Background
Methods
Ethical considerations
Study sites
Breeding site mapping
Adult mosquito collection
Species identification and determination of kdr status
Determination of sporozoite rates
Malaria infection prevalence in Conakry
Statistical analysis
Results
Distribution of potential mosquito breeding sites in Conakry
Habitat characteristic | Dry season | Rainy season | ||||
---|---|---|---|---|---|---|
Breeding site |
Culex
|
Anopheles
| Breeding site |
Culex
|
Anopheles
| |
Gutter | 20 (48.8) | 20 (100) | 0 (0) | 19 (38) | 17 (89.5) | 2 (10.5) |
Stretch of ocean | 8 (19.5) | 8 (100) | 0 (0) | 3 (6) | 3 (100) | 0 (0) |
Irrigated rice fields | 3 (7.3) | 3 (100) | 0 (0) | 5 (10) | 4 (80) | 5 (100) |
Pools of water | 4 (9.8) | 4 (100) | 3 (80) | 7 (14) | 4 (57.1) | 3 (42.9) |
Water tanks | 3 (7.3) | 3 (100) | 0 (0) | 7 (14) | 7 (100) | 2 (28.6) |
Septic tanks | 3 (7.3) | 3 (100) | 0 (0) | 5 (9.4) | 4 (80) | 0 (0) |
Tyres | 0 (0) | 0 (0) | 0 (0) | 3 (5.7) | 2 (66.7) | 0 (0) |
Containers | 0 (0) | 0 (0) | 0 (0) | 4 (7.5) | 2 (50) | 1 (25) |
Total | 41 | 41 (100) | 3 (7.3) | 53 | 44 (83) | 13 (24.5) |
Habitat characteristics of larval breeding sites
Habitat characteristics |
Culex
|
Anopheles
| Pupae | ||||||
---|---|---|---|---|---|---|---|---|---|
ORa
| 95 % CI |
P value | ORa
| 95 % CI |
P value | ORa
| 95 % CI |
P value | |
Season | |||||||||
Dry | 13 | (1.6–104.1) | 0.016 | 0.27 | (0.07–1.03) | 0.05 | 25.4 | (5.6–116.4) | <0.001 |
Rainy | 3.1 | (1.7–5.8) | <0.001 | 0.29 | (0.15–0.56) | <0.001 | 0.77 | (0.44–0.32) | 0.338 |
Turbidity | |||||||||
Clear | 0.18 | (0.05–0.70) | 0.014 | 1 | 0.19 | (0.07–0.47) | <0.001 | ||
Turbid | 16 | (5–51.4) | <0.001 | 0.53 | (0.29–1.00) | 0.05 | 4.7 | (2.3–9.6) | <0.001 |
Water movement | |||||||||
Stagnant | 12 | (3.32–43.42) | <0.001 | 3.28 | (0.39–26.93) | 0.27 | 13.5 | (3.5–52.3) | <0.001 |
Flowing | 1 | (0.37–2.66) | 0.796 | 0.07 | (0.01–0.50) | 0.009 | 0.23 | (0.06–0.81) | 0.022 |
Sunlight | |||||||||
Sunlight | 1.28 | (0.36–4.57) | 0.699 | 1 | 1.04 | (0.39–2.81) | 0.931 | ||
Shaded | 4.8 | (1.6–14) | 0.005 | 0.27 | (0.15–0.47) | <0.001 | 1.87 | (0.79–4.42) | 0.151 |
Habitat | |||||||||
Stretch of sea | 0.39 | (0.08–1.99) | 0.259 | 1 | 0.92 | (0.20–4.16) | 0.913 | ||
Irrigated rice field | 1.03 | (0.10–10.23) | 0.980 | 30.8 | (4.1–232) | 0.001 | 0.57 | (0.12–2.85) | 0.498 |
Pool of water | 0.39 | (0.08–1.99) | 0.071 | 15.4 | (2.4–98.3) | 0.004 | 0.41 | (0.10–1.66) | 0.030 |
Water tank | 1 | 4.62 | (0.56–37.91) | 0.154 | 0.52 | (0.12–2.22) | 0.375 | ||
Sceptic tank | 1.03 | (0.10–10.23) | 0.980 | 1 | 1.03 | (0.18–5.8) | 0.970 | ||
Tyre | 1 | 1 | 0.17 | (0.01–2.11) | 0.169 | ||||
Container | 0.44 | (0.04–5.11) | 0.513 | 6.17 | (0.43–89.34) | 0.182 | 1 | ||
Gutter | 6.8 | (2.7–17.4) | <0.001 | 0.05 | (0.01–0.22) | <0.001 | 2.9 | (1.41–5.95) | 0.004 |
Adult mosquito fauna in Conakry
Distribution of mosquitoes in Conakry
Site of collection |
Anopheles gambiae s.l.
|
Culex spp. | Total of mosquitoes | ||||||
---|---|---|---|---|---|---|---|---|---|
ETC | PSC | Total (CI) | ETC | PSC | Total (CI) | ETC | PSC | Total (CI) | |
Matoto | |||||||||
Tombolia | 0 | 0 | 0 (0) | 8.43 | 13.85 | 22.28 (13.18–31.39) | 8.43 | 13.85 | 22.28 (13.18–31.39) |
Gbessia | 0 | 0 | 0 (0) | 9.27 | 11.44 | 20.71 (7.99–32.43) | 9.28 | 11.44 | 20.72 (8.01–32.44) |
Bonagui | 0 | 0 | 0 (0) | 2.91 | 10.90 | 13.81 (7.53–20.1) | 2.93 | 10.90 | 13.83 (7.56–20.11) |
Lassanaya | 0.07 | 0.03 | 0.10 (0–0.25) | 3.19 | 5.49 | 8.68 (3.01–15.24) | 3.27 | 5.51 | 8.78 (2.19–15.37) |
Matam | |||||||||
Boussoura | 0.05 | 0 | 0.05 (0–0.13) | 5.68 | 23.05 | 28.73 (10.35–47.13) | 5.75 | 23.05 | 28.8 (10.37–47.24) |
Bonfi | 0 | 0 | 0 (0) | 3.55 | 13.04 | 16.59 (2.18–31.55) | 3.55 | 13.04 | 16.59 (2.18–28.80) |
Mafanko | 0 | 0 | 0 (0) | 4.37 | 5.69 | 10.06 (3.5–16.62) | 4.42 | 5.75 | 10.17 (3.62–16.72) |
Ratoma | |||||||||
Taouya | 0.04 | 0 | 0.04 (0–0.09) | 5.72 | 17.92 | 23.64 (12.43–34.82) | 5.78 | 17.94 | 23.72 (12.53–34.91) |
Dar es Alaam | 0 | 0.04 | 0.04 (0–0.13) | 4.87 | 12.68 | 17.55 (5.36–29.73) | 4.87 | 12.72 | 17.59 (5.41–29.76) |
Sonfonia I | 0.79 | 1 | 1.79 (0.53–3.02) | 2.67 | 10.875 | 13.55 (6.66–20.44) | 3.59 | 11.90 | 15.49 (8.25–22.73) |
Sonfonia II | 0.21 | 0.21 | 0.42 (0.08–0.76) | 3.69 | 8.71 | 12.40 (4.62–20.19) | 3.91 | 8.92 | 12.83 (4.92–20.75) |
Dixinn | |||||||||
Belle vue | 0.03 | 0 | 0.03 (0–0.06) | 11.10 | 23.71 | 34.81 (11.38–58.25) | 11.16 | 23.74 | 34.9 (11.5–58.28) |
Camayenne | 0 | 0 | 0 (0) | 3.26 | 11.64 | 14.9 (9.98–19.83) | 3.26 | 11.64 | 14.9 (9.98–19.83) |
Kaloum | |||||||||
Tombo | 0.01 | 0.03 | 0.04 (0–0.12) | 2.75 | 39.54 | 42.29 (16.73–67.85) | 2.76 | 39.57 | 42.33 (16.79–67.86) |
Coronthie | 0.04 | 0 | 0.04 (0–0.09) | 1.72 | 4.44 | 6.16 (2.77–9.54) | 1.76 | 4.44 | 6.20 (2.82–9.58) |
Variation of mosquito density
Composition of feeding status and variation of Culex and Anopheles mosquitoes parity rate
Characterization of Anopheles
Distribution of the kdr mutation
District |
An. gambiae molecular form | Total |
Kdr genotype | |||
---|---|---|---|---|---|---|
RR | RS | SS | (%) of resistant (R and RS) | |||
Matoto |
An. gambiae s.s.
| 4 | 4 | 0 | 0 | 4 (100) |
Matam |
An. coluzzii
| 1 | 0 | 0 | 1 | 1 (50) |
An. gambiae s.s.
| 1 | 0 | 0 | 1 | 0 (0) | |
Kaloum |
An. coluzzii
| 1 | 0 | 0 | 1 | 1 (100) |
An. gambiae s.s.
| 4 | 2 | 0 | 0 | 2 (50) | |
Ratoma |
An. coluzzii
| 84 | 28 | 28 | 25 | 56 (60.2) |
An. gambiae s.s.
| 7 | 2 | 2 | 1 | 4 (57.1) | |
Conakry |
An. coluzzii
| 89 | 30 | 28 | 27 | 58 (65.2) |
An. gambiae s.s.
| 13 | 7 | 2 | 2 | 9 (81.8) | |
Total | 102 | 37 | 30 | 29 | 67 (65.7) |