Epidemiology of human leptospirosis in Malaysia, 2004–2012

Abstract

Leptospirosis is an emerging disease, especially in countries with a tropical climate such as Malaysia. A dramatic increase in the number of cases has been reported over the last decade; however, information on the epidemiological trends of this disease is lacking. The objective of this study is to provide an epidemiological description of human leptospirosis cases over a 9-year period (2004-2012) and disease relationship with meteorological, geographical, and demographical information. A retrospective study was undertaken to describe the patterns of human leptospirosis cases and their association with intrinsic (sex, age, and ethnicity) and extrinsic (location, rainfall, and temperature) factors. Data was grouped according to age, sex, ethnicity, seasonality and geographical distribution, and analyzed using statistical tools to understand the influence of all the different factors on disease incidence. A total of 12,325 cases of leptospirosis were reported between 2004 and 2012 with an upward trend in disease incidence, with the highest in 2012. Three hundred thirty-eight deaths were reported with an overall case fatality rate of 2.74%, with higher incidence in males (9696; 78.7%) compared with female patients (2629; 21.3%), and overall male to female ratio of 3.69:1. Patients aged cohorts between 30-39 years old (16.22 per 100,000 population) had the highest disease incidence while the lowest incidence occurred between <1 to 9 years old (3.44 per 100,000 population). The average incidence was highest amongst Malays (10.97 per 100,000 population), followed by Indians (7.95 per 100,000 population). Stratification according to geographical distribution showed that the state of Malacca had the highest average disease incidence (11.12 per 100,000 population) followed by Pahang (10.08 per 100,000 population). The states of Terengganu, Kelantan, and Perak recorded similar rates of incidence (≈8.00 per 100,000 population), while Johor with the least number of reported cases (1.80 per 100,000 population). Positive relationships were recorded between the number of reported cases with the number of raining days per month and monthly average temperature (p-value<0.05). However, no significant association was noted between rainfall volume and number of reported Leptospirosis cases. This collaborative efforts between medical, academic and governmental institutions has enabled the construction of this comprehensive database that is essential to understand the disease trends in Malaysia and add insights into the prevention and control of this disease.

The epidemiology, characteristics and outbreaks of human leptospirosis and the association with animals in Taiwan, 2007–2014: A nationwide database study

“…Male gender and high‐risk occupations (farmer, animal husbandry or veterinarian) are more common in LS than non‐confirmed LS (Table ), which is similar to previous studies (Benacer et al, ; Goris, Boer, Duarte, Kliffen, & Hartskeerl, ; Jansen, Stark, Schneider, & Schoneberg, ; Traxler, Callinan, Holman, Steiner, & Guerra, ; Wuthiekanun et al, ). The predominance in men could be related to more involvement in high‐risk occupations and outdoor activities, which might result in more exposure to the environment contaminated with leptospires.…”

Seroprevalence of leptospiral antibodies among market workers and food handlers in the central state of Malaysia

“…It is considered as the most widespread re-emerging zoonotic disease in the world [1][2][3]. Humans are infected via direct contact with contaminated urine, blood or infected tissue from animal reservoirs, or indirectly through contaminated water and soil [4]. Risk of leptospirosis infection in humans is related to the environment, the medium of transmission and at-risk activity [4].…”

“…Humans are infected via direct contact with contaminated urine, blood or infected tissue from animal reservoirs, or indirectly through contaminated water and soil [4]. Risk of leptospirosis infection in humans is related to the environment, the medium of transmission and at-risk activity [4]. Clinical manifestations of leptospirosis vary from asymptomatic to severe and are potentially fatal [4,5].…”

“…Risk of leptospirosis infection in humans is related to the environment, the medium of transmission and at-risk activity [4]. Clinical manifestations of leptospirosis vary from asymptomatic to severe and are potentially fatal [4,5].…”

Development and evaluation of an immunochromatographic assay to detect serum anti-leptospiral lipopolysaccharide IgM in acute leptospirosis

“…The global importance of this infectious disease has been evidenced by an approximation of 500,000 cases reported annually around the globe with a rising trend 2–9 . In addition, the majority of these cases have severe clinical manifestations and poor outcome due to a lack of rapid test, which is sensitive and effective enough for early detection that prompts proper intervention 10–12 .…”