Diversity ofLeptospiraspp. in Rats and Environment from Urban Areas of Sarawak, Malaysia

Abstract

Various prevalence studies on Leptospira in animals and humans, as well as environmental samples, had been conducted worldwide, including Malaysia. However, limited studies have been documented on the presence of pathogenic, intermediate, and saprophytic Leptospira in selected animals and environments. This study was therefore conducted to detect Leptospira spp. in rats, soil, and water from urban areas of Sarawak using the polymerase chain reaction (PCR) method. A total of 107 rats, 292 soil samples, and 324 water samples were collected from April 2014 to February 2015. Pathogenic Leptospira was present in 5.6% (6/107) of rats, 11.6% (34/292) of soil samples, and 1.9% (6/324) of water samples. Intermediate Leptospira was present in 2.7% (8/292) of soil samples and 1.9% (6/324) of water samples. Saprophytic Leptospira was present in 10.3% (11/107) of rats, 1.4% (4/292) of soil samples, and 0.3% (1/324) of water samples. From this study, 76 Leptospira spp. were isolated. Based on DNA sequencing, the dominant Leptospira spp. circulating in urban areas of Sarawak are pathogenic Leptospira noguchii, intermediate Leptospira wolffii serovar Khorat, and saprophytic Leptospira meyeri, respectively. Overall, this study provided important surveillance data on the prevalence of Leptospira spp. from rats and the environment, with dominant local serovars in urban areas of Sarawak.

Leptospira interrogans and Leptospira kirschneri are the dominant Leptospira species causing human leptospirosis in Central Malaysia

“…All three species have been previously isolated and identified from humans, animals or the environment in Malaysia. L. kirschneri and L. interrogans, the most common and widely distributed Leptospira species from rodents and small mammals [13,30,[47][48][49][50][51] were identified as the main human-infecting Leptospira species in Malaysia based on our study. L. wolffii, an intermediate species was detected in the blood of two patients.…”

Critical Knowledge Gaps in Our Understanding of Environmental Cycling and Transmission of Leptospira spp

“… Leptospira bacteria have been found in water and soil samples from rural and urban settings ( 31 – 33 ), in the jungle ( 34 ), after periods of heavy rainfall ( 35 ), and even during the summer ( 36 ). In summary, Leptospira bacteria have been found in a wide variety of environments, but unfortunately, only a few systematic studies provide detail information on the positivity (prevalence) and sources of the samples analyzed ( Table 1 ) ( 17 , 28 , 29 , 32 , 33 , 37 – 52 ). Results from individual studies suggest that the likelihood of finding infectious Leptospira bacteria in the environment is site dependent, differing among regions, medium sources, and seasons.…”

Leptospira in the different ecological niches of the tribal union territory of India

“…[24]. A wide difference in the positivity (3% to 83%) of Leptospira in water samples has been reported from various environmental entities [9]. The positivity of Leptospira from water samples obtained from the South Andaman Island, India, has been reported 53.98 % from urban and 50.33 % from rural [13].…”

“…Leptospires are found in a wide variety of environmental contexts, industrialized and developing countries, and also in urban and rural contexts [4][5]. It has been also detected from different ecological niches of different geographical areas such as soil, water and urine [6][7][8][9][10][11][12][13][14][15][16][17][18][19].…”