Table 2.
Geographical area |
Vector |
Analyzed environmental
factors |
Affected by climate
change |
Changes in prevalence or incidence
due to climate change |
Expansion due to climate
change |
First author (year of
publication) |
|
---|---|---|---|---|---|---|---|
Main findings | |||||||
East [Kenia) | Anopheles spp | Average temperature increase | Yes | Increases | No | 19, | |
An increase of 1ºC has been registered over the last 30 years, which coincides with an increase in malaria outbreaks | |||||||
East [Kenia] | Anopheles spp | Average temperature increase | Uncertain | Uncertain | Uncertain | 17, | |
Parasitary development may be underestimated under cold conditions if only average monthly temperatures are taken into account. On the contrary, under warm weather conditions it may be overestimated | |||||||
East [Kenia] | Anopheles spp | Variations in rainfall patterns, altitude changes | Yes | Decreases | No | 42, | |
Decreasing trends in malaria at both low and high altitudes. Increases in rainfall increment significantly malaria incidence | |||||||
East [Kenia] | Anopheles spp | Average temperature variations | No | Decreases | No | 45, | |
Predicted relative increases in the larvarian development rate due to climate change are smaller since water temperature does not increase | |||||||
East [Kenia] | Anopheles spp | Average temperature increase, variations in diurnal temperature | No | Increases | No | 18, | |
If diurnal temperature range increases, extrinsic incubation period sensitivity decreases. Relative effects of average temperature increases are smaller than predicted if daily temperature fluctuations are taken into account | |||||||
East [Tanzania] | Anopheles gambiae, Anopheles stephensi | Average temperature increase | No | Decreases | No | 44, | |
After mosquito exposure to different temperatures (27ºC optimal temperature, 30ºC and 33ºC future projections] and diurnal variability (0,6–9ºC), it is verified that average temperature increases induce a decrease in oocyte prevalence and intensity and sporozoite prevalence | |||||||
East (Tanzania) | Anopheles spp | Average temperature increase, increased rainfall | Yes | Increases | Uncertain | [32] | |
32–33ºC endemic transmission frame. Effects of rainfall are more unpredictable and difficult to quantify | |||||||
East (Tanzania) | Anopheles spp | Average temperature increase, increased rainfall | Yes | Increases | Yes | [33] | |
Extinction depends more on rainfall than on temperature. Optimal temperature for endemic transmission and progress into previously free zones: 32–33ºC. In 2080, with 4–5ºC increases, Rukwa and Kigoma (near Democratic Republic of Congo). Southern Morogoro, Iringa, Ruvuma and Mtwara near Malawi and Mozambique will be affected | |||||||
East [Kenia, Uganda, Rwanda, Burundi) | Anopheles gambiae | Average temperature increase | Yes | Increases | Yes | 20, | |
Temperature changes significantly amplified by mosquito population dynamics | |||||||
East [Ethiopia] | Anopheles spp | Average temperature increase, increased altitude | Yes | Increases | Yes | 37, | |
Increases in temperature extend spatial distribution to higher altitudes | |||||||
East [Ethiopia, Kenia, Uganda] | Anopheles spp | Average temperature increase, increased rainfall | Yes | Increases | No | 41, | |
Significant changes in climatic variability coincide with increased magnitude and frequency of malaria epidemics since 1989 | |||||||
South, East and West | Anopheles gambiae, Anopheles arabiensis | Average temperature increase | Yes | Increases | Yes | 34, | |
Future malaria suitability will decrease in Western Africa and Sahel due to increases in average annual temperatures and will increase in Eastern and Southern Africa because of 1.5–2.7ºC increases | |||||||
West [Niger, Benin and Mali] | Anopheles gambiae | Average temperature variations, increased rainfall | Uncertain | Increases | Yes | 24, | |
If tropical meteorological data from Benin were applied on the Niger Sahel, mosquito abundance will increase, whereas it may decrease with Malian data | |||||||
Africab | Anopheles spp | Average temperature increase, diminished rainfall | Yes | Increases | Yes | 27, | |
Current occurrence is restricted by deserts and highlands, epidemics in the Sahel and some Highland regions. Future projections show a decrease in most tropical areas in Africa due to increasing temperatures and decreasing annual rainfall. Increasing epidemics in southern Sahel. Increasing intensity in Eastern Africa and Highland areas | |||||||
Africab | Anopheles gambiae | Net effect of climate change | Yes | Uncertain | Yes | 35, | |
All year transmission suitable areas shift from Central and Western Africa to Uganda, Angola, Gabon and Cameroon. High season transmission [4–8 months] expands into Southern Africa and Madagascar | |||||||
Africab | Anopheles gambiae, Anopheles arabiensis | Average temperature increase, variations in summer and Winter rainfall | Yes | Increases | Yes | 39, | |
Shift toward Southern and Eastern Africa. Western and Central Africa might lose suitability for both Anopheles species | |||||||
Africab | Anopheles gambiae, Anopheles arabiensis | Average temperature increase, variations in rainfall patterns | Yes | Increases | Yes | 40, | |
Anopheles gambiae expansion toward Angola, Burundi, Comoro Islands, Ethiopia, Kenia, Malawi, Mali, South Africa, Tanzania, Zambia; and of Anopheles arabiensis toward Angola Botswana, Burundi, Democratic Republic of Congo, Djibouti, Ethiopia, Kenia, Malawi, Namibia, Rwanda, South Africa, Sudan, Swaziland, Gambia, Uganda, Zimbabwe with 2ºC temperature increase in all Africa and changes in rainfall patterns. 0.1ºC increases lead to expansion of Anopheles gambiae toward Angola, Cameroon, Ethiopia, Guinea, Mozambique, Niger, Sierra Leona, South Africa, Uganda, Zambia and Zimbabwe. | |||||||
Worldwidea | Anopheles spp | Net effect of climate change | Yes | Increases | No | 47, | |
Increase in malaria in East African highlands, South Africa, central Angola and the Madagascar plateau. Decreases in tropical areas, including Western Africa. Net increase of suitability and population at risk, but with uncertainties | |||||||
Worldwidea | Anopheles spp | Net effect of climate change, climate trends since 1900 | Yes | Decreases | No | 28, | |
Future effects are smaller than those observed since 1900. Contradiction between observed and predicted effects |
aPredictive models that analyze disease incidence at worldwide level.
bPredictive models that analyze disease incidence throughout the whole African continent.