Infection Levels Research Articles

Impact of ivermectin and vector control on onchocerciasis transmission in Togo: Assessing the empirical evidence on trends in infection and entomological indicators.

The World Health Organization's 2021-2030 Road Map for Neglected Tropical Diseases boosted global commitment towards the elimination of onchocerciasis, but the timeline to elimination will vary strongly between countries in Africa. To assess progress towards elimination in the Republic of Togo, we reviewed the history of control and time trends in infection. We collated all available programmatic, entomological, and epidemiological data since the initiation of the Onchocerciasis Control Programme (OCP) in Togo through different data sources. We then visualised data trends over time, to assess the impact of interventions on infection and transmission levels. Vector control was initiated by OCP from 1977 (northern and central parts of Togo) or 1988 (southern regions) up to 2002 (most areas) or 2007 ("special intervention zones" [SIZ], parts of Northern and Central Togo). Between 1988 and 1991, Togo initiated ivermectin mass drug administration (MDA) in eligible communities. The impact of vector control was high in most river basins, resulting in low annual biting rates and annual transmission potential declining to very low levels; the impact was lower in river basins designated as SIZ. Repeated, longitudinal ivermectin mass treatments have overall strongly reduced onchocerciasis transmission in Togo. Epidemiological surveys performed between 2014 and 2017 showed that the prevalence of skin microfilariae (mf) and anti-OV16 IgG4 antibodies had declined to low levels in several districts of the Centrale, Plateaux, and Maritime region. Yet, relatively high mf prevalences (between 5.0% and 32.7%) were still found in other districts during the same period, particularly along the Kéran, Mô and Ôti river basins (SIZ areas). Trends in infection prevalence and intensity show that onchocerciasis levels have dropped greatly over time in most areas. This demonstrates the large impact of long-term and wide-scale interventions, and suggest that several districts of Togo are approaching elimination.

Infection-nutrition feedbacks: fat supports pathogen clearance but pathogens reduce fat in a wild mammal.

Though far less obvious than direct effects (clinical disease or mortality), the indirect influences of pathogens are difficult to estimate but may hold fitness consequences. Here, we disentangle the directional relationships between infection and energetic reserves, evaluating the hypotheses that energetic reserves influence infection status of the host and that infection elicits costs to energetic reserves. Using repeated measures of fat reserves and infection status in individual bighorn sheep (Ovis canadensis) in the Greater Yellowstone Ecosystem, we documented that fat influenced ability to clear pathogens (Mycoplasma ovipneumoniae) and infection with respiratory pathogens was costly to fat reserves. Costs of infection approached, and in some instances exceeded, costs of rearing offspring to independence in terms of reductions to fat reserves. Fat influenced probability of clearing pathogens, pregnancy and over-winter survival; from an energetic perspective, an animal could survive for up to 23 days on the amount of fat that was lost to high levels of infection. Cost of pathogens may amplify trade-offs between reproduction and survival. In the absence of an active outbreak, the influence of resident pathogens often is overlooked. Nevertheless, the energetic burden of pathogens likely has consequences for fitness and population dynamics, especially when food resources are insufficient.

Highly sensitive wastewater surveillance of SARS-CoV-2 variants by targeted next-generation amplicon sequencing provides early warning of incursion in Victoria, Australia.

The future of the COVID pandemic and its public health and societal impact will be determined by the profile and spread of emerging variants and the timely identification and response to them. Wastewater surveillance of SARS-CoV-2 has been widely adopted in many countries across the globe and has played an important role in tracking infection levels and providing useful epidemiological information that cannot be adequately captured by clinical testing alone. However, novel variants can emerge rapidly, spread globally, and markedly alter the trajectory of the pandemic, as exemplified by the Delta and Omicron variants. Most mutations linked to the emergence of new SARS-CoV-2 variants are found within variable regions of the SARS-CoV-2 Spike protein. We have developed a duplex hemi-nested PCR method that, coupled with short amplicon sequencing, allows simultaneous typing of two of the most highly variable and informative regions of the Spike gene: the N-terminal domain and the receptor binding motif. Using this method in an operationalized public health program, we identified the first known incursion of Omicron BA.1 into Victoria, Australia and demonstrated how sensitive amplicon sequencing methods can be combined with wastewater surveillance as a relatively low-cost solution for early warning of variant incursion and spread.IMPORTANCEThis study offers a rapid, cost-effective, and sensitive approach for monitoring SARS-CoV-2 variants in wastewater. The method's flexibility permits timely modifications, enabling the integration of emerging variants and adaptations to evolving SARS-CoV-2 genetics. Of particular significance for low- and middle-income regions with limited surveillance capabilities, this technique can potentially be utilized to study a range of pathogens or viruses that possess diverse genetic sequences, similar to influenza.

Development of parasite complexes in the ecosystem of the rose garden of the main Botanical Garden of the Russian Academy of Sciences

The article reports on studies (2011-2022) monitoring harmful organisms in the ecosystem of the rose garden of the Main Botanical Garden of the Russian Academy of Sciences. The studies yielded data on the detection of pathogens and pests, as well as the phenotypic manifestation of pathologies and lesions. A total of 21 species of pathogens and 16 species of phytophages were identified. The species composition of harmful organisms in the ecosystem of the rose garden was defined. It is shown that at the initial stage (2011- 2013) of ecosystem establishment, no external signs of viral diseases were observed, and a low level of fungal infections was noted. The development of such harmful pathogens as Peronospora sparsa Jacz., Sphaerotheca pannosa Lev., Phragmidium disciflorum James, and Ph. tuberculatum Mull. was controlled by culling plants of susceptible varieties. The predominant pathogens included Marssonina rosae (Lib.) Died., Phyllosticta rosae Desm., and Septoria rosae Desm., and the susceptibility of specific varieties to these pathogens was established. The populations of pathogens causing spot anthracnose (Sphaceloma rosarum Pass.), ascochyta leaf spot (Ascochyta rosicola Sacc.), and cercospora leaf spot (Cercospora rosicola Pass.) were slightly less common. A wide range of signs of viral infections was identified. Nine viruses belonging to five genera were detected. The frequency of their occurrence was analyzed, and the most common viruses were identified: Prunus necrotic ring spot ilarvirus, Apple mosaic ilarvirus, Tobacco ring spot nepovirus, and Arabis mosaic nepovirus. The species diversity of phytophages was noted: leaf beetles, snout beetles, leafroller moths, sawflies, blossom weevils, earwigs, moths, leafhoppers, aphids, and true bugs. It was found that damage to plants by a range of pests reached only an average level, except for individual varieties (Red Blanket and Prosperity). In general, the phytosanitary assessment of the rose gene pool of the garden according to the phytosanitary monitoring and integrated detection revealed a wide range of parasite complexes: fourteen types of pathogenic complexes, four types of entomological complexes, and five types of entomopathogenic complexes. The tactical and basic directions for control of harmful organisms in the ecosystem of the rose garden are discussed.

ВЕТЕРИНАРНО-САНИТАРНАЯ ЭКСПЕРТИЗА ПРОДУКТОВ УБОЯ В СТРУКТУРЕ ПАРАЗИТАРНЫХ ЗАБОЛЕВАНИЙ В КАБАРДИНО-БАЛКАРСКОЙ РЕСПУБЛИКЕ

The purpose of research is to study the results of post-mortem examination of beef, to monitor parasitic diseases among the population of the Kabardino-Balkarian Republic. The material for the study was the data obtained from post-mortem examinations from 2020 to 2022 and information from the Center for Hygiene and Epidemiology of the Office of the Federal Service for Surveillance on Consumer Rights Protection and Human Welfare in the Kabardino-Balkarian Republic for the same period. Recently, a significant part of productive animals in the territory of the Kabardino-Balkarian Republic comes from the southern regions of the Russian Federation. Based on the results of reports conducted by the veterinary service for the period 2020–2022. 7,427 cattle carcasses were identified with affected organs and tissues by the following invasive diseases: Fasciolosis, Echinococcosis, Dicrocoeliasis. In 2020, the highest infection rate was due to Echinococcus granulosus infestation – 42.54 %, followed by Fasciola hepatica and Fasciola gigantica – 32.52 %; the smallest – when infected with Dicrocoelium lanceatum – 24.94 %. In 2021, the highest level of infection was also due to infection by Echinococcus granulosus – 39.02 %, then Fasciola hepatica and Fasciola gigantica – 36.72 %, the lowest was due to infection by Dicrocoelium lanceatum – 24.24 %. In 2022, most of the culling occurred due to infestation: Echinococcus granulosus – 38.50 %, then Fasciola hepatica and Fasciola gigantica – 36.80 %, the least due to infection with Dicrocoelium lanceatum – 24.68 %. Favorable natural and climatic conditions, pasture animal husbandry, and peculiarities of the social structure of the population of the Kabardino-Balkarian Republic lead to the interaction of the pathogen and host populations. Based on the results of epidemiological examinations of foci of invasive diseases of the population in the Russian Federation, the following results were obtained: over the past 5 years (2017–2021), 1,909 cases of infection with Echinococcus granulosus were identified. In total, 551 cases of infection with Echinococcus granulosus and Echinococcus multilocularis were registered in the Russian Federation in 2022.

Using Stable Isotope Techniques to Analyze the Trophic Relationship between Argentine Hake (Merluccius hubbsi) and Anisakidae.

The Argentine hake (Merluccius hubbsi) is a vital fishery species in the Southwest Atlantic, recognized for its substantial economic importance. Previous studies have identified Anisakidae larvae as common parasites of M. hubbsi. However, the nutritional relationships between these parasites and their host remain poorly understood. This study employs stable isotope techniques to investigate the specific nutritional relationships between Anisakidae larvae and different tissues of M. hubbsi. The findings reveal notable differences in δ13C and δ15N compositions between the parasites and their host. The lower δ13C values in parasites compared to host tissues indicate the utilization of different carbon sources. The δ15N values of the parasites partially overlap with those of the host's stomach, indicating that the parasites primarily derive nutrients from the host's stomach. Nutritional niche indicators show that parasites have a broad carbon range (CR) and nitrogen range (NR), suggesting a high diversity in nutritional sources. The trophic discrimination factor (ΔTDF), which represents the difference in stable isotope values between host tissues and parasites, was analyzed for both δ13C and δ15N. The ΔTDFδ13C between the host liver and the parasites showed the greatest variation, indicating a strong dependence of the parasites on the liver's carbon sources. In contrast, variations in ΔTDFδ15N between host tissues and parasites were minimal. Analyzing ΔTDF across different stages of gonadal maturity in the host fish indicates that, as the gonads of the host fish mature, ΔTDFδ13C between host tissues and parasites significantly decreases (p < 0.01). The Kruskal-Wallis test showed significant differences in ΔTDFδ13C values among different parasite infection levels in muscle, liver, and stomach tissues, while no significant differences were found for ΔTDFδ15N values. These findings offer valuable insights into the nutritional relationships between parasites and hosts, aiding in a better understanding of the growth conditions and habitats of M. hubbsi.

Investigating the Prevalence of the Giardia lamblia Parasite in Children in Salah Al-Din Governorate

The research was conducted from June 2023 until December 2024 to detect the prevalence of infection with the Giardia lamblia parasite among children with diarrhea attending Tikrit Teaching Hospital in Salah al-Din Governorate. The study included collecting 400 stool samples for children whose ages ranged between (1-12) years. Direct wet swab to detect the presence of the parasite. The level of infection with the parasite reached 14.75%. The highest rate of infection was in males at 67.7% and lower in females at a rate of 32.2%. The highest rate of infection was at the age of (1-3) years at a rate of 38.9% and the lowest rate was 11.8% at the age of (9-12) years. The infection rate was 69.4%, high in families with 10 or more members, while in small families (4-5) individuals, the infection rate was 30.5%. The infection rate was highest in children who drank unfiltered river water, at 50.8%, and lowest in children who drank pure water, at 3.3%. The prevalence of this parasite in rural areas was higher than in urban areas, at a rate of 55.9% in all areas of the governorate. It was found that there were varying rates of infection in the different months of the year, reaching 28.8% in the summer, and the lowest infection rate in the winter.

NF-κB inhibitor alpha controls SARS-CoV-2 infection in ACE2-overexpressing human airway organoids

As SARS-CoV-2 continues to spread worldwide, tractable primary airway cell models that recapitulate the cell-intrinsic response to arising viral variants are needed. Here we describe an adult stem cell-derived human airway organoid model overexpressing the ACE2 receptor (ACE2-OE) that supports robust viral replication while maintaining 3D architecture and cellular diversity of the airway epithelium. ACE2-OE organoids were infected with SARS-CoV-2 variants and subjected to single-cell RNA-sequencing. Interferon-lambda was upregulated in cells with low-level infection while the NF-kB inhibitor alpha gene (encoding IkBa) was consistently upregulated in infected cells, and its expression positively correlated with infection levels. Confocal microscopy showed more IkBa expression in infected than bystander cells, but found concurrent nuclear translocation of NF-kB that IkBa usually prevents. Overexpressing a nondegradable IkBa mutant reduced NF-kB translocation and increased viral infection. These data demonstrate the functionality of ACE2-OE organoids in SARS-CoV-2 research and underscore that the strength of the NF-kB feedback loop in infected cells controls viral replication.

Temporal dynamics of parasite populations and communities of blue sea catfish Ariopsis guatemalensis (Günther, 1864), in a eutrophic coastal lagoon from Mexican Pacific

ABSTRACT The temporal dynamics of parasite populations and communities of blue sea catfish Ariopsis guatemalensis from a tropical eutrophic coastal lagoon was studied during an annual cycle. A total of 620 adult fishes were collected between January and December 2019. Eleven taxa of parasites were identified, three of monoxenous (single-host life cycle), and eight of heteroxenous (multi-host life cycle) parasites. The infection levels of two monoxenous (Neotetraonchus vegrandis and Ergasilus sp.) and five heteroxenous (Austrodiplostomum sp. Pseudoacanthostomum panamense, Pseudoleptorhynchoides lamothei, Contracaecum sp. and Hysterothylacium perezi) parasite species varied between sampling months and/or climatic seasons. The infection dynamics of these group of parasites were influenced by environmental changes generated by the dry/rainy cycle, which can affect the availability of intermediate host populations, and the feeding and reproductive behaviour of the host. Although the species composition of the parasite communities remains quite stable over time, its structure registers important changes mainly during the rainy season. Some host traits such as the feeding and reproductive behaviour, body size, physical condition, and sex of the host, as well as the temporal replacement of numerically dominant parasite species, were the main factors responsible for variations in the parasite community structure.

Prevalence of the crayfish plague pathogen in red swamp crayfish populations in western France: How serious is the risk for the native white-clawed crayfish?

The crayfish plague pathogen Aphanomyces astaci has been implicated in a number of mass mortalities and irreversible population declines of native crayfish across Europe. At present, the reservoirs of the pathogen in Europe are mainly populations of invasive North American crayfish species. In southwestern Europe, including France, a particularly widespread invader is the red swamp crayfish Procambarus clarkii. Recent distribution data confirm that P. clarkii is present in at least 75 French departments, i.e. more than 78% of those in metropolitan France. We analysed the prevalence and pathogen load of A. astaci in 42 populations of this species in western France (Nouvelle Aquitaine region), where the species is most densely distributed, particularly in a wide range of environments around the Gironde estuary. The pathogen was detected by two different quantitative PCR assays in more than three quarters of the populations studied (34 out of 42); 163 out of 480 analysed crayfish individuals tested positive for the presence of A. astaci. In most cases, individual infection levels were very low, detectable with quantitative PCR but not sufficient for pathogen genotyping. In seven P. clarkii individuals from four populations, however, we were able to assess A. astaci variation by microsatellite markers and sequencing of mitochondrial markers. All these host specimens carried A. astaci genotype group D, haplotype d1, which has caused the majority of crayfish plague outbreaks in neighbouring Spain. In contrast, the French outbreaks genotyped to date (including eight newly analysed in this study) were mostly caused by strains of genotype group B, specific to the signal crayfish Pacifastacus leniusculus. Haplotype d1 found in P. clarkii was involved in one of the newly characterised outbreaks. Our study confirms that P. clarkii is a potentially important reservoir of the crayfish plague pathogen in France, but not the main source of the pathogen in mass mortalities of A. pallipes, probably due to different ecological requirements of the different invasive host crayfish. However, as P. clarkii continues to spread, the threat posed by this species to native crayfish is likely to increase.

Comparison the results of surgical treatment of metastatic lesions of the thoracic spine (systematic review)

Objective: to conduct a comparative analysis of the effectiveness of surgical treatment for patients with metastatic lesions of the thoracic spine from anterior and posterior approaches according to the literature. Methodology for writing a review. The search was carried out in the PubMed and Scopus databases. Search words and phrases: "thoracic spine", "metastatic lesion", "spinal cord", "management of thoracic spine metastasis". Search depth for the last 15 years. 13 publications were included in the final analysis. Conclusion. Both approaches are effective, but data such as blood loss, duration of surgery, neurological changes and pain intensity are significantly better in patients who underwent anterior approach. At the same time, in this group the development of respiratory failure is more common, and the 30-day mortality rate is higher compared to group of posterior approach. In the group of posterior interventions there was a significantly higher level of postoperative CSF leakage and wound infection, as well as worsening neurological deteriorations. The frequency of failure of implanted structures and revision interventions for wound hematomas and recurrent tumor growth is almost the same.

Элементы технологии применения лабораторных образцов смесевых микробиологических препара-тов в препаративной форме смачивающийся порошок на основе перспективных штаммов антагонистов на фоне естественного поражения масличного льна фузариозом в полевых условиях

In 2022, laboratory samples of mixed microbiological preparations in a preparative form wettable powder (WB) based on promising strains-producers were tested in the laboratory of biological methods at the V.S. Pustovoit All-Russian Research Institute of Oil Crops in field conditions under natural infection of oil flax with fusariosis. We determined the optimal consumption rates the laboratory samples of WB of the mixed microbiopreparations based on different ratios (1 : 1; 1 : 2; 1 : 3) of promising fungal T-1 Trichoderma sp. and bacterial 11-3 Bacillus sp. components. A chemical etalon Redigo Pro had no protective effect at a middle level of fusariosis infection (25.9%) on oil flax variety VNIIMK 620 in control variant without microbiopreparations treatment. The biological etalons based on a separate producer had the biological efficiency against disease for a fungal strain with a consumption rate of 0.05 kg/t – 66.0% with a low additional yield of 0.17 t/ha, and for a bacterial strain with a consumption rate of 0.2 kg/t – 40.5% with additional yield 0.24 t/ha. The optimal consumption rate of the laboratory samples WP of the mixed microbiopreparations in all test variants of ratios be-tween fungal and bacterial components id 0.3 kg/t. At this consumption rate of wettable powder, ratio 1 : 1 had the biological efficiency against fusariosis 54.8% with an additional yield of 0.44 t/ha; ratio 1 : 2 had a protective effect of 40.5% and additional yield of 0.23 t/ha; the biological efficiency of a ratio 0 : 3 was 56.0% with an additional yield of 0.54 t/ha.

Влияние химических фунгицидов на содержание почвенных микромицетов в агроценозе рапса ярового в центральной зоне Краснодарского края

Different soil fungi infect many agricultural crops. They cause infectious diseases of plants and can be a serious threat for crop yield that leads to significant losses in the agricultural economics all over the world. Currently, a chemical method of Brassicaceae oil crops protection is the most spread. An important technique of this method is presowing seed treatment decreasing a level of internal and external infections. Fungicides must be both effective against diseases and environmentally friendly. Currently, there is no unequivocal opinion how the chemical fungicides influence on soil microflora. The purpose of the research was to study impact of some seed protectants on an amount of suppressor fungi from species Trichoderma Pers. and pathogenic fungi from species Fusarium Link. in soil in spring rapeseed agrocenosis. The research was conducted at the V.S. Pustovoit All-Russian Research Institute of Oil Crops in 2020–2022. Before sowing, the seeds were treated with protectants with active ingredients: thiram, WSC (400 g/l) (etalon), carboxin + thiram, WSC (200 + 200 g/l), imazalil + tebuconazole, OE (100 + 60 g/l), and fludioxonil, SC (25 g/l). Soil was sampled before planting of treated rapeseed seeds and in crop phases of 2–4 true leaves and yellow pods. The soil layer from 0 to 10 cm was studied as it contains the most amount of lateral roots of this crop. To the rapeseed maturation, amounts of suppressor fungi in variants with application of preparations was at the level of the control; it increased by 1.8–2.4 × 103 CFU/g and reached 7.3–8.0 × 103 CFU/g, maximal meaning was in variant with an active ingredient fludioxonil (25 g/l). The amount of pathogenic micromycetes Fusarium spp. was by 1.7–2.0 times lower the control to the rapeseed maturation in variants with application of preparations.

Characteristics of first-time blood donors with unsatisfactory hemoglobin level and positive hepatitis B test in Binh Dinh Province

Blood transfusion is essential in the treatment of a various diseases. In order to guarantee a safe and sufficient volume of blood supply, it is crucial to select appropriate donors based on stringent eligibility criteria. The objective of this study was to furnish robust epidemiological information and identify the risk factors linked to hepatitis B virus (HBV) infection and low hemoglobin levels in first-time blood donors in Binh Dinh. Understanding the causes for donor deferrals can assist better plan and establish an efficient recruiting strategies as well as evaluate donor selection criteria. A cross-sectional study was undertaken in Binh Dinh Provincial General Hospital from November 2022 to February 2023 to examine individuals in their first-time blood donation. Data were sourced directly from voluntary blood donation registration forms. HBsAg results were assessed using rapid immunochromatographic tests and chemiluminescent immunoassays. The rate of unsatisfactory hemoglobin levels was 2.56% tested on 1,638 participants. This rate was significantly associated with female sex (18 times greater odds than males), and lower weight. The results revealed that the rate of HBV infection was 3.13% when detected by the rapid test, but increased by 0.58% when measured by chemiluminescent microparticle immunoassay. The positive hepatitis B deferral correlated with sex (p&lt;0.05), age group (p&lt;0.05) and occupation (p&lt;0.05). HBV was found the leading cause of deferral in the study area and associated with males, age groups (25–35 and 36–44), officer, worker-farmer, and self-employed people. The prevalence of low hemoglobin donor deferral obtained was 2.56%. Low hemoglobin deferral is associated with female gender, lower body weight, worker-farmer, and self-employed - others. This finding underscores a significant public health concerns, highlighting the need for strategies to lower the infection rates. Understanding the factors leading to defered donation can contribute to development of proactive strategies for recruiting and retaining donors.

Occurrence, ecology and management of Fascioloides magna in Bavaria, southern Germany

In 2015, red deer infected with American liver fluke were discovered in the Veldenstein Forest area for the first time. This was the first detection of the fluke in a wild deer population in Bavaria. The aim of the study was to determine the American liver fluke prevalence rates in red deer, roe deer and wild boar in the Veldenstein Forest, as well as factors influencing these rates. Since 2018, the livers of 83% of the red deer culled in the study area have been examined, as well as those of the occasional roe deer and wild boar. The livers are classified by adspection and dissection into four levels of infection. The age of the animals was estimated based on dentition and tooth cementum annuli in the first molar (M1). The livers of 520 red deer, 226 roe deer and 75 wild boar were dissected. All wild boar livers tested negative. 3% of roe deer and 36% of red deer livers were positive. The red deer population was reduced to lower the prevalence, beginning in 2018. In the following years, it fell significantly. Medium and high infection levels were initially detected in 61% of adult red deer. Since 2018, the median number of flukes per infected liver has decreased significantly from 17.51 flukes/liver to 10.0 flukes/liver. On driven hunts, significantly more diseased deer were found than during hunting from raised hides. Furthermore, there are close correlations between the age of the red deer, infections, and the distance from the Pegnitz floodplains. The American liver fluke leads to the extinction of roe deer locally and to a massive infection and decimation of the red deer. Without a drastic reduction in the number of infected deer populations, there is a risk of large‐scale infection of native deer species across Bavaria.

Analysis of the causes of sheep endoparasites in farms of the Luga district of the Leningrad region

This article reflects current data on the assessment of the epizootic situation for the main endoparasitoses of small cattle in two peasant (farm) farms of the Luga district of the Leningrad region with similar animal conditions. The level of extensive invasion (EI) of sheep by pathogens of parasitic diseases was established, and the age and seasonal dynamics of the spread were studied. The level of infection of livestock with strongylates of the gastrointestinal tract with an EI of 87-97%, protostrongylidoses of the genus Mullerius (M. capillaris) with EI – 53%, tapeworms of the genus Moniezia (M. expansa) – 69%, trematodes Fasciola hepatica with EI – 24-28% and eimeria with EI – 96-98%. The analysis of the causes of diseases in the territories of the studied farms was carried out, and the main mechanisms of transmission of pathogens to susceptible animals were considered. A number of violations of the conditions of keeping small cattle in the conditions of the farms under study were identified: crowded livestock, untimely change of bedding and manure cleaning, keeping young animals together with adult animals, as well as violations of microclimate conditions (reduced air velocity and increased concentration of inert gases harmful to animals). In addition, an important factor in the spread of pathogens of invasive diseases among animals on the farms under study is the deworming of livestock without taking into account the characteristics of the life cycle of parasites and the timing of their preimaginal stages, as well as the duration of endogenous and exogenous stages of development of protozoa of the Eimeria genus.Thus, causal relationships in the occurrence and circulation of pathogens of invasive diseases of small cattle among livestock in the territory of the farms of the Luga district of the Leningrad region were studied and determined, taking into account the climatic and geographical features of the area and the seasons of the year

Impact of Twig-Tip Dieback on Leaf Nutrient Status and Resorption Efficiency of Mango (Mangifera indica L.) Trees

Mineral nutrition is essential for plant growth and the interaction of plants with biotic and abiotic stresses. Mango twig-tip dieback (MTTD) is a new type of mango decline, but its impact on trees’ mineral nutrition is unknown. This study was conducted to determine the effect of MTTD infection on the nutrient status, balance, and resorption efficiency (RE) of mangoes. Leaf nutrient concentrations and deviation from the optimum percentage (DOP) indices of ‘Kensington Pride’ (KP) mango trees with low (LD) and high (HD) levels of MTTD infections were analyzed to compare the foliar nutrition status and nutrient balance between the LD and HD trees. Moreover, the nutrient resorption efficiency of MTTD-infected dried leaves (RED) was compared with the resorption efficiency of healthy (RES) leaves of KP mangoes. The concentrations of total Ca, Mg, Cu, Fe, Mn, and Zn were lower in the HD trees than in the LD trees. But the total K content was higher in the HD trees, and its DOP index was sufficient, while the total K concentration was of a low and deficient level in LD trees. Moreover, the DOP indices for total Ca, Mn, and Zn were less deficient in LD trees than in HD trees, and the overall nutrient imbalances were exacerbated in HD trees. The RED was significantly lower than RES for the total N, P, S, Cu, Fe, and Zn but significantly higher than RES for K. This study underscores the significant influence of MTTD on the mineral nutrition of KP mangoes, revealing distinct nutrient variations between trees with low and high MTTD infection levels. These findings have important implications for mango crop management, emphasizing the need for targeted nutrient interventions to address imbalances induced by MTTD and enhance the overall health and resistance of mango trees against MTTD infections.

Comparative expression profile of selected genes in Venturia inaequalis Cooke (Wint.) infecting apple fruits and leaves

Scab is a noxious fungal disease of apples (Malus domestica Borkh) in all apple producing regions caused by a host-specific phytopathogen Venturia inaequalis Cooke (Wint.). Its symptoms include black or brown lesions on leaves as well as on fruits, and causes fruit deformation. In this study, V. inaequalis was isolated from infected fruit samples and expression level of selected pathogenesis related genes in scab infected fruits and leaves was studied. The isolated fungus formed a brown coloured mat-like colony having septate mycelium and produced acute ovoid shaped conidia. Molecular characterization of the fungus was done by amplification and sequencing of internal transcribed spacer (ITS) and Cytochrome (CYP51A1) regions of the isolate. The Sanger sequencing of amplicons and sequence analysis using BLAST tool of the NCBI against GenBank database confirmed that the obtained sequence of ITS and CYP51A1 regions had 99.6 % and 98 % sequence identity with the reference V. inaequalis, respectively. The isolated strain of V. inaequalis was submitted in the fungal repository of Microbial Type Culture Collection (MTCC), India. The phylogenetic analysis of ITS region of the isolate revealed that the isolated strain of V. inaequalis was more closely related to Fusicladium eriobotryae compared to other Venturia species. The expression levels of pathogenesis related genes viz. CIN1, CE5 and VICE16 were higher in infected leaves as compared to infected fruits. Whereas expression of VICE12 and GH28 were higher in infected fruits compared to infected leaves. VICE4 gene showed equal level of expression during infection in both fruits and leaves, which was also maximum as compared to the control treatment. The transcript analysis of aforementioned genes of V. inaequalis gives the insights of the pathogen's expression profile during pathogenesis in fruits and leaves. This expression analysis can form a basis selecting pathogenesis related genes as targets for developing dsRNA expressing constructs with an aim to reduce RNAi mediated silencing of specific genes, in a futuristic biotechnological based solution to deal with apple scab disease.

PoRVA G9P[23] and G5P[7] infections differentially promote PEDV replication by reprogramming glutamine metabolism.

PoRVA and PEDV coinfections are extremely common in clinical practice. Although coinfections of PoRVA and PEDV are known to result in increased mortality, the underlying mechanism remains unknown. Here, we found that PoRVA infection promoted PEDV infection in vivo and in vitro and that PoRVA G9P[23] (RVA-HNNY strain) enhanced PEDV replication more significantly than did PoRVA G5P[7] (RVA-SXXA strain). Metabolomic analysis revealed that RVA-HNNY more efficiently induced an increase in the intracellular glutamine content in porcine small intestinal epithelial cells than did RVA-SXXA, which more markedly promoted ATP production to facilitate PEDV replication, whereas glutamine deprivation abrogated the effect of PoRVA infection on promoting PEDV replication. Further studies showed that PoRVA infection promoted glutamine uptake by upregulating the expression of the glutamine transporter protein SLC1A5. In SLC1A5 knockout cells, PoRVA infection neither elevated intracellular glutamine nor promoted PEDV replication. During PoRVA infection, the activity and protein expression levels of glutamine catabolism-related enzymes (GLS1 and GLUD1) were also significantly increased promoting ATP production through glutamine anaplerosis into the TCA cycle. Consistent with that, siRNAs or inhibitors of GLS1 and GLUD1 significantly inhibited the promotion of PEDV replication by PoRVA. Notably, RVA-HNNY infection more markedly promoted SLC1A5, GLS1 and GLUD1 expression to more significantly increase the uptake and catabolism of glutamine than RVA-SXXA infection. Collectively, our findings illuminate a novel mechanism by which PoRVA infection promotes PEDV infection and reveal that the modulation of glutamine uptake is key for the different efficiencies of PoRVA G9P[23] and PoRVA G5P[7] in promoting PEDV replication.

Test of Specificity in Signalling between Potato Plants in Response to Infection by Fusarium Solani and Phytophthora Infestans.

Plant-plant signalling via volatile organic compounds (VOCs) in response to insect herbivory has been widely studied, but its occurrence and specificity in response to pathogen attack has received much less attention. To fill this gap, we carried out a greenhouse experiment using two fungal pathogens (Fusarium solani and Phytophthora infestans) to test for specificity in VOC induction and signalling between potato plants (Solanum tuberosum). We paired potato plants in plastic cages, one acting as VOC emitter and the other as receiver, and subjected emitters to one of the following treatments: no infection (control), infected by F. solani, or infected by P. infestans. We measured total emission and composition of VOCs released by emitter plants to test for pathogen-specificity in VOC induction, and then conducted a pathogen infection bioassay to assess resistance levels on receiver plants by subjecting half of the receivers of each emitter treatment to F. solani infection and the other half to P. infestans infection. This allowed us to test for specificity in plant VOC signalling by comparing its effects on conspecific and heterospecific sequential infections. Results showed that infection by neither F. solani or P. infestans produced quantitative (total emissions) or qualitative (compositional) changes in VOC emissions. Mirroring these patterns, emitter infection treatment (control vs. pathogen infection) did not produce a significant change in pathogen infection levels on receiver plants in any case (i.e., either for conspecific or heterospecific sequential infections), indicating a lack of signalling effects which precluded pathogen-based specificity in signalling. We discuss possible mechanisms for lack of pathogen effects on VOC emissions and call for future work testing for pathogen specificity in plant-plant signalling and its implications for plant-pathogen interactions under ecologically relevant scenarios involving infections by multiple pathogens.