Malaria is the major public health problem in sub-Saharan Africa, including Ethiopia. Almost half of the Bale Zone's surface area is at risk for malaria. The objective of this study was to analyze the impact of climate variability on the malaria outbreak in Delomena District and recommend control and preventive measures. Meteorological variables (monthly total rainfall, average relative humidity, and mean maximum and minimum temperature) and malaria case data from 2013 to 2022 were used to analyze correlation and regression using SPSS 20v software. The results indicated that the monthly peak of malaria incidence in the Delomena district occurred in June (11 cases), 2021, a year after the main rainy season, while the lowest malaria incidence occurred in January (0 cases), following a short rainy season. Furthermore, the Spearman correlation analysis showed that monthly mean rainfall, relative humidity, and mean minimum temperature had a positive correlation with malaria occurrence but a negative correlation with mean maximum temperature. Also, the negative binomial regression model indicates that, by 1 mm and% increase, both monthly total rainfalls (0.9%) and average relative humidity (3%) at three- and two-month lagged effects were the most significant for malaria occurrence in the study area, respectively, but mean maximum temperature at zero-month lagged effect was negative. However, the mean minimum temperature has an insignificant effect on malaria incidence for all lags. The study concludes that malaria incidences in the last ten years seem to have a significant association and effect with meteorological variables. To reduce malaria outbreaks in the study area, local government and district health experts should promote early warning systems and climate-informed malaria control strategies.
| Published in | Science Discovery Health (Volume 1, Issue 1) |
| DOI | 10.11648/j.sdh.20260101.14 |
| Page(s) | 25-37 |
| Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
| Copyright |
Copyright © The Author(s), 2026. Published by Science Publishing Group |
Climate Variability, Delomena, Malaria
Malaria Case | Total RF (mm) | Ave.RH (%) | Tmax (°C) | Tmin (°C) | |
|---|---|---|---|---|---|
Malaria Case | 1.000 | ||||
Totat RF (mm) | 0.140 | 1.000 | |||
Ave.RH (%) | .480** | .403** | 1.000 | ||
Tmax (°C) | -.464** | -.323** | -.577** | 1.000 | |
Tmin (°C) | .228* | .550** | .350** | -.351** | 1.000 |
Malaria Case | Total RF (mm) | Ave.RH (%) | Tmax (°C) | Tmin (°C) | |
|---|---|---|---|---|---|
Malaria Case | 1.000 | ||||
Totat RF (mm) | .501** | 1.000 | |||
Ave.RH (%) | .469** | .392** | 1.000 | ||
Tmax (°C) | -.323** | -.318** | -.575** | 1.000 | |
Tmin (°C) | .248** | .541** | .339** | -.351** | 1.000 |
Malaria Case | Totat RF (mm) | Ave.RH (%) | Tmax (°C) | Tmin (°C) | |
|---|---|---|---|---|---|
Malaria case | 1.000 | ||||
Totat RF (mm) | .598** | 1.000 | |||
Ave.RH (%) | .379** | .350** | 1.000 | ||
Tmax (°C) | -.206* | -.257** | -.601** | 1.000 | |
Tmin (°C) | .304** | .552** | .364** | -.429** | 1.000 |
Malaria Case | TotatRF (mm) | Ave.RH (%) | Tmax (°C) | Tmin (°C) | |
|---|---|---|---|---|---|
Malaria case | 1.000 | ||||
Totat RF (mm) | .563** | 1.000 | |||
Ave.RH (%) | .257** | .318** | 1.000 | ||
Tmax (°C) | -.222* | -.350** | -.683** | 1.000 | |
Tmin (°C) | .302** | .473** | .288** | -.446** | 1.000 |
Malaria Case | Totat RF (mm) | Ave. | Tmax (°C) | Tmin (°C) | |
|---|---|---|---|---|---|
RH (%) | |||||
Malaria case | 1.000 | ||||
Totat RF (mm) | .437** | 1.000 | |||
Ave.RH (%) | 0.157 | .288** | 1.000 | ||
Tmax (°C) | 0.018 | -.217* | -.661** | 1.000 | |
Tmin (°C) | .184* | .480** | .311** | -.439** | 1.000 |
Parameter | B | Std. Error | Hypothesis Test | Exp (B) | ||
|---|---|---|---|---|---|---|
Wald Chi-Square | Df | Sig. | ||||
(Intercept) | 5.028 | 3.2044 | 2.462 | 1 | .117 | 152.573 |
TotatRF mm | -.001 | .0014 | .739 | 1 | .390 | .999 |
Ave.RH | .022 | .0114 | 3.785 | 1 | .052 | 1.022 |
Tmax°C | -.209 | .0804 | 6.760 | 1 | .009 | .811 |
Tmin°C | .035 | .0863 | .160 | 1 | .689 | 1.035 |
Parameter | B | Std. Error | Hypothesis Test | Exp (B) | ||
|---|---|---|---|---|---|---|
Wald Chi-Square | Df | Sig. | ||||
(Intercept) | 2.704 | 3.3350 | .657 | 1 | .417 | 14.942 |
Totat R.Fmm | .004 | .0013 | 7.768 | 1 | .005 | 1.004 |
Ave. RH | .026 | .0124 | 4.242 | 1 | .039 | 1.026 |
Tmax°C | -.107 | .0829 | 1.672 | 1 | .196 | .898 |
Tmin°C | -.050 | .0880 | .324 | 1 | .569 | .951 |
Parameter | B | Std. Error | Hypothesis Test | Exp (B) | ||
|---|---|---|---|---|---|---|
Wald Chi-Square | Df | Sig. | ||||
(Intercept) | -1.136 | 3.9997 | .081 | 1 | .776 | .321 |
Totat RF mm | .007 | .0018 | 14.308 | 1 | .000 | 1.007 |
Ave. RH | .029 | .0147 | 3.933 | 1 | .047 | 1.030 |
Tmax°C | .005 | .0943 | .002 | 1 | .961 | 1.005 |
Tmin°C | -.047 | .1085 | .188 | 1 | .664 | .954 |
Parameter | B | Std. Error | Hypothesis Test | Exp (B) | ||
|---|---|---|---|---|---|---|
Wald Chi-Square | Df | Sig. | ||||
(Intercept) | -3.277 | 4.4926 | .532 | 1 | .466 | .038 |
TotatRFmm | .009 | .0024 | 13.009 | 1 | .000 | 1.009 |
Ave.RH | .023 | .0157 | 2.147 | 1 | .143 | 1.023 |
Tmax°C | .081 | .1033 | .616 | 1 | .433 | 1.084 |
Tmin°C | -.042 | .1229 | .115 | 1 | .735 | .959 |
Parameter | B | Std. Error | Hypothesis Test | Exp (B) | ||
|---|---|---|---|---|---|---|
Wald Chi-Square | Df | Sig. | ||||
(Intercept) | -5.743 | 4.9414 | 1.351 | 1 | .245 | .003 |
Totat RF mm | .009 | .0031 | 9.318 | 1 | .002 | 1.009 |
Ave. RH | .026 | .0165 | 2.519 | 1 | .112 | 1.026 |
Tmax°C | .176 | .1138 | 2.380 | 1 | .123 | 1.192 |
Tmin°C | -.076 | .1332 | .324 | 1 | .569 | .927 |
EMI | Ethiopia Meteorology Institute |
GLM | General Linear Model |
SPSS | Statistical Package for Social Science |
WHO | World Health Organization |
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APA Style
Zegeye, M. E. (2026). Effects of Climate Variability on Malaria Outbreak in Delomenna District, Bale Zone, Ethiopia. Science Discovery Health, 1(1), 25-37. https://doi.org/10.11648/j.sdh.20260101.14
ACS Style
Zegeye, M. E. Effects of Climate Variability on Malaria Outbreak in Delomenna District, Bale Zone, Ethiopia. Sci. Discov. Health 2026, 1(1), 25-37. doi: 10.11648/j.sdh.20260101.14
@article{10.11648/j.sdh.20260101.14,
author = {Million Ejara Zegeye},
title = {Effects of Climate Variability on Malaria Outbreak in Delomenna District, Bale Zone, Ethiopia},
journal = {Science Discovery Health},
volume = {1},
number = {1},
pages = {25-37},
doi = {10.11648/j.sdh.20260101.14},
url = {https://doi.org/10.11648/j.sdh.20260101.14},
eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.sdh.20260101.14},
abstract = {Malaria is the major public health problem in sub-Saharan Africa, including Ethiopia. Almost half of the Bale Zone's surface area is at risk for malaria. The objective of this study was to analyze the impact of climate variability on the malaria outbreak in Delomena District and recommend control and preventive measures. Meteorological variables (monthly total rainfall, average relative humidity, and mean maximum and minimum temperature) and malaria case data from 2013 to 2022 were used to analyze correlation and regression using SPSS 20v software. The results indicated that the monthly peak of malaria incidence in the Delomena district occurred in June (11 cases), 2021, a year after the main rainy season, while the lowest malaria incidence occurred in January (0 cases), following a short rainy season. Furthermore, the Spearman correlation analysis showed that monthly mean rainfall, relative humidity, and mean minimum temperature had a positive correlation with malaria occurrence but a negative correlation with mean maximum temperature. Also, the negative binomial regression model indicates that, by 1 mm and% increase, both monthly total rainfalls (0.9%) and average relative humidity (3%) at three- and two-month lagged effects were the most significant for malaria occurrence in the study area, respectively, but mean maximum temperature at zero-month lagged effect was negative. However, the mean minimum temperature has an insignificant effect on malaria incidence for all lags. The study concludes that malaria incidences in the last ten years seem to have a significant association and effect with meteorological variables. To reduce malaria outbreaks in the study area, local government and district health experts should promote early warning systems and climate-informed malaria control strategies.},
year = {2026}
}
TY - JOUR T1 - Effects of Climate Variability on Malaria Outbreak in Delomenna District, Bale Zone, Ethiopia AU - Million Ejara Zegeye Y1 - 2026/03/09 PY - 2026 N1 - https://doi.org/10.11648/j.sdh.20260101.14 DO - 10.11648/j.sdh.20260101.14 T2 - Science Discovery Health JF - Science Discovery Health JO - Science Discovery Health SP - 25 EP - 37 PB - Science Publishing Group UR - https://doi.org/10.11648/j.sdh.20260101.14 AB - Malaria is the major public health problem in sub-Saharan Africa, including Ethiopia. Almost half of the Bale Zone's surface area is at risk for malaria. The objective of this study was to analyze the impact of climate variability on the malaria outbreak in Delomena District and recommend control and preventive measures. Meteorological variables (monthly total rainfall, average relative humidity, and mean maximum and minimum temperature) and malaria case data from 2013 to 2022 were used to analyze correlation and regression using SPSS 20v software. The results indicated that the monthly peak of malaria incidence in the Delomena district occurred in June (11 cases), 2021, a year after the main rainy season, while the lowest malaria incidence occurred in January (0 cases), following a short rainy season. Furthermore, the Spearman correlation analysis showed that monthly mean rainfall, relative humidity, and mean minimum temperature had a positive correlation with malaria occurrence but a negative correlation with mean maximum temperature. Also, the negative binomial regression model indicates that, by 1 mm and% increase, both monthly total rainfalls (0.9%) and average relative humidity (3%) at three- and two-month lagged effects were the most significant for malaria occurrence in the study area, respectively, but mean maximum temperature at zero-month lagged effect was negative. However, the mean minimum temperature has an insignificant effect on malaria incidence for all lags. The study concludes that malaria incidences in the last ten years seem to have a significant association and effect with meteorological variables. To reduce malaria outbreaks in the study area, local government and district health experts should promote early warning systems and climate-informed malaria control strategies. VL - 1 IS - 1 ER -