The importance of leptospirosis in Southeast Asia.

Abstract

Abstract. The importance of leptospirosis in Southeast Asia was assessed in conjunction with other studies supported by the U.S. Naval Medical Research Unit No. 2 (US NAMRU-2), Jakarta, Republic of Indonesia. These included studies of hospital-based, acute clinical jaundice in Indonesia, Lao PDR, and Socialist Republic of Vietnam; nonmalarial fever in Indonesia; and hemorrhagic fever in Cambodia. Background prevalence estimates of leptospiral infection were obtained by a cross-sectional, community-based study in Lao PDR. Laboratory testing methods involved serology, microscopic agglutination test, and reverse-transcriptase polymerase chain reaction. Suggestive evidence of recent leptospiral infections was detected in 17%, 13%, and 3% of patients selected on the basis of non-hepatitis A through E jaundice, nonmalarial fever, and hemorrhagic fever (in the absence of acute, dengue viral infections). Leptospiral IgG antibody, reflective of prior infections, was detected in 37% of human sera, collected in Lao PDR. The predominant leptospiral serogroups identified from cases with clinical jaundice were Hurstbridge, Bataviae, and Icterohaemorrhagiae tonkini LT 96 69. Among the nonmalarial febrile cases, Bataviae was the most frequently recognized serogroup. Pyrogenes and Hurstbridge were the principal serogroups among the hemorrhagic fever case subjects. These findings further attest to the relative importance of clinical leptospirosis in Southeast Asia. The wide spectrum of clinical signs and symptoms associated with probable, acute, leptospiral infections contributes to the potential of significant underreporting.

Serological study of Leptospirosis in central Nepal

“…In Thailand, despite a decreasing male: female ratio (from a high of 9:1 in 1995 to 3:1 in 2003) male population remained to be more affected than females 27 . However, there was no difference in male: female prevalence in studies conducted in the Mekong Region in Vietnam 17,28 where exposure was more related to frequent flooding.…”

“…It is endemic in South East Asia with human infection reported throughout the region 17 . Major outbreaks were reported in recent years more notably in India, Indonesia, Sri Lanka and Thailand.…”

“…Present study shows high positivity rate in the males of age group of 16-30 followed by 31-45 years, which is similar to the report of Kuriakose et al 26 who found higher incidence of leptospiral infection in 20-40 years. Males have been shown to have a higher chance of contracting the disease suggesting a strong occupational component in transmission 17 . In Thailand, despite a decreasing male: female ratio (from a high of 9:1 in 1995 to 3:1 in 2003) male population remained to be more affected than females 27 .…”

Seroprevalence of Major Bovine-Associated Zoonotic Infectious Diseases in the Lao People's Democratic Republic

“…In the Lao PDR, leptospirosis is a known cause of acute disease (Laras et al 2002), particularly in flood-prone areas (Kawaguchi et al 2008). In this study, using the BioNote Leptospira IgM ELISA, which did not have a fixed diagnostic cutoff due to its developmental nature, Leptospira antibodies were clearly demonstrated in cattle and buffalo, even when using a conservative cutoff.…”

“…Human infection causes acute febrile illness and undulant fever, which may progress to the chronic form, resulting in musculoskeletal, cardiovascular, and central nervous system complications. Leptospirosis and Q-fever (Coxiella burnetti) are responsible for undifferentiated febrile illnesses in many rural communities in Southeast Asia, including the Lao PDR (Laras et al 2002), and Thailand (Suttinont et al 2006), and if left untreated may lead to complications. However, little is known about the role of bovines in the epidemiology of these diseases in the Lao PDR.…”