How bad is Hong Kong’s summer rat problem?
Everything you need to know about the rodent infestation, from the diseases they carry to what to do if there’s a mouse in your house
Hong Kong residents and pest control experts have been reporting a rampant rodent problem since the beginning of the summer, with an exceptionally long hot spell possibly encouraging the vermin to breed and alter their usual behaviour.
1. Is the rodent infestation serious?
The city’s Food and Environmental Hygiene Department has been using the rodent infestation rate (RIR) for areas under its management since 2000 as an index. The RIR for the second half of 2017 for the city as a whole was 3.5 per cent, down from 4 per cent in 2016. The department said rodent infestation in the city was “not extensive” and “generally under control”. But it also said the RIR might not fully reflect the situation in individual districts.
Over the years, there have been occasional media reports about rodent bites. The last case of the plague – a deadly infectious disease linked to rodents and their fleas – reported to the city’s health authorities was in 1929. In 1894, the disease claimed at least 2,500 lives in four months in Hong Kong. Outbreaks of varying seriousness continued to occur up to 1929.
2. What rodents are commonly found in Hong Kong?
Common species in Hong Kong are Rattus norvegicus, also known as the sewer rat, Norway rat or brown rat; Rattus rattus, also called the house rat or roof rat; and Mus musculus, or more commonly, the house mouse. These social and highly adaptable animals are nocturnal and are good climbers and swimmers, especially Rattus rattus. The range of movement is 30 to 50 metres for rats, and five to 10 metres for mice. A rat can consume 15 to 30 grams of food daily. A mouse consumes only three grams of food.
