What will happen and what to do if you are bitten by a malaria mosquito: about the likelihood of infection and treatment

Malaria mosquitoes are a species of dipteran insects that transmit malaria parasites. These parasites cause a serious disease in humans - malaria. Infection occurs during a bite.

Malaria mosquitoes live on all continents except Antarctica, but the most dangerous species live in subtropical and tropical countries.
In other regions, insects appear in places with high humidity and become active in the evening and at night. Does a lamp help against mosquitoes?
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If you suspect a malaria mosquito bite, you should immediately consult a doctor.

Appearance of insects

Long-legged mosquitoes are mistakenly considered malarial due to their large size. In fact, they feed on plants and pose no danger to humans.

Unlike ordinary species, malaria mosquitoes have long legs, jointed tentacles located on the head, and dark spots on the wings. At the moment of the bite, they raise their abdomen and hind legs.

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Let's consider why a malaria mosquito bite is dangerous, what are its signs and consequences.

Description of the genus Anopheles

Malaria mosquitoes (genus Anopheles)

The word anopheles means “harmful” in Greek. The malaria mosquito belonging to this genus is considered the carrier and source of the pathogen. The insect is potentially dangerous, that is, it infects only when its body contains the malaria parasite.

The genus Anopheles includes about 500 species. In the regions where malaria mosquitoes live, the climate is predominantly tropical and subtropical (Africa, Asia). There are 12 species of Anopheles found in Russia. Of these, 2 species can be carriers of malaria pathogens on the territory of the country, including A. common (A. maculipennis).

The body structure of Anopheles and the difference from the ordinary squeaking mosquito

Many people believe that malaria is transmitted by a large blood-sucking insect. Sometimes this role is “tried on” to the centipede. This two-winged creature, up to 6 cm long, resembles a mosquito in appearance. Only the centipede is completely harmless, does not bite humans, and does not carry infections.

Malaria mosquito (image 1)

What does a malaria mosquito look like (image 1):

slender body 6–14 mm long (in adults);
color brown or dark gray;
the head is small, with a thin proboscis;
wings narrow, transparent;
the hind legs are longer than the front ones.

Not many people know the difference between a malaria mosquito and a regular one, because they have not had to compare these two species. They lead a similar lifestyle and have a similar structure. What a malaria mosquito and an ordinary one look like also depends on the sex and ecotype of the insect, and the time of year. There are several noticeable distinguishing features.

How to distinguish a malaria mosquito from a regular one (squeaker):

Anopheles is 1.5 times larger;
The hind limbs are almost twice as long as the front pair;
The body is located at an angle of 45° to the substrate;
The head of the female malaria mosquito is equipped with two tentacles of the same length as the proboscis (oral apparatus) located between them.

The body of a sitting common mosquito is located almost parallel to the substrate or at a slight angle (the head is slightly higher than the abdomen). The legs of this species are approximately the same length. The tentacles on the female's head are 2–4 times shorter than the proboscis.

Read on the topic - Where do mosquitoes come from in the house and how to get rid of them

Reproduction, development, nutrition and distribution area of Anopheles

A sexually mature female analaria mosquito lays up to 200 eggs on the surface of the water every 2–3 days. After 1–4 weeks, larvae appear, which after a few molts turn into pupae.

Imagoes (adults) emerge from them. They live from 7 days to 3 months. Malaria mosquitoes need water bodies with filamentous algae to reproduce and develop. Three of the four stages of Anopheles development take place here.

Studying the needs of males and females will help you understand the question of what the malaria mosquito eats. Males have enough nectar from flowers and plant juices. Fertilized females need human blood, or rather, the available protein in its composition, to produce eggs.

Malaria mosquito larva

The larva of the malaria mosquito feeds on algae cells. Breathes atmospheric air entering through special openings. The pupa of the malaria mosquito has breathing tubes.

Anopheles is found on all continents except Antarctica and is absent in deserts. Where mosquitoes carry malaria, outbreaks of the disease are possible. Infection carriers remain viable at temperatures of 15–18°C; in countries with temperate climates they are active from April to October. Anopheles is found in the European part of Russia south of 60° N. sh., in Western Siberia. They live in the Far East, but do not carry malaria.

Symptoms and consequences of a bite

If you carefully analyze what a malaria mosquito bite looks like, you can conclude that it differs little from the bite of more familiar insects. Local allergic reactions occur on the skin.

Namely:

the appearance of a slight swelling;
local redness of the skin;
itching and burning sensation;
the appearance of blisters;
the formation of small seals under the skin.

Despite the potential danger, the bite of a malarial mosquito does not immediately cause significant pain or a sharp deterioration in health in a person. This makes an insect attack especially dangerous, since the patient may not pay attention to it and underestimate the danger of his condition.

The severity of the first symptoms is heterogeneous and depends on the individual health characteristics of the person and the type of insect attacked.

After a bite, the malarial plasmodium spreads through the blood and lymph throughout the body. Simultaneous infection of various organs and tissues occurs.

What happens if a malaria mosquito bites? Is malaria always inevitable?

It depends on the genetic characteristics of the person. May develop:

an allergic reaction at the site of the bite - the skin turns red, severe itching and burning occurs, in severe cases, suppuration and an increase in body temperature are possible;
urticaria - the appearance of itchy papules throughout the body;
general deterioration of health – nausea, vomiting, dizziness, rash on the body, fever;
malaria.

Outbreaks of malaria infection occur in regions with a warm climate: the territory of the North Caucasus, Central Asia. The disease can be registered in tourists arriving from countries in Africa, the Middle East, South America, and India.

Female

Malaria mosquitoes prefer to feed on blood; their diet also includes vegetation and plant sap. It is worth considering that only females drink blood; they use it to maintain full vital functions and for reproduction. But males do not attack people or animals; they consume only plant foods, plant nectar.

Females have a larger body than males, they are larger . Male and female individuals have antennae on the surface of the head, only in males they are equipped with processes and look like lush mustaches. But in females they are sensitive, capable of detecting heat from a mammal several kilometers away.

The purpose of female anopheles is to procreate. For these purposes, individuals use the blood of people and animals. After fertilization they lay eggs. After some time, larvae are formed from the eggs of the female malaria mosquitoes, they look like worms, then pupae appear, from which the imago is formed.

Why is malaria dangerous?

Malaria is one of the most dangerous infectious diseases, with a high mortality rate. The incubation period of the disease lasts from one week to a month. At this time, the symptoms of the disease are mild: the person experiences slight malaise, headache, nausea and chills.

Gradually, the severity of symptoms increases, periods of severe febrile excitement are replaced by temporary improvement. During the calm period, the patient falls asleep. During periods of improvement, he feels very weak. After 2-3 days, attacks of fever are repeated.

In addition to fever, as the main symptom of the disease, malaria is accompanied by cardiac arrhythmias, nausea and vomiting, aching joints, confusion, and delirium. The disease causes serious complications, such as cerebral edema, mental disorders, kidney problems, and coma.

Tropical malaria is considered the most dangerous, but its pathogens live only in countries located in the tropics.

Life cycle

The development cycle of the malaria mosquito covers several stages:

Egg;
Larva;
Pupa;
Imago or adult individual.

For full reproduction, insects require the presence of nearby bodies of water. After fertilization, the female lays eggs on the surface of the water. It is here that the main development of future offspring is observed.

On average, the period of maturation from egg to adult is from 4 days to 2 weeks. The malaria mosquito can remain in the adult stage for several months.

The period of development can be indicated by various conditions - climate, water temperature, availability of sufficient food. There must be normal lighting, a suitable temperature, and moderate humidity.

Actions after a bite

Although isolated outbreaks of infection are quite rarely diagnosed in our country, you need to learn what to do if you are bitten by a malaria mosquito. Not all types of these insects cause a dangerous form of malaria, but all cause negative sensations in the form of local reactions on the skin.

First aid algorithm:

wipe the affected area with alcohol or alcohol-containing liquids;
apply a cold compress to the bite site;
drink unsweetened tea;
if you are prone to allergic reactions, take an antihistamine;
applying products that eliminate itching, swelling and redness of the skin.

You should refrain from scratching the affected area. The resulting wounds become sites of secondary infection. If your condition worsens, chills and aching joints appear, you should definitely seek medical help.

Larva

The larva of the malaria mosquito is formed from eggs laid by the female. It resembles a caterpillar or worm. Its surface has a greenish tint, its body length is only 8 mm.

The head is small in size, but at the same time it is well developed. It has oral brushes that the creature uses for feeding. There is also a chest and abdomen, divided into segments. There are no limbs.

Compared to other types of mosquitoes, the larvae of malaria bloodsuckers do not have a respiratory siphon, so they float on the water parallel to the surface. They breathe using spiracles, which are located on the eighth segment.

They periodically float to the surface for a new portion of air.

Danger to human health and life

Diseases carried by malaria mosquitoes are the subject of research by scientists in many specialties. Malaria is the most common. More than a million children die from malaria every year in Africa. The main vector of tropical malaria is the Anopheles gambiae mosquito.
Another group of diseases, the second largest, is caused by threadworms. The malaria mosquito transfers them to healthy people through a bite after it drinks the blood of someone infected with microscopic worms. As a result, the victim's blood vessels become clogged and blood clots form. This promotes the accumulation of lymph in the legs or arms, and they swell to enormous sizes (“elephantiasis”). The record holders for mortality from these diseases are the countries of Africa, Asia and South America.
The last group of diseases includes tropical and yellow fevers and encephalitis.

Development

Like other mosquitoes, malaria mosquitoes go through the same stages of development: egg, larva, pupa and adult. In the first three stages, they develop in the water of various reservoirs and last a total of 7-14 days, depending on the type and ambient temperature. The lifespan of an imago is up to a month in the natural environment, even more in captivity, but in nature it most often does not exceed one or two weeks.

Females of different species lay 50-200 eggs. The eggs are placed one at a time on the surface of the water. They tend to float to the top of either side. Tolerant to drought. The larvae hatch within two to three days, but in colder areas hatching may be delayed for up to two to three weeks.

The development of larvae consists of four stages, or instars, at the end of which they turn into pupae. At the end of each stage, the larva sheds its old skin, or exoskeleton, that is, moults, in order to increase in size.

At the end of development in the pupal stage, the cephalothorax cracks and separates and an adult mosquito emerges from it.

The life cycle of a mosquito is associated with bodies of water, in which females lay eggs and the larvae develop to the stage of an adult insect. The larvae are classified as hyponeuston. They are attached on the dorsal side of the body to the lower surface of the film separating water and air with the help of special palm-shaped hairs. When feeding, the larva turns its head 180° and filters microscopic plankton using filter fans.

The optimal temperature, lower and upper temperature limits for the development of larvae depend on the species composition of mosquitoes. So Anopheles maculipennis

They are heat-loving insects and inhabit well-lit and sun-warmed water bodies; normal life activity of the larvae occurs at temperatures between 10 and 35 °C.
The optimal temperature is between 25-30 °C. An.
hyrcanus, larval development occurs within the range of 12–35 °C, with an optimum of 25–30 °C.
Anopheles claviger
usually breeds in shaded water bodies.
Temperature limits for development are 7–21 °C, optimal 14–16 °C. For An.
pulcherrimus favorable water bodies with average temperatures of 31–32 °C and maximum temperatures of 35–40 °C.
For Anopheles superpictus,
the optimal water temperature for the development of larvae is +30 °C, and the maximum is 35-38 °C [
source not specified 2660 days
].

Plasmodium, developing in the body of an infected victim, provokes the biosynthesis of volatile substances, the smell of which is attractive to female mosquitoes. Researchers came to this conclusion after conducting a series of experiments on mice. Malaria parasites changed the body odor of mice, and this odor became especially “attractive” to mosquitoes during the period of full maturation of the parasites.

Destruction of anafeles

An important measure to prevent and stop the spread of the disease is the destruction of anafeles in its habitat.

Where possible, ponds and swamps are drained or fish are introduced into them to kill mosquito larvae.

The dragonfly larva also copes with this task. South American toothy carp, perch and small bleak successfully fight against the brood of malaria mosquitoes in different regions.

A radical and not always justified measure is to spill oil in a thin layer over the surface of a reservoir. By disrupting gas exchange, oil contributes to the death of the larvae.

The most modern and safest method is to spray the drug in the form of dust over water bodies.

Settling on the surface of reservoirs, it destroys juvenile Anopheles without causing harm to other inhabitants.

The use of repellents near bodies of water will repel mosquitoes and blood-sucking midges.

Biological features

Malaria mosquitoes are dipterous insects that are practically no different from ordinary mosquitoes. The insect has a long and thin body, the size of which is 6-14 mm. The body color is dark gray or brown. There is a pair of transparent wings on the surface. The body is divided into distinct small segments. Stripes can be seen on the surface of the back.

The insect's head is small in size and has eyes on its surface. They have a scalloped structure and consist of many ommatidia . There are antennae on the front surface of the head. They provide smell recognition, and insects also use them for touch. Males have long and fluffy hairs on their antennae, while females have short and sparse hairs.

Insects have a pair of wings; they have an elongated oval shape. The surface has a large number of transverse and longitudinal veins, covered with microtrichia (small hairs). Malaria mosquitoes have 4 brown spots on the surface of their wings.

Oral apparatus

The oral apparatus of malaria mosquitoes is a kind of proboscis.

It has the following parts:

Upper and lower lip;
Hypopharynx (subpharynx);
A pair of upper jaws - mandibles;
Pair of lower jaws - maxillary.

The lower lip is a tube. It is a support for stabbing stilettos. It is through this that blood passes during suction. As mentioned above, only females consume blood; they use it for full life activity and reproduction. It is considered a nutritional component for egg maturation.

5-segmented palps are used as organs of touch and taste, which extend from the base of the jaws. In malaria mosquitoes, the palps and proboscis are of equal length, and club-shaped thickenings are provided at the ends.

What does the malaria mosquito eat?

Photo: Large malaria mosquito

The females of these insects feed on blood, but not constantly; for example, after laying eggs, they switch to flower nectar, and this period is the safest for potential victims of a blood-sucking insect. Males never feed on blood; they prefer the same nectar of flowering plants. Having bitten a person with malaria, Anopheles becomes its carrier. For parasites, the mosquito is the main host, and the vertebrate is only an intermediate host.

Anopheles can overwinter as fertilized females. Inside the female, malarial plasmodia cannot survive the winter, so the first mosquitoes after winter are not carriers of malaria. In order for a female malaria mosquito to infect again, it needs to drink the blood of a malaria patient and then live for a couple of weeks for the parasites to form inside it. In Russian conditions, this is unlikely; moreover, more than half of the females die within four days after being bitten by someone infected with malaria.

Interesting fact: Anopheles makes about 600 wing beats within one second, which are perceived by humans as a squeak. The sound made when flying by males and females differs in pitch; adult individuals also squeak lower than young ones. The flight speed of a malaria mosquito exceeds more than 3 km per hour.

Population and species status

Photo: Malaria mosquito

Due to its phenomenal fertility and ability to survive even in conditions extremely unfavorable for insects, the status of the Anopheles species is stable, even despite the huge number of natural enemies in their habitats. The situation may change somewhat in the near future, when the latest genetic weapons will be used in the fight against these blood-sucking creatures. When old methods of combating malaria mosquitoes are used, their population is restored in a short time, again claiming hundreds of thousands of human lives. It is not for nothing that the word “anopheles” is translated as useless or harmful, since these creatures do not bring any benefit, only causing enormous harm.

After the elimination of malaria on the territory of the USSR in the mid-20th century, all of Russia found itself outside the range of malaria. In subsequent years, only imported cases of all types of malaria from other territories were recorded. In the 90s, due to the huge migration of the population and the lack of sufficient means to combat malaria, there was a surge in incidence throughout the post-Soviet space. Later, this disease was imported from Tajikistan and Azerbaijan, where malaria epidemics occurred several times. Today the situation is favorable.

Despite the fact that the malaria mosquito mainly lives in hot countries, everyone should know the danger it poses and how to effectively protect itself from it. There are several reasons for this: firstly, due to climate change, these insects are inhabiting more and more new territories and may soon appear in the most unexpected places, and secondly, tourism to exotic countries is developing more and more actively every year.

Prevention measures

For those who live in areas with an unfavorable situation regarding malaria and travelers to tropical countries, the best solution is vaccination and taking antimalarial drugs.

Mosquito nets will protect your house or apartment from mosquitoes and other insects. In endemic areas, it is recommended to regularly treat the net with insecticides.

When going on a hike, it is important to protect exposed parts of the body from bloodsuckers and spray the skin and clothing.

The risk of attack by Anopheles is not high. They hide during the day and come out to hunt at dusk. During the day they are not active, which means walking is not dangerous.

Aerosols, creams, bracelets, and pencils are used to protect against insects. The drugs are designed to repel insects. A popular remedy is a spray or aerosol. But since chemicals are toxic, there is a risk of developing allergies. Protection against insects lasts about 4 hours.

Gels and creams protect against pests for 8 hours, the disadvantage is that they can stain clothes. The risk of developing allergies is 20%.

Since insects are afraid of smoke, it is better to spend the evening and night near the fire.

When encountering malarial mosquitoes, there is no need to panic, but you should not underestimate the enemy. Sometimes the consequences are catastrophic.