Zoonoses and Public Health最新文献

Introduction: Urban rodents are reservoirs of zoonotic pathogens, including Bartonella spp., which are transmitted by ectoparasites such as fleas. Zoonotic diseases caused by Bartonella often go undocumented due to confusing or subtle clinical symptoms, lack of awareness and poor diagnosis. This study aimed to assess the prevalence and diversity of Bartonella spp. by screening free-ranging rodents and their ectoparasites in the unique ecological settings of Alipore Railway Station, Kolkata, India. The station's high passenger traffic and proximity to food stalls create favourable conditions for rodents and fleas to thrive, increasing the risk of zoonotic transmission.

Methods: Rodents and fleas were identified by morphological features and DNA sequencing. Detection of Bartonella was carried out by DNA sequencing of citrate synthase (gltA) gene. Phylogenetic relationships among the obtained sequences were inferred through phylogenetic tree and haplotype network analyses. Q-PCR testing from human samples from the surrounding area was performed to confirm the zoonotic transfer potential.

Results: Of 60 rodents, identified as Bandicota indica 28 (46.7%) and Bandicota bengalensis 32 (53.3%), and 110 fleas (Xenopsylla cheopis) were collected. The prevalence of Bartonella infection varied across three different hosts, that is, 32/60 rodents (53.33%), 87/110 fleas (79.1%) and 4/25 human (16%). Phylogenetic analysis revealed four distinct Bartonella lineages comprising 11 novel haplotypes (H1-H11), with haplotype H4 shared between rodents, fleas and humans, indicating active and cross species transmission of Bartonella spp. Haplotype H10, identified as B. rochalimae, was a phylogenetically diverged lineage exclusively found in fleas, suggesting a potentially novel lineage.

Conclusions: The results highlight the significant public health risks posed by Bartonella spp. in densely populated urban areas, particularly in environments like railway stations where human-rodent interactions are frequent. This study underscores the necessity of integrated pest management and surveillance strategies, using molecular tools such as Q-PCR, to mitigate the risk of zoonotic disease transmission in urban settings.

Introduction: Intestinal microeukaryote parasites are major contributors to the burden of diarrhoea in humans and domestic animals, but their epidemiology in wildlife is not fully understood. We investigated the frequency, genetic diversity and zoonotic potential of protists of animal and public health significance in free-ranging grey wolf (Canis lupus) populations in south-western Europe.

Methods: Individually formed faecal samples collected from necropsied wolves or scat trails in Italy (n = 47), Portugal (n = 43) and Spain (n = 225) during the period 2011-2023 were retrospectively analysed using molecular (PCR and Sanger sequencing) methods. Complementary epidemiological data were gathered when available.

Results: Giardia duodenalis was the most frequent microeukaryote found (40.3%, 127/315; 95% CI: 34.9-46.0), followed by Cryptosporidium spp. (3.5%, 11/315; 95% CI: 1.8-6.2), Enterocytozoon bieneusi and Encephalitozoon spp. (1.6%, 5/315; 95% CI: 0.5-3.7 each). Blastocystis was not identified in any of the faecal samples analysed. Sequence analyses confirmed the presence of canine-adapted assemblage D within G. duodenalis (n = 7). Three Cryptosporidium species were identified, namely canine-adapted C. canis (n = 9), zoonotic C. parvum (n = 1) and primarily anthroponotic C.hominis (n = 1). Genotyping tools enabled the identification of subtype family XXe2 within C. canis. Among microsporidia, the canine-adapted genotype PtEb IX was identified within E. bieneusi. Two samples were confirmed as Enc. intestinalis and three more as Enc. cuniculi genotype IV. This is the first record of Enc. intestinalis and Enc. cuniculi in the grey wolf globally.

Conclusions: Silent carriage of intestinal microeukaryotes seems common in free-ranging grey wolves in southwestern Europe. Wolves can contribute to environmental contamination through the transmission stages (cysts, oocysts, spores) of species/genotypes potentially infective to humans. Individuals in close contact with wolf carcasses or their faecal material may be at potential risk of infection by microeukaryotic pathogens.

Rabies vaccination in domestic dog populations has increased globally in a bid to protect human health. Surveillance efforts, however, are inconsistent in endemic regions such as in sub-Saharan Africa, due to fragmented reporting and limited diagnostic capacity for suspected cases, limiting successful monitoring and evaluation of vaccination campaigns. Here, we conducted a pilot study aiming to strengthen rabies surveillance by combining community-based surveillance with field-based diagnostic testing in pastoral and agro-pastoral communities in central Kenya; communities which are frequently marginalised from health systems. During the 6-month pilot study, there were 14 alerts of suspected rabid dogs in the community, of which eight were tested and five diagnostically confirmed as rabid. Two positive samples processed successfully for whole genome sequencing indicated that the rabies variant circulating in central Kenya during the study period belonged to the Africa 1b subclade, which is similar to variants identified in eastern Kenya and Tanzania, suggesting regional transmission. This pilot study indicates that rabies continues to circulate in the region and that community-based surveillance, when combined with enhanced diagnostic testing, can help alleviate underreporting and guide vaccination campaigns.