of transmission potential — only virus that successfully disseminates from the midgut to the salivary glands can be transmitted to a new human host during a subsequent blood meal. This genotype-specific differential explains in part why the Southeast Asian DENV-2 genotype is epidemiologically more aggressive (higher transmission rate, higher epidemic potential) than the American genotype, even when other host and environmental factors are held constant.

Vector control programmes

  • Cuba: insecticide spraying programme initiated 1981 after the DENV-2 epidemic; combined larval source reduction, adulticidal spraying, and community engagement (same three pillars as Singapore); epidemic dengue successfully controlled for ~30 years until the programme failed due to economic difficulties and re-introduction (see Guzman2016 - Dengue Infection)
  • Singapore: year-round surveillance and control programme with statutory enforcement; sustained multi-decade dengue control despite high-density urban population (see Guzman2016 - Dengue Infection)
  • Wolbachia (wMel): endosymbiotic bacterium suppresses DENV replication in Ae. aegypti and shortens mosquito lifespan; cytoplasmic incompatibility spreads wMel through mosquito populations without continuous releases; sustainable biological control approach (see Wolbachia)
  • Sterile insect technique (SIT): releases of radiation-sterilised male Ae. aegypti to suppress wild female reproduction; field trials conducted in Asia and the Americas; requires sustained releases but leaves no genetic modification in the environment (see Guzman2016 - Dengue Infection)

Multi-arbovirus vector role and co-transmission (Farias2024)

Farias2024 - Dengue Mimickers (narrative review, Brazil) expands the vector context:

  • Ae. aegypti transmits all four DENV serotypes, YFV, CHIKV, and ZIKV
  • Both Ae. aegypti and Ae. albopictus, when co-infected with DENV and CHIKV, can replicate and disseminate both viruses independently
  • Co-transmission in single bite documented — a mosquito co-infected with two arboviruses can transmit both simultaneously in a single bite; this is the mechanistic basis for observed clinical coinfections
  • Ae. aegypti is theoretically incapable of co-infection with YFV when already carrying DENV (and vice versa), per a competition/exclusion hypothesis in some Asian countries — proposed as a mechanism limiting DEN-YFV coinfection despite geographic overlap
  • Brazil co-circulates DENV, CHIKV, ZIKV, OROV, and MAYV — all transmitted by Ae. aegypti or closely related species, making co-infection a realistic differential diagnosis consideration during epidemics (narrative review — secondary source)

Contradictions & Debates

None yet recorded.

Sources

Graph View

Backlinks