the commission had evolved into the uk's medical research council. in 1902, the international conference on tuberculosis convened in berlin. among various other acts, the conference proposed the cross of lorraine be the international symbol of the fight against tuberculosis. national campaigns spread across europe and the united states to tamp down on the continued prevalence of tuberculosis. after the establishment in the 1880s that the disease was contagious, tb was made a notifiable disease in britain; there were campaigns to stop spitting in public places, and the infected poor were pressured to enter sanatoria that resembled prisons; the sanatoria for the middle and upper classes offered excellent care and constant medical attention. whatever the purported benefits of the fresh air and labor in the sanatoria, even under the best conditions, 50% of those who entered were dead within five years (1916). the promotion of christmas seals began in denmark during 1904 as a way to raise money for tuberculosis programs. it expanded to the united states and canada in 1907–1908 to help the national tuberculosis association (later called the american lung association). a chart showing the rate of tuberculosis in inspected livestock in a 1938 publication of the united states department of agriculture. in the united states, concern about the spread of tuberculosis played a role in the movement to prohibit public spitting except into spittoons. public health measures were inaugurated to track and control the prevalence of tuberculosis in livestock that could be transmitted to humans. vaccines the first genuine success in immunizing against tuberculosis was developed from attenuated bovine-strain tuberculosis by albert calmette and camille guérin in 1906. it was called "bcg" (bacille calmette-guérin). the bcg vaccine was first used on humans in 1921 in france, but it was not until after world war ii that bcg received widespread acceptance in great britain, and germany. in the early days of the british national health service x-ray examination for tb increased dramatically but rates of vaccination were initially very low. in 1953 it was agreed that secondary school pupils should be vaccinated, but by the end of 1954 only 250,000 people had been vaccinated. by 1956 this had risen to 600,000, about half being school children. in italy, salvioli's diffusing vaccine (vaccino diffondente salvioli; vds) was used from 1948 until 1976. it was developed by professor gaetano salvioli (1894–1982) of the university of bologna. treatments tuberculosis mortality in the usa from 1861 to 2014. specialist nurse at 18-bed 'fresh air school' for children with tb. royal victoria hospital, montreal. 1939. as the century progressed, some surgical interventions, including the pneumothorax or plombage technique—collapsing an infected lung to "rest" it and allow the lesions to heal—were used to treat tuberculosis. pneumothorax was not a new technique by any means. in 1696, giorgio baglivi reported a general improvement in tuberculosis patients after they received sword wounds to the chest. f.h. ramadge induced the first successful therapeutic pneumothorax in 1834, and reported subsequently the patient was cured. it was in the 20th century, however, that scientists sought to rigorously investigate the effectiveness of such procedures. carlo forlanini experimented with his artificial pneumothorax technique from 1882 to 1888 and this started to be followed only years later. in 1939, the british journal of tuberculosis published a study by oli hjaltested and kjeld törning on 191 patients undergoing the procedure between 1925 and 1931; in 1951, roger mitchell published several articles on the therapeutic outcomes of 557 patients treated between 1930 and 1939 at trudeau sanatorium in saranac lake. the search for a medicinal cure, however, continued in earnest. during the nazi occupation of poland, ss-obergruppenführer wilhelm koppe organized the execution of more than 30,000 polish patients with tuberculosis – little knowing or caring that a cure was nearly at hand. in canada, doctors continued to surgically remove tb in the indigenous patients during the 1950s and 60s, even though the procedure was no longer performed on non-indigenous patients. in 1944 albert schatz, elizabeth bugie, and selman waksman isolated streptomycin produced by a bacterial strain streptomyces griseus. streptomycin was the first effective antibiotic against m. tuberculosis. this discovery is generally considered the beginning of the modern era of tuberculosis. para-aminosalicylic acid, discovered in 1946, was used in combination with streptomycin to reduce the emergence of drug resistant variants, which greatly improved patient outcomes. the true revolution began some years later, in 1952, with the development of isoniazid, the first oral mycobactericidal drug. the advent of rifampin in the 1970s hastened recovery times, and significantly reduced the number of tuberculosis cases until the 1980s. the british epidemiologist thomas mckeown had shown that "treatment by streptomycin reduced the number of deaths since it was introduced (1948–71) by 51 per cent...". however, he also showed that the mortality from tb in england and wales had already declined by 90 to 95% before streptomycin and bcg-vaccination were widely available, and that the contribution of antibiotics to the decline of mortality from tb was actually very small: '...for the total period since cause of death was first recorded (1848–71) the reduction was 3.2 per cent'.: 82 these figures have since been confirmed for all western countries (see for example the decline in tb mortality in the usa) and for all then known infectious diseases. mckeown explained the decline in mortality from infectious diseases by an improved standard of living, particularly by better nutrition, and by better hygiene, and less by medical intervention. mckeown, who is considered as the father of social medicine, has advocated for many years, that with drugs and vaccines we may win the battle but will lose the war against diseases of poverty. thereto, efforts and resources should be primarily directed toward improving the standard of living of people in low resource countries, and toward improving their environment by providing clean water, sanitation, better housing, education, safety and justice, and access to medical care. particularly the work of nobel laureates robert w. fogel (1993) and angus deaton (2015) have greatly contributed to the recent reappreciation of the mckeown thesis. a negative confirmation of the mckeown thesis was that increased pressure on wages by imf loans to post-communist eastern europe were strongly associated with a rise in tb incidence, prevalence and mortality. in the united states there was dramatic reduction in tuberculosis cases by the 1970s. as early as the 1900s, public health campaigns were launched to educate people about the contagion. in later decades, posters, pamphlets and newspapers continued to inform people about the risk of contagion and methods to avoid it, including increasing public awareness about the importance of good hygiene. though improved awareness of good hygiene practices reduced the number of cases, the situation was worse in the poor neighborhoods. public clinics were set up to improve awareness and provide screenings. in scotland, dr nora wattie led the public health innovations both at local and national level. this resulted in sharp declines through the 1920s and 1930s. tuberculosis resurgence hopes that the disease could be completely eliminated were dashed in the 1980s with the rise of drug-resistant strains. tuberculosis cases in britain, numbering around 117,000 in 1913, had fallen to around 5,000 in 1987, but cases rose again, reaching 6,300 in 2000 and 7,600 cases in 2005. due to the elimination of public health facilities in new york and the emergence of hiv, there was a resurgence of tb in the late 1980s. the number of patients failing to complete their course of drugs was high. new york had to cope with more than 20,000 tb patients with multidrug-resistant strains (resistant to, at least, both rifampin and isoniazid). in response to the resurgence of tuberculosis, the world health organization issued a declaration of a global health emergency in 1993. every year, nearly half a million new cases of multidrug-resistant tuberculosis (mdr-tb) are estimated to occur worldwide.