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Vector Competence Analyses on Aedes aegypti Mosquitoes using Zika Virus
Published on: May 31, 2020
THE INCUBATION PERIOD OF YELLOW FEVER IN THE MOSQUITO
1Laboratories of the Commission on Yellow Fever, International Health Division of the Rockefeller Foundation, Lagos, Nigeria, West Africa.
Abstract:
1. The yellow fever virus was found in infectious form in Aedes aegypti throughout the entire period of the extrinsic incubation, as demonstrated by the injection of the bodies of mosquitoes into normal rhesus monkeys at daily intervals after the insects had fed on an infected animal. 2. The virus was transmitted through the bite of the mosquitoes, in one experiment on and after the 9th day, and in two experiments on the 12th day after the initial infecting feed. 3. The pathologic changes produced by the injection of the infected mosquitoes into normal monkeys during the extrinsic incubation were in every respect those of typical experimental yellow fever. 4. The monkeys withstand easily the subcutaneous injection of the mosquito emulsion. No acute inflammatory reaction was observed at the site of injection in any of the seventeen animals inoculated with this material in these three experiments.
Insights
Yellow fever virus infects Aedes aegypti mosquitoes and is transmitted via their bite starting around the 9th day. Infected mosquitoes cause typical yellow fever pathology in rhesus monkeys.
Area of Science:
- Virology
- Entomology
- Infectious Diseases
Background:
- Yellow fever is a severe hemorrhagic disease transmitted by mosquitoes.
- Understanding the extrinsic incubation period (EIP) of yellow fever virus in mosquitoes is crucial for vector control.
Purpose of the Study:
- To determine the infectious period of yellow fever virus within Aedes aegypti mosquitoes.
- To establish the time frame for virus transmission by infected mosquitoes.
Main Methods:
- Mosquitoes (Aedes aegypti) were fed on animals infected with yellow fever virus.
- Infectivity of mosquitoes was assessed daily by injecting mosquito homogenates into rhesus monkeys.
- Transmission efficiency was evaluated through mosquito bites on susceptible monkeys.
Main Results:
- Infectious yellow fever virus was present in Aedes aegypti throughout the extrinsic incubation period.
- Mosquito transmission occurred on or after the 9th day post-infection.
- Inoculation of monkeys with infected mosquitoes produced typical yellow fever pathology.
Conclusions:
- Aedes aegypti mosquitoes remain infectious for yellow fever virus throughout the EIP.
- Mosquito bite transmission is established by the 9th-12th day after initial infection.
- Experimental yellow fever in monkeys is reliably induced by infected mosquito material.
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