Leptospirosis is a global zoonotic disease caused by pathogenic bacteria of the genus Leptospira. We sought to determine if rodents in U.S. Virgin Islands (USVI) are carriers of Leptospira. In total, 140 rodents were sampled, including 112 Mus musculus and 28 Rattus rattus. A positive carrier status was identified for 64/140 (45.7%); 49 (35.0%) were positive by dark-field microscopy, 60 (42.9%) by culture, 63 (45.0%) by fluorescent antibody testing, and 61 (43.6%) by real-time polymerase chain reaction (rtPCR). Molecular typing indicated that 48 isolates were L. borgpetersenii and 3 were L. kirschneri; the remaining nine comprised mixed species. In the single culture-negative sample that was rtPCR positive, genotyping directly from the kidney identified L. interrogans. Serotyping of L. borgpetersenii isolates identified serogroup Ballum and L. kirschneri isolates as serogroup Icterohaemorrhagiae. These results demonstrate that rodents are significant Leptospira carriers and adds to understanding the ecoepidemiology of leptospirosis in USVI.

The first documented human leptospirosis cases in the U.S. Virgin Islands (USVI) occurred following 2017 Hurricanes Irma and Maria. We conducted a representative serosurvey in USVI to estimate the seroprevalence and distribution of human leptospirosis and evaluate local risk factors associated with seropositivity. A stratified, two-stage cluster sampling design was used and consisted of three island strata and random selection of census blocks and then households. All eligible members of selected households were invited to participate (≥5 years old, resided in USVI ≥6 months and ≥6 months/year). Household and individual-level questionnaires were completed, and serum collected from each enrolled individual. Microscopic agglutination test serology was conducted, and bivariate and logistic regression analyses completed to identify risk factors for seropositivity. In March 2019, 1,161 individuals were enrolled from 918 households in St. Croix, St. Thomas, and St. John. The territory-wide weighted seroprevalence was 4.0% (95% CI:2.3–5.7). Characteristics/exposures independently associated with seropositivity using logistic regression included contact with cows (OR: 39.5; 95% CI: 9.0–172.7), seeing rodents/rodent evidence or contact with rodents (OR: 2.6; 95% CI: 1.1–5.9), and increasing age (OR: 1.02; 95% CI: 1.002–1.04); full or partial Caucasian/White race was negatively correlated with seropositivity (OR: 0.02, 95% CI: 0.04–0.7). Bivariate analysis showed self-reported jaundice since the 2017 hurricanes (pRR: 5.7; 95% CI: 1.0–33.4) was associated with seropositivity and using a cover/lid on cisterns/rainwater collection containers (pRR: 0.3; 95% CI: 0.08–0.8) was protective against seropositivity. Leptospirosis seropositivity of 4% across USVI demonstrates an important human disease that was previously unrecognized and emphasizes the importance of continued leptospirosis surveillance and investigation. Local risk factors identified may help guide future human and animal leptospirosis studies in USVI, strengthen leptospirosis public health surveillance and treatment timeliness, and inform targeted education, prevention, and control efforts. We established that in 2019, four percent of the population in the U.S. Virgin Islands (USVI) had evidence of previous exposure to Leptospira bacteria. There were no human cases of leptospirosis documented in USVI before the 2017 hurricanes, however due to the prevalence of the disease in other Caribbean localities, the post-hurricane cases, and the evidence of exposure demonstrated in this investigation, it is likely that leptospirosis has been a previously unrecognized problem in the territory. We demonstrated that contact with rodents or their body fluids or seeing rodents/evidence of rodents, contact with cows, increasing age, and not being part or full Caucasian/White race are independently associated with previous exposure to Leptospira spp. in USVI. These findings highlight the importance of continuing leptospirosis surveillance in USVI, considering leptospirosis as a diagnosis in patients with acute febrile illness and/or compatible exposures, and further investigating the epidemiology, ecology, and clinical features of leptospirosis in USVI. Our investigation also supports the need to investigate leptospirosis, and consider it a potential diagnosis, in locations with environmental conditions the bacteria favor (tropical and subtropical areas), even if leptospirosis has not been previously documented in those areas, and especially if it has not been previously investigated.

Background: Uganda has experienced seven Ebola Virus Disease (EVD) outbreaks and four Marburg Virus Disease (MVD) outbreaks between 2000 and 2019. We investigated the seroprevalence and risk factors for Marburg virus and ebolaviruses in gold mining communities around Kitaka gold mine in Western Uganda and compared them to non-mining communities in Central Uganda. Methods: A questionnaire was administered and human blood samples were collected from three exposure groups in Western Uganda (gold miners, household members of miners, non-miners living within 50 km of Kitaka mine). The unexposed controls group sampled was community members in Central Uganda far away from any gold mining activity which we considered as low-risk for filovirus infection. ELISA serology was used to analyse samples, detecting IgG antibodies against Marburg virus and ebolaviruses (filoviruses). Data were analysed in STATA software using risk ratios and odds ratios. Results: Miners in western Uganda were 5.4 times more likely to be filovirus seropositive compared to the control group in central Uganda (RR = 5.4; 95% CI 1.5–19.7) whereas people living in high-risk areas in Ibanda and Kamwenge districts were 3.6 more likely to be seropositive compared to control group in Luweeero district (RR = 3.6; 95% CI 1.1–12.2). Among all participants, filovirus seropositivity was 2.6% (19/724) of which 2.3% (17/724) were reactive to Sudan virus only and 0.1% (1/724) to Marburg virus. One individual seropositive for Sudan virus also had IgG antibodies reactive to Bundibugyo virus. The risk factors for filovirus seropositivity identified included mining (AOR = 3.4; 95% CI 1.3–8.5), male sex (AOR = 3.1; 95% CI 1.01–9.5), going inside mines (AOR = 3.1; 95% CI 1.2–8.2), cleaning corpses (AOR = 3.1; 95% CI 1.04–9.1) and contact with suspect filovirus cases (AOR = 3.9, 95% CI 1.04–14.5). Conclusions: These findings indicate that filovirus outbreaks may go undetected in Uganda and people involved in artisan gold mining are more likely to be exposed to infection with either Marburg virus or ebolaviruses, likely due to increased risk of exposure to bats. This calls for active surveillance in known high-risk areas for early detection and response to prevent filovirus epidemics.

Introduction: Leptospirosis is endemic to Puerto Rico, affecting people through seasonal increases and outbreaks. This report describes the diagnostic approach and clinical characteristics of leptospirosis cases identified through active undifferentiated acute febrile illness (UAFI) surveillance in Puerto Rico. Materials and Methods: From 2019 to 2021, active surveillance was conducted in four emergency departments (EDs), with standardized recruitment of patients aged ≥ 5 years, presenting with fever or a history of fever of unknown origin within the past two weeks. Additional cases were recruited from referrals of patients with positive leptospirosis diagnostic tests routinely ordered by clinicians. All enrolled patients were subject to a standardized diagnostic algorithm using PCR and serology to identify probable and confirmed leptospirosis cases. Patient data were collected from electronic medical records and interviews. Results: Leptospirosis was diagnosed in 4% of 406 ED‐enrolled UAFI patients, eight confirmed and eight probable cases. Referrals resulted in the identification of 12 routinely detected cases (five confirmed and seven probable). Of the 28 cases, 71% were ≤ 7 days post onset, 71% were male, average age was 43 years old, and the most common presentations included lower back pain (82%), headache (75%), fatigue (71%), vomiting (71%), myalgia (71%), and calf pain (64%). Common clinical laboratory findings were elevated AST (78%), hyperglycemia (74%), thrombocytopenia (48%), proteinuria (62%), and hematuria (62%). Classification of four isolates identified L. interrogans serovar Icterohaemorrhagiae/Copenhageni ( n = 2), L. borgpetersenii serovar Ballum/Guangdong, and L. kirschneri (no serovar match). All but one of the leptospirosis cases met the current Council of State and Territorial Epidemiologists’ definition for clinical compatibility with leptospirosis. Hemorrhagic symptoms and acute kidney injury with jaundice were associated with being a leptospirosis case. Conclusions: These findings underscore the role of leptospirosis among febrile illnesses in Puerto Rico, the need for increased awareness to optimize diagnosis and treatment, and further research to improve prevention and intervention strategies.

Leptospirosis is a zoonotic disease of global importance that significantly impacts human health and the livestock industry. In Puerto Rico, outbreaks of leptospirosis in humans have been associated with hurricanes and subsequent flooding events. Rodent species in Puerto Rico and feral swine in the continental United States have been implicated as reservoir hosts for Leptospira species and serogroups, with the possibility of transmitting the pathogen to humans. In this cross‐sectional investigation, we collected samples from 670 animals, including 375 feral swine, 168 transitional swine, 120 dairy cattle, six beef cattle, and one small ruminant to assess Leptospira spp. exposure and infection in specific regions of Puerto Rico. Of all animals sampled and tested, 55.82% ( n = 374) had a positive result to at least one of the following leptospirosis tests performed: microscopic agglutination test (MAT), polymerase chain reaction (PCR), fluorescent antibody test (FAT), and/or culture. Of all animals from which serum samples were tested, 75.90% ( n = 126) of transitional swine, 78.72% ( n = 37) of dairy cattle, 100% ( n = 4) of beef cattle, and 53.13% ( n = 195) of feral swine had detectable Leptospira antibodies on MAT. Of all animals from which urine samples were collected and tested on either lipL32 PCR or FAT, 0% of transitional swine, 22.86% ( n = 24) of dairy cattle, 16.67% ( n = 1) of beef cattle, and 1.71% ( n = 2) of feral swine tested positive for Leptospira species on one or both of these tests. L. borgpetersenii serogroup Sejroe serovar Hardjo was isolated from the urine of two dairy cows, and L. santarosai serogroup Pyrogenes was isolated from the urine of another dairy cow. The findings of this investigation provide valuable information on the circulating Leptospira species, serogroups, and serovars in domestic livestock and feral swine in specific regions of Puerto Rico and will further inform human and animal disease prevention, preparedness, and response.