Seroprevalence of Leptospira and Description of Work-related Practices and Characteristics among Sewer Workers Servicing Selected Cities in the West Zone of Metro Manila, Philippines

Leptospirosis is a major public health problem in many countries, especially in southeast Asia, including the Philippines. It is considered an occupational risk both in rural and urban settings, notably among sewer workers. Rodents, especially rats, are the most important reservoirs of the disease and can continuously shed Leptospira through their urine – contaminating their surroundings, including the work environment of sewer workers. Despite the apparent occupational risk, there are limited seroprevalence studies conducted among sewer workers in the country. This study reports the current seroprevalence among sewer workers, as well as the Leptospira serovars they are exposed to. Serum samples obtained from 105 sewer workers in the West Zone of Metro Manila were subjected to microscopic agglutination test (MAT). A cut-off titer of 1:100 was used to detect exposure of sewer workers to Leptospira. Results showed that five out of 105 sewer workers were seropositive for Leptospira-agglutinating antibodies, particularly against serovar Mini. The seropositive sewer workers also reported work-related practices and characteristics that might have consistently exposed them to Leptospira-contaminated sewer environments. These practices include wading in combined sewer overflow (CSO), maintenance holes, and septic tanks as a part of their jobs; getting sewer water splashes in their eyes, nose, or mouth while cleaning at least once or twice a week; and going to work despite having cuts or bruises.