Leptospirosis is an infection caused by pathogenic bacteria called Leptospires. It is a zoonosis that is transmitted directly or indirectly from animals to humans. The transmission between humans is very rarely. The number of human cases in Taiwan is 27 to 203 a year and it often peaks seasonally, especially in summer.
Leptospira is long corkscrew-shaped bacteria, and may cause disease in humans by 277 serotypes divided into 25 serogroups. The most common serotype is L. shermani (Leptospira santarosai serovar Shermani) in Taiwan. It could infect both the wild and domestic animals, primarily rodents, and transmitted to human through contact of mucous membranes or (broken) skin with water (swimming or immersion), moist soil or vegetation contaminated with the urine of infected animals. Therefore, the risk factor is high chance to contact contaminated environment or between humans and infected animals. The workers such as farmer, Miners, Veterinarians, fishermen and solders are the risk group.
The most effective protective measures are to prevent contact with the urine of infected animals, the tissue of infected animals or a contaminated environment, and to control animal carrier, e.g. rodents.
Leptospirosis occurs worldwide but is most common in tropical and subtropical areas, and the incidence correlates directly with high rainfall. In Taiwan, epidemics can occur mainly in the plum rain season and typhoon from May to October. In 2009, the typhoon Morakot caused severe flooding in southern Taiwan, there are 203 cases.
Leptospirosis Surveillance in Taiwan
Prevention and Control
To prevent leptospirosis, avoid contact with infected animals and control the reservoir animals.