WHY ARE MOSQUITOES SO OBSESSED WITH HUMANS?

All of us encounter a pesky mosquito from time to time. For most people, it’s little more than a momentary nuisance. A nip, a few days of itching, and we move on with our lives.

Many people don’t get by so easily, unfortunately. Each year, mosquito bites lead to the death of an estimated 1 million people — more than the population residing in cities as large as Mumbai or New Delhi. Many, many millions of additional people get tremendously sick from mosquito bites, even though they don’t pass away.

This widespread suffering is the result of mosquito borne diseases, viruses and parasites, like Malaria and Dengue that pass into our bloodstream when mosquitoes bite us. The most widespread of these diseases is Malaria, but recent outbreaks of Dengue Fever and Zika virus (now confirmed) to cause brain defects in infants, have brought renewed attention to the mosquito as a carrier and transmitter of deadly pathogens.

Accounting for this spread of disease, mosquitoes are actually, by a wide margin, the world’s deadliest insect, based on the number of human lives they take each year. One mosquito alone, can infect up to 100 people with a mosquito-borne disease!

So, why are humans their meal of choice?

The short answer is they rely upon the nourishment provided by human blood to reproduce. The full story is more complex — and it’s highlighted by a peculiar, distinctive relationship between humans and mosquitoes that has been endured over centuries and ignited pandemics the world over.

Once upon a time, thousands of years ago, mosquitoes fed on other non-human forest animals. Evolution led certain mosquitoes to develop a preference for feeding on humans; an attraction which research has demonstrated is largely based on the scent of human beings. Driven by this chemical attraction, we slowly became not only a feeding option for mosquitoes, but also their meal of choice. Unfortunately for us, these same species carry dangerous human diseases.

So, why mosquitoes are attracted to humans?

Anyone who has suffered through the pain and irritation of mosquito bites knows what troublesome pests mosquitoes can be. But what attracts mosquitoes to humans in the first place? Why is it that some people seem almost completely immune to these little buggers? Why, in a crowd, do mosquitoes tend to be partial to one victim over another?

WHY DO MOSQUITOES BITE?

Only female mosquitoes bite. They’ve evolved a proboscis, a long, tubular mouth, not unlike that seen on butterflies that can puncture the skin and suck blood. They seek to feed on blood to get the nutrients required to produce eggs. A male mosquito’s primary role is reproduction.

WHAT ARE MOSQUITOES ATTRACTED TO?

Mosquitoes are attracted to moist areas to breed and produce eggs. That’s why it’s very important to prevent standing water in your yard and other areas around your home.

WHAT ATTRACTS MOSQUITOES TO HUMANS?

· Your blood

As previously mentioned, female mosquitoes feed on blood in order to provide nutrients to their eggs.

· Your breath

In addition to a proboscis that can puncture human skin, female mosquitoes sport long antennae and olfactory (odor-sensing) organs called palps. These instruments are attuned to the odor of carbon dioxide, or CO2, which we produce every time we exhale. High concentrations of CO2, which mosquitoes can detect from more than 150 feet away, offer an initial temptation to hungry mosquitoes. However, CO2 isn’t the only determinant of who gets bitten, and how badly.

· Your smell

Entomologists at the University of California, Riverside, have determined that certain odors released via perspiration are more likely to attract mosquitoes. Substances such as uric acid, lactic acid and ammonia can also be released by bacteria that live in human skin. Moreover, the higher your body temperature, the more likely you are to sweat. These facts help to account for why mosquito bites will frequently be clustered around the feet, ankles, wrists and hands, as all these areas of the body tend to be exposed to the elements, to collect and retain moisture and to play host to larger bacterial colonies.

· Reasons completely beyond your control.

There is no single determining factor explaining why mosquitoes bite who they bite. Researchers in Japan have demonstrated that individuals with Type O blood are more likely to be bitten than individuals with Type A blood. Your metabolism, with its capacity to raise and lower your body temperature, is a factor as well. Scientists have established that an individual’s genetic make-up can account for 85 percent of the various factors that make them a “mosquito magnet”.

WHEN DO MOSQUITOES FEED?

Mosquitoes are most active during the hours of sunset and sunrise, but there are day biters, too.

DO MOSQUITOES BITE OTHER SPECIES?

Human beings aren’t alone in dealing with mosquitoes. Certain species attack birds, others mammals and some even selectively target fish and reptiles. However, in situations where a given species’ preferred food supply is low or threatened, the mosquito will not hesitate to be opportunistic and feed on whatever it can.

Regardless of whether mosquitoes have a taste for you or not, they’re more than a nuisance. If you’re concerned about medical symptoms associated with any of these conditions and suspect that they may be a result of a mosquito bite, consult your physician.

PS: Make sure you are insured!