What are the main symptoms of malaria. How is malaria transmitted. What are the risk factors for developing malaria. How can malaria be prevented and treated. What are the potential complications of malaria.

Understanding Malaria: A Global Health Concern

Malaria, a potentially life-threatening disease, continues to be a significant global health challenge. This parasitic infection, transmitted through the bites of infected mosquitoes, affects millions of people worldwide, particularly in tropical and subtropical regions. Despite ongoing efforts to combat the disease, malaria remains a leading cause of illness and death in many parts of the world.

The World Health Organization (WHO) reports that in recent years, nearly 290 million people are infected with malaria annually, resulting in over 400,000 deaths. These staggering numbers underscore the urgent need for continued research, prevention strategies, and treatment options to combat this persistent threat to public health.

The Malaria Parasite: Plasmodium

Malaria is caused by parasites belonging to the genus Plasmodium. There are several species of Plasmodium that can infect humans, with the most common and dangerous being:

• Plasmodium falciparum
• Plasmodium vivax
• Plasmodium ovale
• Plasmodium malariae
• Plasmodium knowlesi

Each species has unique characteristics and can cause varying degrees of severity in malaria infections. P. falciparum is responsible for the majority of severe cases and deaths, particularly in sub-Saharan Africa.

The Transmission Cycle of Malaria

Understanding the transmission cycle of malaria is crucial for developing effective prevention and control strategies. How exactly does malaria spread from person to person? The process involves a complex interplay between the Plasmodium parasite, mosquitoes, and human hosts.

The Mosquito Vector

Female Anopheles mosquitoes serve as the primary vectors for malaria transmission. When an infected mosquito bites a human, it injects sporozoites (the infective stage of the parasite) into the bloodstream. These sporozoites quickly travel to the liver, where they multiply and mature.

The Human Host

Once the parasites mature in the liver, they re-enter the bloodstream and infect red blood cells. This stage marks the beginning of the symptomatic phase of malaria. As the parasites multiply within the red blood cells, they cause the cells to burst, releasing more parasites into the bloodstream and continuing the cycle of infection.

Completing the Cycle

When an uninfected mosquito bites a person with malaria, it ingests the parasites along with the blood meal. The parasites then undergo further development within the mosquito, eventually migrating to the salivary glands. This completes the cycle, as the infected mosquito can now transmit the parasite to another human host during its next blood meal.

Recognizing Malaria Symptoms: What Does It Feel Like?

Malaria symptoms can vary in intensity and duration, depending on factors such as the specific Plasmodium species involved and the individual’s immune status. Typically, symptoms begin to appear 10 to 15 days after the infected mosquito bite. However, some parasite species can remain dormant in the liver for months or even years before causing symptoms.

The classic symptoms of malaria often include:

• High fever (often cyclical)
• Chills and shivering
• Profuse sweating
• Headache
• Fatigue
• Muscle and joint pain
• Nausea and vomiting
• Abdominal pain
• Diarrhea
• Anemia
• Jaundice (yellowing of the skin and eyes)

In some cases, particularly with P. falciparum infections, malaria can progress rapidly to severe illness, potentially leading to organ failure, coma, and death if left untreated.

The Malaria “Attack”

Many people with malaria experience a characteristic pattern of symptoms known as a malaria “attack.” This typically involves three distinct stages:

1. Cold stage: The person experiences sudden chills and shivering, often lasting for an hour or more.
2. Hot stage: The chills are followed by a high fever, often accompanied by severe headache, nausea, and vomiting. This stage can last for several hours.
3. Sweating stage: The fever breaks, and the person experiences profuse sweating as their body temperature returns to normal. This stage is often accompanied by extreme fatigue.

These attacks may occur every 48 to 72 hours, depending on the specific Plasmodium species causing the infection.

Risk Factors: Who is Most Vulnerable to Malaria?

While anyone can contract malaria if exposed to infected mosquitoes, certain groups are at higher risk of developing severe disease or complications. Understanding these risk factors is essential for targeted prevention and treatment strategies.

Geographical Risk

The primary risk factor for malaria is living in or traveling to areas where the disease is endemic. These regions include:

• Sub-Saharan Africa
• South and Southeast Asia
• Pacific Islands
• Central America
• Northern South America

The level of risk can vary depending on factors such as local malaria control efforts, seasonal changes in transmission rates, and individual preventive measures taken.

High-Risk Groups

Certain populations are more susceptible to severe malaria infections:

• Young children and infants
• Pregnant women
• Elderly individuals
• People with weakened immune systems (e.g., HIV/AIDS patients)
• Travelers from non-endemic areas

These groups may experience more severe symptoms and are at higher risk of complications, making early diagnosis and treatment crucial.

Socioeconomic Factors

In many malaria-endemic countries, socioeconomic factors contribute to increased risk. Limited access to healthcare, preventive measures, and education about the disease can exacerbate the impact of malaria on vulnerable populations.

Malaria Prevention: Strategies for Protecting Yourself

Preventing malaria involves a multi-faceted approach, combining personal protective measures, environmental controls, and medication when appropriate. What are the most effective ways to reduce your risk of contracting malaria?

Vector Control

Reducing exposure to mosquito bites is a crucial component of malaria prevention. Effective vector control measures include:

• Using insecticide-treated bed nets (ITNs)
• Indoor residual spraying (IRS) of insecticides
• Wearing protective clothing (long sleeves, pants)
• Using mosquito repellents containing DEET or other approved ingredients
• Eliminating mosquito breeding sites by removing standing water

Chemoprophylaxis

For travelers to malaria-endemic areas, antimalarial medications can be prescribed as a preventive measure. Common chemoprophylactic drugs include:

• Atovaquone-proguanil (Malarone)
• Doxycycline
• Mefloquine
• Chloroquine (in areas without chloroquine-resistant parasites)

It’s important to consult with a healthcare provider to determine the most appropriate medication based on your destination, duration of stay, and individual health factors.

Vaccination

In a significant development, the World Health Organization has recently recommended the use of the RTS,S/AS01 malaria vaccine for children in regions with moderate to high P. falciparum transmission. While not 100% effective, this vaccine represents a major step forward in malaria prevention efforts.

Diagnosis and Treatment: Combating Malaria Infections

Early and accurate diagnosis of malaria is crucial for effective treatment and preventing complications. How is malaria diagnosed, and what treatment options are available?

Diagnostic Methods

Several diagnostic techniques are used to detect malaria infections:

• Microscopy: Examining blood smears under a microscope to identify parasites
• Rapid Diagnostic Tests (RDTs): Quick and easy-to-use tests that detect specific malaria antigens
• Polymerase Chain Reaction (PCR): Molecular testing for parasite DNA, particularly useful for low-level infections

Treatment Approaches

Malaria treatment typically involves antimalarial medications to eliminate the parasites from the bloodstream. The choice of treatment depends on factors such as:

• The specific Plasmodium species causing the infection
• The severity of symptoms
• The patient’s age and pregnancy status
• Local patterns of drug resistance

Common antimalarial drugs used for treatment include:

• Artemisinin-based combination therapies (ACTs)
• Chloroquine (for P. vivax and P. ovale infections in areas without resistance)
• Quinine
• Primaquine (to prevent relapses in P. vivax and P. ovale infections)

In severe cases, intravenous antimalarial drugs and supportive care may be necessary.

Complications of Malaria: Understanding the Risks

While many cases of malaria can be successfully treated, the disease can lead to severe complications, particularly when caused by P. falciparum or when treatment is delayed. What are the potential complications of malaria, and why are they so dangerous?

Cerebral Malaria

One of the most severe complications of malaria is cerebral malaria, which occurs when parasite-infected red blood cells block small blood vessels in the brain. This can lead to:

• Swelling of the brain
• Seizures
• Coma
• Permanent neurological damage
• Death, if left untreated

Severe Anemia

Malaria can cause severe anemia due to the destruction of red blood cells and suppression of new red blood cell production. This can lead to:

• Extreme fatigue
• Shortness of breath
• Rapid heartbeat
• Organ damage due to inadequate oxygen supply

Respiratory Distress

In some cases, malaria can cause acute respiratory distress syndrome (ARDS), a severe lung condition that can lead to:

• Difficulty breathing
• Low blood oxygen levels
• Pulmonary edema (fluid in the lungs)

Other Complications

Additional severe complications of malaria can include:

• Kidney failure
• Liver failure
• Splenic rupture
• Hypoglycemia (low blood sugar)
• Cardiovascular collapse

These complications underscore the importance of prompt diagnosis and treatment of malaria infections.

The Future of Malaria Control: Research and Innovation

Despite the challenges posed by malaria, ongoing research and innovation offer hope for improved prevention, diagnosis, and treatment strategies. What are some of the promising developments in the fight against malaria?

Vaccine Development

The RTS,S/AS01 vaccine represents a significant milestone in malaria prevention, but research continues on developing more effective vaccines. Some areas of focus include:

• Whole-parasite vaccines
• Transmission-blocking vaccines
• Multi-stage, multi-antigen vaccines

Novel Drug Development

With the emergence of drug-resistant parasites, there is an ongoing need for new antimalarial medications. Researchers are exploring:

• New classes of antimalarial compounds
• Combination therapies to combat resistance
• Long-acting injectable formulations for chemoprevention

Vector Control Innovations

Advances in vector control strategies aim to reduce mosquito populations and prevent transmission. Some innovative approaches include:

• Genetically modified mosquitoes
• Attractive toxic sugar baits
• Spatial repellents
• Improved insecticide-treated materials

Diagnostic Advancements

Efforts to improve malaria diagnosis focus on developing more sensitive, specific, and field-friendly tools, such as:

• Highly sensitive rapid diagnostic tests
• Portable molecular diagnostic devices
• AI-assisted microscopy

These advancements in research and innovation offer hope for a future where malaria is no longer a major global health threat. However, continued investment, collaboration, and commitment from the international community are essential to translate these promising developments into real-world impact.

As we continue to learn more about malaria and develop new strategies to combat it, the global health community remains committed to the goal of malaria elimination. By combining innovative research, effective prevention measures, and accessible treatment options, we can work towards a world where malaria no longer claims hundreds of thousands of lives each year.

Malaria – Symptoms & causes

Overview

Malaria is a disease caused by a parasite. The parasite is spread to humans through the bites of infected mosquitoes. People who have malaria usually feel very sick with a high fever and shaking chills.

While the disease is uncommon in temperate climates, malaria is still common in tropical and subtropical countries. Each year nearly 290 million people are infected with malaria, and more than 400,000 people die of the disease.

To reduce malaria infections, world health programs distribute preventive drugs and insecticide-treated bed nets to protect people from mosquito bites. The World Health Organization has recommended a malaria vaccine for use in children who live in countries with high numbers of malaria cases.

Protective clothing, bed nets and insecticides can protect you while traveling. You also can take preventive medicine before, during and after a trip to a high-risk area. Many malaria parasites have developed resistance to common drugs used to treat the disease.

Products & Services

Symptoms

Signs and symptoms of malaria may include:

• Fever
• Chills
• General feeling of discomfort
• Headache
• Nausea and vomiting
• Diarrhea
• Abdominal pain
• Muscle or joint pain
• Fatigue
• Rapid breathing
• Rapid heart rate
• Cough

Some people who have malaria experience cycles of malaria “attacks.” An attack usually starts with shivering and chills, followed by a high fever, followed by sweating and a return to normal temperature.

Malaria signs and symptoms typically begin within a few weeks after being bitten by an infected mosquito. However, some types of malaria parasites can lie dormant in your body for up to a year.

When to see a doctor

Talk to your doctor if you experience a fever while living in or after traveling to a high-risk malaria region. If you have severe symptoms, seek emergency medical attention.

Causes

Malaria is caused by a single-celled parasite of the genus plasmodium. The parasite is transmitted to humans most commonly through mosquito bites.

Mosquito transmission cycle

Malaria transmission cycle

Malaria spreads when a mosquito becomes infected with the disease after biting an infected person, and the infected mosquito then bites a noninfected person. The malaria parasites enter that person’s bloodstream and travel to the liver. When the parasites mature, they leave the liver and infect red blood cells.

• Uninfected mosquito. A mosquito becomes infected by feeding on a person who has malaria.
• Transmission of parasite. If this mosquito bites you in the future, it can transmit malaria parasites to you.
• In the liver. Once the parasites enter your body, they travel to your liver — where some types can lie dormant for as long as a year.
• Into the bloodstream. When the parasites mature, they leave the liver and infect your red blood cells. This is when people typically develop malaria symptoms.
• On to the next person. If an uninfected mosquito bites you at this point in the cycle, it will become infected with your malaria parasites and can spread them to the other people it bites.

Other modes of transmission

Because the parasites that cause malaria affect red blood cells, people can also catch malaria from exposure to infected blood, including:

• From mother to unborn child
• Through blood transfusions
• By sharing needles used to inject drugs

Risk factors

The greatest risk factor for developing malaria is to live in or to visit areas where the disease is common. These include the tropical and subtropical regions of:

• Sub-Saharan Africa
• South and Southeast Asia
• Pacific Islands
• Central America and northern South America

The degree of risk depends on local malaria control, seasonal changes in malaria rates and the precautions you take to prevent mosquito bites.

Risks of more-severe disease

People at increased risk of serious disease include:

• Young children and infants
• Older adults
• Travelers coming from areas with no malaria
• Pregnant women and their unborn children

In many countries with high malaria rates, the problem is worsened by lack of access to preventive measures, medical care and information.

Immunity can wane

Residents of a malaria region may be exposed to the disease enough to acquire a partial immunity, which can lessen the severity of malaria symptoms. However, this partial immunity can disappear if you move to a place where you’re no longer frequently exposed to the parasite.

Complications

Malaria can be fatal, particularly when caused by the plasmodium species common in Africa. The World Health Organization estimates that about 94% of all malaria deaths occur in Africa — most commonly in children under the age of 5.

Malaria deaths are usually related to one or more serious complications, including:

• Cerebral malaria. If parasite-filled blood cells block small blood vessels to your brain (cerebral malaria), swelling of your brain or brain damage may occur. Cerebral malaria may cause seizures and coma.
• Breathing problems. Accumulated fluid in your lungs (pulmonary edema) can make it difficult to breathe.
• Organ failure. Malaria can damage the kidneys or liver or cause the spleen to rupture. Any of these conditions can be life-threatening.
• Anemia. Malaria may result in not having enough red blood cells for an adequate supply of oxygen to your body’s tissues (anemia).
• Low blood sugar. Severe forms of malaria can cause low blood sugar (hypoglycemia), as can quinine — a common medication used to combat malaria. Very low blood sugar can result in coma or death.

Malaria may recur

Some varieties of the malaria parasite, which typically cause milder forms of the disease, can persist for years and cause relapses.

Prevention

If you live in or are traveling to an area where malaria is common, take steps to avoid mosquito bites. Mosquitoes are most active between dusk and dawn. To protect yourself from mosquito bites, you should:

• Cover your skin. Wear pants and long-sleeved shirts. Tuck in your shirt, and tuck pant legs into socks.
• Apply insect repellent to skin. Use an insect repellent registered with the Environmental Protection Agency on any exposed skin. These include repellents that contain DEET, picaridin, IR3535, oil of lemon eucalyptus (OLE), para-menthane-3,8-diol (PMD) or 2-undecanone. Do not use a spray directly on your face. Do not use products with oil of lemon eucalyptus (OLE) or p-Menthane-3,8-diol (PMD) on children under age 3.
• Apply repellent to clothing. Sprays containing permethrin are safe to apply to clothing.
• Sleep under a net. Bed nets, particularly those treated with insecticides, such as permethrin, help prevent mosquito bites while you are sleeping.

Preventive medicine

If you’ll be traveling to a location where malaria is common, talk to your doctor a few months ahead of time about whether you should take drugs before, during and after your trip to help protect you from malaria parasites.

In general, the drugs taken to prevent malaria are the same drugs used to treat the disease. What drug you take depends on where and how long you are traveling and your own health.

Vaccine

The World Health Organization has recommended a malaria vaccine for use in children who live in countries with high numbers of malaria cases.

Researchers are continuing to develop and study malaria vaccines to prevent infection.

Malaria – Symptoms & causes

Overview

Malaria is a disease caused by a parasite. The parasite is spread to humans through the bites of infected mosquitoes. People who have malaria usually feel very sick with a high fever and shaking chills.

While the disease is uncommon in temperate climates, malaria is still common in tropical and subtropical countries. Each year nearly 290 million people are infected with malaria, and more than 400,000 people die of the disease.

To reduce malaria infections, world health programs distribute preventive drugs and insecticide-treated bed nets to protect people from mosquito bites. The World Health Organization has recommended a malaria vaccine for use in children who live in countries with high numbers of malaria cases.

Protective clothing, bed nets and insecticides can protect you while traveling. You also can take preventive medicine before, during and after a trip to a high-risk area. Many malaria parasites have developed resistance to common drugs used to treat the disease.

Products & Services

Symptoms

Signs and symptoms of malaria may include:

• Fever
• Chills
• General feeling of discomfort
• Headache
• Nausea and vomiting
• Diarrhea
• Abdominal pain
• Muscle or joint pain
• Fatigue
• Rapid breathing
• Rapid heart rate
• Cough

Some people who have malaria experience cycles of malaria “attacks. ” An attack usually starts with shivering and chills, followed by a high fever, followed by sweating and a return to normal temperature.

Malaria signs and symptoms typically begin within a few weeks after being bitten by an infected mosquito. However, some types of malaria parasites can lie dormant in your body for up to a year.

When to see a doctor

Talk to your doctor if you experience a fever while living in or after traveling to a high-risk malaria region. If you have severe symptoms, seek emergency medical attention.

Causes

Malaria is caused by a single-celled parasite of the genus plasmodium. The parasite is transmitted to humans most commonly through mosquito bites.

Mosquito transmission cycle

Malaria transmission cycle

Malaria spreads when a mosquito becomes infected with the disease after biting an infected person, and the infected mosquito then bites a noninfected person. The malaria parasites enter that person’s bloodstream and travel to the liver. When the parasites mature, they leave the liver and infect red blood cells.

• Uninfected mosquito. A mosquito becomes infected by feeding on a person who has malaria.
• Transmission of parasite. If this mosquito bites you in the future, it can transmit malaria parasites to you.
• In the liver. Once the parasites enter your body, they travel to your liver — where some types can lie dormant for as long as a year.
• Into the bloodstream. When the parasites mature, they leave the liver and infect your red blood cells. This is when people typically develop malaria symptoms.
• On to the next person. If an uninfected mosquito bites you at this point in the cycle, it will become infected with your malaria parasites and can spread them to the other people it bites.

Other modes of transmission

Because the parasites that cause malaria affect red blood cells, people can also catch malaria from exposure to infected blood, including:

• From mother to unborn child
• Through blood transfusions
• By sharing needles used to inject drugs

Risk factors

The greatest risk factor for developing malaria is to live in or to visit areas where the disease is common. These include the tropical and subtropical regions of:

• Sub-Saharan Africa
• South and Southeast Asia
• Pacific Islands
• Central America and northern South America

The degree of risk depends on local malaria control, seasonal changes in malaria rates and the precautions you take to prevent mosquito bites.

Risks of more-severe disease

People at increased risk of serious disease include:

• Young children and infants
• Older adults
• Travelers coming from areas with no malaria
• Pregnant women and their unborn children

In many countries with high malaria rates, the problem is worsened by lack of access to preventive measures, medical care and information.

Immunity can wane

Residents of a malaria region may be exposed to the disease enough to acquire a partial immunity, which can lessen the severity of malaria symptoms. However, this partial immunity can disappear if you move to a place where you’re no longer frequently exposed to the parasite.

Complications

Malaria can be fatal, particularly when caused by the plasmodium species common in Africa. The World Health Organization estimates that about 94% of all malaria deaths occur in Africa — most commonly in children under the age of 5.

Malaria deaths are usually related to one or more serious complications, including:

• Cerebral malaria. If parasite-filled blood cells block small blood vessels to your brain (cerebral malaria), swelling of your brain or brain damage may occur. Cerebral malaria may cause seizures and coma.
• Breathing problems. Accumulated fluid in your lungs (pulmonary edema) can make it difficult to breathe.
• Organ failure. Malaria can damage the kidneys or liver or cause the spleen to rupture. Any of these conditions can be life-threatening.
• Anemia. Malaria may result in not having enough red blood cells for an adequate supply of oxygen to your body’s tissues (anemia).
• Low blood sugar. Severe forms of malaria can cause low blood sugar (hypoglycemia), as can quinine — a common medication used to combat malaria. Very low blood sugar can result in coma or death.

Malaria may recur

Some varieties of the malaria parasite, which typically cause milder forms of the disease, can persist for years and cause relapses.

Prevention

If you live in or are traveling to an area where malaria is common, take steps to avoid mosquito bites. Mosquitoes are most active between dusk and dawn. To protect yourself from mosquito bites, you should:

• Cover your skin. Wear pants and long-sleeved shirts. Tuck in your shirt, and tuck pant legs into socks.
• Apply insect repellent to skin. Use an insect repellent registered with the Environmental Protection Agency on any exposed skin. These include repellents that contain DEET, picaridin, IR3535, oil of lemon eucalyptus (OLE), para-menthane-3,8-diol (PMD) or 2-undecanone. Do not use a spray directly on your face. Do not use products with oil of lemon eucalyptus (OLE) or p-Menthane-3,8-diol (PMD) on children under age 3.
• Apply repellent to clothing. Sprays containing permethrin are safe to apply to clothing.
• Sleep under a net. Bed nets, particularly those treated with insecticides, such as permethrin, help prevent mosquito bites while you are sleeping.

Preventive medicine

If you’ll be traveling to a location where malaria is common, talk to your doctor a few months ahead of time about whether you should take drugs before, during and after your trip to help protect you from malaria parasites.

In general, the drugs taken to prevent malaria are the same drugs used to treat the disease. What drug you take depends on where and how long you are traveling and your own health.

Vaccine

The World Health Organization has recommended a malaria vaccine for use in children who live in countries with high numbers of malaria cases.

Researchers are continuing to develop and study malaria vaccines to prevent infection.

Malaria: treatment, symptoms, diagnosis, classification

Malaria (also known as swamp fever) is a very dangerous infectious disease, the infection of which most often occurs through a mosquito bite. The disease is characterized by a high mortality rate, and therefore requires special attention.

Being extremely dangerous, this disease more than once influenced historical events – it caused the death of famous people (Dante, Columbus, Alexander the Great), was a determining factor in various wars, and led to the decline of entire countries.

Malaria is common in certain countries: Vietnam, Colombia, India, Sri Lanka, Brazil, parts of Africa. About 40% of the world’s population lives in the habitats of malaria mosquitoes. Every year, the disease claims more lives than tuberculosis and pneumonia.

Ways of transmission

The main route of transmission is the bite of a malarial mosquito (female). But there are other, more rare ways of infection:

• from infected mother to child;
• when transfused with blood from an infected person;
• when injected with a syringe previously used by the infected person.

The essence of the disease is that during a bite, parasites enter the liver through the blood – malarial plasmodia. They destroy red blood cells and continue to multiply, affecting more and more blood cells.

Symptoms

Symptoms of malaria appear at different intervals after infection: from 1 to 4 weeks. Signs of infection with malarial plasmodia include:

• fever;
• excessive sweating;
• weakness;
• headaches.

Often the initial signs are mild, but gradually they begin to intensify. One of the signs of the disease is a cyclical manifestation of symptoms: an exacerbation lasts for 6-10 hours, then a recession occurs. At this time (about 2-5 hours) a person often falls into a deep sleep. After another 2-3 days, the exacerbation is repeated.

Other signs of the disease also include:

• aching joints;
• enlarged liver, spleen;
• diarrhea;
• elevated body temperature;
• nausea and vomiting;
• anemia;
• great debility;
• problems in the work of the heart.

If you find the first signs, even rather weak ones, you should immediately seek medical help. Treatment of this disease at home is impossible and can lead to death of a person!

Complications

Malaria is dangerous because as a result of the action of parasites, many organs suffer. Possible complications:

• cerebral edema;
• acute renal failure;
• heart failure;
• serious infestation by parasites of various internal organs;
• malarial coma;
• mental disorders.

The development of the disease also depends on its type, which is determined by the type of pathogen.

Children under 5 years of age are the most susceptible to infection. About 67% of all deaths due to this disease are at their expense.

Species

There are four types of malaria:

• tropical. It is the most common and dangerous – more often than others it causes complications. More than 90% of cases are of this type;
• four days. It is named so for the reason that acute attacks of the disease most often occur after 72 hours;
• three-day. In this case, attacks will occur more often – on average after 40-48 hours;
• oval-malaria. The cycle of attacks is similar to the previous option.

It is important to understand that after illness and recovery, immunity to re-infection is not developed. Such immunity can be developed after a year or after several infections, however, even in this case it is not very effective, since it can only act on certain types of parasites and does not provide complete protection, but only reduces symptoms.

Disease statistics in Russia

The causative agents of this disease do not live in Russia and Moscow. All cases that are found among the inhabitants of the country are imported. They are not so common – 0.1 case per 100 thousand population. In recent years, no cases of local transmission of the disease have been detected in Moscow and other cities of the country. However, the malaria pathogen is still dangerous for those traveling to countries where it is prevalent.

Diagnostics

Diagnosis of malaria is based on symptoms and a blood test. If there are reasons to suspect infection, but the first analysis gives a negative result, the study is repeated after 4-6 hours – in this case, laboratory diagnostic methods give a more accurate result.

Treatment

Malaria is treated exclusively in a hospital under the supervision of doctors. The basis of programs in working with patients is the use of quinine. Other preparations are selected depending on the region in question. The fact is that parasites often develop resistance to certain substances – this also applies to antibiotics that are used for symptomatic treatment. Often, along with the general plan, the patient needs an individual approach in order to achieve the highest quality result.

Prevention

At the moment, there is no licensed vaccine that has proven itself in the fight against malaria, but some drugs are in the testing stage and are already showing themselves quite well.

Until a vaccine is introduced, malaria prophylaxis is:

• taking special antimalarial drugs. Reception begins 1-2 weeks before a trip to a country where this disease is relevant, lasts the entire period of stay in the outbreak or nearby, and also 4-6 weeks after the person has left the danger zone. Important: medicines (only a doctor can prescribe) do not protect against infection, but if this happens, they help to transfer the disease more easily. It is impossible to prescribe special drugs for yourself without a doctor – their combination is selected taking into account the region and the resistance of local parasites to various substances;
• detailed acquaintance with all the symptoms of malaria. It is important to know them so as not to miss the disease. Often the cause of deaths is precisely the fact that people seek help late, not understanding what they are dealing with;
• making a plan in case of illness. The key point is to find clinics or doctors who treat the disease in advance. And you should also make sure that there are drugs for treatment at the place – otherwise it is better to take them with you for a long stay;
• observe all safety measures: treat skin and clothes with special mosquito repellents, wear bright clothes, constantly inspect yourself and them. In residential areas, it is imperative to use mosquito nets and bed covers. It is important that the grids are not damaged.

The more careful a person is, the more strictly he follows the clinical recommendations for malaria, the higher the chance that he will not encounter the disease. And if this happens, he will have a much better chance of easily transferring the disease without serious complications.

Q&A on the topic

For whom is the disease most dangerous?

At risk are small children, pregnant women, as well as people with weakened immunity for various reasons. So, people with HIV and other types of immunodeficiencies are very difficult to tolerate this disease. They are more likely to develop complications from malaria.

Is there a cure for malaria?

This disease requires long-term and thorough treatment, but with timely access to a doctor and high-quality prevention, the patient recovers completely. However, the risks are still very high.

How to smear malaria?

It is unacceptable to use any means on your own without consulting a doctor. The disease is treated exclusively (!) Under the supervision of physicians, drugs are selected individually depending on the region in which the infection occurred.

Malaria: symptoms, pathogens, treatment, doctor’s advice

The article was commented and checked by Anna Tsygankova, Senior Consultant at the medical company BestDoctor

• What is malaria
• Exciters
• Varieties
• Symptoms
• Diagnostics
• Treatment
• Inoculation
• Prophylaxis
• Malaria in Russia
• Expert commentary

What is malaria

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Malaria is one of the most common infectious diseases in the world. It is caused by plasmodia parasites carried by malarial mosquitoes. The incubation period of the disease can last from 11 days to several months. The main symptom is regular bouts of severe fever that occur every two to three days. In severe forms, the disease can lead to dangerous organ damage.

Even 80 years ago, malaria was spread all over the globe. However, thanks to the development of the economy and medicine, today the disease has been defeated in half the countries of the world and is rampant only in hot developing countries. Scientists believe that humanity will be able to completely defeat malaria by 2050, although this will require spending an additional $2 billion a year to fight it [1].

According to WHO, about 228 million people fall ill with malaria each year, of which 400,000 die. 94% of malaria cases are reported in Africa, half of them in six countries: Nigeria, Congo, Tanzania, Burkina Faso, Mozambique and Niger. Children from six months to five years of age, who are completely immune to the disease, suffer the most from malaria. They account for two thirds of malaria deaths.

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Tourists and travelers are often infected with malaria. According to WHO, about 10,000 people annually bring the disease from foreign trips.

Malaria

The disease is carried by mosquitoes of the genus Anopheles, infected with malarial plasmodia, protozoan parasites, which are the direct causative agents of the disease. Malarial mosquitoes live mainly in swamps and in small stagnant water bodies, including puddles. Many countries have eradicated malaria through massive swamp draining campaigns.

Two hundred species of malarial mosquitoes can be found all over the planet, with the exception of deserts and territories of the Far North. In Russia, the species Anopheles Messeae is common. However, he stopped carrying the disease over 50 years ago. Today, malaria can only be contracted from Asian and African species of malarial mosquitoes.

First, the malarial mosquito drinks the blood of a person infected with malaria. Plasmodium enters his intestines. It then bites another person and transfers the parasite larvae to them. Those first enter the liver, where they grow and develop. When Plasmodium become adults, they pass from the liver into the bloodstream, after which the first symptoms of malaria appear in humans. Some varieties of Plasmodium can doze in the liver for a long time.

Malaria can also be transmitted from person to person without the involvement of mosquitoes: from mother to child (very rare), through blood transfusion, and by sharing injection needles.

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Types of malaria

Of the several hundred malarial Plasmodium, only five are dangerous to humans. Each one causes a different kind of disease.

Three-day malaria

Plasmodium vivax causes three-day malaria (vivax-malaria) – a relatively mild form with a long course. It is characterized by the fact that malarial attacks of fever occur every two days, often at the same time of the day, from 11 am to 4 pm. Another variety of the pathogen, P. ovale, causes ovale malaria, which is similar to three-day malaria.

P. Vivax is distributed in Tajikistan, Afghanistan, Pakistan and Nepal, as well as in Central America and northern South America. Previously, this particular type of plasmoid was common in Europe and Russia. P. ovale is found mainly in Africa, where the Plasmodium that causes dengue is found.

Four-day malaria

P. malariae causes four-day malaria, in which attacks occur every 70-72 hours. This form is not as severe, but in rare cases it can cause serious damage to the kidneys – nephrological syndrome. Plasmodium of this type can live hidden in the human body for decades even after recovery. They cause a fairly rare type of malaria found in India, Indonesia, Cambodia and Laos.

Tropical malaria

P. falciparum causes tropical malaria. This is the most dangerous type of the disease, and at the same time the most common – it accounts for more than 90% of infections. Attacks occur irregularly, and the disease affects the vessels, which can lead first to hypoxia, and then to organ failure. This type of illness dominates all of Africa, and in countries such as India, Vietnam, and Thailand, it occurs about as often as three-day malaria.

Malaria Knowlesi

The possibility of human infection with P. knowlesi was discovered only in 2004 – it was previously thought that it only infects macaques. This type of malaria develops the fastest and is therefore very dangerous if treatment is delayed [2]. The features of this type of malaria are still poorly understood, but researchers call this form no less severe than tropical [3]. This type of malaria is common in Southeast Asia, primarily in Malaysia, the Philippines and Indonesia.

Symptoms of malaria

Most often, the first symptoms of malaria appear 11-30 days after infection, although both types of Plasmodium that cause the three-day form can sleep in the liver for up to 15 months.

At the first stage of the disease, pathogens multiply and accumulate in the blood, and the symptoms resemble general poisoning – a person is shivering, nauseous, he experiences weakness, body aches and pain in the joints and limbs. Distinguishing malaria from other infectious diseases at this stage is very difficult.

When there are many Plasmodium in the blood, the peak of the disease sets in, which consists of recurring malarial attacks, or paroxysms. Depending on the type of disease, attacks occur every other day or every two to three days.

An attack lasts from 15 minutes to two hours. Symptoms resemble the flu: the temperature rises sharply to 39-41 °, the pressure drops, breathing quickens. A person is sick or vomits, he may become delirious. Then the temperature drops sharply, the patient feels severe weakness and quickly falls asleep. Rashes similar to herpes may appear on the lips. Waking up, a person feels healthy, but after a while the attack is repeated. When the patient begins to recover, the attacks become less severe and eventually disappear altogether.

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All patients with malaria have an enlarged liver and spleen by the fifth or seventh day of illness, and in addition develop anemia (anemia).

According to the clinical picture, malaria is divided into uncomplicated and severe, in which the disease causes not only attacks, but also damage to organs.

The main complications of malaria are:

Nephrotic syndrome

This is a dangerous, almost untreatable kidney disease that can occur with four days of malaria.

Cerebral malaria

Brain damage, which most often develops due to inadequate treatment. It begins with headache and mild impairment of consciousness, and if left untreated can lead to coma and death.

Algid malaria

Toxic shock, which occurs due to the huge content of parasites in the blood. It begins with symptoms of severe intoxication, can lead to coma and death.

Hemoglobinuric (blackwater) fever

An extremely serious complication of dengue fever, which most often occurs when treatment is started late. After taking drugs, there are too many dead plasmodia and dead red blood cells in the human blood at the same time, which die due to drugs. The most characteristic manifestations are vomiting of black bile and black urine. Some studies have associated this complication with quinine, a drug used to treat severe forms of malaria.

Tears and organ failure

Malaria can severely damage the kidneys, liver or spleen, the latter up to rupture.

Diagnosis of malaria

The vast majority of cases of malaria in Europeans are diagnosed after visiting tropical countries where the disease is present.

In its early stages, malaria develops in the same way as many other infectious diseases. The main method of accurate diagnosis is blood smear microscopy, which allows detecting parasites. Only after their identification, the doctor can make a final diagnosis.

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More rarely, less accurate methods of immunological diagnostics are used, in which specific antibodies or antigens of Plasmodium are searched for in the blood.

There are also rapid tests for parasite antigens, but they are not very accurate.

Treatment of malaria

In Russia and other non-endemic countries for malaria, it is treated only in a hospital.

To cure the disease, it is necessary to kill the plasmodia in the blood. For this, antiparasitic drugs are used.

The most common treatment for uncomplicated malaria today is combination therapy. Most often, it contains artemisinin or its derivatives – this is an antiparasitic drug that is made from wormwood (artemisia). It is effective against all types of malarial plasmodia, but treatment with it alone often leads to relapse. Therefore, artemisinin is supplemented with other, more specific antimalarial drugs. In addition, if mass treatment of malaria with only artemisinin, Plasmodium will inevitably develop resistance to it over time, and humanity will be almost defenseless against the disease. In Russia, drugs based on artemisinin are not registered. Malaria ovale is treated with a combination of primaquine and chloroquine.

Main drugs used in the treatment of malaria:

• chloroquine;
• hydroxychloroquine;
• primaquine;
• quinine;
• mefloquine;
• artemisinin;
• artesunate;
• artemether;
• arteeter;
• proguanil;
• tetracycline;
• doxycycline.

The choice of remedy depends on the form of malaria and also on the region in which the infection occurred [4]. For example, the malarial plasmodia of Afghanistan and Pakistan have developed resistance to chloroquine, while the Thai and Myanmar parasites have also developed resistance to mefloquine [5].

In the treatment of malaria with complications, antimalarial drugs are supplemented with specific drugs for the affected organs.

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Malaria vaccine and malaria immunity

The only working malaria vaccine, RTS,S, was created in the late 1980s, but only received EU approval in 2015. It has a rather low efficiency – RTS,S provides 27% protection against all forms of malaria and 58% from severe ones [6]. Today, it is being vaccinated in children in countries where malaria is most common, and is not available to travelers and residents of developed countries.

People living in countries where malaria is present may have an innate immunity to it. West African and African American populations have the Duffy gene, which makes them immune to infection with three-day malaria. Other genetic factors may make them more resistant to tropical malaria as well. Also, the risk of getting malaria is lower in people suffering from sickle cell anemia, a rare genetic disease that also occurs mainly in blacks [7].

After an illness, a person develops unstable acquired immunity, which grows stronger with each re-infection. In an immunocompetent patient, malaria can be almost insidious, with very low levels of parasites in the blood. In societies where people are constantly exposed to malaria and are infected with it several times a year, many develop strong immunity to the disease by the age of puberty [8].

Malaria prevention

Prevention of malaria is basically protection against mosquito bites. WHO recommends wearing full-body clothing and using insect repellents on the skin and living quarters. Of the repellents, it is best to use products that contain DEET, IR3535 or icaridin. International organizations distribute mosquito nets impregnated with mosquito repellents in countries with malaria – they are considered one of the most convenient, simple and effective ways to protect against the disease [9].

There is also a group of antimalarial drugs that are effective in preventing the disease. Doctors advise taking antimalarial drugs before traveling to a malarial country, as well as during travel and for some time after it. In Russia, mefloquine and chloroquine are most often prescribed. Only a doctor can choose the right drug.

Rospotrebnadzor recommends that tourists returning from countries with malaria monitor their temperature for three years after their trip.

Malaria in Russia

From prehistoric times to the middle of the 20th century, malaria was widespread throughout the world (except for the Far North), including most of Russia.

In Rus’, the disease was called “shaking”, “pale” or “death”. In the mid-1930s, a large-scale malaria epidemic swept through the Soviet Union, which affected the Volga region, the Urals and Ukraine. However, industrialization, the drainage of swamps and the development of medicine gradually helped to cope with malaria. At 19In 1962, the authorities announced that the disease was completely defeated.

After the collapse of the Soviet Union, the disease returned to Central Asia. In the 2000s, most of the infections imported into Russia were associated with migrants from Tajikistan, Azerbaijan and Uzbekistan. However, the situation there quickly improved – today the only post-Soviet state where endemic malaria is present is Tajikistan, but it is also close to completely defeating the disease [10].

For the last decade, 80-120 cases of malaria have been registered in Russia per year. All of them are imported, most often from Africa, as well as from India, Thailand, Latin America and the countries of the Middle East [11].

In 2020, Tanzania became the main supplier of malaria to Russia, one of the few countries that did not close the borders to tourists. According to the head of Rospotrebnadzor Anna Popova, 11 cases of malaria were imported from there. Two patients are known to have died.

Expert comments

Anna Tsygankova, Senior Consultant, BestDoctor Medical Company

How toxic are malaria drugs? What side effects can they have?

Side effects may occur with all medicines. In the case of malaria chemoprophylaxis, drugs are used that are supposed to kill the parasite, and they are quite toxic. However, there is a concept of risk-benefit, that is, chemoprophylaxis for a European is potentially much less harmful than malaria. All registered prophylactic drugs have undergone post-marketing studies and have proven their effectiveness and safety. Mild nausea, occasional vomiting, and frequent loose stools should not lead to discontinuation of prophylaxis, but if these symptoms persist, medical advice should be sought. A rare complication (1 in 10,000 travelers) has been described when taking mefloquine: the development of neurological symptoms, seizures, and psychosis.

Can the complications of malaria lead to fatal organ dysfunction, disability or disability?

If you seek medical help and start treatment in time, then malaria disappears completely. Severe forms of the disease are individual, in some cases they lead to death.