Leptospirosis Cases Surge Due to Floods, Dengue Declines in Philippines

MANILA, Philippines — Floods spawned by typhoons and the southwest monsoon have driven up the number of leptospirosis cases, with over 10,000 infections recorded this year, while dengue infections have declined, according to the Department of Health (DOH). DOH data as of Sept. 16 showed 10,936 suspected cases of leptospirosis this year, which is 38 percent higher than the 7,931 infections reported during the same period in 2025. The number of leptospirosis cases in the past three to four weeks was 116 percent higher than the five to six weeks before that period, the DOH said. The National Capital Region, Cagayan Valley and Calabarzon recorded the highest number of infections. The case fatality rate for leptospirosis is currently 5.1 percent, down from 10.55 percent last year. Meanwhile, the DOH said dengue cases have dropped by 33 percent this year. Data showed that from Jan. 4 to Sept. 16, there were 155,918 dengue cases reported, which is lower by 75,932 than the 231,850 infections recorded during the same period in 2025. However, health officials noted an increasing trend in dengue cases in the recent three to four weeks with 19,792 infections reported, which is 14 percent higher than the 17,342 recorded during the previous five to six weeks. Central Luzon, Calabarzon, and the National Capital Region recorded the highest number of dengue cases. To prevent contracting leptospirosis, the DOH said people must immediately seek medical advice following exposure to floods even if they are not manifesting symptoms of the disease. Some 1.68 million capsules of doxycycline have been sent to health centers in flood-stricken areas nationwide to prevent the spread of leptospirosis, with another 3.73 million capsules available at DOH national and regional warehouses. People have been urged to help prevent the spread of dengue by searching and destroying potential breeding sites of mosquitoes. Those showing symptoms of dengue, which include high fever, headache, body pains nausea or vomiting and rashes, must immediately seek medical attention to prevent complications or death.