When German biologist Robert Koch discovered that the tuberculosis bacillus causes TB - on this day in 1882 - the contagious respiratory disease was killing one out of seven people in Europe.
Today TB, a disease many people think an epidemic of the past, is killing more people than it did back then.
According to the World Health Organization, about 2 million people die from the curable disease every year. Overall, one-third of the world's population is currently infected with the TB bacterium.
In 2004, the Centers for Disease Control and Prevention reported 14,511 cases in the United States. About 54 percent of the people infected with TB were foreign-born.
Alaska had 43 cases in 2004. Four of those occurred in Southeast Alaska.
Although state health officials say the number of cases in Alaska in 2004 was the lowest in state history, the annual number of cases per capita has always been higher than the national average.
Native Alaskans and Asians have a high rate of both latent infection and active transmission of TB.
"Alaska has relatively higher TB rates than the nation due to the legacy of Russia," said Joanne Carter, advocacy chairwoman of the Global STOP TB Initiative of the WHO. "It is a growing epidemic, particularly in Africa, the former Soviet Union and Central Asia. It is the No. 1 killer of people with AIDS."
In some Alaska communities, TB is part of people's daily life. In some other communities, TB is lower than the national average, said Beth Funk, Alaska state TB controller and acting chief of the section of epidemiology.
"In rural Alaska, where we have the highest TB rate, we test schoolchildren annually," Funk said. "We also have targeted skin tests on people who have higher risk."
Like a cold, TB spreads through the air. Only people who are sick with TB are infectious. When infectious people cough, sneeze, talk or spit, they propel TB germs, known as bacilli, into the air. A person needs only to inhale a small number of these to be infected.
If untreated, each person with active TB will infect on average between 10 and 15 people every year, according to WHO.
People infected with TB bacilli will not necessarily become sick with the disease. The immune system blocks the TB bacilli, which can lie dormant for years. But they can become sick with TB when their immune system is weakened.
TB is treatable.
In Alaska, infected people can receive free medicine through local public health centers. The disease is usually treated for six months, but may take longer if doses are missed or certain drugs cannot be used. Treatment of latent TB infection may take up to nine months.
Patients need to check with the center every month to receive new medicine.
"TB is the greatest curable infection on the planet," Funk said. "We need to support our public health system and expand funding to fight the disease globally so it won't come back."