May 15, 2024

Bad News: Light Pollution Could Extend Mosquito Season

This study and earlier findings by Meuti and her associates are among the first to reveal that artificial light during the night might have a substantial effect on mosquito behavior– consisting of impacts that arent always predictable.
” Were discovering that the same urban light during the night can have extremely various results under different seasonal contexts,” she said.
Meuti performed the research study with first author Matthew Wolkoff and Lydia Fyie, both Ph.D. prospects in entomology at Ohio State. The research study was published just recently in the journal Insects.
Diapause for female Northern home mosquitoes (Culex pipiens) is not rather a winter rest, however rather a duration of inactivity when the bugs live in caves, culverts, sheds and other semi-protected places. Prior to winters arrival, mosquitoes transform sugary sources, such as plant nectar, into fat. As days get longer, women begin foraging for blood meals to allow egg production. Some get contaminated with the West Nile infection by feeding upon contaminated birds, and later on send the virus when they eat individuals, horses, and other mammals.
This study builds upon 2 previous findings from Meutis lab: For her argumentation, Meuti found that circadian clock genes differ in between diapausing and non-diapausing mosquitoes, highly recommending that day length determines when diapause ought to start. And more recent work led by Fyie discovered that female mosquitoes exposed to dim light during the night averted diapause and ended up being reproductively active– even when brief days showed they ought to be inactive.
In the existing research study authored by Wolkoff, the researchers pursued both lines of questions, comparing everyday activity and nutrient build-up by mosquitoes reared in two laboratory conditions– long days simulating the bugs active season and short days that caused dormancy– with and without direct exposure to artificial light at night.
The research study offered more evidence connected with a circadian pattern to mosquito behavior, showing that pests activity reduces during diapause, but the circadian rhythmicity of that activity is sustained even during this inactive period.
The introduction of synthetic light at night was found to affect those activity patterns and to influence mosquitoes acquisition of nutrient reserves needed for fattening up and weathering winter temperatures.
Direct exposure to light pollution suppressed the amount of water-soluble carbohydrates– sugars that are a vital food source throughout winter season– that were accumulated by mosquitoes in both long- and short-day conditions. Patterns of build-up of the sugar glycogen were reversed by direct exposure to synthetic light during the night: Under typical conditions, non-dormant mosquitoes had great deals of glycogen in their bodies but diapausing bugs did not– however in mosquitoes subjected to light pollution, the long-day mosquitoes didnt build up much glycogen and short-day mosquitoes showed an increase in glycogen accumulation.
The researchers observed constant patterns in activity-related results of light at night, with a little increased activity among the inactive mosquitoes and somewhat suppressed activity among long-day mosquitoes anticipated to be busy looking for food. Though the findings werent statistically substantial, Wolkoff said the combined observations suggest light pollution causes mosquitoes to ward off diapause– possibly by scrambling signals from their circadian clock.
” This could be bad for mammals in the brief term since mosquitoes are possibly biting us later in the season, however it could likewise be bad for mosquitoes in the long term due to the fact that they might be failing to totally engage in preparatory activities they need to survive the winter throughout diapause, which may minimize their survival rate,” Wolkoff said.
The researchers plan to bring out field studies to see if these laboratory findings apply in the wild.
Recommendation: “Light Pollution Disrupts Seasonal Differences in the Daily Activity and Metabolic Profiles of the Northern House Mosquito, Culex pipiens” by Matthew Wolkoff, Lydia Fyie and Megan Meuti, 10 January 2023, Insects.DOI: 10.3390/ insects14010064.
This work was funded by the National Science Foundation, state and federal funds appropriated to Ohio States College of Food, Agricultural and Environmental Sciences, and the U.S. Department of Agriculture National Institute of Food and Agriculture.

West Nile Virus is a viral health problem that is infected human beings through the bite of infected mosquitoes. It was first identified in the West Nile district of Uganda in 1937 and has given that been reported in lots of nations, consisting of the United States. Symptoms of the virus can range from mild, flu-like symptoms to serious neurological symptoms such as sleeping sickness or meningitis.
Nevertheless, theres also good news– the disease-carrying bugs might not make it through the winter season.
A recent research study has actually exposed that city light pollution might interfere with the winter inactivity duration of mosquitoes responsible for transferring West Nile infection, presenting a mixed result of both favorable and negative ramifications.
If their attempts to fatten up are unsuccessful, the good news is that the insects that carry illness may not make it through the winter. The problem is that their inactive phase, called diapause, might be postponed, leading to them biting human beings and animals longer into fall.
” We see the highest levels of West Nile infection transmission in the late summertime and early fall in Ohio. If you have mosquitoes delaying or holding off diapause and continuing to be active longer in the year, thats at a time when the mosquitoes are most likely to be infected with West Nile infection and people could be at biggest threat of contracting it,” stated Megan Meuti, senior author of the research study and an assistant teacher of entomology at The Ohio State University.

West Nile Virus is a viral disease that is spread to human beings through the bite of infected mosquitoes. Symptoms of the virus can range from moderate, flu-like symptoms to serious neurological symptoms such as encephalitis or meningitis.
Diapause for female Northern house mosquitoes (Culex pipiens) is not rather a winter sleep, but rather a duration of dormancy when the pests live in caverns, culverts, sheds and other semi-protected areas. Prior to winter seasons arrival, mosquitoes convert sugary sources, such as plant nectar, into fat. Some get infected with the West Nile virus by feeding on infected birds, and later transfer the virus when they feed on people, horses, and other mammals.