Host and viral features of human dengue cases shape the population of infected and infectious Aedes aegypti mosquitoes.
Nguyet MN., Duong THK., Trung VT., Nguyen THQ., Tran CNB., Long VT., Dui LT., Nguyen HL., Farrar JJ., Holmes EC., Rabaa MA., Bryant JE., Nguyen TT., Nguyen HTC., Nguyen LTH., Pham MP., Nguyen HT., Luong TTH., Wills B., Nguyen CVV., Wolbers M., Simmons CP.
Dengue is the most prevalent arboviral disease of humans. The host and virus variables associated with dengue virus (DENV) transmission from symptomatic dengue cases (n = 208) to Aedes aegypti mosquitoes during 407 independent exposure events was defined. The 50% mosquito infectious dose for each of DENV-1-4 ranged from 6.29 to 7.52 log10 RNA copies/mL of plasma. Increasing day of illness, declining viremia, and rising antibody titers were independently associated with reduced risk of DENV transmission. High early DENV plasma viremia levels in patients were a marker of the duration of human infectiousness, and blood meals containing high concentrations of DENV were positively associated with the prevalence of infectious mosquitoes 14 d after blood feeding. Ambulatory dengue cases had lower viremia levels compared with hospitalized dengue cases but nonetheless at levels predicted to be infectious to mosquitoes. These data define serotype-specific viremia levels that vaccines or drugs must inhibit to prevent DENV transmission.