Human Leptospirosis Trends: Northeast Thailand, 2001–2012

Abstract

The objective of this study was to determine the changing trend of leptospirosis over time in Thailand using two prospective hospital-based studies conducted amongst adult patients with acute undifferentiated fever (AUFI) admitted to Maharat Nakhon Ratchasima Hospital, Nakhon Ratchasima Province, Thailand between July 2001 to December 2002 and between July 2011 to December 2012. During the first period, leptospirosis (98 patients, 40%) and scrub typhus (59 patients, 24.1%) were the two major causes of AUFI. In the second period, scrub typhus (137 patients, 28.3%) was found to be more common than leptospirosis (61 patients, 12.7%). Amongst patients with leptospirosis, the proportion of male patients and the median age were similar. Leptospira interrogans serogroup Autumnalis was the major infecting serogroup in both study periods. The case fatality rate of leptospirosis was significantly higher in 2011–2012 as compared with the case fatality rate in 2001–2002 (19.7% vs. 6.3%, p < 0.001). In summary, we found that number of leptospirosis cases had decreased over time. This trend is similar to reportable data for leptospirosis complied from passive surveillance by the Ministry of Public Health, Thailand. However, the case fatality rate of severe leptospirosis has increased. Severe lung hemorrhage associated with leptospirosis remained the major cause of death.

Sociodemographic and clinical characteristics of patients infected with Leptospira spp. treated at four hospitals in Medellín, Colombia, 2008-2013

“…Este estudio incluyó 119 pacientes hospitalizados con diagnóstico de leptospirosis, en quienes se encontró una mayor frecuencia de complicaciones, especialmente falla hepática y síndrome de Weil, y una mortalidad general similar a la reportada en Colombia, pero inferior a la informada en algunas series de casos en otros países (22)(23)(24)(25)(26)(27)(28)(29). Se encontró, además, que cerca del 10 % de los pacientes no recibió tratamiento antibiótico a pesar de encontrarse hospitalizado.…”

“…Aunque la frecuencia de complicaciones fue superior a la descrita en la mayoría de las series, la mortalidad no excedió la informada en otros estudios colombianos y en el Sistema Nacional de Vigilancia en Salud Pública (1,5 a 5 %) (6,15,18,22,24,31), y fue inferior a la reportada en las series de casos en otros países (7 a 22 %) (23)(24)(25)(26)(27)(28)(29)32,33). Esta disociación entre una mayor frecuencia de complicaciones y una menor mortalidad es difícil de explicar, especialmente si se tiene en cuenta el gran número de pacientes que presentó síndrome de Weil, complicación asociada con una mayor mortalidad (32)(33)(34).…”

Retrospective screening of acute undifferentiated fever serum samples with universal flavivirus primers

“…The patients who provided 19 of the samples were subsequently shown to have dengue fever by serologic and/or NS1 screening [12]. Only 5 of these patients were amongst the PCR positive samples, showing a relatively low sensitivity for virus detection by RT-PCR in serum samples.…”

“…A confirmed diagnosis was subsequently available for 38 of the patients whose samples were included in this study, of which 19 were confirmed as dengue fever, 9 as scrub typhus and 10 as leptospirosis [12]. Dengue serology (IgG and IgM) and NS1 ELISA were undertaken in house at Siriraj hospital, Bangkok, Thailand according to established protocols [13,14].…”

“…The 274 serum samples collected on day of admission are part of a previously described prospective hospital based study on adult patients with acute undifferentiated fever undertaken at a hospital in Nakhon Ratchasima province in Northeastern Thailand [12]. Samples were collected between July 2011 and December 2012.…”