Human leptospirosis cases in Palermo Italy. The role of rodents and climate

Abstract

Many regions of the world are increasingly exposed to leptospirosis due to poverty, global warming and high urban density. Here, we report a molecular survey for pathogenic Leptospira spp. in rodents and two symptomatic human cases of leptospirosis in the city of Palermo, Italy. Four rodent species were captured in six areas of the city, and a molecular analysis for pathogenic Leptospira spp. on DNA from the kidney samples showed a different prevalence of leptospirosis in all the species of rodents. In addition, two human cases that occurred in May and October of 2009 in the city were also reported. A 67-year-old woman recovered after antibiotic treatment, whereas a 71-year-old woman did not survive. The weather during both of those times was notable for a violent cloudburst that caused street flooding. For the past several years, the incidence of leptospirosis has remained steady at 9 human cases every 10 years across the entire island of Sicily, with a population of almost 5 million inhabitants. The high prevalence of leptospirosis in rodents and the simultaneous presence of known risk factors, such as a mild/wet climate, street flooding and garbage accumulation, could explain the two cases of leptospirosis within the same city in the same year. This occurrence should raise awareness of this under-estimated zoonosis among public health authorities, especially given the potential fatality among elderly and immune-compromised individuals in urban settings in developed countries.

Hantavirus–Leptospira coinfections in small mammals from central Germany

“…In a European context, studies that screened at least 10 individuals of one species, generally reported similar prevalence for striped field mice (12.0–19.6%) [ 4 , 16 , 31 ], common voles (14.0–30.0%) [ 4 , 16 , 31 – 33 ] and field voles (12.0–30.1%) [ 4 , 31 ]. For the yellow-necked mouse only a study in Serbia detected a higher average prevalence with 34.3% [ 33 ], for the wood mouse studies detected similar average prevalence with 15.4% and 18.0% [ 31 , 34 ] and for bank voles our study is in line with a previously published prevalence [ 4 , 31 ].…”

Prevalence and risk factors of Leptospira infection in urban brown rats (Rattus norvegicus), Vienna, Austria

“…More generally, the incidence of human cases of leptospirosis is rising in Europe (European Centre for Disease Prevention and Control 2018) as well as the rate of (peri-) urban transmission (Dupouey et al 2014). The increase of the leptospirosis burden in European countries is most likely exacerbated by climate change (global warming and increased frequency and severity of extreme weather events) (Lau 2010), human population growth (Lau 2010), increasing urbanisation (Minter et al 2018), increasing expansion of urban rodents (Boey et al 2019;Dupouey et al 2014;Vitale et al 2018) and other wildlife reservoirs (Baldi et al 2019;Jansen et al 2007), and rise in international travels (Pijnacker et al 2017). Rat population control through culling appears inefficient for reducing the risk of Leptospira transmission to humans (Lee et al 2018).…”

Presence of pathogenic Leptospira spp. in the reproductive system and fetuses of wild boars (Sus scrofa) in Italy

“…Leptospira kirschneri infection seems to be prevalent in testicles and epididymides, while Leptospira interrogans is present in female genital organs. Based on the serovars more often detected in Italy by cultural examination or serology [46][47][48][49][50][51][52], and the rare seropositivity for other serovars [53][54][55], it is likely that the detected L. kirschneri belonged to the serogroup Grippotyphosa. In this study, L. kirschneri infection was only observed in testicles and epididymides, and this could hypothesize this genomospecies as more often associated with the male reproductive system.…”