Airflow attenuation and bed net utilization: observations from Africa and Asia

Malaria Journal

Table 1 airflow measurements in 20 houses in Thailand, Philippines, The Gambia and Tanzania using a bed net with a mesh of 220 holes per square inch

	#	Bed net	Median airspeed outside net	Median airspeed inside net	Attenuation of airflow	Median temp^†(21:00 to 6:00)⁰ C	Median relative humidity^†(21:00 to 6:00)
Thailand	1	On/off	0.14	0.06	57%	25.5	43%
	2	On/off	0.11	0.06	45%	24.5	55%
	3	On/off	0.15	0.1	33%	24.2	67%
Philippines	4	On/off	0.14	0.06	57%	25.4	89%
	5	Inside/outside	0.06	0.03	50%	25.5	92%
	6	Inside/outside	0.08	0.03	63%	25.9	92%
	7	Inside/outside	0.11	0.08	27%	24.7	92%
	8	Inside/outside	0.09	0.03	67%	25.1	92%
	9	Inside/outside	0.09	0.06	33%	27.1	90%
The Gambia	10	Inside/outside	0.07	0.02	71%	26.3	66%
	11	Inside/outside	0.07	0.02	71%	28.4	62%
	12	Inside/outside	0.09	0.03	67%	25.1	58%
	13	Inside/outside	0.06	0.03	50%	27.0	50%
	14	Inside/outside	0.05	0.03	40%	28.1	56%
	15	Inside/outside	0.09	0.03	67%	26.0	61%
	16	Inside/outside	0.09	0.03	67%	24.3	57%
Tanzania	17	Inside/outside	0.06	0.04	33%	26.8	73%
	18	Inside/outside	0.12	0.06	50%	27.7	69%
	19	Inside/outside	0.14	0.08	43%	27.0	73%
	20	Inside/outside	0.08	0.02	75%	28.0	69%
Overall			0.09	0.04	50%	26.0	70%

†No significant difference in temperature or humidity was detected inside and outside the net. (Note that the measurements were not conducted during the hottest period of the year); * p-value <0.001 comparing airspeed inside and outside bed net (Mann–Whitney two-sample statistic or Wilcoxon matched-pairs signed-ranks test).

ISSN: 1475-2875