Density of rodents and its seasonal growth and decline in Ningbo, Zhejiang, 2006–2016

Objective To understand the density of rodents and its seasonal growth and decline in Ningbo, Zhejiang province, and provide evidence for the prevention and control of rodent borne diseases.

Methods The surveillance data of rodent density in Ningbo from 2006 to 2016 were analyzed with software SPSS 16.0 and Excel 2013.

Results Rattus norvegicus and Mus musculus were predominant species in rodents captured in Ningbo, accounting for 86.28% of the total. Two peaks of annual rodent density were observed, but the second one usually lasted from June to October. The growth and decline of rodent density varied with season. The rodent density was higher in natural villages in rural area (was 0.93 per 100 rat traps) than in urban residential areas (0.40 per 100 rat traps) and special sector areas (0.47 per 100 rat traps).

Conclusion The density of rodents showed a decline trend in Ningbo, but it is still important to conduct rodent density surveillance in residential areas and food service sector areas. At the same time it is necessary to establish an early warning system of rodent density based on its growth and decline trend and take comprehensive measures to reduce the rodent density for the purpose of reducing rodent borne diseases.