Malaria to Spread in Africa – Climate Change!

Guest Essay by Kip Hansen

You would think that science journalists have been carefully trained to research the topics they write about, especially in high-profile media outlets such as the New York Times.  It is a shame that careful back-grounding has become a thing of the past even in these prestigious newsrooms. 

The latest Climate Change alarm comes from a science journalist who should know better, Apoorva Mandavilli.  Her latest piece is titledHow Climate Change Is Spreading Malaria in Africa”.  

The lede to her story is this:

 “A new study offers a glimpse of the future by looking to the past. Mosquitoes that transmit malaria in sub-Saharan Africa have moved to higher elevations by about 6.5 meters (roughly 21 feet) per year and away from the Equator by 4.7 kilometers (about three miles) per year over the past century, according to the study.”

“That pace is consistent with climate change and may explain why malaria’s range has expanded over the past few decades, the authors said. The results have serious implications for countries that are unprepared to cope with the disease.”

The article was prompted by a recent study (yes, “There is a Study!”) that appeared in Biology Letters with the title: “Rapid range shifts in African Anopheles mosquitoes over the last century   by Carlson et al. (2023).

This study claims to have found “Mosquitoes that transmit malaria in sub-Saharan Africa have moved to higher elevations by about 6.5 meters (roughly 21 feet) per year and away from the Equator by 4.7 kilometers (about three miles) per year over the past century, according to the study.” 

I won’t quibble with their actual findings….it is a result of rather obtuse calculation across heterogenous data sets. But we catch the lead author, Colin Carlson, giving this quote to the Times:

“If this were random, and if it were unrelated to climate, it wouldn’t look as cleanly climate-linked.”

Our Times journalist, Mandavilli, said “A new study offers a glimpse of the future by looking to the past.”

Unfortunately, the neither the authors or Mandavilli seem to have looked far enough or closely enough into the past to realize that their conclusions and worries are not supported by real world historical facts. Other epidemiologists have taken notice, as reported in the “Discussion” section of the paper: 

“Others have disputed these conclusions, suggesting that they are irreconcilable with long-term progress towards malaria elimination, that trends in the region are better explained by lapsed control programmes and growing drug resistance, and that climate change is inconsistent with long-term trends at the continental scale.”

And these others have quite rightly disputed the conclusions, which totally fail to take into account several overriding facts:

1)  The worry isn’t that Africans might be bitten by mosquitoes – they will, always and almost everywhere in Africa (except the Sahara and other northern deserts).  It is about the locations of African malaria mosquito vectors (Anopheles spp.). 

2) But what is the real historical data about where in Africa malaria is a threat — where malaria is endemic?

That map is Malaria Transmission – not just where Anopheles  mosquitoes live.  That shows the history malaria transmission in Africa since 1900.

And closer to today?

This map shows where the species that is the reservoir of malaria has been actually found to have malaria in its blood — meaning the individual is sick with malaria or is a carrier of malaria.

What species is that?

“Reservoir:   Humans are the only important reservoir of human malaria. Mode of Transmission: Malaria is transmitted by the bite of an infective female Anopheles mosquito. Transfusion of blood from infected persons and use of contaminated needles and syringes are other potential modes of transmission.  Apr 2, 2014   MALARIA FACT SHEET  State of Georgia” (.pdf)

~ ~ ~ ~ ~

Reservoir and Vector in Malaria

Humans are the Reservoir of malaria – The Agent of malaria is an amoeba of the Plasmodium group (there are several) – The Vector of malaria is an Anopheles  mosquito – The Host of malaria is, again, a Human, who becomes part of the Reservoir.

~ ~ ~ ~ ~

3) Wasn’t malaria spread around the world by Anopheles  mosquitoes?

Not exactly:


“Malaria occupies a unique place in the annals of history. Over millennia, its victims have included Neolithic dwellers, early Chinese and Greeks, princes and paupers. In the 20th century alone, malaria claimed between 150 million and 300 million lives, accounting for 2 to 5 percent of all deaths (Carter and Mendis, 2002). Although its chief sufferers today are the poor of sub-Saharan Africa, Asia, the Amazon basin, and other tropical regions, 40 percent of the world’s population still lives in areas where malaria is transmitted.”

“Malaria’s probable arrival in Rome in the first century AD was a turning point in European history. From the African rain forest, the disease most likely traveled down the Nile to the Mediterranean, then spread east to the Fertile Crescent, and north to Greece. Greek traders and colonists brought it to Italy. From there, Roman soldiers and merchants would ultimately carry it as far north as England and Denmark (Karlen, 1995).”

“For the next 2,000 years, wherever Europe harbored crowded settlements and standing water, malaria flourished, rendering people seasonally ill, and chronically weak and apathetic. “

From : “Saving Lives, Buying Time:  Economics of Malaria Drugs in an Age of Resistance”

Malaria, historically, has been spread by human movements – humans who harbor the malarial parasites and humans who inadvertently spread the mosquitos that transmit malaria to new locales.

4)  But isn’t malaria eliminated by eliminating Anopheles  mosquitoes?

No, not exactly.  Maybe not at all.  Here’s a map of malaria deaths in the United States in 1870:

Malaria deaths as far north as Michigan, above Chicago, and even some in Vermont.

When was it eliminated?

With this blow-up, we see that malaria wasn’t eliminated in the United States in some areas until as late as 1965.  How do we eliminate malaria?  Kill all the mosquitoes?


The Anopheles quadrimaculatus mosquito is found today in a wide range of east of the Rocky Mountains, but malaria has been totally eliminated. 

How?  By quarantining humans who contract malaria until their blood is free of the parasites.  Humans are the reservoir of malaria, without malarial humans, the mosquitoes have nothing to spread. 

Note:  Occassionally, travelers return to the United States having contracted malaria in the Caribbean or Africa or other malarial areas.  Once they are identified, they are treated in a hospital with anti-malarials.  Malaria is a “nationally notifiable disease” which means doctors and hospitals are required/encouraged to report cases to the CDC.

5)  In areas that are prone to outbreaks of mosquito transmitted diseases, and there are several, tracking mosquito problem areas and spraying for mosquitoes is an important public health effort.  Outbreaks are often traced back to ”lapsed control programmes” — failure to maintain mosquito spraying programs by states, counties, and municipalities.  Activists and lack of funds are the two most common reasons that spraying is discontinued.

Bottom Lines:

1.  Humans, not mosquitoes, are the reservoir of malaria.  Humans sick with malaria spread malaria.  Historically, human trade, exploration and military movements are responsible for spreading malaria worldwide. Mosquitoes are just the vector which moves malaria from one sick human to another (sometimes many).

2.  Malaria is eliminated by treating humans and preventing malarial humans from being bitten by mosquitoes, who would then spread the disease.

3.  Claims that small expansions or changes in habitat size or location of various Anopheles mosquito species are a “new threat” to African populations that might somehow, after centuries, be  “unprepared to cope with the disease” are unfounded and alarmist. 

# # # # #

Author’s Comment:

This is not the first time I have written about malaria and mosquito vectored diseases here.

I spent a day and a half on this essay — Apoorva Mandavilli at the Times writes one story every couple of weeks.   Maybe she has another job that I don’t know about.  But maybe she could have researched the history of malaria and determined that the study did not uncover yet another threat to humanity.

Mandavilli does at least include this caveat paragraph: “Some mosquito movement may also be because of changes in land use, the availability of food or a side effect of people migrating to higher elevations because of climate change, experts said. Still, disease-bearing mosquitoes are of serious concern in areas where people and institutions are unprepared.”  Or rapidly increasing African populations that just need somewhere to farm and live.

Thanks for reading.

# # # # #

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February 18, 2023 10:43 pm

Very interesting.

michael hart
Reply to  Bob
February 19, 2023 7:16 am

Yes. Late last century I attended an interesting presentation, about Malaria, as a grad student. I asked the question about whether human malarial transmission depended just on humans or other species, and received no satisfactory reply.

The other interesting part of his talk was about an anti-malarial drug that Glaxo had developed. It was stellar. Total removal of disease. No development of resistance. A complete winner that knocked it out of the park.
But, here comes the but. It made the patient photo-sensitive. Photo-toxicity meant it was abandoned.

Frankly, I would be happy to live in a dark cave for a couple of weeks if it cured me of Malaria but maybe it can’t be managed in most places. C’est la vie.

Reply to  michael hart
February 19, 2023 9:27 am

It’s too bad horse paste is so deadly.

Rich Davis
Reply to  Bob
February 19, 2023 7:45 am

Yes, great job Kip.

Typical of the Malthusians to feign concern for human life. But their “solution” isn’t better malaria eradication efforts. It’s to eliminate reliable, affordable energy and modern agriculture. Yeah, that’s the ticket. That’ll save lives!

Allan MacRae
Reply to  Bob
February 20, 2023 12:04 pm

I believe this is the true story on the increase in malaria – caused by the ban on DDT:

“My hypothesis is that ’Radical Greens are the Great Killers of Our Age’. Here is some of the supporting evidence.”
“In the 20th Century, socialists Stalin, Hitler and Mao caused the deaths of over 200 million people, mostly their own citizens. Lesser killers like Pol Pot and the many tin-pot dictators of South America and Africa killed and destroyed the lives of many more.

Modern Green Death probably started with the 1972-2002 effective ban of DDT, which caused global deaths from malaria to increase from about 1 million to almost two million per year. Most of these deaths were children under five in sub-Saharan Africa – just babies for Christ’s sake!”
– February 1, 2019

Reply to  Allan MacRae
February 20, 2023 12:29 pm

Your hypothesis.

Steve Milloy and countless others would like a word.

Allan MacRae
Reply to  Charles Rotter
February 20, 2023 2:26 pm

Allan MacRae, April 14, 2019
The banning of DDT from ~1972 to 2002 caused the malaria deaths of tens of millions of children under five years of age, and sickened and killed many more adults and children.
Not just my hypothesis – this from Steve Milloy in 2013:
Premium Times reports:
Also, the South African representative reiterated that it is important for all African leaders to eliminate malaria in Africa, thus, queried why DDT comes under attack annually whenever it is raised as a means of eradicating malaria.
“If we stop using it, we are sentencing our people to death. Every other continent used DDT to eradicate malaria, so why is our turn
different in Africa?”
He said that within five years, South African had a 600 per cent increase in malaria rate from 1996 when the country stopped using DDT.
Also this from the Institute of Economic Affairs, 2001
Richard Tren and Roger Bate 1May2001

February 18, 2023 10:44 pm

St Petersberg 1930s millions affected ?

February 18, 2023 11:00 pm

Thanks Kip. I had a reason to start looking for a fresh version of the malaria story. The reason was, getting that blank look recently when I said something like “people don’t get malaria from mosquitos. It’s the other way round”. I recall the advice in PNG, “Make sure you take your chloroquine dose when you are away, but don’t forget that it is notifiable in most places where it is no longer endemic, so if you do go down with it, you are in a whole heap of trouble because they could be all over you for weeks, might not understand anything about chloroquine-resistant strains and what the alternatives should be.” There were accounts of friends smuggling the right stuff in, victims climbing out of windows or being smuggled out themselves, with borrowed white coats and headgear to get away.

Rich Davis
Reply to  martinc19
February 19, 2023 7:54 am

What a Trumpy thing to say! Are you promoting deadly dangerous hydrochloroquine?

What’s apparently needed here is to get Tony Fauci on the job. Maybe he and Pfizer can come up with something less effective and 10,000 times more expensive to not save any surplus darkies dying of malaria. Or better yet maybe give them heart failure?

Plus…why are they not all masked up?

February 18, 2023 11:02 pm

If only there was some way of controlling malaria-spreading mosquitos

DDT has been banned globally for every use except fighting disease because of its environmental impacts and fears for human health.

WHO says there is no health risk, and DDT should rank with bednets and drugs as a tool for combating malaria, which kills more than one million each year.

“The scientific and programmatic evidence clearly supports this reassessment,” said Dr Anarfi Asamoa-Baah, WHO assistant director-general for HIV/AIDS, TB and Malaria.

“Indoor residual spraying is useful to quickly reduce the number of infections caused by malaria-carrying mosquitoes; it has proven to be just as cost effective as other malaria prevention measures, and DDT presents no health risk when used properly.”Teams of sprayers typically visit endemic areas once a year, spraying the chemical on the inside walls of houses; mosquitoes landing there absorb it and die.

“Of the dozen insecticides WHO has approved as safe for house spraying, the most effective is DDT,” said Arata Kochi, director of the WHO’s Global Malaria Programme.

Ron Long
Reply to  Redge
February 19, 2023 2:55 am

Good addition of discussing DDT and malaria/mosquitos, Redge, however, that knock on your door is probably the ghost of Rachel Carson (ask her to autograph her book Silent Spring?).

Rich Davis
Reply to  Ron Long
February 19, 2023 7:38 am

Another fake crisis invented by the Malthusians to put an end to something that supports human life. If Rachel Carson has a ghost knocking on anyone’s door, it must be coming up from the depths of hell. Her activism is arguably responsible for far more deaths than Hitler.

Without doing a lot of research, it appears that about 8 million people died of malaria in the 90s, 7 million in the 00s, 6 million in the 10s, and around 600k per year at present. I’d guess from that at least 8 million in each of the decades of the 80s and 70s. So let’s say 40 million since 1970.

Ben Vorlich
February 19, 2023 12:02 am

The UK is heading for a return of the Ague.
Recreating wetlands, aka bogs with standing water, reintroduction of beavers more standing water. That coupled with an uncontrolled influx of people from areas where malaria is endemic means it’s just a matter of time. The rest of Europe has the same issues.
The Rewilding wetland creation is another green good idea with only positive outcomes. Like more wild swimmers becoming infected with waterborne diseases UK doctors have never seen.
Not that I think these things are all bad, far from it, but there is a downside to everything and ignoring that is foolish

Reply to  Ben Vorlich
February 19, 2023 1:40 am

Oh, the horrors of unknown infections. Think of the chealdrin! Gotta stop all this Wilding, even if it saves just one life!

Not that I think these things are all bad, far from it, but there is a downside to everything and ignoring that is foolish

Not that I think these things are all bad, far from it, but there is a downside consequence to everything and ignoring that being ignorant is foolish dangerous.
There, edited all the Bolshevikian out of it.

Rich Davis
Reply to  cilo
February 19, 2023 9:10 am

Huh, Cilo?
This comment makes no sense at all. If you’re criticizing Ben’s comments as being “Bolshevist”, then it only follows that you’re a Malthusian who advocates more malaria and seeing people mauled by wolves.

It’s the Malthusians who advocate a zero-human-impact ideal. Re-wilding and all that rot.

Bolsheviks were famous for measuring success through five year plans and ever increasing industrial output. They brought us air you can cut with a knife in East Germany and a Chernobyl dead zone. But now they pretend to care about Mother Gaia when actually all they care about is defeating capitalism.

Reply to  Rich Davis
February 19, 2023 8:52 pm

Language is powerful magic. The reason that reasonable people keep losing the argument against the misanthropes, is because we use language to covey information, They use it to convey emotions. They succeed doubly by placing every subject on an emotional footing.
Thusly, Mr. Davis, I point you to the two (hopefully) very different approaches to the same subject; the Bolshevik nanny state that has to protect every single life, even if thousands have to die for it, versus a world where people are allowed, no, required, to think for themselves.

Rich Davis
Reply to  cilo
February 20, 2023 3:57 am

Words have meaning. You (mis-) deploy “Bolshevik” as others abuse the term “fascist”. When both become synonyms for Orwellian “double-plus ungood” neither conveys any useful meaning. If you oppose the nanny state, then refer to the nanny state. Don’t confuse your prose with anachronistic references that imply meanings that are not relevant. Or do whatever you damn well please, but know that you fail at communication.

I am a big fan of liberty and opponent of government meddling, by the way.

Reply to  Rich Davis
February 20, 2023 4:37 am

Those are, indeed, two polarities; Fascism came into being in answer to Bolshevism. Look up the meaning and origin of the word. Originally the specific political term was ‘fascistic’. Fascism helps to conserve culture, but beyond fierce patriotism, what do they offer?
I’ll grant them their continued success as one of three most terrible curses the Bolshevik throws at anyone who disagrees with their divine privilege.
Such a nice, juicy swearword. I especially like the glow of ignorance in their eyes, while their little fists clench in rage: Ffashhuzt! There’s magic in words; in 1984 Smith’s only friend had the job of shortening the dictionary…

Rich Davis
Reply to  cilo
February 20, 2023 12:42 pm

So there we definitely part company. Fascism invented by the socialist Mussolini and made more virulent by the national socialist Hitler is a kissing cousin of Bolshevism.

Bolsheviks were in theory internationalist and as you say, fascists were nationalists. But both were totalitarians. (Everything within the state, no room for independent civic institutions). Both were socialists, with no real protection of property rights, no inherent individual rights.

Leninism was really a fig leaf of international lip service covering traditional Russian nationalism. As such it was little more than Russian fascism pretending not to be an empire, protesting against the very “imperialism” that it practiced with an iron fist.

The two polarities are classical liberalism (liberty party with individual rights and free markets) vs socialism/communism. Fascism and Communism are like earth and moon vs liberalism which is Alpha Centauri or maybe Andromeda.

Reply to  Rich Davis
February 21, 2023 12:27 am

And now we proceed to rape the term ‘socialism’.
Step aside from the emotions, they are blinding you to true history. They give you six million distractions to prevent you from asking:
“Yes, but how did socialism turn a war-ravaged country with severe poverty into the “…best place to live in all Europe…” with work for everyone, in less than a decade?”
This is not the forum to ask why they got burned alive for their trouble.
But I beseech you to go dust off your dictionary…

Tombstone Gabby
Reply to  Ben Vorlich
February 19, 2023 4:26 pm

G’Day Ben,

“The UK is heading for a return of the Ague.”

You got that right. Oliver Cromwell, 1599 – 1658, died of/with malaria.

February 19, 2023 1:23 am

Mandavilli does at least include this caveat paragraph:

…mosquito movement … because of changes in land use, … food … people migrating to higher elevations because of climate change, experts said.

Caveat my cavarse! She still got that cold blade of climate change in there, plus a whole heap o’ Hexpurt.
Sometimes, only sometimes, malaria comes as far south as Pretoria. Once again climastrologists confuse weather for climate. Mosquitos are sensitive to atmospheric conditions, like humidity, turbulence…

Peta of Newark
February 19, 2023 1:26 am

Malaria: It’s like chronic Vitamin A deficiency, aligned with a Zinc deficiency, has followed us around for ‘quite a long time’
Add in babies getting poor quality colostrum, or even none at all, from their mothers within 2 hours of birth isn’t helping either – or perfect lack of understanding of Vitamin C

and we think we can ‘sort the climate’

February 19, 2023 9:12 am

You would think that science journalists have been carefully trained to research the topics they write about, especially in high-profile media outlets such as the New York Times.

The average science journalist seems grossly inadequate to me and it has been that way for quite some time. What I see written in the articles posted here is generally of a much higher standard than what one reads in the general media.

And I don’t just mean in the quality of the research into the subject being reported, but also in the lucid presentation of the facts and their implications and in presenting varying views on a subject.

Krishna Gans
February 19, 2023 9:27 am

Isn’t there even a “retreat” of malaria ?


Decline in Malaria in Soviet Russia

February 19, 2023 9:39 am

Not this again. Jolly old England had malaria. Siberia had malaria.

Reply to  Kip Hansen
February 19, 2023 1:55 pm

Prior to being allowed ashore from USS Kennedy to visit the Wimpy’s in Mombasa, Kenya we had to take big red anti-malaria pills for weeks in advance. They worked I guess I didn’t get malaria.

February 19, 2023 9:53 am

If they had spent 1/8th of what they have spent on “green energy”, Malaria could be practically irradicated worldwide.

1982 just outside Monrovia, Liberia. I was part of an SF MTT tasked to follow up on the NCO development course for the Liberian Army that a previous SF MTT had established.

Before going we two medics scoured the DoD system for medications and sterilized medical procedure packs about to go out of date that had been turned in for destruction or go out of service. We crammed a small CONEX full of all the medical stuff we had acquired.

Though our task as medics was only to see to the health and welfare of our SF teammates and the Liberian trainees, we did all we could to stock up to treat the trainees families an any others that we had the supplies and capability to take care of.

Afterall, we had been trained as “physician substitutes” and probably had more training than your average physician in the US in the diagnosis, treatment, and preventative medicine relating to parasitic diseases and other conditions and diseases commonly found in the “third world” and you better bet we were aching to put into practice what we had been trained to do!

So, with excellent help from the Army Physicians Assistant attached to the US Embassy, we set up a clinic and worked it in the available hours we had outside of covering our designated mission.

Malaria was by far the #1 serious disease we had to deal with and a lot of our patients were infants and young children. Their mothers would bring them to us caked in dried mud. The local Shaman having told them to cover their child in mud when the spiked a fever.

We also dealt with various trauma, skin conditions, dental problems, etc. But one day we saw a young man that showed all the signs of having a hemorrhagic fever and did not have the ability to do the lab necessary to determine what it was. Ebola was of course our major fear and we instituted full isolation and PPE procedures dealing with him. The PA arranged for him to be transported to a Christian Missionary hospital. They diagnosed it as Yellow Fever.

We had one supplementary mission that popped up while there. A Christain missionary pilot had gone down out in the bush. We trucked out as far as we could go by vehicle and walked out about 20 kilometers and to the crash site. He was dead and had been for three days. We wrapped his remains up in ponchos and strung it up on a pole and carried the remains out. Had to change off frequently because of the smell and puked quite a bit. When you smell that smell of human corruption you never ever forget it! Nothing like it.

Reply to  Kip Hansen
February 19, 2023 1:21 pm

I wish all Americans could see how it is to live on the edge of survival. We ended up having to spread CS powder on the stuff in our garbage pit, which also held medical waste, to keep the women from coming in at night and rummaging through our garbage.

Reply to  rah
February 19, 2023 10:55 pm

A Good Boy would have separated the hazardous stuff to protect the scavengers.
But as Kip says…

Reply to  cilo
February 20, 2023 10:06 am

It would all be burned off periodically. The CS powder did the trick. Besides we medics were doing what we could for them on our own time. Easy to judge when you’re not there.

Jack Belk
February 19, 2023 2:27 pm

Maybe they should consider the banning of DDT as a factor?
We can’t do anything about the ‘climate’, but we CAN apply bug spray!

Crispin in Val Quentin but really in Kigali
February 19, 2023 3:46 pm

Thanks for this, Kip.

I love studies that claim “6.5m altitude change” with an uncertainty of 40m.

One country where such a study might show “something” Eswatini (formerly Swaziland). Malaria is only prevalent in the lowveld which is about 700 ft below the surrounding Lubombo and Middleveld areas. If there was a 6.5m change, the cases would be showing up at the periphery.

Of course you can get malaria in Manzini (at 2000 ft) , and such cases are traced to people living near you – often gardeners – who come from much further east where many people spend their lives infected. A mozzie bites them then flies 100 ft and bites you. Even in Johannesburg at 4500 ft people get malaria in this manner. The reservoir is, as you say, people.

The real reservoir is people and monkeys in the lowveld who resident there. The mozzies are all over the place, but the reservoirs are not. In southern Mozambique there was control over malaria under the Portuguese due to effective (and dangerous) aerial night spraying runs. That stopped 40 years ago.

John McKeon
February 19, 2023 8:16 pm

I just want to clarify that Malaria is NOT transmitted among humans when they spit on each other? Thanks.

If anyone is interested, JAMA Volume 73 number 5 documents an excellent experiment by the US Navy wherein they could NOT infect uninfected test patients with the spittle, blood, mucous or several other concoctions of bodily fluids patients infected with the Spanish Flu. But that was the Spanish corona virus pandemic of a hundred years ago. Things must have been different back then. These days if you so much as get on an airplane that has an infected person on board, two or three of you are sure to become ill. (August 1918 or 19 was the pub date of that JAMA article).

Last edited 1 month ago by John McKeon
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