Malaria

Malaria is one of the most significant infectious diseases. The cause is a single-cell parasite known as plasmodium, which is transmitted by the Anopheles mosquito.

Malaria is found in almost all tropical and subtropical regions, meaning in very warm regions near the equator, as well as in the warm temperate zones between approximately 25- and 40-degree northern and southern latitudes. The disease is found in approximately 100 countries and on all continents except for Australia.

The different types of malaria progress at different levels of severity, whereby each variation is caused by its own plasmodium type. Malaria tropica is the most dangerous type of malaria. If left untreated, it almost always leads to death in European travelers. Therefore, the malaria prophylaxis (preventative prophylactic measures) is particularly important prior to a visit in a risk region for malaria.

Malaria starts with symptoms such as fever, headaches, aching limbs, diarrhea, and a general feeling of illness. Often, these symptoms are misinterpreted as the flu or a gastrointestinal infection.

The symptoms of these various types of malaria differ mainly in how the fever progresses over time.

Malaria tropica

The amount of time from infection to the onset of symptoms (incubation period) for malaria tropica is typically 7 to 28 days, and in rare cases, up to approx. 120 days. In immigrants from regions at risk, who were often infected by malaria during their childhood and therefore have acquired partial immunity, malaria tropica can appear even years after initial infection.

Approximately three-fourths of malaria cases in Germany are malaria tropica. It is the most dangerous form of malaria and almost always leads to death in those who are not immune. Travelers from Germany are typically not immune from an acute form of malaria. The fever that occurs does not follow the fever pattern of other types of malaria.

Malaria tertiana

Malaria tertiana is rather mild and harmless. A typical symptom is a cyclic fever that spikes and then goes back down, appearing every third day. This is the reason it is called “tertiana”.

Malaria quartana

Malaria quartana is less common than other types of malaria. With this type of malaria, the fever appears every 4 days. “Quartana” basically means 4-day ague.

Knowlesi malaria

This type of malaria is found only in Southeast Asia. Knowlesi malaria can be just as acute as malaria tropica.

Malaria is caused by a single-cell parasite of the plasmodia genus. Various plasmodia types are responsible for the forms of malaria. The single-cell parasite is transmitted through the bite of the female Anopheles mosquito. The pathogen of malaria tertiana settles in the liver and can lie dormant for months or years, before an outbreak of the illness with symptoms occurs.

Transmission from person to person is only possible through blood and occurs very seldom.

Generally speaking, travelers from countries like Germany in which Malaria only exists as a disease brought back from travels belong to the at-risk group. These people are typically not immune to acute forms of malaria.

Pregnant women

Pregnant women should not travel to regions with malaria, because administering a malaria prophylaxis (medical prophylaxis) is very difficult during pregnancy. There is no certainty that taking medication will not affect the development of the child. Malaria during pregnancy puts the mother and child at risk in various ways.

Children

Approximately two-thirds of malaria deaths worldwide are children under the age of 5 living in the endemic disease regions.

Malaria is very common in certain risk regions; in Germany, the illness appears only in those who have returned from travels, generally speaking.

Malaria worldwide

Malaria is one of the most significant infectious diseases worldwide. It is found in tropical and subtropical regions on all continents, except for Australia – in approx. 100 countries. Around 40 percent of the world’s population lives in a malaria-endemic region. These are regions in which malaria is found continuously and frequently. In endemic regions, approximately 220 million people each year become ill.

Approximately 400,000 people die each year of malaria worldwide; about two-thirds of them are children under the age of 5. Malaria is found in over 90 percent of countries in Africa; malaria cases in Asia and South America have declined significantly in recent years. In the last few years, individual cases of malaria tertiana have been found in southern Europe, such as Spain and Greece.

Germany

Patients from Germany typically become infected when visiting a region at risk. In recent years, approximately 800 to 1,000 cases of malaria have been recorded in this country. Boys and men were infected twice as often as girls and women. Often, cases of malaria appear in immigrants who live in Germany and return to the country of their birth for vacation, for example.

Most cases of malaria are brought in from African countries. A significant number of cases appear after traveling to West African countries and Kenya. India and Pakistan are the most notable countries with infections outside of Africa.

“Airport malaria”

An extremely rare form of malaria found outside of the region where it is spread is known as airport malaria. It is transmitted by imported mosquitoes, either in an airplane, at an airport, or in their immediate surroundings. Baggage malaria is when mosquitoes are imported in the suitcase of an airplane passenger.

The various types of malaria progress in very different ways.

Progression depends mainly on:

• if the patient has already had malaria once or more than once and was able to build up a certain amount of immunity.
• the type of malaria.

Malaria tropica

Malaria tropica is by far the most dangerous form of malaria. Common initial symptoms are lassitude, headaches and aching limbs, as well as irregular feverish temperatures. Diarrhea is also a common symptom.

Numerous complications can arise:

• infection of the brain (cerebral malaria): typical symptoms are seizures and clouding of consciousness or even a coma
• acute kidney failure
• damage to the lungs
• enlargement of the spleen (approx. 26 percent)
• enlargement of the liver (approx. 14 percent)
• circulatory collapse
• red blood cell deficiency
• blood clotting in the blood vessels followed by internal bleeding

Malaria tertiana

Malaria tertiana is rather mild. A typical symptom is a cyclic fever that spikes and then goes down, appearing every third day. The person experiences chills, during which the fever spikes quickly to 40°C. After 3 or 4 hours of fever, the body’s temperature falls abruptly to a normal temperature but with profuse sweating.

Malaria quartana

Malaria quartana is less common than the other types of malaria. A typical symptom is a fever that occurs every 4 days. Relapses can occur up to 40 years after the initial infection.

Knowlesi malaria

Typical symptoms are bouts of fever. Knowlesi malaria can also be acute, similar to malaria tropica.

Since there is no vaccination for malaria, other types of preventative measures are very important. Those who plan to spend time in a region with malaria must speak with a doctor about the necessary preventative measures (individual prophylaxis) before leaving. They include protection from mosquitoes and medication (chemoprophylaxis).

Mosquito repellent

The Anopheles mosquito is active a dusk. The following protective measures are recommended for those traveling to a region with malaria:

• Stay in rooms that keep mosquitoes out and have air conditioning and insect screens whenever possible.
• Sleep under a mosquito net, preferably one that has been treated with substances to kill insects if possible.
• When outside, wear clothing that has also been treated with substances that kill insects: long-sleeve shirts, long pants, and socks that are light in color. Dark colors attract mosquitoes.
• Use anti-mosquito spray and creme.

Medication prophylaxis (chemoprophylaxis)

Speak to a doctor about which medication is most suitable. Medication is typically taken shortly before departure; it must be taken throughout the stay in the region with malaria and after returning home.

The following generally applies:

• A chemoprophylaxis is generally recommended for trips to countries with a high transmission potential.
• A chemoprophylaxis is generally not needed for trips to countries with a low or medium risk of malaria. It can be helpful to take along medication for self-treatment in an emergency.

If a chemoprophylaxis is not taken, a provisional medication should be packed for the trip. It can be taken if malaria-like symptoms appear and it is not possible to see a doctor. However, this is only an emergency measure until a doctor can be reached. Whether and which provisional medication should be brought along must be discussed with a doctor when planning the trip.

Details about selecting a medication and doses for adults and children can be found in the electronic document: Malariaprophylaxe – Empfehlungen des Ständigen Ausschusses Reisemedizin (StAR) der Deutschen Gesellschaft für Tropenmedizin und Internationale Gesundheit e.V. – DTG (Antimalarial Prophylaxis – Recommendations of the Standing Committee for Travel Medicine of the German Society for Tropical Medicine and Global Health).

If malaria is suspected, diagnostic tests must be started immediately to determine if the blood contains plasmodia. The type of plasmodia should be determined as early on as possible to

• determine the type of malaria, and
• make decisions about the next steps in treatment.

A blood sample is needed for diagnosis. The parasites causing the infection are identified using a microscope that examines the blood. This requires a lot of expertise, which means a medical specialist or tropical medicine institute must be consulted.

A list of tropical medicine institutions in Germany can be found on the German Society for Tropical Medicine and Global Health (Deutsche Gesellschaft für Tropenmedizin und Globale Gesundheit e.V.) website.

The type of malaria a person has determines how it is treated. Treatment for malaria tropica should be done at a hospital, and if possible, at one with tropical medicine experience and an intensive care ward.

Malaria tropica and Knowlesi malaria

Treatment depends on

• the level of severity of the infection, and
• any antimalarial prophylaxis that may have been taken prior to infection.

If the case of malaria tropica or Knowlesi malaria in question is uncomplicated and the patient has no life-threatening symptoms, medication with two compatible active ingredients is used to treat the patient.

If the case of malaria tropica or Knowlesi malaria is complicated and life-threatening symptoms are present, such as clouding of consciousness or difficulty breathing, the patient must be treated in an intensive care ward.

Malaria tertiana

Malaria tertiana is mainly treated with the same medication used for malaria tropica. To prevent a relapse, a second medication must be taken after the initial treatment. 

Malaria quartana

The medication chloroquine is used to treat this type of malaria.