Super rats

The 1990's has seen the emergence of new "super" strains of disease and infection in developing and developed countries, resistant to existing treatments, and apparently caused by a range of changing environmental factors. The emergence of "super-rats," particularly in the developed world, and particularly in cities and urban areas appears to follow this same trend.

These super-rats, immune to traditional poisons and capable of eating their way through sewer pipes, are less afraid of humans than their predecessors. Their increase in number, to plague proportions in some cities, is believed to be caused by the recent milder winters and the rising number of fast food outlets – generating more food waste in the streets – making it easier for rats to survive. The super-rats are believed to carry more disease than previously thought and pose a serious health risk. Evidence exists that these super-rats are developing degrees of immunity to existing rodenticides while others are developing behaviour patterns, testing small amounts of bait foods before consuming sufficient quantities for poisons to work.

UK Government figures in 1997 report a 40 percent increase in rat population numbers since 1970, amounting to 60 to 70 million in the UK. While the majority of these numbers are not super-rats, concern exists that the change in the population to super-rats in taking place and that eventually super-rats could become the norm. Pest control experts in the UK blame the increase on the failure to develop new poisons and the widespread installation of cheaper, inefficient drainage pipes in sewers which super-rats can chew through. Others blame local authorities and the new private water companies for failing to coordinate strategies against rats.