Is malaria a problem for a tourist in Guyana?

QUESTION

Is malaria a problem for a tourist to Guyana?

ANSWER

Yes, malaria is something you should be aware of when travelling to Guyana. Transmission occurs in all areas under 900m in Guyana, including Georgetown. If you are visiting these areas, you should consider taking prophylactic medication to prevent malaria, such as atovaquone-proguanil (sold as Malarone), doxycycline or mefloquine (Lariam). You should also consider other preventative measures while you are there, such as sleeping under a bednet, wearing long-sleeved clothing (especially in the evenings and at night) and covering exposed skin with insect repellent.

Malaria in Namibia or South Africa

QUESTION

Is there a risk of catching malaria in Namibia or South Africa

ANSWER

Yes. According to the CDC, malaria is present in the following areas of Namibia: Kunene, Ohangwena, Okavango, Omaheke, Omusati, Oshana, Oshikoto, and Otjozondjupa and the Caprivi Strip. In addition, malaria is present in South Africa in northeastern KwaZulu-Natal Province as far south as the Tugela River, Limpopo (Northern) Province, and Mpumalanga Province. It is also present in Kruger National Park.

If you are visiting these areas, it is recommended you take prophylactic medication (such as doxycycline, mefloquine or atovaquone-proguanil) and sleep under a bednet. Other preventative measures against mosquito bites, such as wearing long-sleeved clothing and insecticide on exposed skin (especially in the evenings and at night) are also recommended.

Malaria in Haiti

QUESTION

I just recently returned from Senegal, 60 days ago, in which I had taken Malaria medicine; Chloroquine. I am heading to Haiti in 5 days, and wondering if I am in need of taking Malaria medicine again, or was the time frame close enough that it would be fine to go without.

ANSWER

You are only protected against malaria while you are taking the anti-malarial prophylactic medicine. All of Haiti is considered at risk for malaria, and so you should talke anti-malarial medication throughout the duration of your stay, plus the required time afterwards (depending on which type of prophylactic medication you take). Chloroquine is considered suitable as an anti-malarial for Haiti, as is atovaquone-proguanil (Malarone), doxycycline and mefloquine (Lariam).

Prevention of Malaria

QUESTION

How do I prevent malaria?

ANSWER

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 travellers 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 repells the mosquitoes and prevents them from biting through the mesh.

Antimalarial Drug Therapeutic Life

QUESTION

Why do some antimalarial drugs have long therapeutic life while others have short therapeutic lives?

ANSWER

Different anti-malarial drugs target slightly different aspects of the malaria Plasmodium parasite, and so are made with different chemical structures.

The differences in therapeutic life across different malaria drugs has to do with the specific pharmacokinetic properties of the chemical compounds from which the drugs are made. Even drugs designed around the same principal chemical compound can persist for different amounts of time in the human body, depending on the other chemicals with which the active compound is bound. The length of time it takes for a chemical compound to halve in concentration, or for its pharmacological effect to reduce by half, in the human blood stream is known as its “half life.”

For example, the common anti-malarial drug chloroquine has a half life of about 10 days, and is based on a chemical compound called 4-aminoquinoline. However, another drug also based on 4-aminoquinoline, called amodioquine, has a half life of only 10 hours.

Proguanil (combined with atovaquone in the drug Malarone) is dihydrofolate reductase inhibitor with a half life of about 16 hours, while mefloquine (sold as Lariam), is made from quinoline methanol and has a half life ranging from 10-40 days. These differences in length of therapeutic action also affect the efficacy of the compounds against malaria at various stages in its progression, and can also be implicated in the propensity to resistance developing to the drug in the malaria parasite.

Malaria Symptoms, Cures, and Prevention

QUESTION

What is malaria cure, prevention, symptom and course?

ANSWER

I am not sure what you mean by “course” – however, links to information on malaria treatment, prevention and symptoms can be found on the main page of our website. For your convenience, I have provided them here:

As for malaria treatment, I have copied here an earlier answer in response to a question about malaria cures:

Malaria can be cured with a number of different medications, depending on then type of malaria and how far the disease has been progressed.

For standard, non-complicated Plasmodium falciparum malaria, the World Health Organisation recommends use of artemisinin-based combination therapies (ACTs), such as Coartem. This is due to increasing levels of resistance to chloroquine in many parts of the world. Indeed, even though chloroquine is still used in many places as first-line treatment against P. vivax, P. malariae, P. ovale and P. knowlesi uncomplicated malaria, there is some evidence that resistance to this treatment is also emerging, for example in P. vivax in parts of south-east Asia.

In cases where malaria infection has progressed to a stage where oral administration of medication is not possible, or where cerebral symptoms are suspected, the usual treatment option is intravenous quinine.

In addition, P. vivax and P. ovale malaria parasites are able to produce forms (called hypnozoites) which can become dormant in liver hepatocyte cells after the blood stages of the infection have been cleared. These dormant forms can become reactivated weeks or even months or years after the initial infection, which is called a “relapse” of the infection. One drug, called primaquine, is able to kill these liver stages, and so patients with either of these types of malaria should also discuss the possibility of taking primaquine.

Apart from these first-line treatments, there are other medications which are used against malaria, both prophylactically as well as for treatment. These include orally-administered quinine, pyrimethamine, mefloquine, proguanil, atovaquone and sulfonamides.

 

Which Anti Malarial for South-East Asia?

QUESTION

We are in our 70s and will be on a cruise from Siem Reap to Ho Chi Minh. Which anti malarial would be most effective for these areas?

ANSWER

The main thing to consider when travelling to south-east Asia is that there are areas where some of the malaria is resistant to mefloquine (commonly sold as Lariam), and therefore this drug is not appropriate as an anti-malarial in these regions.

Chloroquine resistance is also rife throughout the region, although this drug is rarely used as a malaria prophylactic drug. However, apart from this, the choice of anti-malarial depends to a large extent on personal preferences.

The two main types recommended by the CDC for travel to south-east Asia are atovaquone-proguanil (marketed commonly as Malarone) and doxycycline. The former is associated with very few side effects, is taken once a day, and needs to be taken for a week after returning from the malarial area. However it is also very pricey! Doxycycline, on the other hand, is very cheap, but many people experience high sun sensitivity which can lead to severe sun burn if sufficient care is not taken. It also has to be taken for a full four weeks after returning from the malarial area.

How is Malaria Treated

QUESTION

How is malaria treated?

ANSWER

This answer is copied from an earlier question about the various available cures for malaria.

Malaria can be cured with a number of different medications, depending on then type of malaria and how far the disease has been progressed.

For standard, non-complicated Plasmodium falciparum malaria, the World Health Organisation recommends use of artemisinin-based combination therapies (ACTs), such as Coartem. This is due to increasing levels of resistance to chloroquine in many parts of the world. Indeed, even though chloroquine is still used in many places as first-line treatment against P. vivax, P. malariae, P. ovale and P. knowlesi uncomplicated malaria, there is some evidence that resistance to this treatment is also emerging, for example in P. vivax in parts of south-east Asia.

In cases where malaria infection has progressed to a stage where oral administration of medication is not possible, or where cerebral symptoms are suspected, the usual treatment option is intravenous quinine.

In addition, P. vivax and P. ovale malaria parasites are able to produce forms (called hypnozoites) which can become dormant in liver hepatocyte cells after the blood stages of the infection have been cleared. These dormant forms can become reactivated weeks or even months or years after the initial infection, which is called a “relapse” of the infection. One drug, called primaquine, is able to kill these liver stages, and so patients with either of these types of malaria should also discuss the possibility of taking primaquine.

Apart from these first-line treatments, there are other medications which are used against malaria, both prophylactically as well as for treatment. These include orally-administered quinine, pyrimethamine, mefloquine, proguanil, atovaquone and sulfonamides.

 

Medicines to Prevent Malaria?

QUESTION

Which medicines are used to prevent malaria?

ANSWER

There are a number of drugs used to prevent malaria infection, known as malaria prophylactic medication. These vary in terms of how they are taken, how long they are taken for, how much they cost and the typical side effects people experience while they are taking them. In addition, some are recommended more highly for certain types of malaria or certain regions of the world, due primarily to the emergence of resistance in certain areas.

The most common forms of malaria prophylaxis used are doxycycline, atovaquone/proguanil (sold under the brand name Malarone), chloroquine (sold as Aralen) and mefloquine (sold as Lariam). More information on these, on other types of prophylaxis and malaria prevention in general can be found on our Malaria Prevention page.

How is Malaria Cured?

QUESTION

How is malaria cured?

ANSWER

Malaria can be cured with a number of different medications, depending on then type of malaria and how far the disease has been progressed.

For standard, non-complicated Plasmodium falciparum malaria, the World Health Organisation recommends use of artemisinin-based combination therapies (ACTs), such as Coartem. This is due to increasing levels of resistance to chloroquine in many parts of the world. Indeed, even though chloroquine is still used in many places as first-line treatment against P. vivax, P. malariae, P. ovale and P. knowlesi uncomplicated malaria, there is some evidence that resistance to this treatment is also emerging, for example in P. vivax in parts of south-east Asia.

In cases where malaria infection has progressed to a stage where oral administration of medication is not possible, or where cerebral symptoms are suspected, the usual treatment option is intravenous quinine.

In addition, P. vivax and P. ovale malaria parasites are able to produce forms (called hypnozoites) which can become dormant in liver hepatocyte cells after the blood stages of the infection have been cleared. These dormant forms can become reactivated weeks or even months or years after the initial infection, which is called a “relapse” of the infection. One drug, called primaquine, is able to kill these liver stages, and so patients with either of these types of malaria should also discuss the possibility of taking primaquine.

Apart from these first-line treatments, there are other medications which are used against malaria, both prophylactically as well as for treatment. These include orally-administered quinine, pyrimethamine, mefloquine, proguanil, atovaquone and sulfonamides.

For more information, see the WHO recommendations for malaria treatment.