Why does malaria only occur in hot countries?

Why does malaria only occur in hot countries?

For nearly a century, scientists thought that malaria could only spread in places where it is really hot. That’s because malaria is spread by a tiny parasite that infects mosquitoes, which then infect humans — and this parasite loves warm weather.

Why is malaria near the equator?

For example, the most severe strain of malaria cannot be transmitted in temperatures under 68 degrees Fahrenheit because the parasites themselves cannot complete their life cycle inside the mosquitoes. The warmest climates close to the equator thus have the highest rates of malaria transmission.

Does malaria mainly affect tropical regions?

Malaria risk areas Malaria is found in more than 100 countries, mainly in tropical regions of the world, including: large areas of Africa and Asia. Central and South America. Haiti and the Dominican Republic.

Why is malaria a problem in the tropical and subtropical regions of Africa?

Malaria occurs mostly in poor, tropical and subtropical areas of the world. Africa is the most affected due to a combination of factors: A very efficient mosquito (Anopheles gambiae complex) is responsible for high transmission.

How is malaria related to climate?

In regions already affected by the disease, the impact of climate on malaria is mainly related to changing rainfall patterns, or increased flooding risk. That’s around 700 million more people at risk. Just half a degree centigrade increase in temperature could mean an increase in mosquito abundance of up to 100%.

How does climate affect malaria?

An increase in temperature, rainfall, and humidity may cause a proliferation of the malaria-carrying mosquitoes at higher altitudes, resulting in an increase in malaria transmission in areas in which it was not reported earlier. In dry climates, heavy rainfall can provide good breeding conditions for the mosquitoes.

How does location affect malaria?

The incidence of malaria is generally lower in urban areas than in rural areas. There are a number of reasons for this: While there is plenty of space for vector breeding in rural villages, mosquito breeding sites in urban areas are limited because more space is covered by houses.

Why is malaria on the rise?

An increase in temperature, rainfall, and humidity may cause a proliferation of the malaria-carrying mosquitoes at higher altitudes, resulting in an increase in malaria transmission in areas in which it was not reported earlier.

How is malaria spread in tropical environment?

Malaria is caused by a parasite called Plasmodium falciparum and is transmitted by Anopheles mosquitoes (pictured above). When an Anopheles mosquito bites a person infected with the malaria parasite, the mosquito becomes a carrier of the disease.

Why is malaria so common in Africa south of the Sahara?

It may be surprising that most cases occur on the African continent. Malaria is common in the area south of the Sahara Desert (called sub-Saharan Africa) because the disease spreads almost entirely in poor regions with tropical and subtropical climates. The local weather allows for transmission to occur year round.

What is the environment of malaria?

The geographic distribution of malaria depends on the climate. Regions where the climate is ideal for the Anopheles mosquitoes that transmit malaria parasites are more prone to the disease. Anopheles mosquitoes thrive in regions with warm temperatures, humid conditions, and high rainfall.

What are the main causes of malaria?

Malaria is caused by the Plasmodium parasite. The parasite can be spread to humans through the bites of infected mosquitoes.

Where does most of the world’s malaria occur?

Malaria occurs mostly in poor, tropical and subtropical areas of the world. This map shows an approximation of the parts of the world where malaria transmission occurs. Africa is the most affected due to a combination of factors: A very efficient mosquito (Anopheles gambiae complex) is responsible for high transmission.

How is temperature related to the growth cycle of malaria?

Malaria parasites can complete their growth cycle in the mosquitoes (“extrinsic incubation period”). Temperature is particularly critical. For example, at temperatures below 20°C (68°F), Plasmodium falciparum (which causes severe malaria) cannot complete its growth cycle in the Anopheles mosquito, and thus cannot be transmitted.

What are the parasites that cause the symptoms of malaria?

The blood stage parasites are those that cause the symptoms of malaria. When certain forms of blood stage parasites (“gametocytes”) are picked up by a female Anopheles mosquito during a blood meal, they start another, different cycle of growth and multiplication in the mosquito.

How is malaria transmitted from one person to another?

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).