JOHANNESBURG (AP) - A plague outbreak has killed 40 people on the island nation of Madagascar, with 119 people diagnosed with the bacterial disease since August. Two people have been diagnosed and one has died in the capital, Antananarivo. The World Health Organization fears the plague outbreak may spread rapidly through Madagascar's largest and densely populated city, worsened by the country's poor health care system. WHO said a national task force has been set up to manage the outbreak, with the cost of the project reaching $200,000. The international health organization said it is working with the Red Cross and Madagascan health authorities to control the disease. The plague is a disease carried by rodents and spread by fleas. Humans are most often infected when they are bitten by fleas, causing swelling of the lymph nodes and sometimes pneumonia. Combatting the disease in Madagascar has been made more difficult by a high level of resistance to an insecticide used to control fleas, according to WHO. Early treatment and antibiotics have been effective in curing the disease, according to WHO. The bubonic form of the disease, which causes swollen lymph nodes, can be treated with antibiotics. The deadlier pneumonic form, which attacks the lungs, may kill patients within 24 hours, warn health officials. Pneumonic plague is easily spread through coughing but WHO says only two percent of cases reported in Madagascar have been from this highly infectious form of the disease. The first case of the outbreak was found in a village in a district two hours away from Antananarivo. The man was positively diagnosed on Aug. 31 and died days later, according to WHO. Since then 16 other districts have reported cases of plague. The plague is most famous for killing millions of people in Europe during the Middle Ages, according to the Centers for Disease Control and Prevention. Plague infections still occur throughout the world, mainly in parts of Africa and Asia.