Vector borne and zoonotic diseases最新文献

Background: Visceral leishmaniasis (VL) is a vector-borne zoonotic disease that remains endemic and poses an ongoing public health concern in western and central China. In recent years, several areas in Shaanxi Province have reported a resurgence of VL. This highlights the need for spatial risk assessments under current and future climatic conditions. Methods: This study employed the maximum entropy (MaxEnt) ecological niche modeling approach to predict the potential distribution of VL in Shaanxi Province. Historical VL case report data from 2005 to 2024 were integrated with environmental, climatic, and socioeconomic variables to identify key contributing factors and assess both current risk areas and projected future VL distributions under four Shared Socioeconomic Pathways (SSPs) across four future periods in the model. Results: The MaxEnt model showed good performance, with the area under the receiver operating characteristic curve values of 0.902 for the training data and 0.862 for the testing data. The most important contributing factors were annual mean temperature, mean temperature of the warmest quarter, and gross domestic product to VL suitability distribution. Under the current climatic conditions, the potential risk area accounted for approximately 25.28% of Shaanxi Province, with 0.97% classified as high-risk regions. These risk areas were primarily located in Hancheng, Weinan, and Shangluo City, Shaanxi Province. Under future climate scenarios, especially the high-emission pathway, high-risk regions are projected to expand significantly, particularly in northern Shaanxi. Conclusions: This study identified the influence of climatic, environmental, and socioeconomic factors on the distribution of VL in Shaanxi Province and revealed the substantial expansion of ecologically suitable areas under future climate change. The risk maps and ecological insights generated in the study can assist public health authorities in optimizing vector surveillance, region-specific surveillance, early warning, and targeted control efforts, particularly in the context of climate change.

Background: In view of Corona pandemic, scientists have taken significant efforts to study and recognize the peculiarities of the SARS-CoV-2 outbreak in order to prevent it from spreading. It was discovered that the virus is spreading in many places and nations that have made significant progress in addressing environmental pollution or are not subject to dusty storms. Infections are growing again in the same country, with varied densities of sick persons depending on the weather and windy season. Methods: Sun and dust are safe techniques for the deactivation and disinfection of SARS-CoV-2. Here, we used metal oxide discs (Fe₂O₃ 9%, SiO₂ 60%, CaO 6%, MgO 8%, and Al₂O₃ 17%) to safely disinfect SARS-CoV-2 after being subjected to the sun for 30 min. As a result, all SARS-CoV-2 were destroyed completely by transmission electron microscope (TEM) after sun exposure. Three major countries have been chosen as case studies: Italy, China, and Iran. Conclusion: It was discovered that places subjected to dust currents have a lower spread of the coronavirus. This is owing to the fact that the dust contains about 90% metal oxide, which functions as a natural photocatalyst for the synthesis of oxygen and hydrogen. These oxidizing spices can kill SARS-CoV-2.

Background: In the Netherlands, Usutu virus (USUV) is endemic in birds, and recently West Nile virus (WNV) was also detected in birds, mosquitoes and humans. Here we investigated the possible role of rodents in the viruses' transmission ecology. Materials and Methods: We sampled rodents at six locations including sites where WNV had been previously detected. Brains (n = 668), oral swabs (n = 282), and ticks (n = 91) collected from rodents were tested for arboviruses via Reverse Transcriptase Polymerase Chain Reaction (RT-PCR). Also, sera from 118 rodents were tested for WNV- and USUV-antibodies. Results and Conclusion: Brain samples, swabs, and ticks tested negative for viral RNA. However, 2.5% (3/118; two wood mice, one field vole) of rodents had WNV-neutralizing antibodies (WNV-NAbs). USUV-NAbs were detected in a wood mouse. Two bank voles had NAbs against both viruses. The WNV and USUV antibody-positive rodents were found at locations with previous WNV and USUV circulations, suggesting that rodents may be involved in the ecology of WNV and USUV.

Background and Methods: This Lyme borreliosis (LB) and Borrelia burgdorferi sensu lato (Bbsl)-infected Ixodes ticks surveillance review-from the WHO regions of the Americas, Eastern Mediterranean, Europe, South-East Asia, and Western Pacific-is informed by LB cases or incidence, Bbsl antibody seroprevalence, and Ixodes (I.) tick surveillance results from publications (2005-2022) and recent government websites. Results: LB cases, by the WHO region-country, were documented in the following: the Americas-Brazil and México; Europe-Russian Federation and Türkiye; South-East Asia-India; and Western Pacific-Japan, Mongolia, and South Korea. Mean incidence, cases/100,000 population per year (country, period), was as follows: Europe, 4.8 (Russian Federation, 2009-2021); Western Pacific, 0.01 (Japan, 2005-2021) and 0.03 (South Korea, 2012-2021). Two-tier testing Bbsl antibody seroprevalence estimate ranges were as follows: the Americas, 1.0-6.2% (Brazil), 4.6% (Colombia), and 23.1% (México); Europe, 0-15.8% (Türkiye); South-East Asia, 0.4-3.0% (India); and Western Pacific, 0-14.0% (Mongolia). Ixodes tick surveillance was presented by species (nymph, adult, or not reported, NR, life stage and [Bbsl-infected proportion]): the Americas-México, I. scapularis (NR [34.2%]); Eastern Mediterranean-Iran, I. ricinus (adult [0.9% Borrelia]); Europe-Russian Federation, I. ricinus (nymph [27.3%], nymph/adult [33.4%], adult/NR [9.8-80.4%]) and I. persulcatus (adult/NR [12.0-75.3%]) and Türkiye, I. ricinus (adult/NR [19.9%]); and Western Pacific-Japan, I. persulcatus (nymph [0-10.0%], nymph/adult [1.8-23.6%], adult/NR [detected-up to 25.5%]) and Mongolia, I. persulcatus (nymph [detected], nymph/adult [49.4%], adult [7.0-49.7%]). Conclusions: LB burden might be underrecognized in certain countries of the Americas, Eastern Mediterranean, and South-East Asia, whereas LB cases or incidence, Bbsl antibody seroprevalence, and Bbsl-infected tick presence is established in certain countries of WHO Europe (Russian Federation and Türkiye) and Western Pacific (Japan, Korea, and Mongolia), and LB could be present in neighboring countries within these WHO regions (PROSPERO: CRD42021236906).

Background: Coxiella spp. are widespread in ticks. Coxiella burnetii, the agents of Q fever, is vectored by ticks and is well known for its veterinary and medical importance. However, reports on C. burnetii in ticks from China have been quite few compared with other tick-borne pathogens. In addition to C. burnetii, more and more Coxiella endosymbionts of ticks have been described in China. Materials, Methods, and Results: In this study, ticks were collected from domestic animals in two provinces (Chongqing and Xinjiang) in western China, and the Coxiella spp. in them were molecularly studied. In the 168 ticks (all Hyalomma asiaticum) from Xinjiang, C. burnetii was detected with an overall positive rate of 76.19%. In contrast, in 96 ticks (all Rhipicephalus microplus) from Chongqing, only Coxiella endosymbiont was identified with an extremely high prevalence (97.92%). Conclusions: We propose that there may have been a tick-animal-tick circulation of C. burnetii in Xinjiang. The high positive rate of C. burnetii suggests a high risk to public health.

Background: The zoonotic infectious disease, severe fever with thrombocytopenia syndrome (SFTS), caused by the SFTS virus (SFTSV), Bandavirus dabieense, was first identified in China in 2009 and reported in the Republic of Korea in 2013. The primary vector is the tick Haemaphysalis (H.) longicornis, which is endemic to the Asia-Pacific region and has a wide range of hosts. While SFTSV has been studied in various wildlife species, no investigation has focused explicitly on bats, which are ecologically significant in the transmission of zoonotic viruses. Materials and Methods: To investigate the relationship between bats and SFTSV, 1,200 ticks were collected from 12 sites in 6 provinces within 1 km of bat habitats using flagging, and 147 bat sera were collected via cardiac puncture after ether anesthesia between November 2021 and September 2022. Total RNA was extracted from the ticks and bat sera, and nested reverse transcription polymerase chain reaction was performed to amplify the S segment of SFTSV. Bat sera were analyzed for IgG antibodies against SFTSV by enzyme-linked immunosorbent assay (ELISA). Results: Within 1 km of bat habitats, 881 H. longicornis, 209 H. flava, 96 Haemaphysalis spp., and 14 Ixodes (I.) nipponensis were identified. SFTSV was detected in 12.3% (147/1,200) of the ticks. Although no SFTSV RNA was detected in bat sera by nested PCR, 3.4% (5/147) were seropositive by ELISA. Conclusion: While molecular evidence of SFTSV infection was not observed in bats, a few serological positives suggest possible past exposure. The detection of SFTSV in ticks collected from bat habitats suggests potential ecological interactions involving bats, ticks, and other wildlife species. These findings highlight the importance of considering both wildlife reservoirs and the indirect role of bats in the geographical spread of SFTSV.

Background: Mosquitoes harbor diverse insect-specific viruses (ISVs) frequently overlooked in arbovirus surveillance. Comprehensive characterization of ISVs is crucial for understanding their impact on host ecology and potential roles in arbovirus transmission. Methods: Using metagenomic sequencing on Armigeres subalbatus from Yunnan, China, we identified two novel picorna-like viruses, assembled their genomes, and conducted phylogenetic analysis. Detection was confirmed via RT-PCR and Sanger sequencing. Results: Both viruses are closely related to Hubei picorna-like virus 59, previously reported in spiders but unconfirmed. This work provides the first genomic evidence of this lineage in mosquitoes. Conclusion: This study characterizes two novel ISVs, expanding known picorna-like virus diversity and offering insights into cross-species virus evolution and arbovirus ecology.

Background: Arboviruses, transmitted to humans and animals by blood-feeding arthropods, pose significant public health risks. This study investigates the types, distribution, and epidemiology of arboviruses in the central Yuxi region of Yunnan Province, providing crucial data for the prevention and control of mosquito-borne diseases. Methods: In 2015, mosquitoes were collected from Tonghai County, Huaning County, Jiangchuan District, and Chengjiang County in Yuxi using light traps. The mosquitoes were homogenized, and virus isolation was performed by inoculating the homogenates onto BHK-21 (baby hamster kidney) and C6/36 (Aedes albopictus) cell lines. Reverse Transcription Polymerase Chain Reaction (RT-PCR) amplification was performed with universal and virus-specific primers, followed by sequencing of positive products using bioinformatics tools (DNAstar, MEGA X). Results: A total of 13,050 mosquitoes from four counties were collected, with 261 pools processed for virus detection. The mosquitoes belonged to three genera: Culex Anopheles and Aedes, with Culex tritaeniorhynchus as the predominant species. Cytopathic effects were observed in 95 pools. Nine viruses were identified: Japanese Encephalitis Virus (JEV), Bannavirus, Getah Virus, Tibet Orbivirus (TIBOV), Nam Dinh Virus, Akabane Virus (AKAV), Ngewotan Virus (NWTV), Quang Binh Virus (QBV), and Culex pipiens pallens densovirus. The distribution of viruses varied: six viruses with 35 isolates in Tonghai County; six viruses with 88 isolates in Huaning County; two viruses with five isolates in Chengjiang County; and no viruses were found in Jiangchuan District. TIBOV and NWTV were present in all three counties, while JEV, AKAV, and QBV were found only in Tonghai County. Conclusion: Nine arboviruses were isolated across four counties in Yuxi, with varying distributions. This highlights the epidemiological diversity of mosquito-borne viruses in the region, emphasizing the need for targeted control measures.

Introduction: Herbs and their products are a source for drug discovery, and most of all synthetic drugs originate from them. The present study was designed to evaluate the in vitro and in vivo efficacy, as well as the potential mechanisms, of Rhanterium epapposum essential oil (REE), β-myrcene (MC), camphene (CP), and limonene (LN) alone and in combination with pyrimethamine (PYM) against Toxoplasma gondii. Materials and Methods: In vitro, the effectiveness of REE and its components on tachyzoites, the infectivity rate, caspase-3 activity, and nitric oxide (NO) and expression levels of inducible NO synthase and gamma interferon (IFN-γ) genes were evaluated. In the in vivo assays, infected mice received REE, MC, CP, and LN either alone or in combination with PYM for 2 weeks. Subsequently, the number and diameter of tissue cysts, oxidant/antioxidant enzyme levels, inflammatory cytokines, and bradyzoite surface antigen 1 (BAG1) gene expression were examined. Results: The best 50% inhibitory concentration values were reported for MC + LN, PYM + MC, and MC + CP, with values of 12.1, 15.4, and 16.6 µg/mL, respectively. REE and its primary compounds significantly increased (p < 0.001) NO release (6.6-14.1 nM), caspase-3 activity, and the expression levels of inducible NO synthase and IFN-γ genes in cells. In addition, significantly decreased (p < 0.001) the number (0.0-115.3 cysts) and size (0.0-83.1 nm) of tissue cysts, oxidative stress markers, decreased the expression levels of IL-1β and TNF-α, and BAG1 (0.48-5.10 fold change), while, significantly increased (p < 0.001) glutathione peroxidase (1.65-5.12 U/mg) and superoxide dismutase (31.9-74.1 U/mg) levels in the infected mice. Conclusions: We demonstrated the high in vitro and in vivo efficacy of REE and its principal compounds against chronic toxoplasmosis. The highest efficacy was observed following combination therapy of T. gondii-infected mice with PYM and these compounds, with a significant difference noted compared with PYM alone. However, further trials must validate these findings and clarify the underlying mechanisms.

Background: The COVID-19 pandemic, driven by the SARS-CoV-2 virus, has become an unprecedented global public health challenge. Comprehensive investigation of the virus transmission dynamics requires exploration of all potential routes, including the role of animal reservoirs. This study aimed to assess the presence of SARS-CoV-2 RNA and antibodies in urban rodents captured within two landscape units (low-income neighborhoods and green spaces) in the metropolitan area of Buenos Aires (MABA), Argentina. Methods: Between July 2020 and September 2022, 125 synanthropic rodents (68 Rattus norvegicus, 22 R. rattus, and 35 Mus musculus) from seven low-income neighborhoods and seven green spaces in the MABA were captured and examined for SARS-CoV-2 exposure and infection by indirect immunofluorescence serology and RT-qPCR, targeting the N, E, and ORF1ab genes. Results: Two M. musculus and six R. norvegicus from five different low-income neighborhoods tested positive for SARS-CoV-2 antibodies. No rodent with positive serology was detected in green spaces. All rodents tested negative for SARS-CoV-2 RNA when analyzed by RT-qPCR. Conclusion: The results of this study provide valuable insights into the ecological dynamics of SARS-CoV-2 in synanthropic rodents in two landscape units within a Latin American city, with seropositive rodents detected in low-income neighborhoods, suggesting a possible increased exposure risk in these settings. This information is critical for developing management strategies for potentially zoonotic viruses and underscores the importance of continued surveillance of SARS-CoV-2 in rodents as part of an integrated One Health approach.