Malaria in South Africa

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QUESTION

What are the high, low and no-risk areas for malaria in South Africa?

ANSWER

Malaria has been successfully controlled in many parts of South Africa, with the result that most of the country is not at risk for malaria transmission. However, some pockets of higher risk remain in the north-eastern corner of South Africa (north-eastern KwaZulu-Natal, with the southern-most limit of transmission corresponding with the Tugela River, Limpopo (Northern) Province, and Mpumalanga Province). Malaria is also transmitted in Kruger National Park.

Malaria in Myanmar (Burma)

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QUESTION

Is Malaria an issue in Myanmar where I am going in June?

ANSWER from Malaria.com Editor

YES. Malaria is a risk in all rural areas of the country below 1,000 meters of altitude (anything below 3300 feet). Rangoon/Yangon and Mandalay do not have malaria.

You should take medication to prevent malaria (prophylaxis) throughout your stay, and also protect yourself from getting bitten by mosquitoes if you are travelling to risk areas for malaria. Personal protection measures including sleeping under an insecticide treated bednet, wearing insect repellent and wearing long-sleeved clothing, especially in the evenings, early morning and throughout the night, which is when the mosquitoes that transmit malaria are active and feeding.

Myanmar/Burma is known to have strains of malaria which are resistant to certain medications; specifically, chloroquine resistance is widespread, while some areas in addition have malaria which is resistant to mefloquine (sold as Lariam). As such, the CDC recommends atovaquone-proguanil (sold as Malarone) or doxycycline if you will be travelling in the provinces of Bago, Kachin, Kayah, Kayin, Shan, and Tanintharyi. In all other areas of the country, mefloquine should also be considered as an option.

Answer from Malaria.com medical advisor

For anyone planning a trip abroad its important to know the health risks in your destination. Malaria is an especially important concern for anyone traveling to tropical or subtropical regions. Here’s what I found on the CDC Travelers’ Health website. I find this is the best place to look for this information.

  • Areas of Burma with Malaria: Rural areas throughout the country at altitudes
  • If you will be visiting an area of Burma with malaria, you will need to discuss with your doctor the best ways for you to avoid getting sick with malaria. Ways to prevent malaria include the following:
  • Taking a prescription antimalarial drug.
  • Using insect repellent and wearing long pants and sleeves to prevent mosquito bites. Sleeping in air-conditioned or well-screened rooms or using bednets.
  • Some areas of Burma have resistance to certain antimalarial drugs.

See the malaria information for Burma to find out which antimalarial drug is appropriate for the area you plan to visit in Burma.

Vaccine for malaria? Differences with yellow fever?

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QUESTION

Is there a vaccine to prevent malaria?
What is the difference between yellow fever and malaria?

ANSWER

In answer to your first question, no, there is not currently a vaccine available to prevent malaria. The best current candidate, the RTS,S vaccine which was developed by GlaxoSmithKline, is currently undergoing Phase III clinical trials in Africa. Although preliminary results showed up to a 50% rate of protection against malaria in some age groups, the trials will not conclude until 2014 and so full results will not be known until after that date.

As for your second question, while yellow fever and malaria are both transmitted by mosquitoes, they share few other similarities. Yellow fever is caused by a virus, for example, whereas malaria is caused by a single-celled parasite of the genus Plasmodium. The group of organisms that Plasmodium belongs to is often called “Protista” (the exact grouping and classification constantly changes!), and they more generally belong, based on cell type, to the Eukaryotes, an enormous group of organisms which also includes all mammals and even humans! Viruses, on the other hand, are tiny pieces of genetic material wrapped in a protein coating, and can hardly be described as alive in a conventional sense.

While both yellow fever and malaria are transmitted by mosquitoes, yellow fever is transmitted by the genus Aedes, whereas malaria is exclusively transmitted by the genus Anopheles (at least in humans, and all other mammals for that matter).While spraying inside households may reduce the prevalence of  both types of mosquitoes, Aedes mosquitoes tend to feed during the day, so sleeping under an insecticide-treated bednet is less protective against yellow fever than it is against malaria. Also, a vaccine is available for yellow fever (and has been available for over 50 years), whereas as I describe above, no such vaccine yet exists for malaria.

Finally, while superficially the symptoms of yellow fever and malaria may seem similar (fever, nausea, aches), other manifestations of the disease can be very different. Yellow fever is technically considered a hemorrhagic disease, since it can cause increased tendency to bleed in patients. Also, in some patients, the initial symptoms are followed by an acute liver phase, causing jaundice which can turn the patient yellow (and hence the name). Malaria can also affect the liver, and cause ild jaundice, but usually not to the extent of yellow fever.  Once a patient has been diagnosed with yellow fever, there is no specific treatment, and the patient is merely treated based on symptoms, to ease their discomfort. Vaccination is the mainstay of control of this disease, and has been very successful in many places; the total number of worldwide cases is estimated by the World Health Organization to be around 300,000, with 20,000 deaths, mainly in Africa.

The burden of malaria is also mainly felt in Africa, though the number of cases and deaths is vastly higher – globally, there are approximately 200 million cases of malaria in 2010, with almost 700,000 deaths. Along with the general symptoms of fever and nausea, the most dangerous manifestation of malaria is when it causes cerebral symptoms; this is usually only caused by Plasmodium falciparum malaria, and can lead to impaired consciousness, coma and even death. Also in contrast to yellow fever,  the mainstay of control is a combination of prevention (mostly with vector control, i.e. using bednets, indoor residual spraying and destruction of breeding habitats and larvae) and treatment (using a variety of medications).

Treatment and Management of Malaria Parasite

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QUESTION

What are the treatments and management of malaria?

ANSWER

Treatment is actually part of the strategy for managing malaria, so I will come back to that later. The other main ways in which malaria is controlled is through prevention, diagnosis (followed by treatment if necessary) and education.

1) Prevention:

There are a number of ways to prevent malaria. These can be placed into two categories: medication and vector protection.

For medication, there are drugs you can take to prevent the malaria parasite from developing after someone is bitten by an infected mosquito. These drugs are known as “chemoprophylaxis.”

There are several different kinds, such as doxycycline, mefloquine (marketed as Lariam), atovaquone-proguanil (marketed as Malarone) and chloroquine—the type you use depends on the type of malaria present in the area. For example, in much of Africa and India, malaria is resistant to chloroquine, so this cannot be used as a prophylactic. In parts of Thailand, resistance to mefloquine has emerged. However, if the appropriate type of prophylaxis is used, it is very effective against malaria.

The problem is that these drugs have not been tested for long-term use, can be expensive and may have side-effects. Therefore they are of limited use for people who live in areas where malaria is endemic, and are more appropriate for travelers who are in malarial areas for short amounts of time. However, anti-malarial medication may be used in a very specific way for people at particularly high-risk for malaria, such as pregnant women and young children. In these cases, the high-risk individuals receive a dose or series of doses of malaria medication in order to prevent malaria. This form of prevention is known as intermittent preventive therapy (IPT).

Vector prevention involves protecting oneself against getting bitten by mosquitoes. This can involve wearing long-sleeved clothing in the evenings and at night, when malaria mosquitoes are most active, or wearing insect repellent on exposed skin. Indoor residual spraying, whereby repellent and insecticides are sprayed inside the house, can also be used to bring down the number of mosquitoes.

Another very effective technique for preventing malaria is to sleep under a long-lasting insecticide-treated bednet. The mesh acts as a barrier against the mosquitoes, and the insecticide impregnated in the mesh further repels the mosquitoes and prevents them from biting through the mesh.

2) Diagnosis

Diagnosis is considered a crucial step in controlling malaria, since it ensures that people are receiving correct medication, whether for malaria or for another condition which is causing their symptoms. Currently, the most commonly observed form of diagnosis is through microscopy of thick and thin blood films, which can be stained if necessary. These should be read by a qualified technician to determine both the species of malaria infection and the intensity of parasitaemia (number of parasites in the blood).

More recently, other methods for diagnosis have emerged. These include the use of rapid diagnostic tests (RDTs) which utilize a drop of blood applied to a reagent strip which very quickly reacts to show whether the patient is infected with malaria. While considered generally more sensitive than blood films, some RDTs don’t test for all types of malaria parasite, and many require that the reagents be kept cold in order for the test to be effective, which can be a problem in some developing countries.

Perhaps the most sensitive test for malaria is through PCR, which can theoretically detect a single malaria parasite in a drop of blood, and also determine the species. However, measures of infection intensity require an alternative form of PCR, called real-time PCR, which can be technologically challenging. All forms of PCR require a lot of expensive equipment and reagents, trained technicians and take several hours to run.

3) Treatment

Malaria treatment can be determined based on the diagnostic results, as well as other factors, such as:

  • The area where the infection was acquired and its drug-resistance status
  • The clinical status of the patient
  • Any accompanying illness or condition
  • Pregnancy
  • Drug allergies, or other medications taken by the patient

Most uncomplicated (i.e. not severe) cases of P. falciparum can be treated with oral medication, such as artemisinin-based combination therapies (ACTs). Artemisinin is given in combination with another anti-malarial drug in order to prevent resistance from developing in the parasite. Patients who have complicated (severe) P. falciparum malaria or who cannot take oral medications should be given the treatment by continuous intravenous infusion, with quinine recommended by WHO as the first-line treatment.

Other drugs, which are used in some settings, are considered second-line or alternative forms of treatment. These include:

  • chloroquine (very rarely used for P. falciparum, due to widespread resistance)
  • atovaquone-proguanil (Malarone®)
  • mefloquine (Lariam®)
  • quinine
  • quinidine
  • doxycycline (used in combination with quinine)
  • clindamycin (used in combination with quinine)

In addition, primaquine is active against the dormant parasite liver forms (hypnozoites) and prevents relapses, for patients with P. vivax or P. ovale malaria. Primaquine should not be taken by pregnant women or by people who are deficient in G6PD (glucose-6-phosphate dehydrogenase). Patients should not take primaquine until a screening test has excluded G6PD deficiency.

4) Education

Through education, people living in at-risk areas for malaria transmission can learn about ways to prevent the disease (see above), as well as what to do if they suspect they are infected (i.e. seek diagnosis). Similarly, education is important for travellers visiting malarial areas, so they know the best ways in which to avoid being infected.

Malaria’s Impact on Tourism

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QUESTION

How is malaria’s impact on tourism?

ANSWER

These days, with effective preventative measures such as prophylactic medication and long-lasting insecticide treated bednets, the risk of contracting malaria as a tourist is greatly reduced. However, there is some evidence that the risk of contracting malaria is a deterrent for some tourists, particularly during high transmission periods of the year, in certain places.

For example, in South Africa, a group of researchers surveyed tourist facilities in KwaZulu-Natal and found that risk of contracting malaria was the major cause behind lack of bed occupancy. Improving tourists’ awareness of how the disease is transmitted and ways of preventing infection will go a long way to reducing the negative impact of the disease on the tourism industry in malarial countries.