Host–Parasite Interactions

In this study, two strains of the mitochondrial lineage Q1 of Bemisia tabaci MED species, characterized by a different complement of facultative bacterial endosymbionts, were tested for their susceptibility to be attacked by the parasitoid wasp Eretmocerus mundus, a widespread natural enemy of B. tabaci. Notably, the BtHC strain infected with Hamiltonella and Cardinium was more resistant to parasitization than the BtHR strain infected with Hamiltonella and Rickettsia. The resistant phenotype consisted of fewer nymphs successfully parasitized (containing the parasitoid mature larva or pupa) and in a lower percentage of adult wasps emerging from parasitized nymphs. Interestingly, the resistance traits were not evident when E. mundus parasitism was compared between BtHC and BtHR using parasitoids originating from a colony maintained on BtHC. However, when we moved the parasitoid colony on BtHR and tested E. mundus after it was reared on BtHR for four and seven generations, we saw then that BtHC was less susceptible to parasitization than BtHR. On the other hand, we did not detect any difference in the parasitization of the BtHR strain between the three generations of E. mundus tested. Our findings showed that host strain is a factor affecting the ability of E. mundus to parasitize B. tabaci and lay the basis for further studies aimed at disentangling the role of the facultative endosymbiont Cardinium and of the genetic background in the resistance of B. tabaci MED to parasitoid attack. Furthermore, they highlight that counteradaptations to the variation of B. tabaci defence mechanisms may be rapidly selected in E. mundus to maximize the parasitoid fitness. Full article

With the birth of next-generation sequencing (NGS) technology, genomic data in public databases have increased exponentially. Unfortunately, exogenous contamination or intracellular parasite sequences in assemblies could confuse genomic analysis. Meanwhile, they can provide a valuable resource for studies of host-microbe interactions. Here, we used a strategy based on DNA barcodes to scan protistan contamination in the GenBank WGS/TSA database. The results showed a total of 13,952 metazoan/animal assemblies in GenBank, where 17,036 contigs were found to be protistan contaminants in 1507 assemblies (10.8%), with even higher contamination rates in taxa of Cnidaria (150/281), Crustacea (237/480), and Mollusca (107/410). Taxonomic analysis of the protists derived from these contigs showed variations in abundance and evenness of protistan contamination across different metazoan taxa, reflecting host preferences of Apicomplexa, Ciliophora, Oomycota and Symbiodiniaceae for mammals and birds, Crustacea, insects, and Cnidaria, respectively. Finally, mitochondrial proteins COX1 and CYTB were predicted from these contigs, and the phylogenetic analysis corroborated the protistan origination and heterogeneous distribution of the contaminated contigs. Overall, in this study, we conducted a large-scale scan of protistan contaminant in genomic resources, and the protistan sequences detected will help uncover the protist diversity and relationships of these picoeukaryotes with Metazoa. Full article

Wolbachia are obligate intracellular bacteria that occur in insects and filarial worms. Strains that infect insects have genomes that encode mobile genetic elements, including diverse lambda-like prophages called Phage WO. Phage WO packages an approximately 65 kb viral genome that includes a unique eukaryotic association module, or EAM, that encodes unusually large proteins thought to mediate interactions between the bacterium, its virus, and the eukaryotic host cell. The Wolbachia supergroup B strain, wStri from the planthopper Laodelphax striatellus, produces phage-like particles that can be recovered from persistently infected mosquito cells by ultracentrifugation. Illumina sequencing, assembly, and manual curation of DNA from two independent preparations converged on an identical 15,638 bp sequence that encoded packaging, assembly, and structural proteins. The absence of an EAM and regulatory genes defined for Phage WO from the wasp, Nasonia vitripennis, was consistent with the possibility that the 15,638 bp sequence represents an element related to a gene transfer agent (GTA), characterized by a signature head–tail region encoding structural proteins that package host chromosomal DNA. Future investigation of GTA function will be supported by the improved recovery of physical particles, electron microscopic examination of potential diversity among particles, and rigorous examination of DNA content by methods independent of sequence assembly. Full article

The spongy moth virus Lymantria dispar iflavirus 1 (LdIV1), originally identified from a Lymantria dispar cell line, was detected in 24 RNA samples from female moths of four populations from the USA and China. Genome-length contigs were assembled for each population and compared with the reference genomes of the first reported LdIV1 genome (Ames strain) and two LdIV1 sequences available in GenBank originating from Novosibirsk, the Russian Federation. A whole-genome phylogeny was generated for these sequences, indicating that LdIV1 viruses observed in North American (flightless) and Asian (flighted) spongy moth lineages indeed partition into clades as would be expected per their host’s geographic origin and biotype. A comprehensive listing of synonymous and non-synonymous mutations, as well as indels, among the polyprotein coding sequences of these seven LdIV1 variants was compiled and a codon-level phylogram was computed using polyprotein sequences of these, and 50 additional iflaviruses placed LdIV1 in a large clade consisting mostly of iflaviruses from other species of Lepidoptera. Of special note, LdIV1 RNA was present at very high levels in all samples, with LdIV1 reads accounting for a mean average of 36.41% (ranging from 1.84% to 68.75%, with a standard deviation of 20.91) of the total sequenced volume. Full article

The response of parasite communities to aquatic contamination has been shown to vary with both type of pollutant and parasite lifestyle. In this semi-experimental study, we examined uptake of pharmaceutical compounds in common carp (Cyprinus carpio L.) restocked from a control pond to a treatment pond fed with organic pollution from a sewage treatment plant and assessed changes in parasite community composition and fish biometric parameters. The parasite community of restocked fish changed over the six-month exposure period, and the composition of pharmaceutical compounds in the liver and brain was almost the same as that in fish living in the treatment pond their whole life. While fish size and weight were significantly higher in both treatment groups compared to the control, condition indices, including condition factor, hepatosomatic index, and splenosomatic index, were significantly higher in control fish. Parasite diversity and species richness decreased at the polluted site, alongside a significant increase in the abundance of a single parasite species, Gyrodactylus sprostonae. Oviparous monogeneans of the Dactylogyridae and Diplozoidae families and parasitic crustaceans responded to pollution with a significant decrease in abundance, the reduction in numbers most likely related to the sensitivity of their free-living stages to pollution. Full article

Toxoplasmosis in immunocompromised patients results in either reactivation of latent toxoplasmosis or acute infection. In the framework of the kidney transplantation program in Senegal, the serological screening of potential pre-transplant and transplanted patients can prevent the disease. This study aimed to assess the seroprevalence of toxoplasmosis in a cohort of hemodialysis patients, candidates for kidney transplantation. To this end, a multicentre cross-sectional study was conducted in 2020 in six dialysis units from five regions. Blood samples and sociodemographic data were collected from each patient. IgG and IgM against T. gondii antibodies were assessed by a chemiluminescent method using Architect ci4100, and statistical analysis was performed using R software. Overall, 211 hemodialysis patients aged from 18 to 77 years were enrolled. The mean age was 42.62 years ± 13.6, and the sex ratio M/F was 1.24. The overall seroprevalence of T. gondii was 41.7%, with the highest value being recorded in the region of Kaolack (44.4%). Patients aged over 60 years were more typically infected, at a proportion of 56.0%. Regarding sex, males elicited a higher prevalence (44.4.%) than females did. Patients of an upper socioeconomic status were less affected, and contact with cats was not associated with toxoplasmosis. By education level, the illiterate group was most affected one. Overall, this first study of toxoplasmosis among Senegalese hemodialysis patients indicates high seroprevalence. Full article

Complex interspecific relationships between parasites and their insect hosts involve multiple factors and are affected by their ecological and evolutionary context. A parasitoid Sclerodermus guani (Hymenoptera: Bethylidae) and an entomopathogenic fungus Beauveria bassiana (Hypocreales: Cordycipitaceae) shared the same host in nature, Monochamus alternatus (Coleoptera: Cerambycidae). They often encountered the semi-enclosed microhabitat of the host larvae or pupae. We tested the survival and reproduction of the parasitoid’s parent and its offspring fitness under different concentrations of B. bassiana suspension. The results show that S. guani parent females carrying higher concentrations of the pathogen shorten the pre-reproductive time and regulate their own fertility and their offspring’s survival and development. This minimal model of the interspecific interactions contains three dimensionless parameters, vulnerability (θ), dilution ratio (δ), and P_R, which were used to evaluate the mortality effect of the parasitoid S. guani on its host M. alternatus under the stress of the entomopathogenic fungus B. bassiana. We compared the infection and lethal effect of the fungus B. bassiana with different concentrations to the parasitoid S. guani and the host larvae M. alternatus. At higher concentrations of the pathogen, the parasitoid parent females shorten the pre-reproductive time and regulate their own fertility and their offspring’s survival and development. At moderate concentrations of the pathogen, however, the ability of the parasitoid to exploit the host is more flexible and efficient, possibly reflecting the potential interspecific interactions between the two parasites which were able to coexist and communicate with their hosts in ecological contexts (with a high overlap in time and space) and cause interspecific competition and intraguild predation. Full article

This study assessed the efficiency of a new in vitro tick feeding system for the adult Rhipicephalus appendiculatus tick and compared the impact of different blood anticoagulating factors on their feeding process. A total of 10 feeders were each seeded with 30 or 60 R. appendiculatus adults. Bovine blood was added into each unit and changed every 12 h for 4 to 10 days during which tick attachment and engorgement was assessed. The tick attachment observed 4 days after feeding was 80.0% (48/60), 75.8% (182/240), and 70.8% (170/240) for lithium heparin, citrate phosphate dextrose, and defibrinated blood, respectively, with no significant difference (p > 0.05) between the anticoagulants used. However, the ticks fed on heparinized and defibrinated blood reached repletion status. The in vitro tick feeding system was successfully used to feed adult R. appendiculatus ticks until repletion. This system could be used to facilitate studies on tick-pathogen interactions, such as those involved in the East Coast fever disease. Full article

Antiviral (AV) drugs are the main line of defense against pandemic influenza. However, different administration policies are applied in countries with different stocks of AV drugs. These policies lead to different occurrences of drug metabolites in the aquatic environment, altering animal behavior with evolutionary consequences on viruses. The aim of this study was to investigate the potential impact of environmental pollution by human antivirals, such as oseltamivir carboxylate (OC), on the evolutionary rate of avian influenza. We used NA, HA, NP, and MP viral segments from two groups of neighboring countries sharing migratory routes of wild birds and characterized by different AV stockpiles. BEAST analyses were performed using the uncorrelated lognormal clock evolutionary model and the Bayesian skyline tree prior model. The ratios between the rate of evolution of the NA gene and the HA, NP, and MP segments were considered. The two groups of countries were compared by analyzing the differences in the ratio distributions. Our analyses highlighted a possible different behavior in the evolution of H5N1 2.3 clade viral strains when OC environmental pollution is present. In conclusion, the widespread consumption of antivirals and their presence in wastewater could influence the selective pressure on viruses. Full article

The Zika virus pandemic of 2015, with mosquitoes Aedes aegypti and Ae. albopictus as the putative vectors, prompted public health concerns and the need to improve our understanding of both the horizontal and vertical transmission of Zika virus. Local transmission is especially concerning for Florida, where these two mosquito species are abundant and widespread throughout much of the year. Here, we evaluate the relative vertical transmission and filial infection rate of progeny of Florida Ae. aegypti and Ae. albopictus following ingestion of infected blood by parental mosquitoes at either 6 or 7 log₁₀ plaque forming units/mL of Zika virus. Florida Ae. aegypti exhibited higher rates of disseminated infection than Ae. albopictus, consistent with other studies indicating greater permissibility of Zika virus in Ae. aegypti. We observed low vertical transmission in both Ae. aegypti (1.1–3.2%) and Ae. albopictus (0–0.3%) mosquitoes, despite imbibing infected blood at titers that yielded high susceptibility to infection and modest horizontal transmission rates. Filial infection rates, testing individual mosquitoes for Ae. aegypti and Ae. albopictus, were 6–10% and 0–6.4%, respectively. Both these invasive Stegomyia mosquitoes were capable of vertically transmitting Zika virus under laboratory conditions, and approximately 5% of female progeny of Ae. aegypti were capable of transmitting Zika virus upon first bite. Full article

Yellow fever (YF) is an emerging and re-emerging arboviral disease transmitted through the bites of infected Aedes mosquitoes, primarily in the genus Aedes. Several outbreaks of yellow fever have been documented in southern Ethiopia. Four outbreaks have been documented since 2012, suggesting that southern Ethiopia is prone to YF outbreaks. Understanding the transmission cycle is pivotal to managing arboviral disease outbreaks, and the aims of the present study were to investigate the mosquito species that most likely contributed to the recent YF outbreaks and to study their behaviors. Therefore, the present study aimed to evaluate which species of Aedes mosquitoes contribute to the YF virus transmission, the outbreaks that have occurred and their behaviors (biting and resting) in the region. Two districts were selected on the basis of recent YF outbreak history. A longitudinal entomological survey was conducted to collect adult mosquitoes by using human landing catches (HLC), mechanical mouth aspirators and pyrethrum sprays. Collections were conducted twice a month for six months, from February 2019 to July 2020. The mosquitoes were identified by species by using morphological keys and molecular techniques. A total of 1689 mosquitoes were collected, of which 93.7% (1582/1689) were members of the genus Aedes and 6.3% (107/1689) of the genus Culex. A total of 58.7% (991/1689) of the mosquitoes were captured in the Ofa District and 41.3% (698/1689) from the Boko Dawula District. The largest number of mosquitoes, 97.9% (1653/1689), were collected during the wet season. A total of 1582 members of the Aedes simpsoni complex were collected, where 57.7% (913/1582) were from the Ofa District and 42.3% (669/1582) were from the Boko Dawula District. Molecular identification showed that members of the Aedes simpsoni complex accounted for 99.5% (404/406), while Aedes aegypti, detected only in the Ofa District, accounted for only 0.5% (2/406). The mosquitoes were pooled and tested for YFV, dengue virus (DENV, serotype 1–4) and chikungunya virus (CHKV) by using qPCR. None of the 934 Aedes simpsoni tested were positive for any arboviruses. The human-biting activities of Ae. simpsoni complex were peaked between 8:00–9:00 and 16:00–17:00, mostly outdoors, both within the villages and the forests. The largest numbers of Aedes simpsoni complex resting mosquitoes were collected from the leaves of the Abyssinian banana, Ensete ventricosum, suggesting that they are the preferred resting places. Although the tested Ae. simpsoni complex was negative for arboviruses; the morning and afternoon activities of the species complex coincide with peak human outdoor activities in these areas and may therefore pose the highest risk of transmitting YFV to humans. The extremely low abundance of Aedes aegypti suggests a minor role in arbovirus transmission in southern Ethiopia. It is of great importance that expanded surveillance activities of arboviruses to include reservoir hosts and sylvatic vectors to the chances of devising and implementing effective control measures. Full article

The parasitic relationship between Maculinea butterflies and Myrmica ants has been extensively studied but little information is available on the spatial occurrence of Maculinea larvae. We searched for the presence of Maculinea teleius in 211 ant nests at two sites in two crucial phases of its life cycle, i.e., in autumn, during the initial larval development, and in the following late spring, before pupation. We assessed variations in the proportion of infested nests and factors correlated with spatial distributions of parasites in Myrmica colonies. The parasitism rate in autumn was very high (∼50% of infestation rate) but decreased in the following spring. The most important factor explaining parasite occurrence in both seasons was the nest size. Further factors, such as the presence of other parasites, the Myrmica species or the site, concurred to explain the differential survival of Ma. teleius until the final development. Irrespective of the host nest distribution, the parasite distribution changed from even in autumn to clumped in late spring. Our work showed that the survival of Ma. teleius is correlated with colony features but also with the nest spatial distribution, which therefore should be taken into consideration in conservation strategies aiming at preserving these endangered species. Full article

The 22nd chromatography component (F22) of the Fasciola gigantica excretory-secretory products (FgESP) shows better diagnostic value than the FgESP, and diagnostic methods based on F22 have also been established. Thus, exploring its immunomodulatory function and potential as a molecular vaccine candidate is attractive. In the present study, the effect of F22 on the mitogen-induced proliferation of buffalo peripheral blood mononuclear cells (PBMCs) in the innate immune response was preliminarily studied using the FgESP as a control. PBMCs were incubated with concanavalin A (ConA) and phytohemagglutinin (PHA) at optimal (1 µg/well) or suboptimal (0.25 µg/well) doses coupled with FgESP and F22 at different doses (1–16 µg/well). Cell proliferation was then assessed by microenzyme reaction colorimetry (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium (MTT) assay). In addition, the components of F22 were also explored by mass spectrometry and then subjected to Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis to infer their functions. The results indicated that FgESP decreased the proliferation of PBMCs stimulated with ConA and PHA at specific doses, whereas F22 significantly decreased the proliferation of PBMCs stimulated with ConA and PHA at both optimal and suboptimal doses (p < 0.05). Two hundred and sixteen proteins were identified in F22, and these included 86 proteins that could be assigned to more than one pathway and some with robust immunomodulatory ability. Further studies should be performed to investigate the immunomodulatory function of F22 in the adaptive immune response, and the components of F22 can be further studied as potential vaccine candidate molecules. Full article

Helminth parasites secrete several types of biomolecules to ensure their entry and survival in their hosts. The proteins secreted to the extracellular environment participate in the pathogenesis and anthelmintic immune responses. The aim of this work was to identify and functionally annotate the excretory/secretory (ES) proteins of the monogenean ectoparasite Rhabdosynochus viridisi through bioinformatic approaches. A total of 1655 putative ES proteins were identified, 513 (31%) were annotated in the UniProtKB/Swiss-Prot database, and 269 (16%) were mapped to 212 known protein domains and 710 GO terms. We identified six putative multifunctional proteins. A total of 556 ES proteins were mapped to 179 KEGG pathways and 136 KO. ECPred predicted 223 enzymes (13.5%) and 1315 non-enzyme proteins (79.5%) from the secretome of R. viridisi. A total of 1045 (63%) proteins were predicted as antigen with a threshold 0.5. We also identified six venom allergen-like proteins. Our results suggest that ES proteins from R. viridisi are involved in immune evasion strategies and some may contribute to immunogenicity. Full article

The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a migratory pest endemic, to tropical and subtropical regions of America. Biological control can effectively and sustainably control pests over a long period of time while reducing the frequency of pesticide use and ensuring the safety of agricultural produce. In our study, the egg-larval Chelonus species (Chelonus bifoveolatus) from parasitized eggs of Spodoptera frugiperda in Zambia were described and identified based on morphological and genetic characteristics. To evaluate the efficiency of C. bifoveolatus, their parasitism suitability on 0- to 2-day FAW eggs under laboratory conditions was compared. The results showed that C. bifoveolatus could accept all FAW eggs at 0-, 1- and 2-day-old age and complete development successfully. Significant differences were found among 0-, 1-, and 2-day-old host eggs with respect to egg-larva developmental duration of C. bifoveolatus, and the egg-larva developmental duration on 2-day-old eggs was significantly lower than those on 0- and 1-day-old eggs. No significant differences were observed in the parasitism, pupation, emergence, and female rates for C. bifoveolatus on various age eggs of FAW. Generally, the parasitism rate, pupal rate, and emergence rate at various ages of FAW eggs were higher than 90%, 75%, and 82%, respectively, and the longevity of female parasitoids was longer than male parasitoids, and the sex ratio of females to males was nearly 1:1. Our results indicate that C. bifoveolatus performed well on various ages of FAW eggs and is a potential biological control agent against FAW in Africa. Full article

Fasciola gigantica, a giant liver fluke, causes tremendous loss to the livestock economy in several regions throughout the world. The situation of drug resistance has been emerging increasingly; therefore, novel drugs and drug targets need to be discovered. The adult F. gigantica inhabits the major bile ducts where bile salts accumulate—these are steroid-like molecules that mediate several physiological processes in organisms through interacting with their specific nuclear receptors. However, the molecular mechanism of the interaction in the parasitic organisms have not been clearly understood. In this study, putative nuclear receptor subfamily 1 of F. gigantica (FgNR1) was identified. Nucleotide and amino acid sequences of the FgNR1 homolog were obtained from the transcriptome of F. gigantica and predicted for properties and functions using bioinformatics. The full-length cDNA was cloned and expressed in the bacterial expression system and then used for immunization. Western analysis and immunolocalization suggested that FgNR1 could be detected in the crude worm antigens and was highly expressed in the caeca and testes of the adult parasite. Moreover, the bile could significantly activate the expression of FgNR1 in cultured parasites. Our results indicated that FgNR1 has high potential for the development of a novel anthelminthic drug in the future. Full article

SARS-CoV-2 belongs to the group of RNA viruses with a pronounced tendency to mutate. Omicron BA.2.75 is a subvariant believed to be able to suppress the currently dominant BA.5 and cause a new winter wave of the COVID-19 pandemic. Omicron BA.2.75 is characterized by a greater infectivity compared to earlier Omicron variants. However, the Gibbs energy of the biosynthesis of virus particles is slightly less negative compared to those of other variants. Thus, the multiplication rate of Omicron BA.2.75 is lower than that of other SARS-CoV-2 variants. This leads to slower accumulation of newly formed virions and less damage to host cells, indicating evolution of SARS-CoV-2 toward decreasing pathogenicity. Full article

Transmission dynamics and the maintenance of mammarenaviruses in nature are poorly understood. Using metagenomic next-generation sequencing (mNGS) and RT-PCR, we investigated the presence of mammarenaviruses and co-infecting helminths in various tissues of 182 Mastomys natalensis rodents and 68 other small mammals in riverine and non-riverine habitats in Zambia. The Luna virus (LUAV) genome was the only mammarenavirus detected (7.7%; 14/182) from M. natalensis. Only one rodent from the non-riverine habitat was positive, while all six foetuses from one pregnant rodent carried LUAV. LUAV-specific mNGS reads were 24-fold higher in semen than in other tissues from males. Phylogenetically, the viruses were closely related to each other within the LUAV clade. Helminth infections were found in 11.5% (21/182) of M. natalensis. LUAV–helminth co-infections were observed in 50% (7/14) of virus-positive rodents. Juvenility (OR = 9.4; p = 0.018; 95% CI: 1.47–59.84), nematodes (OR = 15.5; p = 0.001; 95% CI: 3.11–76.70), cestodes (OR = 10.8; p = 0.025; 95% CI: 1.35–86.77), and being male (OR = 4.6; p = 0.036; 95% CI: 1.10–18.90) were associated with increased odds of LUAV RNA detection. The role of possible sexual and/or congenital transmission in the epidemiology of LUAV infections in rodents requires further study, along with the implications of possible helminth co-infection. Full article

Tsetse flies are a type of blood-sucking insect living in diverse locations in sub-Saharan Africa. These insects can transmit the unicellular parasite Trypanosoma brucei (T. brucei) which causes African trypanosomiasis in mammals. There remain huge unmet needs for prevention, early detection, and effective treatments for this disease. Currently, few studies have investigated the molecular mechanisms of parasite–host interactions underlying African trypanosomiasis, mainly due to a lack of understanding of the T. brucei genome. In this study, we dissected the genomic and transcriptomic profiles of T. brucei by annotating the genome and analyzing the gene expression. We found about 5% of T. brucei proteins in the human proteome, while more than 80% of T. brucei protein in other trypanosomes. Sequence alignment analysis showed that 142 protein homologs were shared among T. brucei and mammalian genomes. We identified several novel proteins with pathogenic potential supported by their molecular functions in T. brucei, including 24 RNA-binding proteins and six variant surface glycoproteins. In addition, 26 novel microRNAs were characterized, among which five miRNAs were not found in the mammalian genomes. Topology analysis of the miRNA-gene network revealed three genes (RPS27A, UBA52 and GAPDH) involved in the regulation of critical pathways related to the development of African trypanosomiasis. In conclusion, our work opens a new door to understanding the parasite–host interaction mechanisms by resolving the genome and transcriptome of T. brucei. Full article

The Onchocercidae family is composed of more than 30 valid nematode species with notable zoonotic potential. Current limitations in molecular characterization methods and species identification are the main obstacles to a better understanding of the biology of Onchocercidae species, particularly in wildlife. This study describes for the first time the complete mitochondrial (mt) genome sequence of Neofoleyellides sp. isolated from a wild bird (Pyrrhocorax pyrrhocorax) and belonging to the Neofoleyellides genus (Nematoda: Onchocercidae). The mt genome of Neofoleyellides sp. (GenBank accession number: ON641583) was a typical circular DNA molecule of 13,628 bp in size with an AT content of 76.69%. The complete mt genome comprised 36 functional subunits, including 12 protein-coding genes (PCGs), 2 ribosomal RNA genes, and 22 transfer RNA genes. The most common start codon was ATT/ATG except for nad2 with TTG, and TAA was the termination codon for all protein-coding genes (PCGs). Phylogenetic analysis of the concatenated and aligned amino acid sequences of the 12 PCGs showed that the trees generated using different methods (Bayesian inference and maximum likelihood) with different partition schemes shared similar topologies. The isolated Neofoleyellides sp. was placed in the Onchocercidae family and formed a sister branch with the genera Onchocerca and Dirofilaria. The entire mt genome of Neofoleyellides sp. presented in this study could provide useful data for studying the population genetics and phylogenetic relationships of Onchocercidae species. Full article

Tilapia has a high socioeconomic value in many countries worldwide. However, it has been identified as a zoonotic parasite reservoir. A systematic literature search and meta-analysis were carried out in order to estimate the global prevalence of zoonotic parasites that affect tilapia. The search was performed by three field experts to avoid reviewer bias. Polled prevalence was estimated using a logistic-normal random-effect regression model in the R software. We dealt with the heterogeneity among studies through subgroup analysis, taking into account the continent, country, genus of the host, parasite taxonomic group, sample origin, and type of diagnostic test as moderator variables. Fifty-two eligible articles were identified covering five tilapia genera with a pooled prevalence of 0.14 (95% CI: 0.10–0.20) showed significant heterogeneity (I² = 98.4; p < 0.001). The subgroup analysis revealed that the most affected host was Sarotherodon, with a prevalence of 0.42 (95% CI: 0.22–0.65). Cestode was the taxonomic group with the largest prevalence (0.40; 95% CI:0.32–0.48), followed by amoeba (0.24; 95% CI: 0.16–0.35) and nematode (0.22; 95% CI: 0.11–0.38), among which, Schyzocotyle spp., Opistorchis spp., Gnathostoma spp. and Vermamoeba spp. have an impact on public health. Significant differences (p < 0.004) were found among continents and countries, with the highest value of prevalence detected in the African continent (0.28; 95% CI: 0.20–0.37), specifically in Tanzania (0.56; 95% CI: 0.22–0.87) and Egypt (0.43; 95% CI: 0.20–0.55). The origin of samples had a significant effect (p < 0.0001) on the detected prevalence, especially from those that showed the highest prevalence (0.24; 95% CI: 0.17–0.33). Finally, there were no differences in prevalence according to the diagnostic test (p = 0.97). Our results provide useful information on the development of epidemiological programs for the control of zoonoses associated with parasites in tilapia and in the design, planning, and implementation of future research. Full article

After two years into the pandemic of the coronavirus disease 2019 (COVID-19), it remains unclear how the host RNA interference (RNAi) pathway and host miRNAs regulate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and impact the development of COVID-19. In this study, we profiled small RNAs in SARS-CoV-2-infected human ACE2-expressing HEK293T cells and observed dysregulated host small RNA groups, including specific host miRNAs that are altered in response to SARS-CoV-2 infection. By comparing dysregulated miRNAs in different SARS-CoV-2-infected samples, we identified miRNA-210-3p, miRNA-30-5p, and miR-146a/b as key host miRNAs that may be involved in SARS-CoV-2 infection. Furthermore, by comparing virally derived small RNAs (vsmRNAs) in different SARS-CoV-2-infected samples, we observed multiple hot spots in the viral genome that are prone to generating vsmRNAs, and their biogenesis can be dependent on the antiviral isoform of Dicer. Moreover, we investigated the biogenesis of a recently identified SARS-CoV-2 viral miRNA encoded by ORF7a and found that it is differentially expressed in different infected cell lines or in the same cell line with different viral doses. Our results demonstrate the involvement of both host small RNAs and vsmRNAs in SARS-CoV-2 infection and identify these small RNAs as potential targets for anti-COVID-19 therapeutic development. Full article

Populations of Triatomas infestans with different susceptibility to pyrethroid insecticides were reported to have distinct evolutionary and epidemiological characteristics. We aimed at evaluating metacyclogenesis and parasite load as measures of vector competence and feeding/defecation patterns as vectorial capacity estimates of a group of resistant (“R”) and susceptible (“S”) T. infestans. Third instar nymphs of each group were fed on mice infected with Trypanosoma cruzi (Tulahuén strain, DTU VI). Parasite concentration in blood was quantified by real-time PCR (qPCR) for each mouse. The time at which feeding started, the span of feeding, the volume of blood consumed, and the time taken to defecate were measured. At 30 days post-feeding, feces were analyzed in parallel by optical microscopy (percentage of metacyclic trypomastigotes, % MT), and qPCR (total T. cruzi DNA). The ratio of parasites consumed/defecated by nymphs of each group was used to estimate the parasites’ survival and multiplication inside the triatomines’ gut. It was estimated that for each blood trypomastigote consumed, 6.6 parasites were obtained in the feces of “R” nymphs, and 7.9 in “S”. “R” nymphs consumed a higher volume of blood, had lower % MT in their feces (lower vectorial competence), and took longer to defecate (lower vectorial capacity) than “S”. Full article

Introduction: Intestinal parasites in HIV and AIDS patients increase the risk of gastroenteritis, adding to the complexity of the virus. According to the literature, their interactions are one of the factors leading to HIV replication and progression of AIDS in Africa. Chronic immunosuppression caused by HIV infection makes people vulnerable to parasitic infections, and this is associated with a CD4+ cell count of less than 100. The study describes the prevalence of intestinal parasites in patients attending HIV/AIDS clinics in certain areas of the Eastern Cape. Methods: A cross-sectional study was conducted among 600 patients from HIV/AIDS clinics in the Eastern Cape. Tambo Municipality and Amatole Municipality were the municipalities covered. These included the Ngangalizwe Community Clinic, Tsolo Gateway Clinic, Idutywa Health Centre, and Nqamakwe Health Centre. The stools of 600 participants were examined using direct wet saline/iodine embedding, formal ether concentration technique, and modified Ziehl–Neelsen methods. Results: The mean age of the study participants was 28.2 years. They were predominantly female (79.9%), mostly single (63.6%), and lived in rural (65.2%) and urban areas (34.8%). The prevalence of intestinal parasites was determined to be 30% (180/600) after screening 600 stool samples. The most frequently detected parasites were Ascaris lumbricoides (55.9%), Balantidium coli (15.1%), Entamoeba coli (11.3%), Diphyllobothrium latum (4.3%), Taenia species (3.8%), Schistosoma mansoni (1.6%), and Cryptosporidium spp. (1.6%). Males were affected more frequently (39.2%) than females (27.9%). The difference was statistically significant (p = 0.017). Among the identified intestinal parasites, A. lumbricoides, B. coli, and Taenia spp. were found at all four sites. Conclusion: This study has shed light on the high burden of intestinal parasites in HIV/AIDS patients in the Eastern Cape. Medication adherence, deworming, and sanitary hygiene practices are needed to enhance the control of infection in the affected communities and hence contribute to the control of the HIV pandemic. Full article

Resistant variety screening is widely recommended for the management of Sitobion avenae. The purpose of this study was to assess responses of six wheat varieties (lines) to S. avenae. The aphid quantity ratio (AQR) was used to assess S. avenae resistance. Pearson’s correlation coefficient was used to perform a correlation analysis between AQR, biological parameters, and the accumulation of total phenolic and flavonoid content. When compared to the other cultivars, the results showed that two cultivars, Yongliang No.15 and Ganchun No.18, had high resistance against S. avenae. The correlation analysis revealed a positive relationship between total phenol and flavonoid content accumulation and developmental duration (DD), and a negative relationship between accumulation and weight gain (WG) and mean relative growth rate (MRGR). The correlation between flavonoid and biological parameters was statistically stronger than the correlation between total phenol and biological parameters. This research provides critical cues for screening and improving aphid-resistant wheat varieties in the field and will aid in our understanding of the resistance mechanism of wheat varieties against S. avenae. Full article

Feline trichomonosis occurs worldwide, with gastrointestinal symptoms such as chronic large-bowel diarrhea and abdominal pain. The inclusion of molecular methods in diagnostic and epidemiological studies has necessitated an effective method for extracting DNA from feces. We tested four extraction commercial kits: ZR Fecal DNA MiniPrep (50 preps) (Zymo Research, Irvine, CA, USA), QIAamp^® DNA Stool Mini Kit (Qiagen Inc., Valencia, CA, USA), UltraClean Fecal DNA Kit (50 preps) (MO BIO, San Diego, CA, USA), and Sherlock AX/100 isolations (A&A Biotechnology, Gdynia, Poland). We assessed the sensitivity of detection of Tritrichomonas foetus in spiked fecal samples for the four kits combined with two molecular assays: PCR and LAMP. The extraction efficacy was quantified using defined aliquots of fecal samples spiked with 5 μL of suspensions containing serial dilutions of trophozoites (0.1; 1; 10; 100; 1000; 10,000), with six replicates for each concentration. In our study, we proved that the ZR Fecal DNA MiniPrep (50 preps) kit combined with LAMP and PCR had the highest efficiency among all the compared methods for the detection of feline T. foetus from fecal samples. Full article