Laboratory diagnosis of leptospirosis during the acute febrile phase is essential for ensuring patients receive precise and specific treatment to prevent complications and the progression to severe forms of the disease, which can be fatal. Therefore, researchers have developed a highly accurate diagnostic kit for detecting leptospirosis, specifically tailored for use in Thailand. This kit is designed for disease screening and clinical confirmation during unexplained acute febrile episodes, ensuring effective treatment for patients. By utilizing this diagnostic tool, medical practitioners can provide optimal care for severe cases, enhance patient quality of life, prevent complications, and reduce mortality rates.