Increased Dengue and Reduced Malaria – As Africa gets hotter, mosquito control strategies may need to change

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Jason Rasgon, Pennsylvania State University

(Conversation) Malaria-borne anopheles may lose the fight against climate change in Africa because they become too warm and uncomfortable. But the new enemy is on the horizon.

If the temperature is too high for malaria parasites and the anopheles that transmit them, another mosquito called the Aedes aegypti may be in a good position to breed. This new mosquito poses the threat of many viruses that it carries.

For over 20 years, I’ve been working on vector-borne diseases such as malaria and multiple arthropod-borne viral diseases. A new paper by Erin Mordecai and his colleagues published at Lancet Planetary Health not only makes many of Africa vulnerable to malaria due to high temperatures caused by global warming, but also spreads other mosquito-borne diseases. Looking deeply into the future that will be.

It’s too hot for one mosquito. Just right

New research suggests that climate change could lead to a reduction in malaria in sub-Saharan Africa. Malaria is one of Africa’s leading murderers, with more than 200 million cases and 400,000 deaths each year. Parasites and the Anopheles mosquitoes that transmit them are spread throughout sub-Saharan Africa. However, malaria is not the only vector-borne disease of concern in Africa. Arthropod-borne viruses – or arboviruses – are also widespread on the continent.

Hamadaraka itself is known to infect several viruses, such as the Mayaro virus and the Onyon-nyon virus. However, the most important viral vector is the mosquito Aedes aegypti, which infects many different viruses, including Dengue virus, the most widespread mosquito-borne virus in the world.

Aedes aegypti and dengue virus (and other viruses) are spread throughout Africa. However, as most surveillance focuses on malaria, they are and are underestimated as public health threats. In addition, some viral manifestations of dengue can mimic a malaria infection.

Aedes aegypti mosquitoes and arboviruses perform better in hotter environments than anopheles mosquitoes and malaria parasites. Also, as environmental conditions may become warmer and malaria may decline over the next 60 years, viral pathogens such as dengue fever can cause rashes, fever, body pain, and even more serious life-threatening bleeding and shock symptoms. And the research ends.

New diseases are increasing

Vector control efforts that are effective against indoor feeding anopheles, such as insecticide-treated mosquito nets and insecticides, do not work against the outdoor eating eclipse Aedes aegypti. Also, unlike malaria, there are no drugs or cures for dengue fever and other viral pathogens.

According to this new research paper, outbreaks of dengue fever and other viruses will replace the disappearance of the malaria epidemic seen today if public health strategies are not adapted to new climate realities.

Mordecai and colleagues used data from multiple sources to develop and validate models of potential malaria and dengue infections. They showed that malaria infections were most effective at about 25 degrees Celsius, whereas dengue infections were more effective at warmer temperatures at 29°C.

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By the year 2080, we expect a significant reduction in malaria cases as Anopheles recedes into cooler areas as climate change makes much of Africa hotter in the next century. Dengue, on the other hand, will be widespread as climate and urbanization create a wider habitat for Aedes aegypti.

Because Aedes aegypti already exists in sub-Saharan Africa, and viral pathogens such as the Dengue virus exist, Mordecai and colleagues say that public health activities have led to the emergence of new malaria-causing surveillance and control of arboviruses. Makes a compelling argument that it should be considered a problem.

In fact, their results suggest that a widespread arbovirus infection may already have occurred, but it is not fully recognized under our nose.

This article was republished from Conversation under the Creative Commons License. Read the original article here: https://theconversation.com/more-dengue-fever-and-less-malaria-mosquito-control-strategies-may-need-to-shift-as-africa-heats-up-145650..