Health and social care services research

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Browsing Health and social care services research by Subject "Keywords Spatial Activity Index"

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    Optimal Efficacy in Mosquito-Host Interaction Inhibition by 35-60 kHz Animal Sounds for Malaria Control
    (Published online at http://journal.sapub.org/biophysics, 2024-11-14) Mang’are P. A., Makatiani J. K., Ndiritu F. G., Rotich S. K.
    The haematophagous mated female Anopheles gambiae sensu stricto, a malaria vector, continues to develop resistance to synthetic insecticides thus threatening its control. Studies on negative phonotaxis response in mosquitoes showed that the electronic mosquito repellent (EMR) (40-55 kHz) sound, Odorrana tormota (35-60 kHz) sound, and winded-EMR sound yielded 68.99%, 45.88%, and 60.70% repellency respectively, proving the feasibility of using non-pollutant sounds in mosquito control. However, studies with O. tormota sounds were rudimental and didn’t observe protocols for mosquito rearing standard operation procedures (SOPs) and World Health Organisation (WHO) guidelines for efficacy testing of spatial repellents. Also, phonotactic inhibition by natural sounds of Delphinapterus leucas and male A. gambiae s.s had not been studied. This research, therefore, determined spatial activity index (SAI) and protection index (PI) of mated female A.gambiae s.s evoked by 35-60 kHz sounds of O. tormota, D. leucas, and male A. gambiae s.s in adherence to mosquito rearing SOPs and WHO guidelines. Mosquitoes were reared in Kenya Medical Research Institute (KEMRI) Entomology laboratories observing KEMRI SOPs protocols. Sounds of a hundred 3-5-day-old male A. gambiae s.s were recorded using an Avisoft recorder whereas the sounds of O. tormota and D. leucas were acquired through donations. Mosquito exhibited adverse abnormal composure, low flights, antennae erection, open wings, and extension of legs during the bioassays under the treatment with the sound of O. tormota. The data obtained were analyzed using Avisoft SASLab and Raven Pro software. Mean SAI evoked by O. tormota, male A. gambiae s.s, and D. leucas were 0.142, 0.318, and 0.206 respectively, indicating negative phonotaxis. The PI elicited by O. tormota was 80.06% exceeding male A. gambiae s.s and D. leucas by 1.65% and 8.24% respectively. Frequency modulated, constant frequency, and pulsating sound of O. tormota showed mean bandwidth (mean entire; 13.95 kHz), maximum frequency (mean entire; 41.61 kHz), maximum energy (8.02 Pa2s), entropy (2.87 bits), delta power (24.10 dB), average power (55.60 dB), maximum power frequency (38.09 kHz) and maximum power (75.90 dB). This study provides new acoustic parameters and an effective repellent recommended for mosquito control.