Malaria is much less of an issue in Southern Africa than in my current abode in East Africa. But it was a trip to Botswana a few years ago that first drew my attention to this tropical malady. While my destination near Gaborone in the south was not on the malaria map, Kasane in the north and Zimbabwe, to which I intended to travel were. So my travel companion tasked me with getting malaria prophylactics.
My investigation raised my doubts about malaria transmission story and effectiveness of treatments, so I did not get anything. And we did not contract malaria! The East – South difference in the perception of malaria was confirmed after returning to Ireland when the blood transfusion service declined my donation for 12 months because I changed planes at Addis Ababa in Ethiopia!
But a news story in MalariaWorld this week reports increased malaria in Southern Africa. Africa CDC (Centres for disease control) reports that up to week 23, of 2025, Zimbabwe has reported 111,998 cases and 310 deaths (case fatality rate [CFR]: 0.27%) as compared to 29,031 cases with 49 deaths (CFR: 0.17%) in the same period in 2024. Botswana in same period has recorded 2,223 cases and 11 deaths, compared to 218 cases and no deaths in same period in 2024. Namibia also had a significant rise in malaria cases, with over 89,959 cases and 146 deaths reported since November 2024.
So why the increase which is a reverse of recent trends? Dr Memory Mapfumo, an epidemiologist at the Africa CDC blamed prolonged rains that fuelled mosquito breeding, and activities like gold panning, fishing and artisanal mining are exposing more individuals to risk, especially during peak mosquito activity hours. The belief in infectious disease including mosquito transmission of malaria is core belief of Africa CDC, like its well-known US namesake.
But what if malaria is caused by toxins? I wrote about connection to mining before, and last week visited an artisanal goldmine in Kenya that clearly exposes workers to additional health risks such as finely ground mineral material and various toxic chemicals.
Africa CDC reports low usage of mosquito nets, but this does not explain an increase in cases. Movement of people is also used as an explanation of increase, but it is not clear how. Flooding in Okavango (picture from my visit) increasing mosquito habitat was blamed for increase in Botswana. The possible effect of flooding on drinking water quality was not considered.
In Eswatini 20% of cases were among farmers, many involved in illegal farming activities. These farmers often work at night leaving them exposed to mosquito bites. Or is increase in illness influenced by the effects on health of a disrupted body clock?
It is important to be concerned about the increase of cases of malaria in Southern Africa. However, much as Africa CDC tries, it is difficult to explain the increase in case number by concentrating on the supposed link to mosquitos and ignoring other factors that affect health.