QUESTION
Can one have sexual intercourse during malaria infection?
Can malaria be transmitted by sexual intercourse?
ANSWER
Malaria cannot be transmitted by sexual intercourse. It is usually transmitted via the bite of an infected mosquito. Because the parasites infect red blood cells, malaria can also be transmitted via blood transfusion (if the blood is not screened beforehand), organ transplant, and from a mother to her unborn baby, either during childbirth or via the placenta.
QUESTION
How many countries are malaria infected?
ANSWER
As of 2010, there were 108 countries which were listed as having endemic malaria—that is, malaria which was transmitted within the country. This includes 43 countries in Africa, 10 countries in south-east Asia, 13 countries in the Eastern Mediterranean (which includes most of Central Asia and parts of North and East Africa—90% of the malaria burden in this region is suffered by Sudan, Afghanistan, Pakistan and Somalia), 10 countries in the Western Pacific (though this region constitutes less than 1% of global malaria cases) and 23 malaria-endemic countries in the Americas.
QUESTION
Where are the most deaths of malaria?
ANSWER
Over 90% of the deaths from malaria occur in sub-Saharan Africa, and in children under the age of five. According to the World Health Organisation’s 2011 World Malaria Report, the countries with the five highest numbers of reported malaria deaths for 2010 are (and number of reported deaths): Kenya (26,017 deaths), Democratic Republic of Congo (23,476), Tanzania (15,867), Burkina Faso (9,024) and Uganda (8,431).
However, it is important to note that this indicates the number of reported deaths that were confirmed as malaria; there are other countries in Africa which may have similar levels of malaria mortality but insufficient health infrastructure for accurate diagnosis of cause of death or reporting. Even in countries where reporting levels are high, causes of death are not always accurately determined.
QUESTION
What is malaria’s scientific name?
ANSWER
The genus name for the single-celled parasite which causes malaria is Plasmodium. In the genus, there are five species which infect humans: Plasmodium falciparum (the most deadly kind), P. vivax, P. ovale, P. malariae and P. knowlesi.
QUESTION
Hi, I am in Goa and so far have not been bitten by anything. I am taking anti malaria tablets which I do not like. My question is this. If I do not receive any bites do I need to complete the course when I get home?
ANSWER
It is always better to complete the course of anti-malarials, just in case you actually did get bitten but just did not notice it. However, in some cases, the side-effects of anti-malarials can be uncomfortable and unpleasant, so I understand your dilemma. Just remember that there is always a risk of contracting malaria if you stop your anti-malarials early.
We at MALARIA.com are very interesting in learning about people’s experiences with anti-malarial drugs. Please take a few minutes to complete our Malaria Survey. All answers are anonymous and we will post the results on MALARIA.com.
QUESTION
What is malaria, and drug binding site?
ANSWER
Malaria is caused by a single-celled protozoan parasite of the genus Plasmodium. Five kinds of Plasmodium are known to infect people: P. falciparum, P. vivax, P. ovale, P. malariae and P. knowlesi.
There is no one drug binding site with respect to malaria: different anti-malarial drugs have different modes of action, and not all are well described. I will briefly outline the proposed mechanism of action of two of the most common types of anti-malarials: artemisinin (and derivatives) and chloroquine (quinine is thought to act similarly to chloroquine).
Artemisinin is thought to have anti-malarial properties by virtue of possessing an endoperoxide moiety, or double oxygen bridge (-Carbon-Oxygen-Oxygen-Carbon). In the presence of intracellular free ion, this moiety is converted by a chemical reaction to “free radicals”, atoms with unpaired electrons which are highly reactive. The free radicals act as alkylating agents and induce cell death, but only those that are already pathologically crippled, for example due to malaria infection. Another hypothesis is that the free radicals directly damage the malaria parasite.
Chloroquine is thought to act by causing buildup of the toxic by-product of hemoglobin metabolism, heme – the malaria parasite usually converts heme to hemozoin, a non-toxic crystal, and stores it in the digestive vacuole. When chloroquine diffuses into an infected red blood cell, it reacts with heme to “cap” it, preventing further conversion into hemozoin. Moreover, chloroquine also converts hemozoin into a highly toxic substance called the FP-Chloroquine complex. This build-up of toxicity leads to breakdown of the cell membrane, and eventual cell death and autodigestion.
QUESTION
I live in Nigeria. Good friend of mine complained of headaches in Dec 2011. Did an MRI went to Germany had a general check up. Back in Nigeria in January, headaches increase, she gets blind in one eye, following day the other eye, now in Germany where they have induced her into a coma. They said that she got a brain Haemorrage from the malaria. Can malaria bring blindness. What are the chances of surviving and getting back eyesight.
ANSWER
Although rare, brain hemorrhage is sometimes associated with severe cerebral malaria (caused by infection with Plasmodium falciparum, the most deadly form of malaria). This bleeding in the brain could cause blindness—whether the visual impairment is permanent or not depends on the extent of the bleeding and how much damage it caused.
I have found one case in the literature where severe malaria caused a brain hemorrhage which resulted in permanent blindness, and the authors report their case is only the second they have heard of, so this is rare indeed. Similarly, her survival will depend on how well she responds to treatment, which will likely be intravenous quinine, at least at first. Given that she is in Germany, where health care is excellent, I would say her chances are as good as they would be anywhere else in the world. I hope she makes a full and swift recovery!
QUESTION
Up to now how many people died of malaria?
Up to now how many people died of Hepatitis A?
Up to now how many people died of Cholera?
ANSWER
It is believed that malaria is singly responsible for the most deaths of humans in history. However, the exact number is impossible to know. Our modern concept of disease as caused by a particular organisms or pathogen is very new, having only really developed in the 19th century, though dating back to the work of Anton van Leeuwenhoek in the late 17th century (he has since been described as “the father of microbiology”).
As such, in the past, diseases were often mistaken for each other, and particularly since malaria has such general symptoms (fever, aches, chills—these are commonly seen in many other illnesses as well), it is hard to determine what people actually died from malaria and which died from other causes. Indeed, this difficulty remains today, making it hard to estimate accurately the number of people who die from malaria even now. The World Health Organisation currently estimates that approximately 700,000 people died last year of malaria, from close to 700 million cases – this actually represents a very low death rate, thanks is large part to global efforts to improve access to diagnosis and treatment.
Hepatitis A is far less common than malaria; there are an estimated 1.4 million cases per year. Most of these are asymptomatic or mild, with a low fatality rate (4 deaths per 1000 people infected in people under 50; that rises to 17.5 per 1000 for people over 50, as older people tend to have more severe manifestations of the disease and a greater risk of subsequent liver complications – note that these data are from the CDC back in 1991). There is a very safe and effective vaccine available against hepatitis A virus (HAV)—almost 100% of people given the vaccine develop antibodies against infection.
Cholera is slightly more common than HAV (3-5 million estimated cases each year, according to the World Health Organisation) but similarly, most cases are of mild severity. Less than 20% of patients develop “typical” cholera with severe, life-threatening dehydration. 100,000-120,000 people are estimated to die from cholera each year.
QUESTION
I was wondering is it possible for a father who contracted malaria in the Korean War to pass it to his unborn child.
ANSWER
No. Malaria can only be transmitted by the bite of an infected mosquito, and in rare cases, through infected blood, for example from a blood transfusion or organ transplant. Mothers can transmit malaria to their unborn babies via the placenta or through blood during childbirth (this is called congenital malaria) but there is no way that a father could pass malaria on to his child.
QUESTION
Has the geographic range of malaria increased over the past 20 – 30 years? I have read that preventative measures have helped lower rates of infection, but I’m interested in the extension of the range itself.
ANSWER
That is a very interesting question, and one that garners quite a lot of debate. Preventative measures have actually also helped to limit the range of malaria globally. For example, malaria used to be relatively common in the Mediterranean basin and south-eastern United States, but control measures (mainly based around killing mosquitoes and removing suitable mosquito habitat) has largely eradicated malaria from these areas.
However, there is concern that on-going and future climate change has and will change the distribution of malaria globally. For example, some predictions have suggested that malaria might be able to re-establish itself in the Mediterranean and Middle East, due to higher rainfall and higher winter minimums of temperature. Additionally, malaria may be able to spread to higher altitudes in areas where it is already present at low elevations. This is of huge concern in places like Kenya: Nairobi, the capital city (with around 5million people), sits at 1660 m altitude, and as such currently has generally negligible levels of malaria transmission. However, if climate change enables malaria to move up to this altitude, a huge number of people will be at additional risk of infection. Worryingly, there is some evidence from the Kenyan highlands that these changes are already underway.
Having said this, there are also parts of the world which might see malaria transmission ease as a result of climate change. This is particularly the case where rainfall is expected to decrease, or change significantly in relation to temperature. Moreover, some scientists think that on-going control efforts, particularly with respect to the distribution of bednets, vector control and greater coverage of diagnosis and treatment will continue to reduce the geographical spread of malaria over and beyond the changes associated with climate change. These scientists have compiled a map of Plasmodium falciparum transmission now as compared to data from before control interventions were rolled out—the reduction of transmission risk in many parts of the world, are clear to see (see below).
Maps showing changes in transmission risk and endemicity of Plasmodium falciparum malaria between approximately 1900 (a) and now (b). (c) shows the balance of change in malaria transmission between the two time periods: the higher the negative number, the greater the reduction in malaria transmission. A positive number indicates increased malaria transmission. The different classes of malaria transmission risk are as follows: hypoendemic, prevalence < 10%; mesoendemic, PR ≥ 10% and < 50%; hyperendemic, prevalence ≥ 50% and < 75%; holoendemic, prevalence ≥ 75%. Image reproduced here from Gething et al., (2010), 'Climate change and the global malaria recession', in Nature, volume 465, pages 342-345.