category of biosecurity policies are quarantine measures adopted to counteract the spread of disease and, when applied as a component of border control, focus primarily on mitigating the entry of infected individuals, plants, or animals into a country. Other aspects of biosecurity related to border control include mandatory vaccination policies for inbound travellers and measures to curtail the risk posed by bioterrorism or invasive species. Quarantine measures are frequently implemented with regard to the mobility of animals, including both pets and livestock. Notably, in order to reduce the risk of introducing rabies from continental Europe, the United Kingdom used to require that dogs, and most other animals introduced to the country, spend six months in quarantine at an HM Customs and Excise pound. This policy was abolished in 2000 in favour of a scheme generally known as Pet Passports, where animals can avoid quarantine if they have documentation showing they are up to date on their appropriate vaccinations. In the past, quarantine measures were implemented by European countries in order to curtail the Bubonic Plague and Cholera. In the British Isles, for example, the Quarantine Act 1710 (9 Ann.) established maritime quarantine policies in an era in which strict border control measures as a whole were yet to become mainstream. The first act was called for due to fears that the plague might be imported from Poland and the Baltic states. The second act of 1721 was due to the prevalence of the plague at Marseille and other places in Provence, France. It was renewed in 1733 after a new outbreak in continental Europe, and again in 1743, due to an epidemic in Messina. In 1752 a rigorous quarantine clause was introduced into an act regulating trade with the Levant, and various arbitrary orders were issued during the next twenty years to meet the supposed danger of infection from the Baltic states. Although no plague cases ever came to England during that period, the restrictions on traffic became more stringent, and in 1788 a very strict Quarantine Act was passed, with provisions affecting cargoes in particular. The act was revised in 1801 and 1805, and in 1823–24 an elaborate inquiry was followed by an act making quarantine only at the discretion of the Privy Council, which recognised yellow fever or other highly infectious diseases as calling for quarantine, along with plague. The threat of cholera in 1831 was the last