Vector borne and zoonotic diseases最新文献

Introduction: COVID-19 is an infectious disease caused by SARS-CoV-2 that has become a serious threat to public health owing to its rapid spread from aerosols from infected people. Despite being considered a strictly human disease, there are reports in the literature about animals with confirmed presence of the virus. Aim: Owing to the scarcity of scientific literature on the potential for infection of animals and their importance for One Health, the objective of this work was to research SARS-CoV-2 RNA in felines (Felis silvestris catus) and dogs (Canis lupus familiaris) domiciled. Materials and Methods: Oropharyngeal swabs were collected from domestic dogs and cats belonging to patients diagnosed with COVID-19 from August to October 2021 and residents of the northwest and west regions of Paraná, Brazil. Results: Of the 34 samples collected, 14 were from dogs and 20 from cats. Three of these samples tested positive in real-time PCR, and two of them were also positive in the immunochromatographic test. After testing positive in real-time PCR, the samples underwent genetic sequencing using the Illumina COVIDSeq test. Of the 34 samples collected, three (9%), all of them female and from the feline species, tested positive in real-time PCR, with two of these (67%) also testing positive in the immunochromatographic test. Regarding sequencing, it was possible to sequence the three samples aligned with the AY.101 lineage, corresponding to the Delta variant. Conclusion: The occurrence of SARS-CoV-2 infection in dogs and cats is seen as an unintended event with significant implications for public health, including its potential transmission to other animal species. Further research is required to enhance our understanding of how this disease spreads among these animals and its broader impact on One Health initiatives.

Background: This study conducted in the departments of Oueme and Plateau aims to assess the presence of the dengue virus and its different serotypes in Aedes aegypti and Aedes albopictus, as well as the epidemic risk incurred by the populations. Methods: Collections of adult mosquitoes using human landing catches (HLC) were carried out in six communes, three (Porto-Novo, Adjarra, and Avrankou) in the Oueme department and the rest (Ifangni, Kétou, and Pobè) in the Plateau department. Pools of ten Aedes mosquitoes were formed, and stored at -80°C in RNA later. RT-PCR was used to detect dengue virus, and conventional PCR for the different serotypes. Inspection of water containers and collection of Aedes larvae was performed inside and around each house to calculate the stegomyan indices. Results: In the six communes, the dengue virus was present both in Ae. aegypti and Ae. albopictus. Combined data of the two Aedes species at the communes level revealed infection rates ranging from 80.00% (95% CI: 61.43-92.29) to 96.67% (95% CI: 82.78-99.92). In all the communes, the values of stegomyan indices reached the WHO threshold, which indicates the existence of the risk of an arbovirus epidemic. In addition, the infection rates were similar for Ae. aegypti [88.19% (95% CI: 81.27-93.24)] and Ae. albopictus [86.79% (95% CI: 74.66-94.52)]. The three virus serotypes detected in the pools of Aedes were DENV-1, DENV-3, and DENV-4, with a high prevalence for the first two. Conclusion: This study revealed that three serotypes (DENV-1, DENV-3, and DENV-4) of dengue virus circulate in Ae. aegypti and Ae. albopictus in the departments of Oueme and Plateau. Moreover, the risk of transmission of arboviruses was globally high and variable from commune to commune. This information is essential for informed decision-making in the preventive control of the disease.

Data mining and artificial intelligence algorithms can estimate the probability of future occurrences with defined precision. Yet, the prediction of infectious disease outbreaks remains a complex and difficult task. This is demonstrated by the limited accuracy and sensitivity of current models in predicting the emergence of previously unknown pathogens such as Zika, Chikungunya, and SARS-CoV-2, and the resurgence of Mpox, along with their impacts on global health, trade, and security. Comprehensive analysis of infectious disease risk profiles, vulnerabilities, and mitigation capacities, along with their spatiotemporal dynamics at the international level, is essential for preventing their transnational propagation. However, annual indexes about the impact of infectious diseases provide a low level of granularity to allow stakeholders to craft better mitigation strategies. A quantitative risk assessment by analytical platforms requires billions of near real-time data points from heterogeneous sources, integrating and analyzing univariable or multivariable data with different levels of complexity and latency that, in most cases, overwhelm human cognitive capabilities. Autonomous biosurveillance can open the possibility for near real-time, risk- and evidence-based policymaking and operational decision support.

Background: Toxoplasmosis is caused by infection with Toxoplasma gondii. No Symptoms in healthy people. Notably, very dangerous symptoms in immunocompromised, or patients with immune diseases. Previous research has shown that the parasite's resistance to drugs continues to emerge and has indicated this resistance as a cause for concern. In this context, researchers have a great responsibility to search for alternative treatments, as well as to develop existing ones. Essentially, this improves the therapeutic efficacy of drugs and prevents the emergence of resistance to them. The present study aims to evaluate antitoxoplasma effects of niosomal loaded curcumin and silymarin and their synergistic effects with clindamycin against T. gondii RH strain in vitro. Materials and Methods: Experiments were conducted on the tachyzoites of T. gondii RH-strain, based on: the free and nieosomal compounds of curcumin and silymarin, in addition to the drug clindamycin. Data were collected to estimate parasite viability during exposure to the therapeutic compounds under study using a special MTT assay ((3-(4, 5-dimethylthiazolyl-2)-2,5-diphenyltetrazolioum bromide) assay: is a colorimetric assay for measuring cellular growth) kit provided by (Bio Idea Company, Tehran, Iran). Hence, the effect of the therapeutic compounds on the parasite load was studied using the quantitative molecular technique real-time PCR. Results: The results indicate that the combination of N-silymarin and N-curcumin with clindamycin has active synergistic effects against T. gondii leading to complete elimination of the parasite. Data revealed that curcumin and silymarin in both their free and nisomal forms had inhibitory effects on the parasite, and minimal toxic effects on normal cells. Conclusions: The results highlight the successful synergistic effect of clindamycin and the niosomal compounds curcumin and silymarin in completely eradicating the T. gondii RH-strain. This finding contributes positively to the field of safe and effective treatments.

Background and Objectives: Malaria airs a life-threatening risk in Tropical African countries, stemming from infection by Plasmodium species. This region is richly endowed by nature with a wealth of diverse and largely unexplored plants that hold the potential for managing this protozoan parasite. The currently accessible over-the-counter drugs for disease management often present affordability challenges for the average person, exacerbated by the parasite's increasing resistance to them. This study investigated the phytoconstituents present in the ethyl acetate fraction of Spilanthes filicaulis (EFSF) and explored the antimalarial effects of EFSF on mice infected with Plasmodium berghei. Methods: Standard methods and gas chromatography-mass spectrometry (GC-MS) were used to identify phytoconstituents. Chloroquine phosphate-sensitive P. berghei (NK-65) was intraperitoneally inoculated into Swiss mice. The in vivo antimalarial activity of EFSF was assessed at dose levels of 250, 500, and 750 mg/kg, using 4-day suppressive and curative antimalarial models. Parameters evaluated in the inoculated mice included rectal temperature (RT), body weight (BW), packed cell volume (PCV), level of parasitemia, and mean survival time (MST). Results: Steroids, alkaloids, flavonoids, tannins, saponins, terpenoids, and cardiac glycosides were the identified phytochemicals present in EFSF, and GC-MS alongside reveals the presence of 20 bioactive compounds predominantly fatty acids and alcohol esters. Significant prevention of reductions in RT, BW, and PCV was observed in the EFSF-treated groups dose dependently relative to the untreated group. In addition, EFSF-treated groups significantly (p < 0.05) suppressed parasitemia and exhibited chemosuppression of 79.46% and 77.38% in 4-day suppressive, whereas suppression of 59.74% and 58.66% in curative treatment, respectively, at 500 and 750 mg/kg thus consequently extending the MST of infected treated mice compared with the untreated group. Interpretation and Conclusion: Put together, the EFSF exhibited enhanced antimalarial efficacy against mice infected with P. berghei thus affirming that plants still maintain lead way as a potential source of novel antimalarial remedies.

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.

Background: Dengue is a mosquito-borne tropical disease, caused by the Dengue virus (DENV). It has become a severe problem and is a rising threat to public health. In this study, we have evaluated commercial Merilisa i Dengue NS1 Antigen kit (Meril LifeSciences India Pvt. Ltd.) to detect recombinant dengue virus 2 NS1 antigen (rDNS1Ag) and secreted forms of NS1 antigen (sDNS1Ag). Methods: To determine the detection limit of the kit, 100 nanogram (ng) to 0.001 ng rDNS1Ag was tested. The sensitivity and specificity of the kit was determined using recombinant NS1 antigens of all serotypes of DENV and other flaviviruses. For testing sDNS1Ag, the culture supernatant of the Vero cell lines infected with DENV-2 was tested. Further, a spiking experiment was carried out to check the sensitivity of the kit to detect rDNS1Ag in the pools of Aedes aegypti mosquitoes. Results: It was observed that the kit can detect the rDNS1Ag at 1 ng concentration. The kit was sensitive to detect NS1 antigen of DENV-1, DENV-2 and DENV-3 serotypes and specific for detection of only DNS1Ag as it did not cross-react with NS1 antigen of flaviviruses. The kit was sensitive to detect rDNS1Ag in the mosquito pools as well. In addition, the kit was able to detect the sDNS1Ag in Vero cell culture supernatant. Conclusions: Overall, we observed that the Merilisa i Dengue NS1 Ag kit is sensitive and specific for the detection of DNS1Ag both in recombinant and secretory forms.

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.

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: Kadipiro virus (KDV) is a species of the new 12 segmented RNA virus grouped under the genus Seadornavirus within the Reoviridae family. It has previously been isolated or detected from mosquito, Odonata, and bat feces in Indonesia, China, and Denmark, respectively. Here, we describe the isolation and characterization of a viral strain from mosquitoes in Yunnan Province, China. Methods: Mosquitoes were collected overnight using light traps in Shizong county, on July 17, 2023. Virus was isolated from the mosquito homogenate and grown using baby hamster kidney and Aedes albopictus (C6/36) cells. Preliminary identification of the virus was performed by agarose gel electrophoresis (AGE). The full-genome sequences of the strain were determined by full-length amplification of cDNAs and sequenced using next-generation sequencing. Results: We isolated a viral strain (SZ_M48) from mosquitoes (Culex tritaeniorhynchus Giles) that caused cytopathogenic effects in C6/36 cells. AGE analysis indicated a genome consisting of 12 segments of double-stranded RNA that demonstrated a "6-5-1" pattern, similar to the migrating bands of KDV. Phylogenetic analysis based on the full-genome sequence revealed that SZ_M48 is more clustered with KDV isolates from Hubei and Shangdong in China than with Indonesian and Danish strains. The identity between SZ_M48 and SDKL1625 (Shandong, China) is slightly lower than that of QTM27331 (Hubei, China), and the identity with JKT-7075 (Indonesia) and 21164-6/M.dau/DK (Denmark) is the lowest. Conclusion: The full-genome sequence of the new KDV strain described in this study may be useful for surveillance of the evolutionary characteristics of KDVs. Moreover, these findings extend the knowledge about the genomic diversity, potential vectors, and the distribution of KDVs in China.