Hand-carried Thermal Fogger Standard Evaluation amongs network of the Vector-Borne Disease Control Center 8.2 Loei province

Abstract

This cross-sectional descriptive study aimed to determine the quantity of hand-carried thermal foggers meeting standard criteria at the Vector-Borne Disease Control Center 8.2 in Loei province, Thailand. The sample group consisted of 42 hand-carried thermal fogger machines from 5districts, 1 sub-districts each, selected randomly through a multi-stage sampling process. The study evaluated four aspects: 1) Chemical liquid flow rate, 2) Pipe end temperature, 3) Volume Median Diameter (VMD) of the chemical droplet, and 4) Span value. It was conducted between November 2022 and May 2023, and descriptive statistics were applied for data analysis. The results revealed that 14 network agencies provided 42 hand-carried thermal fogger machines for evaluation. The majority were from the best fogger brand, accounting for 57.15 percent, with a lifespan between 7-9 years for 40.8 percent of the machines. The frequency of use ranged from 21-30 days per year for 45.24 percent of the foggers. Out of the 41 hand-carried thermal foggers tested before evaluation, all met the standard criteria for chemical flow rate, pipe end temperature, and span value, while the VMD of the chemical droplet met 53.66 percent of the standard. Overall, 53.66 percent of hand-carried thermal foggers passed the standard criteria across all four aspects. However, it is noteworthy that a significant portion (46.34 percent) did not meet the criteria, which could potentially affect the effectiveness of disease control. Therefore, a thorough check and evaluation of standards should be conducted before using hand-carried thermal foggers for disease control purposes including chemical droplet met checkup.