Objective To investigate the efficacy of three mosquito attractants (Attractant A, B, and C), carbon dioxide (CO ₂) at different flow rates and attractant combined with CO ₂in attracting Aedes albopictus, to screen out the optimal combination, and to provide a scientific basis for the application of chemical pheromone monitor in the field work of Ae. albopictus surveillance. Methods A remote-controlled chemical pheromone mosquito trap monitor was used to perform the trapping test. A total of 200 Ae. albopictus mosquitoes were placed in the simulation room, and the trapping test was conducted for the three mosquito attractants, CO ₂ at different flow rates, and attractant combined with CO ₂, and efficacy was observed after 24 hours. The Chi-square test and the logistic regression analysis were used to compare and analyze the efficacy of different attractants and CO ₂ flow rates in trapping Ae. albopictus. Results CO ₂ at a flow rate of 80, 150, and 200 ml/min had mean trapping rates of 50.42%, 64.67%, and 74.33%, respectively, and attractant A, B, and C had mean trapping rates of 66.40%, 70.30%, and 53.00%, respectively. Attractant A combined with CO ₂ at a flow rate of 80, 150, and 200 ml/min had mean trapping rates of 66.67%, 67.33%, and 79.67%, respectively, and attractant B combined with CO ₂ at a flow rate of 80, 150, and 200 ml/min had mean trapping rates of 70.67%, 78.67%, and 82.33%, respectively. Conclusion In the simulation test, the remote-controlled chemical pheromone mosquito trap monitor with the application of mosquito attractant and CO ₂ has a marked effect in trapping Ae. albopictus, which is better than the use of attractant or CO ₂ alone. The surveillance method can be used for field surveillance and control of vector Aedes mosquitoes.

Objective To investigate the interspecific competition between Aedes aegypti from Wushi town of Leizhou and Ae. albopictus from different places in Guangdong province, China, and to evaluate the dispersal ability of Ae. aegypti. Methods From March to August 2017, 100 second-instar larvae of Ae. aegypti from Wushi town and 100 second-instar larvae of Ae. albopictus from one of selected places in Guangdong province were mixed and raised in a mosquito room. Eighteen days after emergence, all adult mosquitoes were collected with an electric mosquito vacuum for classification and counting, and all mosquito eggs were collected and put in water for next-generation rearing. A total of six generations of mixed rearing were conducted to compare the competitiveness of different species by the number. Results In each generation, Ae. aegypti was the first to emerge, and Ae. albopictus emerged more than three days later. The number of Ae. aegypti from Wushi town of Leizhou was more than the average number of Ae. albopictus in this town and the number of Ae. albopictus from Meizhou in each generation; there were five generations more than that from Maoming, one generation less; there were four generations more than that from Qishui town of Leizhou, Shaoguan and Shenzhen, two generations less; there were two generations more than that from Zhanjiang, four generations less; there was one generation more than that from Guangzhou, five generations less. Conclusion Aedes aegypti from Wushi town of Leizhou has strong competitiveness against Ae. albopictus from Meizhou, Maoming, Shaoguan, and Shenzhen of Guangdong province.

Objective To investigate the mosquito infestation in the mouths of manholes under the municipal administration networks in Shenzhen, Guangdong province, China, and to provide a basis for the prevention and control of mosquito-borne diseases in urban areas. Methods The ponding status, mosquito infestation rate, and mosquito density were investigated in the mouths of manholes under the municipal administration networks of representative subdistricts in the new town areas, old town areas, and urban villages in Shenzhen. The larvae were captured with a 500-ml larva sampling spoon for density (larvae/spoon) calculation. Results A total of 508 mouths of manholes under the municipal administration networks were investigated in November 2017; the mean positive rate of mosquito infestation was 4.7% (including a mean positive rate of Aedes infestation of 3.3%). The mounting rate and maintenance rate of Mosquito Proof Set (the four types of mosquito proof facilities, including mosquito repellent sticks, mosquito proof sluices and nets) were 27.4% and 76.3%, respectively. Of the mouths of positive manholes, 83.3% were not equipped with Mosquito Proof Set. The highest and lowest densities of larvae in the positive manholes were 43 larvae/spoon and 1 larva/spoon, respectively. Relatively high positive rates were observed in water supply manholes (5.9%), sediment manholes (5.7%), and municipal sewage manholes (5.5%). The sediment manholes, municipal sewage manholes, and municipal rainwater manholes had a relatively high constituent ratio both in the overall manholes investigated (84.8%) and in the positive manholes (87.5%). No mosquito infestation was found in the mouths of gas, communication, and power supply manholes. Conclusion The Mosquito Proof Sets are conducive to reducing mosquito infestation in the sewers. Places most seriously infested with mosquitoes are sediment manholes, municipal sewage manholes, and municipal rainwater manholes under the municipal administration networks. The Mosquito Proof Sets can effectively reduce mosquito infestation.

Objective To understand the seasonal variation in the population density of Aedes albopictus in Guangdong province, China, based on a standard surveillance method, and to provide a scientific basis for the early warning and prediction for Aedes-borne diseases. Methods From 2007 to 2017, the population density of Ae. albopictus in Guangdong province was monitored by Breteau index (BI), mosquito ovi trap index (MOI), and the mosquito light trap method. Results The Ae. albopictus larvae density surveillance in 9 506 102 houses resulted in a mean BI value of 2.94. The adult Ae. albopictus density surveillance using 1 428 078 effective mosquito ovitraps resulted in a mean MOI value of 4.98. The adult Ae. albopictus density surveillance using 82 019 effective mosquito light traps resulted in an overall Ae. albopictus density of 0.21 mosquito/lamp·night. Between-group comparison made by analysis of variance and the Bonferroni method showed that there was a significant difference in BI surveillance results between different environments ( F=69.158, P<0.01). However, there were no significant differences in MOI or mosquito light trap surveillance results between different environments ( F=1.642, P=0.174; F=1.973, P=0.081). According to the surveillance results by the three methods, the population density of Ae. albopictus was higher in summer and autumn than in winter and spring. Conclusion Aedes albopictus exists all the time of a year in Guangdong province. The population density of Ae. albopictus varies with year, and season. Therefore, the prevention and control of Ae. albopictus should be performed on a case-by-case basis. The sensitivity of a surveillance method varies with environment, suggesting that the selection of surveillance methods should depend on the surveillance environment.

Objective To understand the distribution status of Aedes aegypti and Ae. albopictus in Leizhou and assess the risk of dengue and Zika virus diseases transmission. Methods From July to August in 2017, using remote sensing technology and geographic information system (GIS), the distributions of Ae. aegypti in Wushi, Qishui and coastal villages of Leizhou, Guangdong province were investigated by larval straw method and mosq-ovitrap method. Results Seventy-nine (79) residential buildings and 23 fishing vessels were investigated in Wushi and 55 residential buildings and 28 fishing vessels in Qishui. There were 34 positive places of Aedes mosquitoes in Wushi, of which 17 were positive for Ae. aegypti, 14 were positive for Ae. albopictus, and 3 were positive for both. There were 17 positive places of Aedes mosquitoes in Qishui, of which 4 were positive for Ae. aegypti and 13 were positive for Ae. albopictus. In total, 308 bodies of water in 15 coastal villages from Liusha to Jijia were investigated and only Ae. albopictus was found without Ae. aegypti. Aedes aegypti mostly breed in water storage containers of residential buildings and fishing vessels, while Ae. albopictus mostly breed in outdoor tires. Conclusion Aedes aegypti was only found in Wushi and Qishui in Leizhou, and its population and distribution range had a decreasing trend. Large-scale wooden fishing vessels in the two towns still had the Ae. aegypti distribution.

Objective To assess the mosquito-killing effect of ultra-low-volume spraying machine during night and day in community and Zhongshan Park at Shaoguan, and provide the scientific basis to choose scientific and effective mosquito-killing technology. Methods Used the large vehicle-mounted ultra-low-volume machine spraying pesticide to kill mosquitoes in Shaoguan communities and park environment, respectively during night and day, then evaluated mosquito-killing effect of applying pesticide spray during night and day by Mosq-ovitrap positive index (MOI) and human-bait of monitoring Aedes density before and after applying pesticide. Results After ultra-low-volume spraying during night and day respectively at villa of Shaoguan Country Garden, human-bait index was reduced by 98.19% and 76.85%, MOI by 81.15% and 43.86%; at park, human-bait fell by 76.47% and 77.78% respectively, and MOI fell by -58.54% and 76.33% respectively. Human-bait relative density index of nighttime, daytime spraying at villa was 3.90 and 14.25 respectively, MOI was 38.48 and 24.47; human-bait relative density index at park was 33.82 and 44.44, MOI was 99.09 and 45.68. Conclusion The ultra-low-volume spraying in Shaoguan community environment at nighttime was significantly better than daytime spraying, but in Zhongshan Park the results were similar. In community environment, nighttime ultra-low-volume spraying, compared with spraying during the day, can effectively kill mosquitoes and keep mosquito-borne diseases at low density level, and has a certain application prospect.

Objective To study the efficacy for mosquito control and residual effect of different pesticides by artificial simulation as barrier spray on vegetation. Methods Using insecticidal barrier spray on vegetation technology, Scheffleraoctophylla were sprayed separately by 2.5% effective chloric fluorine with ester millirod suspending agent (Demand), 10% alpha-cypermethrin (Fendona) and 10.4% chlorine chrysanthemum-allyl chrysanthemum water emulsion (alpha-cypermethrin). Then they were moved to an outdoor tent. A total of 30 female Aedes albopictus were put into every tent weekly. One rat and four mosquito oviposition device were introduced into every tent after 24 h, then collected mosquito eggs after 3 d, and recorded survived mosquitoes. Results 2.5% effective chloric fluorine with ester millirod suspending agent remained effective for more than 21 weeks, 10% alpha-cypermethrin for 9 weeks, and 10.4% chlorine chrysanthemum-allyl chrysanthemum water emulsion had no residual effect. The maximum of weekly counts for survivors was 4, 15 and 21 respectively. The median was 1, 5 and 7. Conclusion Both 2.5% effective chloric fluorine with ester millirod suspending agent and 10% alpha-cypermethrin have good mosquito killing and residual effect by using insecticidal barrier spray on vegetation, 2.5% effective chloric fluorine with ester millirod even better.

Objective Application of insecticidal barrier spray on vegetation for dengue mosquito vector control to explore rapid and long-term effective control means for dengue mosquito vector control in the urban communities. Methods From June to September of 2015, the phoenix garden of Shaoguan city in Guangdong province was selected as the test site, comparing the effectiveness of barrier spray on vegetation technology to kill the dengue vector mosquito with the ultra low volume spraying. Results The insecticidal barrier spray on vegetation showed quick kill effect, and continuous control effect on Aedes albopictus, reducing mosquito lure egg apparatus index (MOI) lure under 5 for 2 to 4 weeks, the duration of the MOI under 10 for 3 to 6 weeks, the duration of the effective control of mosquito density for 6 to 7 weeks. Pesticide resistance was not detected. Conclusion Insecticidal barrier spray on vegetation can effectively control dengue mosquito vector density more than one month. Compared with ultra-low volume spraying, insecticidal barrier spray on vegetation reduced the cost by 37.50%, saved on-site manpower, pesticides and time, had a positive impact on dengue fever outbreak control in urban communities.

Objective To investigate the resistance status of Aedes albopictus to used insecticides in the late stage of dengue fever emergency control of Guangdong province in 2014, and learn how to prevent the development of resistance. Methods From the end of October to the beginning of November 2014, larve of Ae. albopictus were collected in epidemic regions in Haizhu and Baiyun district of Guangzhou city, Chancheng and Nanhai district of Foshan city, Chaoyang district of Shantou city, Chao'an district of Chaozhou and Rongcheng district of Jieyang city, and were reared about 1 to 2 generations in the lab, then were tested along with the susceptible larvae according to the methods of national standard “Test Methods of mosquito resistance to insecticides-bioassay methods”(GB/T 26347-2010) to calculate LC₅₀ and resistance index. Results Aedes albopictus of all tested regions had low resistance to temephos and propoxur, the resistant index was 4.92-8.33 and 2.35-6.23 fold respectively. The resistantce to permethrin, beta cypermethrin, deltamethrin resistance were 3.53-31.29 fold, 8.35-38.69 fold, and 2.63-37.04 fold respectively. Of pyrethroid insecticides, Guangzhou city have reached the high level resistance mostly, Foshan city, Chaozhou city mostly low level of resistance, Jieyang city for low level of resistance, Shantou city mostly above the moderate level of resistance against cypermethrin. Aedes albopictus from some cities also have developed resistance to other insecticides in different levels. Conclusion Resistance of Ae. albopictus in the dengue epidemic cities in Guangdong increased very quick to the used insecticides. The control of Ae. albopictus should adhere to the principle of sustainable and integrated management to prevent or delay the development of resistance.

Objective Investigation of epidemiological characteristics of one dengue outbreak in a construction site in Jieyang city, Guangdong province, and evaluation of response outcome. Methods Investigate all cases in the site by epidemiology survey methods, collect blood samples from the workers for antibody detection and nucleic acid test, and survey the density of mosquito larvae by Breteau index. Results The 22 cases in total happened within 16 d, the first case on 26^th September and the last case on 12^th October with a morbidity of 14.7% (22/150) on this construction site. The mosquito density was decreased after the implement of control measures and the dengue outbreak was effectively contained. The isolates of dengue virus from cases had high similarity with the isolates from Guangzhou cases by Dengue virus phylogenetic analysis. Conclusion The outbreak was caused by dengue virus type 1. The source of infection might have come from Guangzhou. Early cases were not recognized in time due to misdiagnosis which led to the spread of dengue on a construction site. The key point for the successful prevention and control of dengue fever was the timely response of governmental departments and the effective implementation of mosquito control measures.

Objective To study the community structure, dynamic and West Nile virus (WNV) carried of mosquito vectors in Guangdong, and provide scientific evidence for further development of control and prevention strategies. Methods Mosquito density was monitored by Light-trap from May 2013 to April 2014. One-step reverse-transcript PCR was applied. Results The average density of mosquito was 11.80/light. The seasonal peak of density was from May to July. Of all habitats the density in the barn was the highest. Culex pipiens quinquefasciatus accounts for 89.90%, the largest proportion of mosquitoes. No positive was found by RT-PCR. Conclusion Culex pipiens quinquefasciatus was the predominant species, the monitoring data could provide scientific basis for the control strategies and warning and forecasting of WNV, but the vectors species of West Nile fever in Guangdong province and its spread risk needs to be further studied.

Objective To understand Wolbachia distribution and genotype among mosquito populations in Guangdong. Methods PCRs were performed on mosquitoes from Culex, Aedes, Anopheles and Armigeres based on Wolbachia wsp gene, PCR products were sequenced and performed phylogenetic analysis using molecular biology software (Mega 5.2). Results Twelve samples were positive on Cx. pipiens quinquefasciatus, Ar. subalbatus, Ae. albopictus and unidentified Culex, 11 of them were successfully sequenced, phylogenetic analysis revealed they were divided into 5 clades belonged to Wolbachia supergroup A and supergroup B. Conclusion Both supergroup A and supergroup B were detected among Cx. pipiens quinquefasciatus, Ar. subalbatus, Ae. albopictus, but not in Ae. aegypti and Anopheles sinensis samples.

Objective To investigate the resistance levels of Musca domestica to four commonly used insecticides in the special places such as landfill and meat processing plant in Guangdong province, China. Methods M. domestica larvae were collected in the wild breeding habitats, and topical application was used to determine the median lethal doses (LD₅₀) of permethrin, deltamethrin, beta-cypermethrin, and DDVP for M. domestica. The experimental data were statistically analyzed by extremum method. Results The LD50 of permethrin, deltamethrin, beta-cypermethrin, and DDVP were 13.7179, 3.5971, 5.5982, and 0.7704 μg/insect, respectively, for M. domestica in the landfill and were 1.0999, 0.7278, 8.3314, and 0.5322 μg/insect, respectively, for M. domestica in the meat processing plant. The resistance ratios were 58-2525, increased 1-103 times compared with those in 1996 and increased 2-1383 times compared with those in 1991. The resistance of M. domestica to permethrin, deltamethrin, and DDVP was higher in the landfill than in the meat processing plant. Conclusion M. domestica develops high resistance to some insecticides in the special places in Guangdong province, and the resistance to pyrethroid increases rapidly. Comprehensive management strategies and proper insecticide use should be adopted to control M. domestica in the special places such as landfill and meat processing plant.

Objective To analyze the association between prevalence of Chikungunya fever and Mosq-ovitrap index (MOI) and to investigate the infection with Chikungunya virus (CHIKV) in larval and adult Aedes albopictus. Methods Mosquitoes were collected by mosq-ovitrap and the mosquito density was also determined by Breteau index (BI) during Chikungunya fever outbreak. CHIKV was detected in the Ae. albopictus samples collected in the field by real-time fluorescence PCR and cell culture for isolation. Results Comprehensive emergency control measures were taken for anti-mosquito purpose after the confirmation of Chikungunya fever outbreak. After one week of ergency management, the epidemic situation was effectively controlled, as shown by the fact that both MOI and BI were lower than 5. The collected mosquito samples were divided into 27 groups according to collection time and location, and then CHIKV detection was performed. The results showed that all adult mosquito samples were virus negative, and 3 larval mosquito samples soaked in alcohol were questionably positive, counting for 12.5% of all 24 larval mosquito samples. There were only negative results in the virus detection based on cell culture and isolation. A total of 253 cases were reported in the community with Chikungunya fever outbreak, and the emergency control measures lasted for 22 days. Conclusion As for responding to Chikungunya fever outbreak, mosq-ovitrap is safe, effective, and easy-to-operate for indicating emergency mosquito control, especially for evaluating control efficacy and detecting virus in adult mosquitoes. The infection rate and transmission rate of CHIKV in Ae. albopictus during Chikungunya fever outbreak deserve further study in the future.

Objective To determine the characteristics and dynamics of mosquito population during the process of rapid urbanization, and to identify the relationships between the dynamic of main vectors and rapid urbanization. Methods The mosquito density was investigated for the past four years using the human-bait method. Results Five species of mosquito were captured, including Culex tritaeniorhynchus, Culex pipiens quinquefasciatus, Anopheles sinensis, Aedes albopictus, and Armigeres subalbatus. Cx. pipiens quinquefasciatus was predominant (92.27%), followed by Ar. subalbatus (3.98%). The proportions of Ae. albopictus and Cx. tritaeniorhynchus were relatively small, accounting for 1.62% each. The smallest was An. sinensis (0.51%). During a four-year study period, significant changes had taken place in the proportions of mosquito populations by comparison among the data in 2006, 2008 and 2009. The population of Cx. pipiens quinquefasciatus decreased while increased of that of Ae. albopictus. An. sinensis gradually disappeared as the time elapsed. The poplation of Cx. tritaeniorhynchus fluctuated largely in the study periods. In the evening, varieties of mosquito species showed distinct activity patterns. The biting time of Cx. pipiens quinquefasciatus and Cx. tritaeniorhynchus was from 19: 00 to 22: 00 in the evening with a peak after 21: 00. Ae. albopictus could be caught all the night with the main peak before 20: 00. A similar activity pattern was observed from Ar. subalbatus and Ae. albopictus. Conclusion During the process of rapid urbanization, the population of the dengue vector, Ae. albopictus, increased gradually. The population of the Japanese encephalitis vector, Cx. tritaeniorhynchus, fluctuated greatly in different years. However, the malaria vector, An. sinensis, eventually was not found. Thus, we propose that the surveillance and control of Ae. albopictus and Cx. tritaeniorhynchus should be strengthened during the process of urbanization.

【Abstract】 Objective To test the efficacy of four kinds of electric liquid repellents (A 0.12% dimefluthrin, B 0.17% dimefluthrin, C 0.86% transfluthrin, D 0.86% prallethrin) for the Japanese encephalitis(JE) vectors in the field. Methods The landing count method was used to the investigation of mosquito density before and after treatment by electric liquid repellent. Results The main species caught in the field were Culex pipiens quinquefasciatus and Cx. tritaeniorhynchus, which were the JE vector. Only  sample  A  reached ＞80%  population  reduction  of  Cx. tritaeniorhynchus. Both sample B, C and D caused ＜80% population reduction of Cx. tritaeniorhynchus. Both sample A, C and D caused ＞80% population reduction. However, only sample B led to 70%-80% population reduction. Conclusion The tests suggest that four samples have a good repellent effect on mosquito, but the efficacy of sample B is less than that of sample A, C and D. There are different for the control efficacy of different electric liquid repellent in the lab and the field.

【Abstract】 Objective A field study was carried out in a restaurant in the south of China to investigate the blood sources affected Japanese encephalitis （JE） vectors Culex tritaeniorhynchus and Cx.pipiens quinquefasciatus indoor abundance. Methods Vector density was investigated by human?leg capture technique. Results In the dinning room adjacent to deer blood resource, Cx.tritaeniorhynchus was the dominant specie（74.80% of total number） and the minor vector was Cx.pipiens quinquefasciatus （21.14%）. However, in the restroom where the mosquitoes could only access to human blood,  Cx.pipiens quinquefasciatus accounted for 60.28% and that of Cx.tritaeniorhynchus was 36.62%（n＝845）. The density of Cx.tritaeniorhynchus in restroom was higher than that in the dinning room （df＝1, χ2＝5.32，P＜0.05, n＝676）. However, the density of Cx.pipiens quinquefasciatus in the dinning room was higher than that in the restroom（df＝1, χ2＝268.45， P＜0.001, n＝611）. Conclusion The results showed that the blood resources influenced the JE vector spatial abundance. The abundance of Cx.tritaeniorhynchus or Cx.pipiens quinquefasciatus was affected by the animal blood or the human blood.

Objective To study the resistance development of anticoagulant rodenticide in commensal rodents. Methods Tests was carried out without selectivity by rodents based on the method of National Rodenticide Resistance Monitoring Co-worker Group. Results 769 Rattus flavipectus and 303 Rattus norvegicus were caught in five cities of Guangdong were tested. The resistance rate differs from 1.69 to 12.21 the average dosage taken differs from 10.36 mg/kg to 131.96 mg/kg . The result showed that Rattus flavipectus and Rattus norvegicus had become individual resistance to the resistance rodenticide Ⅰ. Conclusion The anticoagulant rodenticide Ⅱ should be used in the areas gathered with Rattus flavipectus. The anticoagulant rodenticide Ⅰ can be still used but should be used scientifically and properly with careful tests of sensitivity.

Objective To evaluate the toxic effects of bednets impregnated with pyrethroid for Anopheles anthropophagus in laboratory.Methods During the tests of mortality the plastic funnels were provided by WHO for bioassay and KT ₅₀,LT ₅₀.Results In laboratory,bednets impregnated with(250 mg a.i/m ² and(500 mg a.i/m ² permethrin caused 73.7% mean mortalities within 10 months and 77.0% within 13 months respectively on laboratory-bred (An.anthropophagus).The KT ₅₀ for An.anthropophagus was 16.2-18.7 min averagely(16.9 min) as determined 180-305 days after the permethrin-impregnated bednets at the dose of 500 mg a.i/m ² while the LT ₅₀ was 18.1-26.7 min averagely 22.1 min.The ratio of KT ₅₀ to LT ₅₀ was(1∶1.3).Bednets impregnated with 20 mg a.i/m ² and 10 mg a.i/m ² cyhalothrin caused average mortalities of 79.80 and 73.5% within one year on An.anthropophagus respectively.And bednets impregnated with 40 mg a.i/m ² and 20 mg a.i/m cyfluthrin caused average mortalities of 78.1% within 8 months and 73.2% within 6 months on An.anthropophagus respectively.Conclusion It showed that bednets impregnated with 500 mg a.i/m ² permethrin,20 mg a.i/m ² cyhalothrin and(40 mg a.i/m ² cyfluthrin have longer residual effect and stronger killing effect.Can effectively control An.sinensisand malaria in China.

Objective To study the resistant development of anticoagulant rodenticide in commensal rodents. Methods Unselective feeding method was used,which was established by "Rodenticideresistance Monitoring Cooperation Group in China" in 1985. Results The rodents (155 Rattus norvegicuus,13 Rattus flavipectus and 28 Mus musculus) caught in Qingyuan and it's three county city zone of Guangzhou province were tested. The resistance rate differs from 0.65%?0 to 50.00% for Rattus norvegicus, Rattus flavipectus and Mus musculus with average taken dosages 9.82,84.92 to 453.70 mg/kg respectively. The result shows that Mus musculus have developed resistance to anticoagulant rodenticide Ⅰ and Rattus norvegicus has individual resistance. Conclusion The resistance rodenticide Ⅱ should be used in the areas Mus musculus more than others. The anticoagulant rodenticide Ⅰ can be still used but should be used scientifically and properly with careful tests of sensitivity.

Objective To investigate SARS coronavirus carried by or reserved in rat and cockroach,and try to provide the evidence for the origin and control of SARS coronavirus.Methods Nested reverse-transcript PCR and fluorescent quantitative reverse-transcript PCR were applied.Results With SARS Cov.-specific primer,a total of 160 rat lung tissues and 15 cockroach surface swabs were tested in nested RT-PCR and fluorescent quantitative RT-PCR.No positive was found by fluorescent quantitative RT-PCR,and only one uncertain positive result of cockroach surface by nested RT-PCR.Conclusion Nested RT-PCR and fluorescent quantitative RT-PCR are available in fast testing positive vector,and there was no evidence to regard the role of rat and cockroach in the origin and transmission of SARS coronavirus,which deserves to be studied further in the future.