Weil's disease in a young homeless man living in Lisbon

Leptospira spp. Antibody Seroprevalence in Stray Dogs and Cats: A Study in Milan, Northern Italy

Leptospirosis is a widespread zoonosis recognised as a re-emerging infectious disease in both humans and dogs, yet the actual seroprevalence of Leptospira in pets in Italy is relatively unknown. The aim of this study was to evaluate Leptospira antibody prevalence in dogs and cats from a shelter by the microscopic agglutination test (MAT), the gold standard test in leptospiral serology, and to assess risk factors for Leptospira infection. This seroepidemiological study investigated the prevalence of leptospiral antibodies in a cohort of 106 dogs and 51 cats housed in a municipal shelter in Milan. Blood samples were collected from the animals during two sampling periods: spring/summer 2014 and autumn/winter 2016/2017. Eight serogroups were evaluated: L. Australis, L. Ballum, L. Canicola, L. Grippotyphosa, L. Icterohaemorrhagiae, L. Pomona, L. Sejroe, and L. Tarassovi. Antibody titres ranged from 1:100 to 1:6400. The results indicated that 21.7% of dogs had antibodies against serogroups L. Icterohaemorrhagiae and L. Australis, making them the most often found. Conversely, none of the cats showed any presence of antibodies. Seropositivity was higher in the spring/summer period (32.7%) than in autumn/winter (11.1%), and no statistically significant results were found regarding sex or age. These findings underscore the importance of ongoing serological surveillance and biosecurity measures in shelter environments to mitigate the zoonotic risk posed by leptospirosis.

Invisible struggles: WASH insecurity and implications of extreme weather among urban homeless in high-income countries - A systematic scoping review

This paper aims to provide a deeper understanding of the water-, sanitation- and hygiene (WASH)-related insecurities that people experiencing homelessness in urban areas of high-income countries (HIC) are facing, and how these insecurities are further complicated during extreme weather events. While limited recent research has looked into WASH among people experiencing homelessness in HICs, and while some work has considering the implications of climate change on WASH and health, the nexus of WASH, extreme weather events and homelessness in HICs have not been studied thus far. We conducted the first systematic scoping review of peer-reviewed literature on this nexus, which is understudied and marked by complexity, involving a range of systems and forms of impact. A total of 50 publications were included in our analysis. We found that public facilities like drinking water fountains, toilets, handwashing facilities, and showers are scarce, frequently unavailable, often pose safety and cleanliness issues, and access to non-public facilities may be cost-prohibitive for homeless populations. Consequently, people experiencing homelessness, including those sleeping rough, in encampments, or shelters, are often forced to limit drinking water consumption, forego healthy hygiene behaviours, and resort to open urination and defecation, all of which carry health risks. Extreme weather events, like heatwaves, extreme cold, heavy rain and flooding exacerbate challenges for people experiencing homelessness, further complicating their access to WASH, and reducing the ability of service providers to deliver extra relief, creating a dual WASH and health burden. Our review highlights that the Human Right to Water and Sanitation is not met for people experiencing homelessness in urban areas of high-income countries, with women emerging as one of the most vulnerable subgroups. It reveals that the impact of certain WASH issues (e.g. drinking water) on homeless populations are better understood than others (e.g. waste), and, similarly, the effects of certain extreme weather events (e.g. heatwaves) on the health and WASH conditions of people experiencing homelessness are better understood than others (e.g. flooding). Data gaps and the lack of information on limited WASH access and health circumstances of people experiencing homelessness, further minimize their representation and consequently impose obstacles to improve their situation. Based on our analysis, we established a framework which operationalizes the nexus of WASH, extreme weather events and homelessness. This framework improves our understanding of the underlying complexities at the intersection of these three issues and provides a foundation for enhanced preparedness and health-oriented planning.

One health approach on serosurvey of anti-Leptospira spp. in homeless persons and their dogs in South Brazil

Although leptospirosis has been described as a worldwide bacterial zoonosis primarily affecting vulnerable populations, to date no study has focused on concomitant serosurvey of homeless persons and their dogs. The aim of the present study was, to use a One Health approach to serologically assess homeless persons and their dogs in 3 major cities of south Brazil (São Paulo, Curitiba, and Foz do Iguaçu). Environmental information was obtained with an epidemiological questionnaire given to all participants. A total of 200 human and 75 dog samples were tested for anti-Leptospira spp. antibodies to thirty different serovars using the microscopic agglutination test. None of the homeless persons were positive while 5 of the 75 (6.7%) dogs were positive. Among homeless population, 89% (177 of 200) were male, 61% (122 of 200) self-declared Non-white, and 67% (134 of 200) were educated up to the 8th school grade. Lower exposure of homeless persons to Leptospira spp. in the present study when compared to other vulnerable populations (slum and low-income residents) may be result of less direct exposure as they are able to rapidly change locations in response to flooding events. In addition, these results may reflect the effectiveness of a specific healthcare service provided to people living in the streets in the 3 cities. While dogs may be used as environmental sentinels for leptospirosis, the low seropositivity results found in this report may indicate low transmission risk to homeless owners in direct daily contact with their dogs.

A global one health perspective on leptospirosis in humans and animals

Leptospirosis is a quintessential one health disease of humans and animals caused by pathogenic spirochetes of the genus Leptospira. Intra- and interspecies transmission is dependent on 1) reservoir host animals in which organisms replicate and are shed in urine over long periods of time, 2) the persistence of spirochetes in the environment, and 3) subsequent human-animal-environmental interactions. The combination of increased flooding events due to climate change, changes in human-animal-environmental interactions as a result of the pandemic that favor a rise in the incidence of leptospirosis, and under-recognition of leptospirosis because of nonspecific clinical signs and severe signs that resemble COVID-19 represents a "perfect storm" for resurgence of leptospirosis in people and domestic animals. Although often considered a disease that occurs in warm, humid climates with high annual rainfall, pathogenic Leptospira spp have recently been associated with disease in animals and humans that reside in semiarid regions like the southwestern US and have impacted humans that have a wide spectrum of socioeconomic backgrounds. Therefore, it is critical that physicians, veterinarians, and public health experts maintain a high index of suspicion for the disease regardless of geographic and socioeconomic circumstances and work together to understand outbreaks and implement appropriate control measures. Over the last decade, major strides have been made in our understanding of the disease because of improvements in diagnostic tests, molecular epidemiologic tools, educational efforts on preventive measures, and vaccines. These novel approaches are highlighted in the companion Currents in One Health by Sykes et al, AJVR, September 2022.

Autochthonous human and animal leptospirosis, Marseille, France

Autochtonous leptospirosis is an emerging zoonotic disease in Europe, particularly in France. We report a case of leptospirosis in a 36 year-old man, who is a recently arrived migrant from Tunisia and lives in a squat. He suffered from pulmonary and neurological involvement as well as hepatitis. Seven rats (Rattus norvegicus) were trapped in the squat where the patient lived. Leptospira spp. DNA was detected in the kidney of one rat, highlighting the most likely source of contamination. In addition to the classic recreational or professional exposure to fresh water and practice of outdoor sports as a source of leptospirosis contamination, unhealthy living conditions (homeless or squatting) and therefore frequent exposure to rats, are another risk factor for leptospirosis in Europe.