Data source: Food and Environmental Hygiene Department, HKSAR
Map created by CUHK SpatioEpi Group
Rodent infestation rate
Rodent infestation rate (RIR) = (No. of bait consumed by rodent/ total no. of bait collected from the specific area)*100%
The map shows the RIR for the first half of 2008 in Hong Kong. Yau Tsim Mong has the highest RIR of 16.9% (coloured in red) and Eastern district has the lowest, 2.7%.
When the RIR of a district exceeds the 10 per cent, the Food and Environmental Hygiene Department (FEHD) would step up the rodent disinfestations operations. When an RIR reaches 20 per cent or higher, the relevant Government departments will form a joint task force and launch a special rodent control operation to strengthen rodent disinfestations and cleansing services comprehensively, and to promote rodent control in the community.
In addition, the figure of Yau Tsim Mong is different from the data retrieved from FEHD, it is because FEHD uses 19 districts with Mong Kok as one independent district. Whereas Spatioepi uses the 18 administrative districts to display the data, where Mong Kok is part of Yau Tsim Mong.
鼠患參考指數是鼠餌被老鼠咬囓的比率= (被老鼠咬囓的鼠餌數目 ÷ 仍存的鼠餌總數 × 100%)
Plague is caused by the bacteria Yersinia petis, which is transmitted from rodent to rodent by infected fleas. If bitten by an infected flea, a person usually develops a bubonic form of plague, which is characterised by a swelling of the draining lymph node. While bubonic plague is the commonest, there are also the septicaemic form and pneumonic form. Septicaemic plague occurs when infection spreads directly through the bloodstream, while the pneumonic form is the most virulent but least common. Plague also spreads from human to human by inhalation of aerosolised infective droplets, in the absence of flea or animal.
A Hong Kong outbreak of plague occurred in Tai Ping Shan of Sheung Wan District in 1894. In fact, the bubonic plague bacillus was isolated in Hong Kong at that time by Alexandre Yersin from France.
Further information 詳細資料