Objective To investigate vector density changes in the flood-stricken areas of Hebei Province, China, so as to provide a basis for vector control and the prevention and control of vector-borne diseases in a scientific and orderly manner. Methods The daily monitoring data on the density of mosquitoes, flies, and rodents were collected at 192 resettlement sites in 21 counties/cities/districts of 7 flood-stricken prefecture-level cities in Hebei Province from August to October 2023. The density of mosquitoes and flies was monitored through visual inspection, and the density of rodents was measured using the footprint tracking method. R 4.2.2 software was used to perform the Wilcoxon signed-rank test, Friedman test, and Pearson correlation analysis. Results The average densities of mosquitoes, flies, and rodents of all the resettlement sites were 1.05 inds/labor hour, 0.45 inds/m2, and 0.037 tracks/2 000 m, respectively. The average mosquito density of the resettlement sites showed a slowly fluctuating downward trend, with the highest level on the 1st day of surveillance, reaching 1.97 inds/labor hour, which was lower than the reference level for mosquito control (10 inds/labor hour). The density of flies showed a slowly fluctuating downward trend, with the higher levels on the 1st day (0.71 inds/m2) and the 25th day (1.00 inds/m2) of surveillance, approximating or reaching the reference level for fly control (1 ind/m2). The average rodent density showed a rapidly downward trend, with the peak on the 1 st day at 0.181 tracks/2 000 m, far lower than the rodent control reference level (5 tracks/2 000 m). Pest and rodent control work was completed for a total of 12 586 points covering 1 353 104 m2 of three types of habitats, including resettlement sites and their surroundings, toilets, and garbage points. In August 2023, there were 729 cases of vector-borne diseases in the flood-stricken areas, which were more than the cases in the same period of 2022 (t=-1.429, P=0.002) and 2021 (t=-0.929, P=0.119), similar to the number in the same period of 2020 (t=-0.024, P=1.000), and more than the number in September 2023, the late stage of the flood disaster (W=44.500, P=0.013). From August to September 2023, the local reported no case of mosquito-borne infectious diseases, 1 case of rodent-borne typhus, and 1 215 cases of fly-related diseases (can be mechanically carried and transmitted by flies) diseases such as the other infectious diarrhea and bacillary dysentery; and the number of daily cases was not correlated with the density of flies (r=-0.195, P=0.146). Conclusions The density of mosquitoes, flies, and rodents was low at the resettlement sites of flood-stricken areas in Hebei Province in 2023. When the density exceeded the vector and rodent control reference levels, the implementation of emergency vector and rodent control effectively limited the density of vectors and rodents in the flood-stricken areas and prevented the outbreak of the related diseases.
[1] Liu QY. Epidemic profile of vector-borne diseases and vector control strategies in the new era[J]. Chin J Vector Biol Control,2019,30（1）：1-6,11. DOI：10.11853/j.issn.1003.8280.2019.01.001.（in Chinese） 刘起勇. 新时代媒介生物传染病形势及防控对策[J]. 中国媒介生物学及控制杂志,2019,30（1）：1-6,11. DOI：10.11853/j.issn.1003.8280.2019.01.001.
[2] Ministry of Health of the People's Republic of China,Standardization Administration of the People's Republic of China. GB/T 27774-2011Vector surveillance and control in emergencies—General rules[S]. Beijing：Standards Press of China,2012. （in Chinese） 中华人民共和国卫生部,中国国家标准化管理委员会. GB/T 27774—2011病媒生物应急监测与控制通则[S]. 北京：中国标准出版社,2012.
[3] Ministry of Health of the People's Republic of China,Standardization Administration of the People's Republic of China. GB/T 28944-2012Vector surveillance and control in emergencies—Flood disaster[S]. Beijing：Standards Press of China,2013. （in Chinese） 中华人民共和国卫生部,中国国家标准化管理委员会. GB/T 28944—2012病媒生物应急监测与控制水灾[S]. 北京：中国标准出版社,2013.
[4] Liu QY. Vector surveillance program in Wenchuan earthquake-stricken area （Trial）[Z]. Beijing：Chinese Center for Disease Control and Prevention,2008. （in Chinese） 刘起勇. 汶川地震灾区病媒生物监测方案（试行）[Z]. 北京：中国疾病预防控制中心,2008.
[5] Ye Z,Xia SC. Technical guidelines for integrated vector management[M]. Hangzhou：Zhejiang University Press,2012：267-280. （in Chinese） 叶真,夏时畅. 病媒生物综合防制技术指南[M]. 杭州：浙江大学出版社,2012：267-280.
[6] Shortus M,Musto J,Bugoro H,et al. Vector-control response in a post-flood disaster setting,Honiara,Solomon Islands,2014[J]. Western Pac Surveill Response J,2016,7（1）：38-43. DOI：10.5365/wpsar.2015.6.3.004.
[7] Guo YH,Wu HX,Liu XB,et al. National vectors surveillance report on mosquitoes in China,2018[J]. Chin J Vector Biol Control,2019,30（2）：128-133. DOI：10.11853/j.issn.1003.8280.2019.02.003.（in Chinese） 郭玉红,吴海霞,刘小波,等. 2018年全国媒介蚊虫监测报告[J]. 中国媒介生物学及控制杂志,2019,30（2）：128-133. DOI：10.11853/j.issn.1003.8280.2019.02.003.
[8] Ma LH,Han XL,Gao W,et al. An analysis of adult mosquito ecological surveillance results in Hebei Province,China,2011-2022[J]. Chin J Vector Biol Control,2023,34（4）：508-512,547. DOI：10.11853/j.issn.1003.8280.2023.04.012.（in Chinese） 马丽华,韩晓莉,高文,等. 河北省2011—2022年成蚊生态学监测结果分析[J]. 中国媒介生物学及控制杂志,2023,34（4）：508-512,547. DOI：10.11853/j.issn.1003.8280.2023.04.012.
[9] Qin SC,Zhang X. Surveillance of disease vectors after May 12 earthquake in Aba Prefecture,Sichuan Province[J]. J Prev Med Inf,2009,25（12）：1040-1042. （in Chinese） 秦胜超,张霞. 阿坝州“5.12”地震后病媒生物监测结果分析[J]. 预防医学情报杂志,2009,25（12）：1040-1042.
[10] Hu YJ,Liu QY,Qian WP,et al. Surveillance and analysis of vectors in Wenchuan earthquake-stricken area[J]. Chin J Vector Biol Control,2010,21（1）：9-11. （in Chinese） 胡雅劼,刘起勇,钱薇萍,等. 汶川地震灾区病媒生物监测分析[J]. 中国媒介生物学及控制杂志,2010,21（1）：9-11.
[11] Lalthazuali,Bhan S,Thomas TG,et al. Post flood vector borne disease surveillance：An experience from Malappuram District of Kerala,India in 2018[J]. Int J Mosq Res,2020,7（5）：1-6.
[12] Wu HX,Lu L,Meng FX,et al. Reports on national surveillance of flies in China,2006-2015[J]. Chin J Vector Biol Control,2018,29（1）：5-10. DOI：10.11853/j.issn.1003.8280.2018.01.002.（in Chinese） 吴海霞,鲁亮,孟凤霞,等. 2006—2015年我国蝇类监测报告[J]. 中国媒介生物学及控制杂志,2018,29（1）：5-10. DOI：10.11853/j.issn.1003.8280.2018.01.002.
[13] Ma LH,Gao W,Han XL,et al. Surveillance and specimen reexamination of flies in residential areas of Hebei Province[J]. Chin J Hyg Insect Equip,2022,28（5）：419-425. DOI：10.19821/j.1671-2781.2022.05.009.（in Chinese） 马丽华,高文,韩晓莉,等. 河北省住区蝇类监测及标本复核分析[J]. 中华卫生杀虫药械,2022,28（5）：419-425. DOI：10.19821/j.1671-2781.2022.05.009.
[14] Li CP. Medical entomology[M]. Beijing：People's Military Medical Press,2007：199-237. （in Chinese） 李朝品. 医学昆虫学[M]. 北京：人民军医出版社,2007：199-237.
[15] Wang GW,Liu ZH,Xu CM. Surveillance on vectors in Fangshan District of Beijing after the "7.21" flood[J]. Capital J Public Health,2014,8（6）：279-281. DOI：10.16760/j.cnki.sdggws.2014.06.007.（in Chinese） 王广文,刘朝辉,许春明. 北京市房山区“7.21”水灾后病媒生物监测[J]. 首都公共卫生,2014,8（6）：279-281. DOI：10.16760/j.cnki.sdggws.2014.06.007.
[16] Du JL,Guo QQ,Zhao C,et al. Emergency monitoring and control of vectors after flood in Jintang County of Sichuan Province,China[J]. Chin J Vector Biol Control,2019,30（3）：345-347. DOI：10.11853/j.issn.1003.8280.2019.03.028.（in Chinese） 杜俊龙,郭千秋,赵畅,等. 四川省金堂县洪灾后病媒生物危害应急监测与控制[J]. 中国媒介生物学及控制杂志,2019,30（3）：345-347. DOI：10.11853/j.issn.1003.8280.2019.03.028.
[17] Hou YX,Liu YX,Zhang JL,et al. Emergency surveillance of important vectors after floods in southern Anhui Province in 2016[J]. Chin J Hyg Insect Equip,2021,27（5）：420-424. DOI：10.19821/j.1671-2781.2021.05.009.（in Chinese） 侯银续,刘永孝,张家林,等. 2016年安徽南部洪灾后重要病媒生物应急监测[J]. 中华卫生杀虫药械,2021,27（5）：420-424. DOI：10.19821/j.1671-2781.2021.05.009.
[18] Ma L,Hou YX,Hou S,et al. Results of the vectors surveyed during the flood disaster in Ma'anshan City in 2020[J]. J Trop Dis Parasitol,2022,20（6）：333-335,341. DOI：10.3969/j.issn.1672-2302.2022.06.009.（in Chinese） 马李,侯银续,侯赛,等. 2020年马鞍山市洪涝灾害期间病媒生物调查结果分析[J]. 热带病与寄生虫学,2022,20（6）：333-335,341. DOI：10.3969/j.issn.1672-2302.2022.06.009.
[19] Yang ZZ,Song HB,Sun YS,et al. Strategies for disease management employed Chinese medical troops during a post-earthquake international humanitarian relief mission to Haiti[J]. Chin J Vector Biol Control,2011,22（4）：411-413. （in Chinese） 杨振洲,宋宏斌,孙岩松,等. 海地地震国际人道主义医疗防疫救援中有害生物控制策略的探讨[J]. 中国媒介生物学及控制杂志,2011,22（4）：411-413.
[20] Sun YX. The positive role of pest control operations in post-disaster epidemic management[J]. Chin J Vector Biol Control,2018,29（1）：78-79. DOI：10.11853/j.issn.1003.8280.2018.01.020.（in Chinese） 孙养信. 有害生物防治业在灾后防疫中的积极作用[J]. 中国媒介生物学及控制杂志,2018,29（1）：78-79. DOI：10.11853/j.issn.1003.8280.2018.01.020.
[21] Vigilant M,Battle-Freeman C,Braumuller KC,et al. Harris county public health mosquito and vector control division emergency response to hurricane harvey：Vector-borne disease surveillance and control[J]. J Am Mosq Control Assoc,2020,36（2S）：15-27. DOI：10.2987/19-6890.1.
[22] Liu QY,Meng FX,Fan JC. Vector surveillance and control in emergencies in China：Proceedings and perspectives[J]. Chin J Vector Biol Control,2011,22（1）：1-4. （in Chinese） 刘起勇,孟凤霞,樊景春. 中国重要病媒生物应急监测与控制[J]. 中国媒介生物学及控制杂志,2011,22（1）：1-4.
[23] Wang GW,Liu ZH,Zhang JL,et al. Spatial error statistical analysis on the fly density at the scale of village and town after flooding in Fangshan District,Beijing[J]. Chin J Vector Biol Control,2017,28（5）：433-436. DOI：10.11853/j.issn.1003.8280.2017.05.005.（in Chinese） 王广文,刘朝辉,张进磊,等. 北京市房山区水灾后村庄与乡镇两级水平上蝇密度的空间误差统计分析[J]. 中国媒介生物学及控制杂志,2017,28（5）：433-436. DOI：10.11853/j.issn.1003.8280.2017.05.005.
[24] Liu YX,Zhao YQ,Deng S,et al. Effect of flood disaster on the incidence of correlated communicable disease in Anhui Province,2016[J]. Anhui J Prev Med,2018,24（2）：77-81. （in Chinese） 刘永孝,赵玉秋,邓舒,等. 2016年安徽省洪涝灾害对相关传染病发病的影响[J]. 安徽预防医学杂志,2018,24（2）：77-81.
[25] Zhang BG,Li C,Liu ZX,et al. Discussion on the vector emergency prevention and control measures of the 7.19 flood disaster in Xingtai City,Hebei Province[J]. J Med Pest Control,2018,34（7）：668-670. DOI：10.7629/yxdwfz201807015.（in Chinese） 张保国,李成,刘中霞,等. 河北省邢台市7.19洪灾病媒生物应急防控措施探讨[J]. 医学动物防制,2018,34（7）：668-670. DOI：10.7629/yxdwfz201807015.
[26] Coalson JE,Anderson EJ,Santos EM,et al. The complex epidemiological relationship between flooding events and human outbreaks of mosquito-borne diseases：A scoping review[J]. Environ Health Perspect,2021,129（9）：96002. DOI：10.1289/EHP8887.
[27] Chi D,Zhang GP,Liang XD. Effect of flies and mosquitoes control at railway repair scene after flood disaster[J]. Chin J Hyg Insect Equip,2011,17（5）：362-363,365. DOI：10.19821/j.1671-2781.2011.05.013.（in Chinese） 迟丹,张国平,梁晓东. 洪涝灾后铁路抢修现场蚊蝇防治效果研究[J]. 中华卫生杀虫药械,2011,17（5）：362-363,365. DOI：10.19821/j.1671-2781.2011.05.013.
