Know How Mosquitoes Use Six Needles to Suck Your Blood

Summer and monsoon bring in worries for a lot of people, as the climate and environment indicates to the increase in number of mosquitoes, and therefore, the diseases spread by them. Mosquito-borne diseases have become a menace for everyone, from kids to elderly. While we might have often observed a mosquito when it bites us, not many of us, in fact, none of us might have noticed that it buries six needles into a human body to suck the blood.

There is a huge cry about mosquito bites; however, not all mosquitoes bite. Only female mosquitoes bite us, humans and animals, to drink our blood to grow their eggs, and seldom can leave behind viruses and parasites that cause diseases like West Nile, Zika, malaria and dengue.

Researchers believe that the effectiveness of mosquito bites determines how sick can they make a human. According to scientists, the mosquito’s mouth, called a proboscis (pronounced pro-BOSS-iss), isn’t just one tiny spear, but a sophisticated system of thin needles. Each needle pierces the skin of the host, finds blood vessels and makes it easy for mosquitoes to suck blood out of them.

As explained by University of California, Davis, parasitologist and entomologist Shirley Luckhart, mosquitoes have more than 150 receptors, which are proteins on their antennae and proboscis, helping them find victims or figure out if the water is nutritious enough to lay eggs in. The malaria-causing Anopheles mosquitoes track the carbon dioxide we exhale as we sleep. They detect body heat and substances called volatile fatty acids that waft up from our skin.

Scientists have discovered that when a mosquito’s proboscis pierces the skin, one of its six needles, called the labrum, uses receptors on its tip to find a blood vessel. “Those receptors responded to the chemicals in the blood,” explains UC Davis biochemist Walter Leal. The labrum then pierces the vessel and serves as a straw.

After a mosquito pierces the skin of the host, a flexible lip-like sheath called the labium scrolls up and stays outside as she pushes in six needle-like parts. Scientists refer to these parts as stylets. Later, two of these needles, called maxillae, have tiny teeth. The mosquito uses them to saw through the skin. Meanwhile, another set of needles, the mandibles, hold tissues apart while the mosquito works.

The sixth needle — called the hypopharynx — drips saliva into us which contains chemicals that keep our blood flowing.