Using infective mosquitoes to challenge monkeys with Plasmodium knowlesi in malaria vaccine studies

Malaria Journal

Table 2 The effect on survival of adding methyparaben to mosquito feed

	Exp 1a	Exp 1b	Exp 2	Exp 3a	Exp 3b	Exp 3c	Exp 3d	Exp 3e	Exp 3f
Mosquito species		dirus X	dirus X	crascens	dirus	dirus X	dirus	dirus	dirus X
Mosquito age at feed	5 days	8 days	5 days	5 days	5 days	5 days	5 days	5 days	5 days
Monkey donor parasitaemia	12%	12%	1.30%	5.50%	5.50%	5.50%	0.30%	0% (control)	0% (control)
% surviving fed sugar only (# replicate cups)	53% (4)	88% (4)	87% (4)	36% (1)	41% (2)	22% (1)	64% (1)	88% (1)	24% (1)
% surviving fed sugar + MPB (# replicate cups)	91% (6)	45% (2)	81% (14)	20% (1)	29% (2)	0% (1)	41% (1)	49% (1)	2% (1)
	p < 0.001	p = 0.04	p = 0.15	p = .03			NA	p = .18

Methylparaben (MPB) was added to the sugar solution used for feeding mosquitoes starting the day they were infected with P. knowlesi. Mosquitoes from the same batch were maintained on sugar solution without MPB. Experiments 1, 2 and 3 were on different dates, and have been subdivided by mosquito species and donor monkey. In some experiments, there were several replicate cups of mosquitoes for each feeding group. Sugar solutions on cages were changed daily. Percentage surviving is the mean from each cup to day 14. P-values were calculated as described in Methods section. For experiment 3d, there were only 2 cups and no statistical test could be done. MPB only improved survival in one of nine sub-experiments.

ISSN: 1475-2875