Sugar-fermenting yeast as an organic source of carbon dioxide to attract the malaria mosquito Anopheles gambiae

Malaria Journal

Table 5 Effect of yeast-produced CO₂ on trap catches during screen house experiments

Treatment	Control	Total number caught		χ²-test	N	Mean % caught (± sem)¹
Treatment	Control	T	C	χ²-test	N	Mean % caught (± sem)¹
no odour	no odour	22	19	P = 0.64	800	5.1 ± 0.7
worn sock	clean sock	288	48	P < 0.001	800	43.1 ± 4.1
yeast CO_{2 (17.5 g)}	no odour	250	16	P < 0.001	800	33.3 ± 5.7
yeast CO_{2 (35 g)}	no odour	251	11	P < 0.001	800	32.8 ± 5.1
yeast CO_{2 (17.5 g)}	ind. CO_{2 (100 ml/min)}	274	190	P < 0.001	800	58.0 ± 7.9
yeast CO_{2 (35 g)}	ind. CO_{2 (250 ml/min)}	326	244	P < 0.001	800	71.3 ± 2.6
yeast CO_{2 (17.5 g)} + worn sock	clean sock	411	13	P < 0.001	800	53.0 ± 12.7
yeast CO_{2 (17.5 g)} + worn sock	worn sock	581	55	P < 0.001	800	79.5 ± 2.5
yeast CO_{2 (17.5 g)} + worn sock	ind. CO_{2 (100 ml/min)} + worn sock	342	265	P = 0.002	800	75.9 ± 1.8
yeast CO_{2 (17.5 g)} 24 h	no odour	132	18	P < 0.001	800	18.8 ± 2.9
yeast CO_{2 (17.5 g)} 24 h	ind. CO_{2 (100 ml/min)}	240	384	P < 0.001	800	78.0 ± 4.7
yeast CO_{2 (17.5 g)} 48 h	no odour	57	41	P = 0.11	800	12.3 ± 1.9
yeast CO_{2 (17.5 g)} 48 h	ind. CO_{2 (100 ml/min)}	30	342	P < 0.001	800	46.5 ± 2.8

Yeast = yeast-produced (either 17.5 g yeast+250 g sugar+2½ L water or 35 g yeast+500 g sugar+2½ L water in each 5 L bottle)
Ind. = industrial (flow rate given in ml/min)
T = treatment
C = control
N = total number of mosquitoes released
¹ Mean percentage caught expressed as the number of female mosquitoes caught in the two MM-X traps together divided by the number of mosquitoes that flew out of the release cage.
Underlined number: significant higher catch (χ²-test, P < 0.05)

ISSN: 1475-2875