How easily is malaria passed between humans?

QUESTION

Can malaria be passed between humans if one has a bloody nose or if sex tears the vagina and a small bleed occurs?

ANSWER

It is extremely unlikely malaria would be transmitted via transfer of small amounts of blood. The only documented examples of direct transmission of malaria between humans is during blood transfusion, organ donation and from a mother to her unborn child, all of which require transfer of very large volumes of blood or the transfer of a specific organ containing malaria parasites. In the case of a mother transmitting malaria to her child, it either occurs across the placenta (again, via blood) or via the large amounts of blood which can be exposed during childbirth.

Malaria Transmission by Contact?

QUESTION

If you come in contact with someone who has had malaria can you get it from them?

ANSWER

No. It is not transmissible directly between people. Most transmission of malaria occurs when a mosquito infected with the malaria parasites bites someone, who then may get malaria. In some cases, transfers of organs or large quantities of infected blood (such as during blood transfusion) may also result in transmission, though this is more rare, and screening of blood reduces the probability of it occurring. Malaria can also be transmitted from a mother if she has malaria to her unborn child via the placenta, or via blood during childbirth. This is called congenital malaria.

At what age can you get malaria?

QUESTION

What age do you get malaria?

ANSWER

Malaria is transmitted by the bite of an infected mosquito, and therefore any one living  where malaria is present, at any age,  is susceptible. To prevent malaria,  sleep under a long-lasting insecticide treated bednet; make sure it is re-dipped in insecticide every year or so to maintain its efficacy. The mosquitoes which transmit malaria tend to feed at night, and so protecting yourself and your home during the evening, night and early morning is crucial. Maintaining good screens on all windows and doors can be a very effective way of preventing mosquitoes from entering, and in many parts of the world, people spray inside with insecticides to reduce the number of mosquitoes yet further. Wearing long-sleeved clothing at night and in the evenings can also prevent bites.

Pregnant women though, due to changes to the mother’s immune system and also perhaps due to the physiology of the placenta, are very vulnerable to malaria. There is also the risk (up to 33% in some studies) that malaria will pass directly from the mother to the baby, either through the placenta or in blood during childbirth—this is called “congenital malaria,” and can manifest as early as 1 day after delivery but a late as months after. The symptoms are similar to that of adult malaria, with fever, anaemia, lethargy, etc.

Even if the unborn baby does not get congenital malaria, it can be effected by its mother having malaria during pregnancy, with possible low birth weight, anaemia and even spontaneous abortion—abortion rates due to malaria can vary between 15-70%.

Given these negative effects, it is very important to protect pregnant women against malaria, and bednet distribution schemes in many places target these women. In high transmission settings, women may also be offered intermittent preventive therapy (IPT) which consists of at least two doses of anti-malarial medication, usually once during the second and once during the third trimester.

Ingestion of Malaria Blood

QUESTION

If someone were to eat/ingest the blood of an infected individual would they become infected with malaria? If an infected person’s blood was on their hands and they handled food, would eating the food put others at risk for malaria?

ANSWER

No, you would not get infected with malaria, as the malaria parasites must be transmitted into a person’s blood directly in order for them to be infected. As such, most transmission only occurs via mosquitoes: when a mosquito bites a person infected with malaria, it may pick up some of the malaria parasites while it feeds on the person’s blood. When it then goes to bite another person, after the parasite has replicated and changed inside the mosquito, it can pass the malaria on to the next person, again when it bites them and drinks the person’s blood.

Additionally, in some cases malaria can be transmitted by blood transfusion or organ donation, or from a mother to her unborn baby via the placenta, or through blood passed in childbirth. If you ate/drank malaria-infected blood, the parasites would be broken down and destroyed by your stomach acid.

Is Malaria Contagious Between Humans?

QUESTION

If someone has malaria, is it contagious?

ANSWER

No. Malaria cannot be transmitted via touching or saliva or air. In virtually all cases, it is only transmitted by the bite of an infected mosquito, and so cannot be passed from one person to another. There are a few exception—because the parasite lives in certain organs and in the blood, it can sometimes be transmitted via blood transfusion or organ transplant. It can also pass via the placenta from a mother to her unborn child, or to the child during childbirth.

Malaria: Mode of Transmission

QUESTION

What is the mode of transmission of Malaria?

ANSWER

Malaria is transmitted normally via the bite of an infected mosquito. These mosquitoes, always female and of the genus Anopheles, carry malaria parasites in their salivary glands. The parasites, at this part of their life cycle known as sporozoites, are introduced into the host’s blood when the mosquito takes a blood meal. From there, the sporozoites travel to the liver, reproduce (this process may take several weeks), then finally re-enter the blood stream. At this point, the patient will begin to experience symptoms. Eventually, the malaria parasites change again, into gametocytes, which are picked up by another mosquito, again when it bites the infected person. In this way, the life cycle of the malaria parasite continues.

Because malaria reproduces in the blood and in the liver, in some cases malaria can be transferred via organ transplant or blood transfusion. In addition, malaria parasites can cross the placenta, and so can be transmitted from a mother to her unborn child, either in the womb or during childbirth. This is known as congenital malaria.

Causes of Malaria

QUESTION

What are the causes of malaria?

ANSWER

Malaria is caused by a parasite called Plasmodium, which is transmitted via the bites of infected mosquitoes. In the human body, the parasites multiply in the liver, and then infect red blood cells. Usually, people get malaria by being bitten by an infective female Anopheles mosquito. 

Only Anopheles mosquitoes can transmit malaria and they must have been infected through a previous blood meal taken on an infected person. When a mosquito bites an infected person, a small amount of blood is taken in which contains microscopic malaria parasites. About 1 week later, when the mosquito takes its next blood meal, these parasites mix with the mosquito’s saliva and are injected into the person being bitten.

Because the malaria parasite is found in red blood cells of an infected person, malaria can also be transmitted through blood transfusion, organ transplant, or the shared use of needles or syringes contaminated with blood. Malaria may also be transmitted from a mother to her unborn infant before or during delivery (“congenital” malaria).

Malaria Transmission

QUESTION

How is malaria transmitted?

ANSWER

Malaria is caused by a parasite called Plasmodium, which is transmitted via the bites of infected mosquitoes. In the human body, the parasites multiply in the liver, and then infect red blood cells. Usually, people get malaria by being bitten by an infective female Anopheles mosquito. 

Only Anopheles mosquitoes can transmit malaria and they must have been infected through a previous blood meal taken on an infected person. When a mosquito bites an infected person, a small amount of blood is taken in which contains microscopic malaria parasites. About 1 week later, when the mosquito takes its next blood meal, these parasites mix with the mosquito’s saliva and are injected into the person being bitten.

Because the malaria parasite is found in red blood cells of an infected person, malaria can also be transmitted through blood transfusion, organ transplant, or the shared use of needles or syringes contaminated with blood. Malaria may also be transmitted from a mother to her unborn infant before or during delivery (“congenital” malaria).

Hereditary Malaria

QUESTION

Can malaria be passed on through heredity?

ANSWER

In the vast majority of cases, malaria is only transmitted via the bite of an infected mosquito.

However, if a pregnant woman becomes infected with malaria, she can pass the parasite to her unborn child via the placenta, or via blood transfer during childbirth. An infection in a newborn child, caused by infection in the mother during pregnancy, is known as “congenital malaria”. Otherwise, a child cannot “inherit” malaria from their parents, apart from the above case of congenital malaria.

Malaria Infectious?

QUESTION

Is malaria infectious?

ANSWER

Yes, malaria is considered an infectious disease, though it is very rarely transmitted directly between people, and virtually all of the time must be transmitted via the bite of a mosquito (of the genus Anopheles).

Because part of the life cycle of malaria occurs in red blood cells in the human host, if sufficient amounts of blood are shared between people, for example during a blood transfusion, malaria can also pass between them this way, though screening measures reduce the likelihood of this occurring. Similarly, an earlier part of the life cycle occurs in the liver, so transplant of this organ can also result in transmission.

Finally, malaria is able to pass through the placenta, and so can be transmitted from a mother to her unborn child in this way, or also via blood during childbirth. When a baby contracts malaria from each mother, either via the placenta or during childbirth, it is known as “congenital” malaria.