The impact of global warming on insect-borne diseases and on highland malaria in particular remains controversial. Temperature is known to influence transmission intensity through its effects on the population growth of the mosquito vector and on pathogen development within the vector. Spatiotemporal data at a regional scale in highlands of Colombia and Ethiopia supplied an opportunity to examine how the spatial distribution of the disease changes with the interannual variability of temperature. We provide evidence for an increase in the altitude of malaria distribution in warmer years, which implies that climate change will, without mitigation, result in an increase of the malaria burden in the densely populated highlands of Africa and South America.
Altitudinal cumulative distribution of malaria cases (Debre Zeit)
Yearly cumulative distribution of malaria cases (P. falciparum) with altitude for each year from 1994 to 2004 for the study region in Ethiopia. Cases are aggregated for the transmission season as explained in the Supplement of the paper.
CumulatedCases_Ethiopia.csv
Altitudinal cumulative distribution of malaria cases (Antioquia)
Yearly cumulative distribution of malaria cases (P. falciparum) with altitude from 1990 to 2006 for the transmission season in the study region of Antioquia, Colombia. See section on "epidemiological data' in Supplementary Information of the paper.
CumulatedCases_Colombia.csv
Time series of mean temperatures (Ethiopia)
Monthly time series of mean temperatures. Four meteorological stations in Ethiopia situated in close proximity to the study areas were selected. Monthly averages of daily minimum and maximum temperature data for the stations in Ethiopia were obtained from the Ethiopian National Meteorological Agency (NMA).
The four climate stations in Ethiopia (namely Addis Ababa (Bole), Addis Ababa (Obs), Adama and Debre Zeit) were selected based on their proximity to Debre Zeit town (within 50 km) and their high correlation with Debre Zeit’s station readings. Missing data were filled by the lagged 5 year climatology (average for the same month in the preceding five years). Data for the four stations were then averaged for the two variables, and monthly mean temperature were generated by taking the average of the monthly minimum and maximum temperature.
MeanMonthlyTemperature_Ethiopia.csv
Total malaria cases during transmission season (Debre Zeit)
The reported (falciparum and vivax) malaria cases aggregated for the study region and for the epidemic season for each year between 1980 and 2004.
TotalCases_MainSeason_Ethiopia.csv
Discretized malaria cases (Debre Zeit)
The monthly epidemiological data (falciparum malaria cases) from 159 kebeles in Ethiopia were discretized into a set of finite levels by putting all zeros in the lowest level and then dividing the remaining data into observed quantiles of cases per capita. Three levels are considered here: no cases (0), cases below the median (1), and cases above the median (2). These format of the data are used in the grouping algorithm applied in Figure 1 to identify groups of administrative units (kebeles) with similar temporal dynamics. See Method and associated references in the Supplementary Information of the paper.
DiscretizedCases_Ethiopia.csv
Total malaria cases during transmission season (Anori, Colombia)
Yearly time series of reported cases for (falciparum and vivax) malaria in the epidemic season from 1980 to 2006 for the municipality of Anori in Colombia.
TotalCases_MainSeason_Anori.csv
Time series of mean temperatures (Colombia)
A monthly time series of mean temperatures was obtained by averaging data from a number of meteorological stations. Nine meteorological stations in Colombia, situated in close proximity to the study areas were selected. Monthly mean temperature for the stations in Colombia was obtained from the Colombian Institute for Hydrology and Meteorology (IDEAM).
Five stations in the East and four in the West were selected after removing those with inconsistent and sparse data, and restricting them to be within 500 and 2500 masl. We filled the gaps in the climate time series with the 10 year climatology (average for the same month in the preceding 10 or 15 years depending on data availability).
MeanMonthlyTemperature_Colombia.csv
Discretized malaria cases (Antioquia)
The monthly epidemiological data (falciparum malaria cases) from 77 municipalities were discretized into a set of finite levels by putting all zeros in the lowest level and then dividing the remaining data into observed quantiles of cases per capita. Three levels are considered here: no cases (0), cases below the median (1), and cases above the median (2). These format of the data are used in the grouping algorithm applied in Figure 1 to identify groups of municipalities with similar temporal dynamics. See Method and associated references in the Supplementary Information of the paper.
DiscretizedCases_Colombia.csv
