Beginning in the early 20th century, a number of states have passed laws mandating medical examinations for one or both parties before marriage. The most common requirement was a blood test for syphilis, though other diseases such as gonorrhea and rubella were sometimes also targeted. If a partner tested positive, they would generally be required to undergo treatment before they could receive a marriage license. Such laws were once widespread in the United States, with all but eight states requiring premarital blood tests by 1954. Mandatory testing was also in effect in parts of Canada, and some European nations such as Sweden. Most of these laws were repealed by the late 20th or early 21st century. Tests Syphilis Syphilis was the disease most commonly targeted by premarital examination laws. Syphilis was relatively widespread in the first half of the twentieth century, estimated to affect more than 10% of Americans during their lifetime, with many of those afflicted unaware that they were carrying the disease. Because syphilis could be transmitted from mother to child, and cause birth defects, detecting the presence of the disease prior to marriage (and the subsequent production of offspring) was seen as a beneficial public health measure. The most common blood test for syphilis was the Wassermann test, developed in 1906 by August von Wassermann, though results of the alternative Kahn test were also usually accepted. If a partner tested positive, they would generally be required to undergo a course of treatment until a doctor was satisfied that the infection was resolved. Before the introduction of penicillin as an effective single-dose treatment in the 1940s, patients were treated with arsenic-based drugs such as Arsphenamine which took a year or more to clear the infection. HIV Beginning in the 1980s, a number of national and subnational governments have implemented or considered implementing mandatory HIV testing prior to marriage. As of 2010, regions with such laws in effect included Bahrain, certain provinces of China, Libya, Saudi Arabia, the United Arab Emirates, and Uzbekistan. In the United States, more than thirty states considered premarital HIV testing laws in the 1980s, with Illinois and Louisiana briefly enacting mandatory testing statutes. Only a small number of statutes under consideration would have barred the issuance of a marriage license in the case of a positive test. In some areas, premarital HIV tests are mandated by local churches, such as the Church of Uganda,