Malaria is a serious tropical disease transmitted by mosquitoes, even one bite from an infected mosquito is enough to be infected. If not diagnosed and treated promptly, malaria can be deadly.
The most common disorders (symptoms) with which it can occur are:
- sweating and chills
- He retched
- muscle aches
They usually appear between 7 and 18 days after the infection but, in some cases, they may not appear for more than a year or sometimes even longer. If after a trip to countries where malaria is present, symptoms similar to those described should occur, it is necessary to consult a doctor immediately, even long after the trip to the endemic area.
A blood test is sufficient to ascertain (diagnose) the disease. Generally, the result is provided the same day so that appropriate therapy can be started immediately if the presence of the infection is confirmed.
Malaria is caused by such a parasitic protozoan Plasmodium. There are several species but only five cause disease in humans. The Plasmodium in most cases it is spread by female mosquitoes of species belonging to the genus Anopheles which mainly sting at dusk and during the night. When an infected mosquito bites a human, it transfers the parasites into their blood. Although rarely, malaria can also be transmitted through blood transfusions, organ transplantation, and the sharing of blood-contaminated needles or syringes.
The disease is present in more than 100 countries around the world, mainly in tropical regions including:
- large areas of Africa and Asia
- Central and South America
- Haiti and the Dominican Republic
- some parts of the Middle East
- some islands in the Pacific
Malaria is no longer present in Italy since the "early 1960s" but it is the main imported disease in our country. An average of 700 imported cases of malaria are registered in Italy every year, over 90% of which come from Sub-Saharan Africa.
According to the latest estimate contained in the World Malaria Report 2019, published by the World Health Organization (WHO), in 2018 there were 228 million cases of malaria and 405,000 deaths (227,000 in children under of 5 years of age).
Many cases of malaria can be avoided with simple precautions:
- risk awareness, verifying if malaria is present in the country you are going to visit
- prevention of exposure to mosquito bites, through the use of insect repellents to be applied to the uncovered parts of the body and mosquito nets treated with insecticides
- verification of the need to take anti-malaria drugs, by consulting the attending physician or an authorized center of the regional health service to find out if it is appropriate to start antimalarial prophylaxis before traveling to countries at risk of infection. If therapy is necessary, it is advisable to respect the medical prescription on doses and duration
- diagnosis, consulting a doctor immediately if symptoms of malaria occur upon return from the trip
The antimalarial drug is used to both prevent and treat malaria. The choice of the type of medicine and the duration of treatment will depend on:
- type of malaria
- the severity of symptoms
- geographic area in which you are infected
- use of an antimalarial drug for preventive purposes (prophylaxis)
- state of pregnancy
In some cases, your doctor may recommend that you take comprehensive treatment (so-called emergency treatment) for malaria with you on your trip. Typically, this happens when there is a risk of becoming infected while traveling in a remote area with little or no access to medical care.
Malaria is a serious disease that can get worse very quickly. It can be fatal if not treated promptly and can cause serious complications, including:
- severe anemia, occurs when red blood cells are unable to carry enough oxygen to the body's tissues. It causes drowsiness and weakness
- cerebral malaria, consists in the obstruction of the small blood vessels that carry blood to the brain. It is rare and occurs with seizures, brain damage and coma
The effects of malaria are usually more severe in pregnant women, infants, young children and the elderly. Pregnant women are usually not advised to travel to areas at risk for malaria.
Disorders (symptoms) caused by malaria can develop rapidly and usually occur within seven days of being bitten by an infected mosquito.
The time that passes between infection and the onset of disorders (incubation period) varies, on average, between 7 and 18 days, depending on the type of parasite. However, in some cases, it can last up to a year.
The initial symptoms of malaria are flu-like and include:
- He retched
They are often mild and can be difficult to associate with the disease.
In some types of malaria, fever occurs in 48-hour cycles that begin with the onset of chills, followed by fever, accompanied by sweating and great fatigue. These complaints (symptoms) usually last between 6 and 12 hours.
They can also occur:
- muscle aches
- general malaise
The most severe type of malaria is caused by the parasite species known as Plasmodium falciparum. Without prompt treatment it could cause serious and life-threatening complications such as breathing problems and failure of vital organs to function.
When to seek medical attention
If, upon returning from a trip to countries where the disease is present, the described disorders appear, it is necessary to immediately contact the treating doctor who, after having evaluated them, if he deems it necessary, may prescribe a blood test to ascertain, or not, the presence of infection. If the result is positive, treatment should be started immediately. Sometimes, the signs of the disease can appear even a year after the infection. It is therefore advisable to never underestimate ailments that can be referred to malaria.
Malaria is caused by the bite of infected mosquitoes which transfer the parasite known as plasmodium. There are several species but only five of them cause malaria in humans:
- plasmodium falciparum, prevalent mainly in Africa, is the most common type of malarial parasite and is responsible for most of the deaths worldwide
- plasmodium vivax, mainly present in Asia and South America, causes milder complaints (symptoms) than plasmodium falciparum and can remain "dormant" in the liver for up to three years. During this period, it can reactivate and cause relapses of the disease
- plasmodium ovale, quite unknown and usually present in West Africa, can remain in the liver for several years without causing disturbances
- plasmodium malariae, quite rare, usually found only in Africa
- plasmodium knowlesi, very rare it is widespread in some parts of Southeast Asia
How malaria is transmitted
The plasmodium it is transmitted by female mosquitoes belonging to the family anopheles. They bite between dusk and dawn. The mosquito can become infected by biting a person already suffering from malaria and then can transmit the parasite by biting other people. However, malaria cannot be transmitted directly from individual to individual.
After the bite of the infected mosquito, the parasite enters the bloodstream and reaches the liver, where it develops before reentering the blood and invading the red blood cells. The parasites grow and multiply inside them, then, at regular intervals, the infected red blood cells rupture, releasing the parasites into the blood. This generally occurs every 48-72 hours, depending on the species of plasmodium, each time causing a bout of fever, chills and sweating.
Malaria can also be spread through blood transfusions and needle sharing, but these routes of transmission are very rare.
Prevention and Therapy
Antimalarial drugs are used both to prevent (prophylaxis) and to treat malaria.
Generally, if you plan a trip to areas where the risk of getting sick is always present (so-called areas endemic), it is strongly advisable to use antimalarial prophylaxis, a prevention tool with documented efficacy. Before leaving, it is advisable to inquire at regional specialist centers on the behaviors to be followed in countries where malaria is present.
In any case, it is very important to always take the dose of the drug prescribed by the doctor and continue the treatment according to his instructions. Preventive antimalarial therapy can reduce the risk of infection by about 90% but does not completely eliminate it. It is therefore advisable to take the necessary measures to avoid or minimize mosquito bites (entomoprophylaxis).
The choice of treatment to be used can be made based on the following criteria:
- place of destination
- health state (anamnesis)
- any allergies to the drug
- possible use of other medicines
- problems encountered with antimalarial drugs in the past
It may be necessary, before leaving, to carry out a short test treatment with antimalarial drugs to check that no adverse reactions or undesirable effects (side effects) occur. If they do occur, other drugs can be chosen as an alternative.
Types of antimalarial drugs
The main types of malaria drugs used for disease prevention include:
- atovaquone / proguanil association
- dosage, the adult dose is one tablet per day. In children, the amount of the drug depends on the weight. Treatment should be started one or two days before the start of the trip, continued for the period of stay in a malarial area and for seven days after the return
- recommendations, the antimalarial drug should not be taken by pregnant or breastfeeding women. It is also not recommended for people with severe kidney problems
- possible side effects: stomach pain, headache, rash and mouth ulcers
- other factors, it can be more expensive than other antimalarial drugs
- doxycycline (also known as vibramycin-D)
- dosage, the adult dose is 100 mg per day in the form of a tablet or capsule. Treatment must be started two days before departure, continued daily while staying in a risk zone, and for four weeks after returning
- recommendations, it is not suitable for:
- women who are pregnant or breastfeeding
- children under the age of 12 (due to the risk of permanent tooth loss)
- people sensitive to named antibiotics tetracyclines or with liver problems
- possible side effects: stomach discomfort, heartburn, candidiasis, skin burns due to increased sensitivity to sunlight.It should always be taken with food, preferably standing or sitting
- other factors, it is relatively cheap. If you take doxycycline for acne, it will also provide protection against malaria at least as long as you take an adequate dose. The family doctor can provide more information
- dosage, the administration for the adult is equal to one tablet every seven days. Also in the child it should be used once a week, but the dosage will depend on the body weight. Treatment should be started three weeks before leaving for travel, continued while in a malaria-prone area, and for four weeks after returning.
- recommendations, it is not recommended in case of:
- depression or other mental health problems
- close family members with any of the diseases mentioned above
- severe heart or liver problems
- possible side effects: dizziness, headache, sleep disturbances (insomnia and vivid dreams) and psychiatric reactions (anxiety, depression, panic attacks and hallucinations). It is very important to tell your doctor about any mental health problems, including mild depression. Do not take this drug if you have epilepsy
- other factors, if you have never used mefloquine, it is advisable to test for three weeks before traveling to see if any side effects develop
- chloroquine + proguanil. The combination of antimalarial drugs, called chloroquine and proguanil, although nowadays it is rarely recommended because it is largely ineffective against the most common and dangerous type of malarial parasite: the Plasmodium falciparum. However, it may occasionally be recommended for certain destinations where the plasmodium falciparum it is less common than other types of malaria, such as India and Pakistan
If malaria is diagnosed and treated promptly, it can be cured completely. Therapy should be started as soon as tests confirm the presence of the parasite in the blood.
Many of the drugs shown to prevent malaria (prophylaxis) can also be used to treat it. However, when using an antimalarial medicine to prevent disease it should not be used to treat an attack. This means that it is important to tell your doctor about the medication you are taking for prevention.
The type of medicine and the duration of treatment will depend on:
- type of malaria which caused the infection
- area in which the infection occurred
- severity symptoms
- use of an antimalarial drug for preventive purposes
- possible state of pregnancy
In case of therapeutic failure due to the resistance of the parasite to the drug or combination of drugs used, the doctor will have to prescribe a different therapeutic protocol to fight the resistant parasites.
Antimalarial medicines are usually used in the form of tablets or capsules. In severe cases, they are administered intravenously in the hospital through a drip.
Currently, the best treatment available, particularly for malaria from Plasmodium falciparium, is represented by the combined therapy based on artemisinin derivatives (ACT).
The use of the dihydroartemisinin / piperaquine combination is today the therapeutic protocol of choice for the treatment of uncomplicated malaria in Italian hospitals.
In some cases, the doctor may prescribe a complete cure for malaria (the so-called emergency treatment) suggesting that you take it with you if you are traveling to a distant area, with little or no access to medical care, where there is a risk of getting sick.
Examples of drugs to use in this case include:
- atovaquone / proguanil
- artemether / lumefantrine
- dihydroartemisinin / piperaquine
Before prescribing emergency care, the family doctor may consult with a travel medicine specialist.
While taking antimalarial drugs:
- make sure you have the right antimalarial medication before you leave and, if in doubt, check with your doctor or pharmacist
- follow the instructions carefully supplied with the drug
- depending on the type of drug used, you need to continue taking it for up to four weeks after returning from travel to cover the incubation period of the disease
- inform the attending physician of any ongoing or chronic illnesses, so that they can prescribe the most suitable antimalarial drug for their case. You may be more at risk of unwanted effects (side effects) if you have:
- seropositivity from HIV or AIDS
- epilepsy or any type of seizure disorder
- depression or other mental health condition
- heart, liver or kidney problems
- use of drugs such as warfarin, to prevent blood clots
- combined hormonal contraception, such as the contraceptive pill or patches
If antimalarial drugs have already been used in the past, they are not necessarily suitable for the countries you will travel to in the future. The most suitable antimalarial, in fact, depends on the type of parasite transmitted by mosquitoes and its resistance to certain types of drugs. For this reason, it is always advisable to consult your family doctor or a travel medicine center before using them.
Malaria and antimalarials in pregnancy
The World Health Organization (WHO) recommends that pregnant women avoid traveling to areas where malaria is present as there is an increased risk of having a severe form and both the baby and the mother could develop serious complications such as, for example:
- birth before the 37th week of pregnancy (premature birth)
- low birth weight
- limited growth of the baby in the womb
- death of the mother
If it is not possible to postpone, or cancel, a trip to an area at risk for the presence of malaria, it is very important to consult your doctor and take a suitable antimalarial drug. Not all, in fact, are suitable for pregnant women and could cause unwanted effects (side effects) both in the mother and in the fetus.
Here are the safe and least expensive medications to use, or avoid, during pregnancy:
- mefloquine, it is not normally prescribed during the first trimester. If you think you are pregnant and are using the drug as a preventative (prophylaxis), you will need to stop it for three months. This is a precaution as there is no evidence to suggest a harmful effect of mefloquine on the fetus.
- doxycycline, has never been prescribed for pregnant or breastfeeding women, as it may harm the fetus
- combination of atovaquone and proguanil, is generally not indicated during pregnancy, or while breastfeeding, because research on its effects is still limited. However, if the risk of malaria is high, it can be recommended where there is no "suitable alternative."
- chloroquine combined with proguanil, is suitable during pregnancy but is rarely used because it is not very effective against the most common and dangerous type of parasite that causes malaria
- antimalarial vaccine. After more than 30 years of intense research, in 2016 the first malaria vaccine was finally developed, the RTS, S / AS01, which showed partial protection against malaria by Plasmodium falciparium in children.In April 2019 a pilot vaccination program, coordinated by the WHO, was launched for the gradual introduction of the RTS vaccine, S / AS01 in the routine vaccination program of three countries of sub-Saharan Africa: Malawi, Ghana and Kenya. a pilot study, which plans to vaccinate up to 360,000 children per year in the three countries, will address various still open questions, such as evaluating the effectiveness of the vaccine in real contexts; understand the best way to deliver the four required doses; the potential role of the vaccine in reducing infant deaths; its safety in routine use
Malaria is a serious disease that can worsen very quickly and, if not treated promptly, can be fatal or can cause serious complications, including:
- severe anemia, occurs when red blood cells are unable to carry enough oxygen to the body's tissues, causing drowsiness and weakness
- cerebral malaria, is rare and consists in the obstruction of the small blood vessels that carry blood to the brain and causes convulsions, brain damage and coma
The effects of malaria are usually more severe in pregnant women, infants, young children and the elderly. For this reason, pregnant women are generally not advised to travel to areas at risk for this disease.
The most severe disorders (symptoms), and most deaths from malaria, are caused by the parasite plasmodium falciparum. When the first ailments that lead to suspicion of infection appear, it is advisable to go to the doctor immediately to start treatment as soon as possible.
The destruction of red blood cells by the parasite that causes malaria can cause severe anemia and, consequently, the lack of a sufficient amount of oxygen in the organs and muscles of the body with the onset of drowsiness, fatigue and weakness.
In rare cases, malaria can affect the brain causing it to swell (brain edema) and causing fits of seizures, coma and even permanent damage. This form is known as cerebral malaria.
A severe form of malaria can cause other complications as well which include:
- liver failure and yellowing (jaundice) of the skin and the transparent membrane that covers the front of the eye and the inner part of the eyelids (conjunctiva)
- shock, a sudden drop in blood pressure
- pulmonary edema, a buildup of fluid in the lungs
- acute respiratory disorder syndrome (ARDS)
- too low blood glucose (hypoglycemia)
- kidney failure
- swelling and rupture of the spleen
It prevents malaria
Malaria is a preventable disease through simple precautions that aim to avoid contagion:
- be aware of the risk and check if malaria is present in the country where you are going to stay. Even if you were raised in a country where malaria is common, you need to take precautions to protect yourself from infection. No one, in fact, has complete and lasting immunity against malaria, and any level of natural protection a person has is. quickly lost when moving away from the hazard zone
- avoid exposure to mosquito bites infected by using an insect repellent, on exposed areas of the body, to be applied frequently. The most effective repellents contain diethyltoluamide (DEET) and are available in sprays, sticks and creams. They should be used carefully following the directions on the package but are not indicated in children under two months of age. Wear long-sleeved shirts and long pants, especially at dusk and at night when mosquitoes bite.If the room in which you stay does not have air conditioning that allows you to keep the windows closed, use a mosquito net treated with insecticides to be applied to the windows, doors and / or around the bed
- inquire at an authorized center of the regional health service on the need, or not, to take drugs for the prevention of malaria to travel to the chosen country. In case of a positive response, it is important to take the prescribed drug respecting the doses and duration of treatment indicated by the doctor
- diagnosis, consult a doctor immediately if symptoms attributable to malaria appear upon returning from the trip to an endemic area
NHS. Malaria (English)