Patients’ demographics
The study enrolled 469 patients who visited outpatient clinics seeking healthcare for febrile illness. Of them, 334 (71.2%) tested positive for malaria, while 135 (28.8%) tested negative. Based on gender the study population included 233 (49.7%) males and 236 (50.3%) females, with age range of 4 months to 87 years. The mean age of the study population was 24.75 ± 19.81 years [95% CI (22.95–26.55)], and the median age was 24 years. The analysis revealed that the highest proportion of malaria cases was among patients aged 5–14 years, while the lowest proportion was among patients aged over 59 years; 35 (7.5%). However, the differences between the age groups were not statistically significant (p-value = 0.214). Meanwhile, based on gender, a slightly higher proportion of females tested positive for malaria compared to males, but again, the difference was not statistically significant (p-value = 0.065). Whereas, a statistically significant difference in malaria diagnosis between the different locations was found; p-value = 0.024. The highest proportion of positive malaria cases was observed in Al Hasahisa; 77 (77.0%), while the lowest proportion was observed in East Al Gazira; 103 (76.9%) (Table 1).
Table 1
distribution of the study patients according to their age group, gender, and location
| Malaria diagnosis | Total | p-value |
Positive | Negative |
Patient age group | | | | |
Less than 1 year | 26 (60.5%) | 17 (39.5%) | 43 (9.2%) | 0.214 |
1–4 years | 30 (65.2%) | 16 (34.8%) | 46 (9.8%) |
5–14 years | 58 (67.4%) | 28 (32.6%) | 86 (18.3%) |
15–59 years | 193 (74.5%) | 66 (25.5%) | 259 (55.2%) |
More than 59 years | 27 (77.1%) | 8 (22.9%) | 35 (7.5%) |
Patient gender | | | | |
Male | 158 (67.8%) | 75 (32.2%) | 233 (49.7%) | 0.065 |
Female | 176 (74.6%) | 60 (25.4%) | 236 (50.3%) |
Patient location | | | | |
Al Hasahisa | 77 (77.0%) | 23 (23.0%) | 100 (21.3%) | 0.024 |
Al Managel | 154 (65.5%) | 81 (34.5%) | 235 (50.1%) |
East Al Gazira | 103 (76.9%) | 31 (23.1%) | 134 (28.6%) |
Total | 334 (71.2%) | 135 (28.8%) | 469 (100%) | |
Clinical characteristics of the participants and its associations with malaria infection
Concerning the malaria symptoms observed in this study, 246 (73.7%) of the confirmed malaria cases reported fever, while 88 (65.2%) of those who tested negative for malaria have reported fever (p-value = 0.044). However, the odds ratio was 1.130 (95% CI: 0.983–1.298), indicating a positive but not statistically significant association between fever and malaria diagnosis (Spearman Correlation Coefficient − 0.085, p-value 0.067.)
Among the participants who reported not having diarrhea, 245 (73.4%) were positive for malaria while 114 (84.4%) were tested negative (p-value = 0.006). The odds ratio was 0.601 (95% CI: 0.398–0.909), indicating a negatively statistically significant association between the absence of diarrhea and malaria diagnosis (Spearman Correlation Coefficient − 0.119, p-value = 0.010).
Overall, the results show that several symptoms were negatively associated with malaria diagnosis, including headache (Spearman Correlation Coefficient − 0.120, p-value 0.009), vomiting (-0.093, p-value 0.044), abdominal pain (-0.099, p-value 0.032), shivers, (-0.153, p-value < 0.001) anxiety (-0.159, p-value < 0.001), and fatigue (-0.166, p-value < 0.001). However, the associations were not statistically significant for joint pain (-0.046, p-value 0.323) (Table 2).
Table 2
Patients signs and symptoms and their relation with malaria diagnosis
| Malaria diagnosis | Total | OR | 95% Confidence Interval | p-value | Spearman Correlation Coefficient |
Negative | Positive | Lower | Upper | value | p-value |
Fever | | | | | | | | | |
Yes | 88 (65.2%) | 246 (73.7%) | 334 (71.2%) | 0.670 | 0.436 | 1.029 | 0.044 | -0.085 | 0.067 |
No | 47 (34.8%) | 88 (26.3%) | 135 (28.8%) |
Headache | | | | | | | | | |
Yes | 61 (45.2%) | 195 (58.4%) | 256 (54.6%) | 0.588 | 0.393 | 0.879 | 0.006 | -0.120 | 0.009 |
No | 74 (54.8%) | 139 (41.6%) | 213 (45.4%) |
Vomiting | | | | | | | | | |
Yes | 40 (29.6%) | 132 (39.5%) | 172 (36.7%) | 0.644 | 0.419 | 0.990 | 0.027 | -0.093 | 0.044 |
No | 95 (70.4%) | 202 (60.5%) | 297 (63.3%) |
Abdominal pain | | | | | | | | | |
Yes | 32 (23.7%) | 113 (33.8%) | 145 (30.9%) | 0.608 | 0.385 | 0.959 | 0.020 | -0.099 | 0.032 |
No | 103 (76.3%) | 221 (66.2%) | 324 (69.1%) |
Diarrhoea | | | | | | | | | |
Yes | 21 (15.6%) | 89 (26.6%) | 110 (23.5%) | 0.507 | 0.300 | 0.857 | 0.006 | -0.119 | 0.010 |
No | 114 (84.4%) | 245 (73.4%) | 359 (76.5%) |
Joint pain | | | | | | | | | |
Yes | 77 (57.0%) | 207 (62.0%) | 284 (60.6%) | 0.815 | 0.543 | 1.223 | 0.187 | -0.046 | 0.323 |
No | 58 (43.0%) | 127 (38.0%) | 185 (39.4%) |
Shivers | | | | | | | | | |
Yes | 33 (24.4%) | 136 (40.7%) | 169 (36.0%) | 0.471 | 0.301 | 0.738 | 0.001 | -0.153 | < 0.001 |
No | 102 (75.6%) | 198 (59.3%) | 300 (64.0%) |
Anxiety | | | | | | | | | |
Yes | 51 (37.8%) | 185 (55.4%) | 236 (50.3%) | 0.489 | 0.325 | 0.736 | 0.001 | -0.153 | < 0.001 |
No | 84 (62.2%) | 149 (44.6%) | 233 (49.7%) |
Fatigue | | | | | | | | | |
Yes | 52 (38.5%) | 190 (56.9%) | 242 (51.6%) | 0.475 | 0.316 | 0.715 | 0.001 | -0.166 | < 0.001 |
No | 83 (61.5%) | 144 (43.1%) | 227 (48.4%) |
Total | 135 (28.8%) | 334 (71.2%) | 469 (100%) | | | | | | |
*OR = Odd Ratio |
The relationship between preventive measures and risk factors of malaria
The relationship between wearing protective clothes and malaria showed that individuals who did not wear protective clothes were more than twice as likely to test positive for malaria compared to those who did wear protective clothes; p-value 0.001. A total of 225 (67.4%) tested positive for malaria, and 110 (81.5%) of those who tested negative did not wear protective clothes, the odds ratio for wearing protective clothes is 2.132 (95%CI [1.305–3.482]). The association of wearing protective clothes with malaria was significantly positively correlated (Spearman Correlation coefficient 0.141, p-value 0.002).
The relationship was also found statistically significant difference for malaria positivity and using of insecticides; presence of trees; and presence of stagnant water, p-values were 0.040, 0.035, and 0.014, respectively. At the same times the odds ratios for those who are not using insecticides, or have trees in or around their houses, and existence of stagnant water were more likely to test positive for malaria; 1.462 (95%CI [0.976–2.19]), 1.479 (95% CI [0.989–2.21]), and 1.621 (95% CI [1.071–2.453]), respectively. However, no statistically significant association was observed for using insecticides (0.085, p-value 0.065), presence of trees (0.088, p-value 0.056), whereas, presence of stagnant water showed a positively statistically significant association with malaria positivity (0.106, p-value 0.022).
The association of using smoke as a repellent, using of bed nets, and closing of windows and doors at night with malaria positivity was neutral did and not show neither significant difference nor significant association (Table 3).
Table 3
relationship of malaria preventive measures and risk factors with malaria patients
| Malaria diagnosis | Total | Odds ratio | 95% Confidence Interval | p-value | Spearman Correlation Coefficient |
| Negative | Positive | Lower | Upper | value | p-value |
Wearing protective clothes | | |
No | 110 (81.5%) | 225 (67.4%) | 335 (71.4%) | 2.132 | 1.305 | 3.482 | 0.001 | 0.141 | 0.002 |
Yes | 25 (18.5%) | 109 (32.6%) | 134 (28.6%) | | | | | | |
Using of mosquito repellants | | |
No | 108 (80.0%) | 252 (75.4%) | 360 (76.8%) | 1.302 | 0.798 | 2.124 | 0.175 | 0.049 | 0.292 |
Yes | 27 (20.0%) | 82 (24.6%) | 109 (23.2%) | | | | | | |
Using of insecticides | | |
No | 79 (58.5%) | 164 (49.1%) | 243 (51.8%) | 1.462 | 0.976 | 2.19 | 0.040 | 0.085 | 0.065 |
Yes | 56 (41.5%) | 170 (50.9%) | 226 (48.2%) | | | | | | |
Presence of trees | | |
No | 75 (55.6%) | 153 (45.8%) | 228 (48.6%) | 1.479 | 0.989 | 2.21 | 0.035 | 0.088 | 0.056 |
Yes | 60 (44.4%) | 181 (54.2%) | 241 (51.4%) | | | | | | |
Presence of stagnant water | | |
No | 88 (65.2%) | 179 (53.6%) | 267 (56.9%) | 1.621 | 1.071 | 2.453 | 0.014 | 0.106 | 0.022 |
Yes | 47 (34.8%) | 155 (46.4%) | 202 (43.1%) | | | | | | |
Using of smoke as repellent | | |
No | 87 (64.4%) | 194 (58.1%) | 281 (59.9%) | 1.308 | 0.865 | 1.979 | 0.121 | 0.059 | 0.204 |
Yes | 48 (35.6%) | 140 (41.9%) | 188 (40.1%) | | | | | | |
Using of bed nets | | |
No | 53 (39.3%) | 139 (41.6%) | 192 (40.9%) | 0.907 | 0.603 | 1.364 | 0.358 | -0.022 | 0.639 |
Yes | 82 (60.7%) | 195 (58.4%) | 277 (59.1%) | | | | | | |
Closing of windows and doors | | |
No | 43 (31.9%) | 101 (30.2%) | 144 (30.7%) | 1.078 | 0.701 | 1.659 | 0.406 | 0.016 | 0.732 |
Yes | 92 (68.1%) | 233 (69.8%) | 325 (69.3%) | | | | | | |
Total | 135 (28.8%) | 334 (71.2%) | 469 (100%) | | | | | | |
The relationship between the different preventative measures and malaria risk factors with malaria infection base on location
According to locality, the relationship between the different preventative measures and malaria diagnosis showed that in Al Hasahisa, among individuals who did not have trees in or around their houses, 84.0% tested positive for malaria. The odds ratio for the presence of trees is 1.377 (95%CI [1.208–1.570]), indicating that individuals who did not have tree near or in their houses are less likely to test positive for malaria compared to those who have trees near or in their houses; p-value 0.010. As well, the association of trees presence with malaria was negatively statistically significant (Spearman Correlation Coefficient − 0.239, p-value 0.017).
The relationship and association between wearing protective clothes, using of mosquito repellants, using of insecticides, presence of stagnant water, using of smoke as a repellent, using of bed nets, and closing windows and doors with malaria in Al Hasahisa did not show any statistically significance (Table 4, Supplementary File 1: Table S1).
Table 4
relationship of malaria preventive measures and risk factors with malaria patients according to their localities
Patient location | Malaria diagnosis | Total | p-value | Odds ratio | 95% Confidence Interval |
Negative | Positive | lower | Upper |
Al Hasahisa | | | | | | |
Wearing protective clothes | | | | | |
No | 0 (0.0%) | 2 (100%) | 2 (2.0%) | 0.591 | 1.307 | 1.171 | 1.458 |
Yes | 23 (23.5%) | 75 (76.5%) | 98 (98.0%) | | | | |
Using of mosquito repellants | | | | | |
No | 4 (12.1%) | 29 (87.9%) | 33 (33.0%) | 0.056 | 0.348 | 0.108 | 1.126 |
Yes | 19 (28.4%) | 48 (71.6%) | 67 (67.0%) | | | | |
Using of insecticides | | | | | |
No | 0 (0.0%) | 6 (100%) | 6 (6.0%) | 0.199 | 1.324 | 1.180 | 1.485 |
Yes | 23 (24.5%) | 71 (75.5%) | 94 (94.0%) | | | | |
Presence of trees | | | | | |
No | 0 (0.0%) | 16 (100%) | 16 (16.0%) | 0.010 | 1.377 | 1.208 | 1.570 |
Yes | 23 (27.4%) | 61 (72.6%) | 84 (84.0%) | | | | |
Presence of stagnant water | | | | | |
No | 0 (0.0%) | 10 (100%) | 10 (10.0%) | 0.063 | 1.343 | 1.190 | 1.516 |
Yes | 23 (25.6%) | 67 (74.4%) | 90 (90.0%) | | | | |
Using of smoke as repellent | | | | | |
No | 3 (15.8%) | 16 (84.2%) | 19 (19.0%) | 0.309 | 0.572 | 0.151 | 2.168 |
Yes | 20 (24.7%) | 61 (75.3%) | 81 (81.0%) | | | | |
Using of bed nets | | | | | |
No | 0 (0.0%) | 4 (100%) | 4 (4.0%) | 0.345 | 1.315 | 1.175 | 1.471 |
Yes | 23 (24.0%) | 73 (76.0%) | 96 (96.0%) | | | | |
Closing windows and doors | | | | | |
No | 0 (0.0%) | 0 (0.0%) | 0 (0.0%) | n.a. | n.a. | n.a. | n.a. |
Yes | | | | | | | |
Total | 23 (23.0%) | 77 (77.0%) | 100 (100%) | | | | |
East Al Gazira | | | | | | |
Wearing protective clothes | | | | | |
No | 31 (25.4%) | 91 (74.6%) | 122 (91.0%) | 0.036 | 0.746 | 0.673 | 0.827 |
Yes | 0 (0.0%) | 12 (100%) | 12 (9.0%) | | | | |
Using of mosquito repellants | | | | | |
No | 28 (26.9%) | 76 (73.1%) | 104 (77.6%) | 0.040 | 3.316 | 0.932 | 11.796 |
Yes | 3 (10.0%) | 27 (90.0%) | 30 (22.4%) | | | | |
Using of insecticides | | | | | |
No | 26 (28.6%) | 65 (71.4%) | 91 (67.9%) | 0.022 | 3.040 | 1.077 | 8.579 |
Yes | 5 (11.6%) | 38 (88.4%) | 43 (32.1%) | | | | |
Presence of trees | | | | | |
No | 26 (29.9%) | 61 (70.1%) | 87 (64.9%) | 0.009 | 3.580 | 1.272 | 10.075 |
Yes | 5 (10.6%) | 42 (89.4%) | 47 (35.1%) | | | | |
Presence of stagnant water | | | | | |
No | 22 (27.2%) | 59 (72.8%) | 81 (60.4%) | 0.123 | 1.823 | 0.765 | 4.344 |
Yes | 9 (17.0%) | 44 (83.0%) | 53 (39.6%) | | | | |
Using of smoke as repellent | | | | | |
No | 21 (28.0%) | 54 (72.0%) | 75 (56.0%) | 0.096 | 1.906 | 0.817 | 4.443 |
Yes | 10 (16.9%) | 49 (83.1%) | 59 (44.0%) | | | | |
Using of bed nets | | | | | |
No | 18 (26.5%) | 50 (73.5%) | 68 (50.7%) | 0.235 | 1.468 | 0.652 | 3.304 |
Yes | 13 (19.7%) | 53 (80.3%) | 66 (49.3%) | | | | |
Closing windows and doors | | | | | |
No | 5 (21.7%) | 18 (78.3%) | 23 (17.2%) | 0.551 | 0.908 | 0.307 | 2.684 |
Yes | 26 (23.4%) | 85 (76.6%) | 111 (82.8%) | | | | |
Total | 31 (23.1%) | 103 (76.9%) | 134 (100%) | | | | |
Al Managel | | | | | | |
Wearing protective clothes | | | | | |
No | 79 (37.4%) | 132 (62.6%) | 211 (89.8%) | 0.002 | 6.583 | 1.507 | 28.751 |
Yes | 2 (8.3%) | 22 (91.7%) | 24 (10.2%) | | | | |
Using of mosquito repellants | | | | | |
No | 76 (34.1%) | 147 (65.9%) | 223 (94.9%) | 0.400 | 0.724 | 0.222 | 2.357 |
Yes | 5 (41.7%) | 7 (58.3%) | 12 (5.1%) | | | | |
Using of insecticides | | | | | |
No | 53 (36.3%) | 93 (63.7%) | 146 (62.1%) | 0.270 | 1.242 | 0.709 | 2.174 |
Yes | 28 (31.5%) | 61 (68.5%) | 89 (37.9%) | | | | |
Presence of trees | | | | | |
No | 49 (39.2%) | 76 (60.8%) | 125 (53.2%) | 0.068 | 1.572 | 0.910 | 2.713 |
Yes | 32 (29.1%) | 78 (70.9%) | 110 (46.8%) | | | | |
Presence of stagnant water | | | | | |
No | 66 (37.5%) | 110 (62.5%) | 176 (74.9%) | 0.061 | 1.760 | 0.909 | 3.408 |
Yes | 15 (25.4%) | 44 (74.6%) | 59 (25.1%) | | | | |
Using of smoke as repellent | | | | | |
No | 63 (33.7%) | 124 (66.3%) | 187 (79.6%) | 0.369 | 0.847 | 0.438 | 1.636 |
Yes | 18 (37.5%) | 30 (62.5%) | 48 (20.4%) | | | | |
Using of bed nets | | | | | |
No | 35 (29.2%) | 85 (70.8%) | 120 (51.1%) | 0.054 | 0.618 | 0.359 | 1.062 |
Yes | 46 (40.0%) | 69 (60.0%) | 115 (48.9%) | | | | |
Closing windows and doors | | | | | |
No | 38 (31.4%) | 83 (68.6%) | 121 (51.5%) | 0.189 | 0.756 | 0.441 | 1.296 |
Yes | 43 (37.7%) | 71 (62.3%) | 114 (48.5%) | | | | |
Total | 81 (34.5%) | 154 (65.5%) | 235 (100%) | | | | |
In East Al Gazira locality, the relationship between malaria and wearing of protective clothing as a preventive measure, among individuals who did not Wearing protective clothes, 74.6% tested positive for malaria, while 25.4% of those who tested negative did not wear protective clothing. Although, the odds ratio was 0.746 (95%CI [0.673–0.827]), this indicates wearing protective clothing in East Al Gezira contribute in reducing the risk of infection; p-value 0.036. The association of wearing protective clothes and malaria was positively statistically significant (Spearman Correlation Coefficient 0.172, p-value 0.047). Also, using of mosquito repellants, using of insecticides, presence of trees was also showing statistically significant relationships with malaria infection; p-values 0.040, 0.022, and 0.009, respectively, but, in terms of association with malaria, only using of insecticides and presence of trees showed positively statistically significant association with malaria (Spearman Correlation Coefficients; 0.188 and 0.218, and p-values 0.033 and 0.011, respectively). However, the odds ratio showed that it is more likely to have malaria infection when not using mosquito repellants; 3.316 (95% CI [0.932–11.796]) or insecticides; 3.040 (95% CI [1.077–8.579]), while more likely to have the infection when trees are near or in the house; 3.580 (95% CI [1.272–10.075]) (Table 4, Supplementary File 1: Table S1)
In Al Managel locality, the relationship between malaria and wearing of protective clothing was the only preventive measure showing positively statistically significant association with malaria (Spearman Correlation Coefficient 0.185, p-values 0.004). Among the individuals who did not wear protective clothes, 62.6% tested positive for malaria, while 37.4% of those who tested negative did not wear protective clothing. The odds ratio was 6.583 (95%CI [1.507–28.751]), this indicates wearing protective clothing in Al Managel contribute significantly in reducing the risk of malaria infection; p-value 0.002 (Table 4, Supplementary File 1: Table S1).
Risk factors associated with malaria
We studied several potential risk factors that might be associated with malaria infection. These potential risk factors include age, gender, no using protective measures such as wearing protective clothing, using mosquito repellents, using insecticides, living near trees and stagnant water, using of smoke as a repellent, bed nets, and closing of windows and doors (Table 5).
Table 5
Logistic regression analysis for estimating malaria preventive and risk factors associated with malaria positive patients
Risk Factors | Beta coefficient | p-value | 95% Confidence Interval |
Lower | Upper |
1–4 years | -0.792 | 0.120 | 0.167 | 1.229 |
5–14 years | -0.588 | 0.247 | 0.205 | 1.503 |
15–59 years | -0.488 | 0.292 | 0.247 | 1.523 |
More than 59 years | -0.143 | 0.737 | 0.375 | 2.001 |
Patient’s gender | -0.331 | 0.106 | 0.481 | 1.073 |
Wearing protective clothes | -0.757 | 0.003 | 0.287 | 0.766 |
Using mosquito repellants | -0.264 | 0.292 | 0.471 | 1.254 |
Using of insecticides | -0.380 | 0.065 | 0.457 | 1.024 |
Presence of trees | -0.391 | 0.056 | 0.452 | 1.011 |
Presence of stagnant water | -0.483 | 0.022 | 0.408 | 0.933 |
Using smoke as a repellent | -0.268 | 0.204 | 0.505 | 1.157 |
Using bed nets | 0.098 | 0.638 | 0.733 | 1.659 |
Closing of windows and doors | -0.075 | 0.732 | 0.603 | 1.427 |
According to the our findings, utilizing protective clothing presents a significant defense against malaria with a negative beta coefficient of -0.757 and a p-value of 0.003. Thus, individuals who wear protective clothes are at a lesser risk of contracting the disease. On a similar note, stagnant water serves as a significant contributing factor for malaria, with a negative beta coefficient of -0.483 and a p-value of 0.022. Consequently, individuals who reside near stagnant water bodies are at a higher risk of contracting malaria.
Other risk factors that showed trend toward significance included the use of insecticides, the presence of trees, and the use of smoke as a repellent (p-values 0.065 and 0.056, respectively). The age group, gender, using mosquito repellants, using smoke as a repellent, using bed nets, and closing of windows and doors at night did not show significant association with malaria risk, with p-values greater than 0.1. Overall, the results suggest that the only protective measures; wearing protective clothing and avoiding areas near stagnant water can be effective in reducing the risk of contracting malaria (Table 5).