Vector borne and zoonotic diseases最新文献

Background: Bats act as reservoirs for a variety of zoonotic viruses, sometimes leading to spillover into humans and potential risks of global transmission. Viral shedding from bats is an essential prerequisite to bat-to-human viral transmission and understanding the timing and intensity of viral shedding from bats is critical to mitigate spillover risks. However, there are limited investigations on bats' seasonal viral shedding patterns and their related risk factors. We conducted a comprehensive review of longitudinal studies on bat viruses with spillover potential to synthesize patterns of seasonal viral shedding and explore associated risk factors. Methods: We extracted data from 60 reviewed articles and obtained 1085 longitudinal sampling events. We analyzed viral shedding events using entropy values to quantitatively assess whether they occur in a consistent, pulsed pattern in a given season. Results: We found that clear seasonal shedding patterns were common in bats. Eight out of seventeen species-level analyses presented clear seasonal patterns. Viral shedding pulses often coincide with bats' life cycles, especially in weaning and parturition seasons. Juvenile bats with waning maternal antibodies, pregnant bats undergoing immunity changes, and hibernation periods with decreased immune responses could be potential risk factors influencing seasonal shedding patterns. Conclusion: Based on our findings, we recommend future longitudinal studies on bat viruses that combine direct viral testing and serological testing, prioritize longitudinal research following young bats throughout their developmental stages, and broaden the geographical range of longitudinal studies on bat viruses based on current surveillance reports. Our review identified critical periods with heightened viral shedding for some viruses in bat species, which would help promote efforts to minimize spillovers and prevent outbreaks.

Background: Dengue virus (DENV) infection, caused by serotypes DENV 1-4, represents a significant global public health challenge, with no antiviral drugs currently available for treatment. The host Protein kinase B (AKT) signaling pathway is crucial for DENV infection, presenting a potential target for antiviral drug development. Objective: This study aimed to evaluate the antiviral activity of kinase inhibitors that target the AKT pathway, focusing on the compound AT13148. Methods: A mini-screening was conducted to identify kinase inhibitors with antiviral properties against DENV-2. The effects of AT13148 on viral RNA replication and translation were assessed in a dose- and time-dependent manner following DENV-2 entry. The mechanism of action was further investigated by evaluating the impact of AT13148 on AKT kinase activity and phosphorylation status. Results: AT13148 exhibited potent antiviral activity against DENV-2, significantly inhibiting viral RNA replication and translation post-entry. The compound was found to inhibit AKT kinase activity through hyperphosphorylation. Conclusion: The findings indicate that AT13148 effectively targets the AKT pathway, demonstrating potential as an antiviral therapeutic against DENV-2 by interfering with the virus's post-entry processes. Further in vivo studies are warranted to assess the efficacy of AT13148 in controlling DENV infection.

Introduction: Lyme disease (LD) surveillance yields useful information to monitor the disease trends and spatial distribution. However, due to several factors, the Manitoba Health surveillance system, as with other systems, could be subject to underreporting. Objectives: To estimate the number and incidence of clinician-diagnosed LD over the study period in Manitoba, describe the epidemiology of clinician-diagnosed LD, and compare the findings with Manitoba Health LD surveillance data during the same period to estimate the extent of underreporting. Methods: A retrospective analysis of administrative health data was performed to calculate the number and incidence of clinician-diagnosed LD from 2009 to 2018 in Manitoba and describe the epidemiological characteristics using the International Classification of Diseases, Tenth and Ninth Revision (ICD-10-CA and ICD-9-CM) codes, and antimicrobial drug prescriptions. Conclusion: Of the 1,629,698 registrants within the Manitoba Health Insurance Registry followed over 10 years, 1658 LD events were identified. Most of the cases occurred from May to July and corresponded to the peak activity of the nymphal stage of the blacklegged tick in the province. LD events presented a bimodal distribution with a peak in children between 5 and 9 years of age for both sexes, and a peak in adults from 65 to 84 and from 50 to 74, respectively, for males and females. We estimated that an average of 165 LD events occurred annually in Manitoba (mean annual incidence of 10.17 per 100,000 population), compared with 30 cases per year reported in the surveillance system; therefore, the LD surveillance yields an important underreporting.

Background: Rats are an important reservoir animal for several zoonotic pathogens worldwide, including hantaviruses and Leptospira spp., which are the causative agents of hemorrhagic fever with renal syndrome, hantavirus cardiopulmonary syndrome, and leptospirosis. Although a previous study indicated a high frequency of antihantaviral antibodies in patients with acute fever in Indonesia, circulating hantaviruses and their reservoir animals in the country remain limited. Materials and Methods: The presence of hantavirus in rats captured in the urban area of Bogor, Indonesia, from which Leptospira spp. were isolated using PCR, followed by DNA sequencing. Immunohistochemical analyses were performed to detect hantaviral and leptospiral antigens in rat kidney tissues. Results: Seoul of Orthohantavirus seoulense (SEOV) RNA was detected from 24 of 80 Rattus norvegicus (30%). SEOV and Leptospira coinfection was detected in 10 of 80 rats (12.5%). Immunohistochemistry revealed that hantavirus antigens were positively stained in the interstitial capillaries and cells, whereas Leptospira antigens were stained in the luminal side of the renal tubules. Conclusion: This study revealed a high prevalence of SEOV and SEOV and Leptospira coinfection among rats in the urban areas of Bogor, Indonesia, indicating a potential risk of rat-borne zoonotic diseases in the area.

Background: The genus Bartonella is composed of Gram-negative, fastidious, facultative intracellular bacteria that can cause bacteremia in mammals and various disorders in humans. Rodents have been reported as reservoirs of more than 30 Bartonella species, seven of which cause zoonotic infections. Materials and Methods: In the present study, the isolation of Bartonella sp. was attempted from 150 spleen samples from 13 rodent species (mostly Apodemus species) from three geographically different regions in Turkey. Results: Bartonella sp. was successfully isolated from 65 of these 150 samples (43%). The prevalences of Bartonella sp. in tested rodents in the regions of Giresun, Yozgat, and Burdur were 68%, 44%, and 16%, respectively. Using polymerase chain reaction/sequence analysis of the citrate synthase-coding gene (gltA), Bartonellaisolates were classified seven species including B. taylorii, B. grahamii, B. birtlesii, B. mastomydis, and three putatively new Bartonella species. We performed further identification techniques for one of the three Bartonella species that were different from the validated Bartonella species according to the gltA sequence analysis. Conclusion: Here, we report the genomic and phenotypic characterization of Bartonella sp. strain G70 that was isolated from the splenic tissue of an Apodemus uralensis (Pallas 1881), the Ural field mouse, captured in the Giresun region of northeastern Turkey. Bartonella sp. strainG70 (RSKK 22001) was characterized by whole genome and partial gene (gltA, 16S ribosomal RNA) sequencing and comparison, scanning electron microscopy, biochemical tests, and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. This novel Bartonella is a Gram-negative, rod-shaped bacterium and has neither flagella nor pili. The genome from strain G70 was 1,606,969-bp-long with a G + C content of 35.7%. Bartonella rochalimae was found to be the closest phylogenetic relative of strain G70 (OrthoANI = 90.5%, digital DNA-DNA hybridization = 41.4%). We therefore propose that this new species be named Bartonella bilalgolemii sp. nov. with strain G70^T as the type strain.

Background: Brucellosis is a major global public health problem. Brucellosis usually coinfects with zoonoses because of their similar reservoir and infection routes. Materials and Methods: Here, we present a patient who was diagnosed with coinfecting with liver cyst and brucellosis. Results: A 57-year-old female farmer was hospitalized with right hip joint pain approximately 4 weeks earlier. The patient reported a history of hydatid cysts and a family history of brucellosis. Abdominal computerized tomography and ultrasonography revealed a liver hydatid cyst. The standard agglutination test titer of Wright's test was 1:100. Computerized tomography and magnetic resonance imaging revealed brucellosis hip arthritis. The patient was treated with a combination of doxycycline, rifampicin, and cefotaxime. The symptoms immediately improved. The patient was well and asymptomatic during the 6-month follow-up. We reviewed the literature on other zoonoses superinfection with brucellosis. Conclusion: Brucellosis coinfects with multiple zoonosis organisms and poses a serious health threat to humans. Awareness of possible brucellosis coinfection with other zoonoses, especially professionally exposed persons in endemic regions, is warranted.

Background: Soft ticks (Family: Argasidae) are vectors of relapsing fever Borrelia in the United States and are potential vectors of African swine fever virus, a pathogen that could have a devastating effect on the U.S. swine industry if introduced to the U.S. mainland. Much of the tick-borne disease research in the U.S. focuses on hard ticks, and less is known about the ecology of soft ticks. Some soft tick species found in the southern U.S. have a wide host range and may feed on cattle, swine, native and exotic ungulates, small mammals, reptiles, and humans. Because the feeding habit of most soft tick species involves taking short, repeated blood meals that may include multiple host species, pathogen transmission among hosts is a concern both for human and animal health. Materials and Methods: Sampling was carried out at four locations in south Texas using dry ice traps placed in or near animal burrows and other sheltering cracks and crevasses that may provide refuge for soft ticks. Collected ticks were identified and subsequently screened for Rickettsia and Borrelia species and for host bloodmeal detection using conventional polymerase chain reaction and Sanger sequencing for pathogen and host species identification. Results: In total, 256 ticks of two Ornithodorinae species were screened. Borrelia species were identified in three samples. Bloodmeal detections were made in 22 tick specimens, representing eight vertebrate host species. Conclusions: Results demonstrate that the soft tick species detected herein feed on a range of wildlife hosts in south Texas and are associated with agents of human disease.

The emergence and spread of infectious diseases, particularly zoonotic diseases originating from wildlife, pose significant threats to global health and economy. This review examines the pivotal role of ticks as vectors in transmitting pathogens to humans, livestock, and wildlife and the use of molecular techniques in their identification. Tick infestations result in economic losses through reduced animal productivity, anemia, and quality deterioration of hides. Furthermore, ticks serve as reservoirs for a wide range of pathogens including viruses, bacteria, fungi, protozoa, and nematodes, contributing to the transmission of diseases such as Crimean-Congo hemorrhagic fever, tick-borne encephalitis, and African swine fever among others. The interface between wildlife, livestock, and humans facilitates the transmission of zoonotic pathogens, exacerbated by nomadic and pastoralist lifestyles that promote interactions between wildlife and domestic animals. This movement of animals across landscapes enhances the dispersion of tick vectors, increasing the risk of pathogen exposure for diverse populations. Historically, tick identification in sub-Saharan Africa has relied on morphological characteristics despite limitations such as species overlap and variability. Molecular techniques offer a more precise means of species identification, providing critical data for effective tick and pathogen management strategies. Integrating molecular approaches into tick research enhances our understanding of tick diversity, distribution patterns, and pathogen dynamics. This knowledge is essential for developing targeted interventions to mitigate the impact of tick-borne diseases on public and veterinary health worldwide.

Introduction: Lyme disease is the most common vector-borne disease in the United States and Canada. The primary vector for the causative agent of Lyme disease, Borrelia burgdorferi, in the Pacific Northwest is the western blacklegged tick, Ixodes pacificus. Materials and Methods: Using active tick surveillance data from British Columbia, Canada, and Washington State, USA, habitat suitability models using MaxEnt (maximum entropy) were developed for I. pacificus to predict its current and mid-century geographic distributions. Passive surveillance data both from BC and WA were also visualized. Results: According to the constructed models, the number of frost-free days during the winter is the most relevant predictor of its habitat suitability, followed by summer climate moisture, ecoregion, and mean minimum fall temperature. The ensemble geographic distribution map predicts that the coastal regions and inland valleys of British Columbia and the Puget Lowlands of Washington State provide the most suitable habitats for I. pacificus. The density map of ticks submitted from passive surveillance data was overlaid on the current distribution map and demonstrates the correlation between numbers of submissions and habitat suitability. Mid-century projections, based on current climate change predictions, indicate a range expansion, especially of low and moderate suitability, from current distribution. Regarding Lyme disease risk, I. pacificus identified from both active and passive surveillance and tested positive for B. burgdorferi were found to be in areas of moderate to very high suitability for I. pacificus. Conclusion: According to developed models, the total suitable habitat area for I. pacificus will expand in the interior regions of British Columbia and Washington State. However, the risk remains small given relatively low infection rates among I. pacificus. Further studies are required to better understand how this might change in the future.

Background: Spotted fever group rickettsioses, caused by rickettsiae of the spotted fever group, pose a significant zoonotic threat to public health. In endemic areas of Anhui Province, China, the ecology and transmission dynamics of these pathogens remain under investigation. Methods: We isolated a rickettsial strain from Haemaphysalis longicornis ticks collected from a wild hedgehog in the Dabie Mountain area. Molecular identification and phylogenetic analysis were employed to confirm the strain. Pathological examinations of the hedgehog's tissues were conducted to assess the potential impact of the infection. Results: The isolated strain was identified as R. heilongjiangensis strain AH-19. Pathological examination revealed significant tissue alterations, including cellular vacuolization, necrosis, and disarray of tissue architecture. It remains uncertain whether these changes were directly attributable to the rickettsial infection or other factors. Conclusions: The identification of R. heilongjiangensis strain AH-19 in H. longicornis suggests that hedgehogs may serve as reservoir hosts in the Dabie Mountain area.Further research is needed to clarify their role in the ecology and epidemiology of this pathogen, which could inform future public health strategies.