Introduction
Materials and methods
Study sites’ description
Survey study on water management and prevalence of waterborne diseases
Water sampling procedure
Sampling site | Longitude | Latitude | Well depth (m) | Colour | No users | Construction year | |
---|---|---|---|---|---|---|---|
Dry season | Rainy season | ||||||
FS1 | 15° 17′ 11.2″ | 4° 24′ 18.5″ | 22 | – | Clear | ± 1200 | 2019 |
FS2 | 15° 17′ 09.3″ | 4° 24′ 35.2″ | 35 | – | Clear | ± 2500 | 2018 |
FK1 | 15° 22′ 58.0″ | 4° 26′ 37.3″ | 40 | – | Clear | ± 2500 | 2015 |
FK2 | 15° 22′ 03.7″ | 4° 26′ 36.1″ | 28 | – | Clear | ± 1500 | 2016 |
FK3 | 15° 22′ 07.1″ | 4° 26′ 48.1″ | 30 | – | Clear | ± 1000 | 2014 |
PS1 | 15° 17′ 05.5″ | 4° 24′ 1.2″ | 3 | 1 | Soft | ± 200 | 2016 |
PS2 | 15° 17′ 04.1″ | 4° 24′ 03.8″ | 3 | 1.5 | Clear | ± 300 | 2017 |
PS3 | 15° 17′ 00.8″ | 4° 24′ 07.4″ | 5 | 3 | Clear | ± 300 | 2016 |
PS4 | 15° 16′ 59.2″ | 4° 24′ 12.4″ | 3 | 2 | Soft | ± 100 | 2016 |
PS5 | 15° 17′ 01.5″ | 4° 24′ 27.4″ | 7 | 5 | Clear | ± 400 | 2017 |
PS6 | 15° 17′ 01.9″ | 4° 24′ 29.0″ | 3 | 2 | Clear | ± 200 | 2016 |
PS7 | 15° 17′ 02.0″ | 4° 24′ 29.4″ | 3 | 2 | Clear | ± 150 | 2017 |
PK1 | 15° 22′ 01.8″ | 4° 26′ 39.8″ | 5 | 5 | Clear | ± 50 | 2015 |
PK2 | 15° 22′ 01.7″ | 4° 26′ 39.6″ | 10 | 9 | Soft | ± 80 | 2018 |
PK3 | 15° 22′ 00.3″ | 4° 26′ 37.8″ | 4 | 4 | Soft | ± 100 | 2016 |
PK4 | 15° 22′ 04.4″ | 4° 26′ 52.2″ | 8 | 7 | Clear | ± 80 | 2013 |
PK5 | 15° 22′ 04.4″ | 4° 26′ 48.1″ | 6 | 4 | Clear | ± 200 | 2019 |
SK1 | 15° 22′ 26.6″ | 4° 26′ 04.1″ | 1 | 1 | Clear | + 500 | 2017 |
SK2 | 15° 22′ 19.1″ | 4° 26′ 56.6″ | 1 | 1 | Clear | ± 500 | 2017 |
SK3 | 15° 22′ 19.2″ | 4° 26′ 56.1″ | 0.5 | 1 | Clear | ± 300 | 2018 |
SK4 | 15° 22′ 08.7″ | 4° 26′ 54.1″ | 0.8 | 1 | Soft | ± 150 | 2018 |
Physicochemical parameter analysis
Faecal indicator bacteria analysis in water samples
Statistical analysis
Results and discussion
Survey of water source management
Epidemiologic survey associated to waterborne diseases
Diseases | 2016 | 2017 | 2018 | 2019 | ||||
---|---|---|---|---|---|---|---|---|
Ngafani | Esanga | Ngafani | Esanga | Ngafani | Esanga | Ngafani | Esanga | |
Typhoid fever | 38 | 6 | ND | ND | 782 | 4 | 880 | 8 |
Paludism | 6 | 16 | 1117 | 8 | 325 | 30 | 147 | 68 |
Amoebic dysentery | 2 | 9 | 20 | 28 | 20 | 13 | 9 | 26 |
Filariasis | 4 | 3 | ND | 7 | ND | 13 | ND | 7 |
Gastroenteritis disorders | 2 | 21 | 1 | 26 | 6 | 18 | 10 | 10 |
Cholera | 1 | 1 | 0 | 1 | 0 | 6 | 2 | 3 |
Diarrhoea | 98 | 300 | 269 | 279 | 86 | 311 | 64 | 314 |
Diseases | 0–11 months | 1–4 years | 5–14 years | More than 15 years | Average |
---|---|---|---|---|---|
Paludism | 35.11 | 39.79 | 41.03 | 52.66 | 42.15 |
Typhoid fever | 1.77 | 2.33 | 6.55 | 8.85 | 4.88 |
Amebic dysentery | 1.04 | 2.85 | 3.12 | 5.82 | 3.21 |
Gastroenteritis disorders | 1.32 | 0.99 | 0.74 | 0.89 | 0.99 |
Filariasis | 2.18 | 1.94 | 0.75 | 3.45 | 2.08 |
Diarrhoea | 3.50 | 2.97 | 2.15 | 2.32 | 2.74 |
Water physicochemical characteristics
Sampling sites | T (°C) | pH | EC (μs cm−1) | O2 (mg L−1) | ||||
---|---|---|---|---|---|---|---|---|
Dry | Rainy | Dry | Rainy | Dry | Rainy | Dry | Rainy | |
FS1 | 24.6 | 26.4 | 6.1 | 5.9 | 135 | 94 | 2.3 | 1.9 |
FS2 | 24.1 | 25.8 | 6.4 | 6.2 | 325 | 112 | 3.5 | 2.3 |
FK1 | 26.5 | 28.1 | 5.6 | 6.3 | 264 | 197 | 4.1 | 5.1 |
FK2 | 26.8 | 28.5 | 6.1 | 4.6 | 158 | 178 | 5.0 | 6.8 |
FK3 | 26.2 | 28.0 | 5.3 | 5.6 | 138 | 182 | 4.7 | 6.2 |
PS1 | 26.5 | 27.3 | 6.1 | 5.8 | 342 | 85 | 2.7 | 2.9 |
PS2 | 25.8 | 27.9 | 6.5 | 5.7 | 258 | 132 | 3.2 | 3.5 |
PS3 | 24.9 | 26.7 | 6.8 | 6.2 | 105 | 74 | 1.5 | 2.3 |
PS4 | 26.1 | 26.3 | 6.9 | 5.7 | 470 | 123 | 3.0 | 2.7 |
PS5 | 25.3 | 27.5 | 5.9 | 6.4 | 85 | 24 | 1.1 | 2.2 |
PS6 | 24.8 | 27.7 | 6.5 | 5.8 | 189 | 135 | 3.4 | 2.9 |
PS7 | 26.3 | 26.6 | 6.7 | 5.9 | 435 | 289 | 2.9 | 3.1 |
PK1 | 23.9 | 27.3 | 6.1 | 7.4 | 563 | 82 | 3.1 | 2.4 |
PK2 | 26.6 | 27.6 | 5.9 | 7.8 | 206 | 85 | 2.2 | 3.0 |
PK3 | 26.5 | 27.4 | 6.3 | 6.7 | 704 | 98 | 2.5 | 3.3 |
PK4 | 25.2 | 28.0 | 6.6 | 5.3 | 48 | 88 | 1.8 | 2.9 |
PK5 | 24.6 | 28.1 | 5.6 | 5.6 | 304 | 66 | 3.6 | 3.2 |
SK1 | 26.4 | 27.8 | 5.7 | 6.6 | 115 | 74 | 1.9 | 1.4 |
SK2 | 26.9 | 27.2 | 5.2 | 6.7 | 363 | 82 | 3.7 | 3.1 |
SK3 | 26.5 | 27.1 | 5.5 | 7.2 | 458 | 72 | 4.9 | 3.0 |
SK4 | 24.3 | 28.8 | 5.3 | 7.0 | 62 | 78 | 2.5 | 3.2 |
WHO regulationa | 12–25 | 6.5–9.5 | 200–800 | 4–6 |
Sampling sites | Na+ (mg L−1) | K+ (mg L−1) | PO43−(mg L−1) | SO42− (mg L−1) | NO3−(mg L−1) | NO2−(mg L−1) | ||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Dry | Rainy | Dry | Rainy | Dry | Rainy | Dry | Rainy | Dry | Rainy | Dry | Rainy | |
FS1 | 92.61 | 36.42 | 5.46 | 2.37 | 0.09 | 0.01 | 103.24 | 78.66 | 6.33 | 8.52 | 0.01 | 0.01 |
FS2 | 78.56 | 58.90 | 4.88 | 2.19 | 0.83 | 0.07 | 94.32 | 19.45 | 1.32 | 12.40 | 0.01 | 0.01 |
FK1 | 98.34 | 60.11 | 7.53 | 2.34 | 0.71 | 0.35 | 132.12 | 77.66 | 7.32 | 10.52 | 0.01 | 0.01 |
FK2 | 103.20 | 51.14 | 8.52 | 3.17 | 0.88 | 0.62 | 215.32 | 141.27 | 5.41 | 9.06 | 0.01 | 0.01 |
FK3 | 99.6 | 52.8 | 8.59 | 6.4 | 0.56 | 0.37 | 145.89 | 85.9 | 6.25 | 11.3 | 0.02 | 0.02 |
PS1 | 28.64 | 17.44 | 8.50 | 6.11 | 0.01 | 0.02 | 128.15 | 31.01 | 25.48 | 72.17 | 0.02 | 0.09 |
PS2 | 19.77 | 11.50 | 4.23 | 2.89 | 0.12 | 0.03 | 24.75 | 12.43 | 9.55 | 16.24 | 0.01 | 0.04 |
PS3 | 31.01 | 24.35 | 2.89 | 3.56 | 1.04 | 0.07 | 9.07 | 6.06 | 9.98 | 10.12 | 0.02 | 0.05 |
PS4 | 27.22 | 12.84 | 6.11 | 7.55 | 0.94 | 0.02 | 12.02 | 4.75 | 21.52 | 65.80 | 0.05 | 0.15 |
PS5 | 44.10 | 31.50 | 4.99 | 2.93 | 0.45 | 0.02 | 7.88 | 6.55 | 12.56 | 24.58 | 0.01 | 0.01 |
PS6 | 9.96 | 10.11 | 7.37 | 3.19 | 0.78 | 0.04 | 11.23 | 7.88 | 28.01 | 31.04 | 0.06 | 0.09 |
PS7 | 52.44 | 42.31 | 10.47 | 7.51 | 1.03 | 0.02 | 20.05 | 12.92 | 1.38 | 9.78 | 0.01 | 0.05 |
PK1 | 39.86 | 23.44 | 2.92 | 0.66 | 0.38 | 0.01 | 77.77 | 23.44 | 38.09 | 74.14 | 0.03 | 0.99 |
PK2 | 7.91 | 2.14 | 3.64 | 1.04 | 0.54 | 0.33 | 139.44 | 101.03 | 43.61 | 83.11 | 0.77 | 1.02 |
PK3 | 78.81 | 69.56 | 3.14 | 1.19 | 0.95 | 0.99 | 134.11 | 76.15 | 29.16 | 35.09 | 0.01 | 0.03 |
PK4 | 10.22 | 8.77 | 2.06 | 0.99 | 0.09 | 0.01 | 111.09 | 45.22 | 32.53 | 75.12 | 0.02 | 0.07 |
PK5 | 32.73 | 21.17 | 3.71 | 1.24 | 0.71 | 0.03 | 13.65 | 8.91 | 7.90 | 28.41 | 0.02 | 0.07 |
SK1 | 53.41 | 32.11 | 8.32 | 4.22 | 0.32 | 0.21 | 49.33 | 22.45 | 2.30 | 7.45 | 0.01 | 0.01 |
SK2 | 18.76 | 6.58 | 2.34 | 0.39 | 0.98 | 0.99 | 200.03 | 64.49 | 47.84 | 68.24 | 0.01 | 0.87 |
SK3 | 27.12 | 3.33 | 6.45 | 2.22 | 0.56 | 0.12 | 99.05 | 45.08 | 4.58 | 10.17 | 0.01 | 0.04 |
SK4 | 22.53 | 9.99 | 3.56 | 1.18 | 1.15 | 0.55 | 88.26 | 42.14 | 31.15 | 59.44 | 0.01 | 0.96 |
WHO regulationa | 10–100 | 15 | ≤ 0.5 | 500 | 50 | 3 |
Microbiological quality of water from wells and springs
Sampling sites | E. coli (CFU ± SD × 102 100 mL−1) | ENT (CFU ± SD × 102 100 mL−1) | TC (CFU ± SD × 103 100 mL−1) | |||
---|---|---|---|---|---|---|
Dry | Rainy | Dry | Rainy | Dry | Rainy | |
Managed wells | ||||||
FS1 | 0 | 0 | 0 | 0 | 0 | 0 |
FS2 | 0.32 ± 0.03 | 0.90 ± 0.35 | 0.48 ± 0.09 | 0.89 ± 0.12 | 0.19 ± 0.04 | 0.38 ± 0.11 |
FK1 | 0 | 0 | 0 | 0 | 0 | 0 |
FK2 | 0 | 0.03 ± 0.00 | 0 | 0.05 ± 0.00 | 0 | 0.09 ± 0.02 |
FK3 | 0 | 0 | 0 | 0 | 0 | 0 |
Unmanaged wells | ||||||
PS1 | 2.21 ± 0.18 | 20.01 ± 1.12 | 9.08 ± 1.31 | 28.01 ± 2.21 | 11.04 ± 1.04 | 35.30 ± 3.51 |
PS2 | 0.03 ± 0.02 | 0.21 ± 0.06 | 0.11 ± 0.09 | 0.98 ± 0.15 | 0.09 ± 0.01 | 0.64 ± 0.05 |
PS3 | 0.41 ± 0.07 | 0.81 ± 0.15 | 0.12 ± 0.03 | 1.12 ± 0.06 | 0.17 ± 0.02 | 0.31 ± 0.05 |
PS4 | 11.21 ± 0.05 | 19.31 ± 1.22 | 22.10 ± 0.51 | 16.11 ± 1.22 | 35.12 ± 3.97 | 79.12 ± 3.77 |
PS5 | 0.09 ± 0.01 | 0.03 ± 0.00 | 0.12 ± 0.08 | 0.19 ± 0.03 | 0.17 ± 0.06 | 0.29 ± 0.07 |
PS6 | 7.03 ± 0.39 | 29.07 ± 8.25 | 8.31 ± 2.51 | 10.52 ± 1.75 | 2.83 ± 0.32 | 14.32 ± 2.13 |
PS7 | 3.11 ± 0.12 | 24.06 ± 3.18 | 6.03 ± 1.15 | 28.13 ± 2.59 | 7.06 ± 1.48 | 13.42 ± 6.04 |
PK1 | 2.43 ± 0.35 | 12.08 ± 0.77 | 3.13 ± 0.77 | 15.18 ± 7.16 | 2.03 ± 0.04 | 17.22 ± 6.12 |
PK2 | 7.33 ± 1.11 | 29.36 ± 2.14 | 6.99 ± 2.01 | 16.10 ± 2.44 | 38.04 ± 2.17 | 79.03 ± 8.33 |
PK3 | 2.63 ± 0.44 | 29.36 ± 2.14 | 1.98 ± 0.22 | 32.08 ± 1.11 | 3.20 ± 0.18 | 19.03 ± 3.33 |
PK4 | 3.55 ± 0.99 | 22.44 ± 3.11 | 3.96 ± 1.02 | 43.10 ± 2.22 | 7.18 ± 0.92 | 14.99 ± 4.15 |
PK5 | 1.42 ± 0.13 | 45.12 ± 3.22 | 1.12 ± 0.25 | 56.29 ± 4.13 | 1.32 ± 0.81 | 24.44 ± 3.11 |
Streams | ||||||
SK1 | 0 | 0.03 ± 0.00 | 0 | 0.08 ± 0.01 | 0 | 0.07 ± 0.02 |
SK2 | 2.55 ± 0.33 | 4.37 ± 1.08 | 2.69 ± 0.47 | 8.15 ± 1.09 | 9.06 ± 1.75 | 10.03 ± 3.37 |
SK3 | 0.06 ± 0.01 | 0.90 ± 0.13 | 0.04 ± 0.00 | 0.78 ± 0.17 | 0.08 ± 0.01 | 0.24 ± 0.01 |
SK4 | 4.32 ± 0.76 | 6.50 ± 0.92 | 3.35 ± 0.18 | 9.88 ± 1.03 | 1.13 ± 0.04 | 7.11 ± 2.13 |
EU/WHOa | 0 | 0 | 0 |
Statistical correlation
T (°C) | pH | EC | O2 | Na+ | K+ | PO43+ | SO42− | NO3− | NO2− | E. coli | ENT | TC | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
T (°C) | − 0.102 | − 0.020 | 0.518 | − 0.130 | − 0.620 | − 0.090 | − 0.186 | 0.103 | 0.175 | 0.077 | 0.125 | − 0.166 | |
pH | − 0.399 | − 0.427 | − 0.332 | − 0.321 | 0.332 | 0.270 | 0.322 | 0.670 | − 0.007 | − 0.139 | 0.206 | ||
EC | 0.555 | 0.388 | 0.388 | − 0.180 | 0.001 | − 0.354 | − 0.259 | 0.005 | − 0.046 | − 0.083 | |||
O2 | 0.362 | − 0.221 | − 0.052 | 0.064 | − 0.196 | − 0.127 | − 0.134 | − 0.120 | − 0.148 | ||||
Na+ | 0.159 | 0.267 | 0.318 | − 0.557 | − 0.464 | − 0.210 | − 0.153 | − 0.384 | |||||
K+ | − 0.341 | − 0.231 | − 0.247 | − 0.459 | − 0.045 | − 0.092 | 0.180 | ||||||
PO43+ | 0.6131 | 0.113 | 0.318 | − 0.067 | − 0.070 | − 0.070 | |||||||
SO42− | − 0.005 | 0.147 | − 0.177 | − 0.191 | − 0.014 | ||||||||
NO3− | 0.706 | 0.450 | 0.451 | 0.679 | |||||||||
NO2− | 0.122 | 0.039 | 0.369 | ||||||||||
E. coli | 0.880 | 0.602 | |||||||||||
ENT | 0.705 |
T (°C) | pH | EC | O2 | Na+ | K+ | PO43+ | SO42− | NO3− | NO2− | E. coli | ENT | TC | |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
T (°C) | − 0.185 | 0.190 | 0.291 | 0.002 | 0.094 | − 0.099 | 0.170 | 0.052 | 0.193 | 0.032 | 0.129 | 0.315 | |
pH | 0.149 | − 0.358 | − 0.120 | 0.120 | 0.014 | − 0.407 | − 0.097 | − 0.027 | 0.338 | 0.433 | 0.233 | ||
EC | 0.271 | 0.056 | 0.000 | 0.102 | 0.067 | 0.121 | − 0.074 | 0.193 | 0.278 | 0.181 | |||
O2 | 0.287 | 0.1591 | 0.044 | 0.197 | − 0.259 | − 0.177 | − 0.157 | − 0.102 | − 0.173 | ||||
Na+ | 0.430 | 0.073 | 0.387 | − 0.551 | − 0.305 | − 0.527 | − 0.413 | − 0.412 | |||||
K+ | − 0.023 | − 0.002 | − 0.524 | − 0.168 | − 0.112 | 0.110 | − 0.089 | ||||||
PO43+ | − 0.008 | 0.009 | − 0.048 | 0.269 | 0.140 | 0.065 | |||||||
SO42− | 0.299 | 0.157 | − 0.192 | − 0.233 | 0.028 | ||||||||
NO3− | 0.692 | 0.593 | 0.353 | 0.635 | |||||||||
NO2− | 0.437 | 0.219 | 0.715 | ||||||||||
E. coli | 0.902 | 0.812 | |||||||||||
ENT | 0.785 | ||||||||||||
TC |