Serosurvey of leptospirosis in feral hogs (Sus scrofa) in Florida.

Leptospira is a global pathogen of emerging public health importance in both developing and industrialized nations and can infect almost all mammalian species, including humans. As suburbanization and the popularity of outdoor recreational activities increases, so do human-wildlife and companion animal-wildlife interfaces. Florida offers a tropical climate favorable for outdoor activities and a semirural landscape that sustains an abundant feral hog population. Because no survey ofleptospirosis in feral hogs (Sus scrofa) in Florida has been published to our knowledge, we sought to establish preliminary seroprevalence ofleptospirosis exposure in feral hogs in Florida. Blood samples were collected opportunistically from 158 male and 166 female feral hogs taken at managed hunts and by permitted trappers in the northern, central, and southern regions of Florida. Samples were then analyzed using the microscopic agglutination test (MAT) for antibody titers to 20 Leptospira serovars representing 17 serogroups. A titer of > 1:100 was considered positive; 33% (107/324 total samples) were positive to at least one serovar, and 46% of those were positive to multiple serovars. Antibodies to L. interrogans serovar Bratislava strain Jez Bratislava (serogroup Australis) was the most common, with 18% (58/324) testing positive for antibodies. These initial data indicate that there is a significant possibility of feral hogs having a larger role in the complex etiology of leptospirosis in Florida than historically estimated and that further investigation is warranted.

Leptospirosis and human immunodeficiency virus co-infection among febrile inpatients in northern Tanzania.

BACKGROUND: Leptospirosis and human immunodeficiency virus (HIV) infection are prevalent in many areas, including northern Tanzania, yet little is known about their interaction. METHODS: We enrolled febrile inpatients at two hospitals in Moshi, Tanzania, over 1 year and performed HIV antibody testing and the microscopic agglutination test (MAT) for leptospirosis. Confirmed leptospirosis was defined as ≥ four-fold rise in MAT titer between acute and convalescent serum samples, and probable leptospirosis was defined as any reciprocal MAT titer ≥ 800. RESULTS: Confirmed or probable leptospirosis was found in 70 (8.4%) of 831 participants with at least one serum sample tested. At total of 823 (99.0%) of 831 participants had HIV testing performed, and 203 (24.7%) were HIV infected. Among HIV-infected participants, 9 (4.4%) of 203 had confirmed or probable leptospirosis, whereas among HIV-uninfected participants 61 (9.8%) of 620 had leptospirosis. Leptospirosis was less prevalent among HIV-infected as compared to HIV-uninfected participants [odds ratio (OR) 0.43, p=0.019]. Among those with leptospirosis, HIV-infected patients more commonly presented with features of severe sepsis syndrome than HIV-uninfected patients, but differences were not statistically significant. Among HIV-infected patients, severe immunosuppression was not significantly different between those with and without leptospirosis (p=0.476). Among HIV-infected adolescents and adults, median CD4 percent and median CD4 count were higher among those with leptospirosis as compared to those with other etiologies of febrile illness, but differences in CD4 count did not reach statistical significance (p=0.015 and p=0.089, respectively). CONCLUSIONS: Among febrile inpatients in northern Tanzania, leptospirosis was not more prevalent among HIV-infected patients. Although some indicators of leptospirosis severity were more common among HIV-infected patients, a statistically significant difference was not demonstrated. Among HIV-infected patients, those with leptospirosis were not more immunosuppressed relative to those with other etiologies of febrile illness.

Acute febrile illness surveillance in a tertiary hospital emergency department: comparison of influenza and dengue virus infections.

In 2009, an increased proportion of suspected dengue cases reported to the surveillance system in Puerto Rico were laboratory negative. As a result, enhanced acute febrile illness (AFI) surveillance was initiated in a tertiary care hospital. Patients with fever of unknown origin for 2-7 days duration were tested for Leptospira, enteroviruses, influenza, and dengue virus. Among the 284 enrolled patients, 31 dengue, 136 influenza, and 3 enterovirus cases were confirmed. Nearly half (48%) of the confirmed dengue cases met clinical criteria for influenza. Dengue patients were more likely than influenza patients to have hemorrhage (81% versus 26%), rash (39% versus 9%), and a positive tourniquet test (52% versus 18%). Mean platelet and white blood cell count were lower among dengue patients. Clinical diagnosis can be particularly difficult when outbreaks of other AFI occur during dengue season. A complete blood count and tourniquet test may be useful to differentiate dengue from other AFIs.

Leptospirosis among hospitalized febrile patients in northern Tanzania.

We enrolled consecutive febrile admissions to two hospitals in Moshi, Tanzania. Confirmed leptospirosis was defined as a ≥ 4-fold increase in microscopic agglutination test (MAT) titer; probable leptospirosis as reciprocal MAT titer ≥ 800; and exposure to pathogenic leptospires as titer ≥ 100. Among 870 patients enrolled in the study, 453 (52.1%) had paired sera available, and 40 (8.8%) of these met the definition for confirmed leptospirosis. Of 832 patients with ≥ 1 serum sample available, 30 (3.6%) had probable leptospirosis and an additional 277 (33.3%) had evidence of exposure to pathogenic leptospires. Among those with leptospirosis the most common clinical diagnoses were malaria in 31 (44.3%) and pneumonia in 18 (25.7%). Leptospirosis was associated with living in a rural area (odds ratio [OR] 3.4, P < 0.001). Among those with confirmed leptospirosis, the predominant reactive serogroups were Mini and Australis. Leptospirosis is a major yet underdiagnosed cause of febrile illness in northern Tanzania, where it appears to be endemic.

Leptospirosis as a cause of fever in urban Bangladesh.

We tested paired sera from 584 febrile persons in an low-income urban community in Bangladesh for evidence of Leptospira infection. A total of 8.4% of the persons met criteria for definite or probable infection. Persons with leptospirosis were older than those with undifferentiated fever in this population. The dominant infecting serogroups in Bangladesh differed from serogroups commonly reported in nearby regions.