UC Santa Barbara Scientists Discover How Mosquitoes Use Infrared Radiation to Find Hosts
Scientists at UC Santa Barbara have made an important discovery about how Aedes aegypti mosquitoes 🦟, which spread diseases like dengue and malaria, find their hosts. They found that these mosquitoes use infrared radiation, along with other senses, to locate humans and animals. This breakthrough could help create better mosquito control methods and reduce the spread of deadly diseases.
The Deadly Impact of Mosquitoes
While many people think of mosquito bites as just a minor irritation, in many parts of the world, mosquito bites can lead to serious and even deadly diseases. Aedes aegypti mosquitoes are responsible for spreading viruses that cause more than 100 million cases of illnesses like dengue, yellow fever, and Zika each year. Another mosquito species, Anopheles gambiae, is known for spreading malaria, a disease that causes over 400,000 deaths every year according to the World Health Organization. These tiny insects are considered the deadliest animals on Earth because of their ability to transmit diseases.
How Mosquitoes Find Their Hosts
Female mosquitoes need blood to develop their eggs, which is why they seek out humans and animals. Scientists have been studying how mosquitoes find their hosts for over 100 years. They’ve learned that mosquitoes don’t rely on just one sense but use a combination of cues to locate their targets. These cues include carbon dioxide (CO2) from our breath, odors from our bodies, body heat, and even humidity.
New Discovery: Infrared Radiation Detection
Recent research led by UC Santa Barbara has added a new sense to the list: infrared radiation detection. The study found that when infrared radiation, which is about the same temperature as human skin, is combined with CO2 and human odors, it doubles the mosquitoes’ efforts to find a host. The mosquitoes were strongly attracted to the infrared source, showing that they use this radiation to navigate and locate potential hosts. The research was detailed in the journal Nature.
How Mosquitoes Detect Infrared Radiation
Mosquitoes can detect infrared radiation from a distance of up to 70 centimeters (about 2.5 feet). The researchers discovered that mosquitoes have special sensors at the tips of their antennae that allow them to detect this radiation. These sensors are called TRPA1, which are temperature-sensitive proteins. When the infrared radiation hits these sensors, it heats them up, and the mosquitoes can sense this change, helping them find warm-blooded hosts.
Understanding the Role of TRPA1 and Rhodopsins
The study also explored how mosquitoes use proteins called rhodopsins to help detect temperature changes. Rhodopsins are usually known for detecting light, but in mosquitoes, some of these proteins are sensitive to small increases in temperature. The researchers found that two specific rhodopsins, called Op1 and Op2, are present in the same neurons as TRPA1. These rhodopsins help extend the range of the mosquito’s infrared detection, making it more effective at finding hosts even from a distance.
Implications for Mosquito Control and Global Health
Mosquitoes pose a serious threat to global health, with half the world’s population at risk of mosquito-borne diseases. The spread of these diseases is expected to increase as climate change and global travel allow mosquitoes like Aedes aegypti to expand their range into new areas, including parts of the United States where they were not found before.
The discovery of mosquitoes’ ability to detect infrared radiation could lead to improved mosquito control methods. For example, mosquito traps could be designed to include infrared sources that mimic the temperature of human skin, making them more attractive to mosquitoes. Additionally, this research helps explain why loose-fitting clothing can be effective in preventing mosquito bites. Loose clothing allows infrared radiation to dissipate between the skin and the fabric, making it harder for mosquitoes to detect and reach their host.
The Future of Mosquito Control
Understanding how mosquitoes detect their hosts opens up new possibilities for controlling these dangerous insects. With further research, scientists hope to develop even more effective methods to reduce the spread of diseases like dengue, malaria, and Zika. By targeting the specific ways mosquitoes use their senses, including infrared radiation, researchers can create traps and repellents that better protect people from these deadly pests.
In summary, the work done by UC Santa Barbara scientists has provided new insights into how mosquitoes, particularly Aedes aegypti, find their hosts using infrared radiation. This discovery not only adds to our understanding of mosquito behavior but also holds promise for improving global health by finding new ways to control mosquito populations and reduce the spread of life-threatening diseases.