IS THE SALIVA DANGEROUS ?
When we are young, we learn
that tigers and sharks are dangerous animals. We might
be scared of them because they are big and powerful. As
we get older, however, we learn that sometimes the most dangerous animals are
also the smallest animals. In fact, the animal that kills the most people every
year is one that you have probably killed
yourself many times: the
mosquito.
While it may seem that all
mosquitoes are biters, this is not actually the case. Male mosquitoes eat plant nectar. On the other hand, female
mosquitoes feed on animal blood. They need this blood to live and produce eggs.
When a female mosquito bites a human being, it transmits a small amount of
saliva into the blood.
This saliva may or may not
contain a deadly disease. The result of the bite can be as
minor as an itchy bump or
as serious as death.
Because a mosquito can bite
many people in the course of its life, it can carry diseases from one person to
another very easily. Two of the most deadly diseases carried by mosquitoes are
malaria and yellow fever. More than 700 million people become sick from these
diseases every year. At least 2 million of these people will die from these
diseases.
Many scientists are working
on safer and better ways to kill mosquitoes, but so far, there is no sure way
to protect everyone in the world from their deadly bites. Mosquito nets can be
placed over beds to protect people against being bitten. These nets help people
stay safe at night, but they do not kill any mosquitoes. Mosquitoes have many
natural enemies like bats, birds, dragonflies, and certain kinds of fish.
Bringing more of these animals into places where mosquitoes live might help to
cut down the amount of mosquitoes in that area.
This is a natural solution, but it does not
always work very well. Mosquitoes can also be killed with poisons or sprays.
Even though these sprays kill mosquitoes, they may also harm other plants or
animals.
Although mosquitoes may not
seem as scary as larger, more powerful animals, they are far more dangerous to
human beings. But things are changing. It is highly likely that one day
scientists will find a way to keep everyone safe from mosquitoes and the
diseases they carry.
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