ABSTRACT
ObjectiveTo analyze the interannual fluctuation， seasonal fluctuation， habitat distribution and the correlation of the 3 monitoring indicators of Aedes albopictus in Yangpu District of Shanghai from 2017 to 2021， and to provide a scientific basis for A. albopictus control and rational use of the indicators. MethodsThe density surveillance data of A. albopictus recorded by Breteau index （BI）， Path index （PI） and the mosquito ovitrap index （MOI） from 2017 to 2021 in Yangpu District， Shanghai were compared. Microsoft Excel 2019 software was used for data summary and SPSS 25.0 software was used for statistical analysis. ResultsFrom 2017 to 2021， there were two months with BI>5， and the PI were all above the density control level of Class C， and there were nine months with MOI≥5. In 2017， BI was higher than in the other four years， with statistically significant differences （all P≤0.001）. MOI in 2017 and 2020 was higher than in 2019 （P=0.029， P=0.004） and 2021 （P=0.005， P=0.001）， with statistical significance. MOI for different types of habitats varied significantly， with a statistically significant difference （P=0.004）. A linear correlation was observed between BI and PI （r=0.462， P=0.010）. ConclusionBI， PI and MOI are used simultaneously to reflect the density of A. albopictus in Yangpu District of Shanghai. However， these three monitoring indicators show poor linear correlation. Comprehensively considering the scientific aspects of monitoring methods and seasonal fluctuations of indicators， it is suggested that MOI should be used as the main index to evaluate the density of A. albopictus. In the MOI， attention should be paid to factors such as the distribution of the habitats， the standardization of operating methods， and quality control， which are essential for enhancing the reliability of the MOI.
ABSTRACT
Objective To investigate the resistance dynamics of Blattella germanica to commonly used insecticides in Yangpu District of Shanghai during 2014‒2020， and to provide the basis for the rational use of insecticides against cockroaches. Methods Blattella germanica was captured in two farmer’s markets in 2014， 2017 and 2020. The residual film method recommended by WHO was used to test resistance of Blattella germanica to the insecticides. Results In 2014， 2017 and 2020， the resistance ratio of Blattella germanica in Yangpu District was 6.96， 4.39， 7.26 to beta-cypermethrin， 10.41， 6.71， 5.24 to permethrin， and 2.28， 3.16， 1.01 to propoxur. Conclusion The resistance of Blattella germanica to permethrin and propoxur decreases， and the resistance to beta-cypermethrin keeps at low level. Comprehensive management and rotation of insecticides should be implemented to delay the increase of resistance.
ABSTRACT
Objective To investigate the resistance development of Aedes albopictus to commonly used insecticides in Yangpu District of Shanghai， China， and to provide scientific bases for the control of A. albopictus and the emergency treatment of dengue fever. Methods The larva immersion method recommended by WHO was used to assay the median lethal concentration （LC50） of A. albopictus larva. SPSS 25.0 was used to calculate the toxicity baselines of insecticides. Results A. albopictus kept a medium resistance to beta-cypermethrin， and the resistance ratios were 14.44， 10.00， 17.78， respectively， in 2015， 2017， 2019. The mosquitos kept a high resistance to permethrin， and the resistance ratios were 54.00， 140.00， 52.00 respectively， in 2015， 2017， 2019. Besides， A. albopictus also kept a medium resistance to propoxur， and the resistance ratios were 15.34， 13.06， 10.83 respectively， in 2015， 2017， 2019. To deltamethrin， A. albopictus showed high resistance in 2015 and medium resistance in 2017， the resistance ratios were 40.00 and 35.00. To temephos， A. albopictus showed low resistance in 2015， with the resistance ratio of 9.38. Conclusion A. albopictus has developed high resistance to permethrin in Yangpu District of Shanghai， and cautious and reduced use of permethrin is suggested. It is necessary to implement and adopt the strategy of comprehensive management， in order to establish the long-term mechanism for mosquito control and prevention.