aggressive. Despite their needs, prairie dogs are very social animals and come to seem as though they treat humans as members of their colony. In mid-2003, due to cross-contamination at a Madison, Wisconsin-area pet swap from an unquarantined Gambian pouched rat imported from Ghana, several prairie dogs in captivity acquired monkeypox, and subsequently a few humans were also infected. This led the CDC and FDA to issue a joint order banning the sale, trade, and transport within the United States of prairie dogs (with a few exceptions). The disease was never introduced to any wild populations. The European Union also banned importation of prairie dogs in response. All Cynomys species are classed as a "prohibited new organism" under New Zealand's Hazardous Substances and New Organisms Act 1996, preventing it from being imported into the country. Prairie dogs are also very susceptible to bubonic plague, and many wild colonies have been wiped out by it. Also, in 2002, a large group of prairie dogs in captivity in Texas were found to have contracted tularemia. The prairie dog ban is frequently cited by the CDC as a successful response to the threat of zoonosis. Prairie dogs that were in captivity at the time of the ban in 2003 were allowed to be kept under a grandfather clause, but were not to be bought, traded, or sold, and transport was permitted only to and from a veterinarian under quarantine procedures. On 8 September 2008, the FDA and CDC rescinded the ban, making it once again legal to capture, sell, and transport prairie dogs. Although the federal ban has been lifted, several states still have in place their own ban on prairie dogs. The European Union has not lifted its ban on imports from the U.S. of animals captured in the wild. Major European Prairie Dog Associations, such as the Italian Associazione Italiana Cani della Prateria (AICDP), remain against import from the United States, due to the high death rate of wild captures. Several zoos in Europe have stable prairie dog colonies that generate enough surplus pups to saturate the EU internal demand, and several associations help owners to give adoption to captive-born animals. Prairie dogs in captivity may live up to ten years. Literary descriptions From George Wilkins Kendall's account of the Texan Santa Fe Expedition: "In their habits, they are clannish, social, and extremely convivial, never living alone like other animals, but,