Prevalent Viral Disease Research Articles

Whole-genome sequencing surveillance of Siberian tick-borne encephalitis virus (TBEV) identifies an additional lineage in Kyrgyzstan.

Tick-borne encephalitis virus (TBEV) is the most prevalent tick-borne viral disease in Europe and Asia. There are three main subtypes of the virus: European, Siberian, and Far Eastern, each of which having distinctive ecology, clinical presentation, and geographic distribution. In recent years, other TBEV subtypes have been described, namely the Himalayan and Baikalian subtypes. Differences in virulence between TBEV subtypes have been described, with the Far Eastern subtype causing the most severe disease in humans. Considering the emergence of new TBEV foci, the genetic characterisation of the virus in endemic regions is crucial to not only better understand its epidemiology, but also to identify possible genetic determinants of virulence, as well as develop accurate diagnostics and therapeutics. In our previous study, we identified TBEV in six localities of the Kyrgyz Republic (Kyrgyzstan), and Ala-Archa National Nature Park as a focus of TBEV transmission. Whilst we were able to retrieve the first partial TBEV sequence from Kyrgyzstan from Ixodes persulcatus ticks, we were unable to retrieve a complete genome sequence at that time. In this study, we have utilised a sequence-independent single-primer amplification (SISPA) protocol and retrieved the complete genome sequence of our previous 2009 TBEV tick sample (strain KY09) producing the third complete TBEV genome from Kyrgyzstan, and the first genome from the region clustering within the Vasilchenko lineage, suggesting a wider distribution for the lineage than was previously thought. We have also developed a tiling amplicon scheme for Siberian TBEV (TBEV-Sib) which produced > 90 % reference coverage at 100x sequencing depths for samples with as little as 1.13×104 RNA copies/ml. Since high viral loads are rare in TBEV clinical samples, the developed protocol adds value to TBEV-Sib endemic regions by offering a novel set of primers to further amplify the viral genome prior to sequencing.

Prokaryotic Expression of Coat Protein Gene of Grapevine Berry Inner Necrosis Virus and Preparation of Its Polyclonal Antibody

Grapevine berry inner necrosis virus (GINV) and grapevine Pinot gris virus (GPGV) are prevalent viral diseases affecting viticulture, posing significant threats in grape-producing regions of China. Previous studies have emphasized the harmful effects of grape viruses on the grape industry all over the world. However, few reports have focused specifically on GINV. In wild grapevines, GINV infection frequently leads to grapevine fanleaf degeneration disease (GFDD). GINV often co-occurs with other grape viruses, exacerbating its harmful effects on the grapevine industry in China. In this study, we collected grapevine samples from Taizhou city, Jiangsu Province, where GINV infection was confirmed. Based on the GINV coat protein (CP) gene, we developed a high-throughput and high-sensitivity direct antigen-coated ELISA and Dot blot assay for field diagnosis of GINV CP in grape samples. The CP gene was cloned from GINV-infected grape samples, and the GINV CP was expressed using the pET30(a) vector. Specific polyclonal antiserum CPGINV was generated by immunizing rabbits with the purified protein, and its sensitivity was determined to be satisfactory. Leveraging the high accuracy and sensitivity of the CPGINV antiserum, we developed a rapid, precise, and scalable diagnostic method for GINV in the grapevine industry. The established ELISA and Dot blot assays successfully detected GINV-infected grapevine samples. The occurrence of GINV is relatively common in China, which poses a risk of transmission and threatens the healthy development of the grape industry. Therefore, this study prepared CPGINV antiserum and established an efficient, rapid, sensitive, accurate, and high-throughput diagnostic method, providing a foundational approach for the prevention and control of vitis viral diseases.

Canine Distemper Virus in Sardinia, Italy: Detection and Phylogenetic Analysis in Foxes.

Canine distemper virus (CDV) is the etiological agent of a highly prevalent viral infectious disease of carnivores, which could seriously lead to a threat to the conservation of the affected species worldwide [...].

Febrile Temperature Acts through HSP70-Toll4 Signaling to Improve Shrimp Resistance to White Spot Syndrome Virus.

In aquatic ectotherms, temperature plays a pivotal role in biological processes and the prevalence of viral diseases; however, the molecular mechanisms underlying these effects are not fully elucidated. In this study, we investigate the impact of elevated temperatures (32°C) on the immune response against white spot syndrome virus (WSSV) in shrimp (Litopenaeus vannamei). Our findings reveal that higher water temperatures, specifically 32°C, significantly inhibit WSSV replication and pathogenicity, thereby enhancing the survival rates of infected shrimp. Through transcriptome analysis and invivo experiments, we identified heat shock protein 70 (HSP70) as a key factor in this thermal regulation of immunity. Shrimp maintained at 32°C, with silenced HSP70 expression, exhibited increased viral loads and reduced survival, underscoring the crucial protective role of HSP70 against WSSV at elevated temperatures. Our results further uncover the HSP70-Toll4-Dorsal-antimicrobial peptide (AMP) pathway as a key mediator of WSSV resistance at elevated temperatures. This pathway involves the interaction of HSP70 with the Toll4 receptor, resulting in the phosphorylation of Dorsal and the consequent modulation of expression of AMPs such as the anti-LPS factor (ALF) and lysozyme (LYZ) families. Taken together, these findings advance our understanding of temperature's role in disease dynamics in aquatic ectotherms, especially the unexpected roles of HSP70 in shrimp in facilitating the innate immune system's response to thermal stress, and suggest new approaches to managing WSSV in shrimp farming, such as environmental temperature control or HSP70 induction.

Cotton leaf curl Multan virus subverts the processing of hydroxyproline-rich systemin to suppress tobacco defenses against insect vectors.

Insect vector-virus-plant interactions have important ecological and evolutionary implications. The constant struggle of plants against viruses and insect vectors has driven the evolution of multiple defense strategies in the host as well as counter-defense strategies in the viruses and insect vectors. Cotton leaf curl Multan virus (CLCuMuV) is a major causal agent of cotton leaf curl disease in Asia and is exclusively transmitted by the whitefly Bemisia tabaci. Here, we report that plants infected with CLCuMuV and its betasatellite CLCuMuB enhance the performance of the B. tabaci vector, and βC1 encoded by CLCuMuB plays an important role in begomovirus-whitefly-tobacco tripartite interactions. We showed that CLCuMuB βC1 suppresses the jasmonic acid signaling pathway by interacting with the subtilisin-like protease 1.7 (NtSBT1.7) protein, thereby enhancing whitefly performance on tobacco plants. Further studies revealed that in wild-type plants, NtSBT1.7 could process tobacco preprohydroxyproline-rich systemin B (NtpreproHypSysB). After CLCuMuB infection, CLCuMuB βC1 could interfere with the processing of NtpreproHypSysB by NtSBT1.7, thereby impairing plant defenses against whitefly. These results contribute to our understanding of tripartite interactions among virus, plant, and whitefly, thus offering ecological insights into the spread of vector insect populations and the prevalence of viral diseases.

Metabolomic landscape of macrophage discloses an anabolic signature of dengue virus infection and antibody-dependent enhancement of viral infection.

Dengue virus (DENV) infection causes dengue fever, the most prevalent arthropod-transmitted viral disease worldwide. Viruses are acellular parasites and obligately rely on host cell machinery for reproduction. Previous studies have indicated metabolomic changes in endothelial cell models and sera of animal models and patients with dengue fever. To probe the immunometabolic mechanism of DENV infection, here, we report the metabolomic landscape of a human macrophage cell model of DENV infection and its antibody-dependent enhancement. DENV infection of THP-1-derived macrophages caused 202 metabolic variants, of which amino acids occupied 23.7%, fatty acids 21.78%, carbohydrates 10.4%, organic acids 13.37%, and carnitines 10.4%. These metabolomic changes indicated an overall anabolic signature, which was characterized by the global exhaustion of amino acids, increases of cellular fatty acids, carbohydrates and pentoses, but decreases of acylcarnitine. Significant activation of metabolic pathways of glycolysis, pentose phosphate, amino acid metabolism, and tricarboxylic acid cycle collectively support the overall anabolism to meet metabolic demands of DENV replication and immune activation by viral infection. Totally 88 of 202 metabolic variants were significantly changed by DENV infection, 36 of which met the statistical standard (P<0.05, VIP>1.5) of differentially expressed metabolites, which were the predominantly decreased variants of acylcarnitine and the increased variants of fatty acids and carbohydrates. Remarkably, 11 differentially expressed metabolites were significantly distinct between DENV only infection and antibody-dependent enhancement of viral infection. Our data suggested that the anabolic activation by DENV infection integrates the viral replication and anti-viral immune activation.

Clinical Characteristics of Infants with Symptomatic Congenital and Postnatal Cytomegalovirus Infection-An 11-Year Multicenter Cohort Study in Taiwan.

(1) Background: Cytomegalovirus (CMV) infection is a prevalent viral disease among infants. The prevalence typically ranges from 0.2% to 2.4% among all newborns. There are limited data regarding the demographic characteristics of infants with symptomatic CMV infections. (2) Methods: In this retrospective cohort study using the Chang Gung Memorial Hospital multicenter database, infants with CMV infection determined by a positive urine culture, positive blood polymerase chain reaction assay or positive immunoglobulin M result for CMV from 2011 through 2021 were included. Clinical characteristics at initial diagnosis, management and outcomes were investigated. Congenital CMV (cCMV) infection is diagnosed within three weeks after birth; postnatal CMV (pCMV) is diagnosed when CMV is detected after the first 3 weeks of life. (3) Results: Among the 505 CMV-infected infants identified, 272 were included in the analysis. According to the age at initial presentation, 21 infants had cCMV infection and 251 had pCMV infection. Higher incidences of prematurity and being small for gestational age and a lower Z score for weight at diagnosis were observed in the cCMV group. While thrombocytopenia (61.9%) was the leading presentation in the cCMV group, hepatitis (59.8%) and prolonged jaundice (21.9%) were more common in the pCMV group. (4) Conclusions: Utilizing an 11-year multicenter database, we demonstrated the characteristics of infants with CMV infection in Taiwan and highlighted the demographic disparities and differing symptoms between the cCMV and pCMV groups. These findings emphasize the necessity for future research to refine screening policies, explore treatment options, and establish follow-up protocols for affected infants.

CCHFV vaccine development, current challenges, limitations, and future directions.

Crimean-Congo hemorrhagic fever (CCHF) is the most prevalent tick-borne viral disease affecting humans. The disease is life-threatening in many regions of the developing world, including Africa, Asia, the Middle East, and Southern Europe. In line with the rapidly increasing disease prevalence, various vaccine strategies are under development. Despite a large number of potential vaccine candidates, there are no approved vaccines as of yet. This paper presents a detailed comparative analysis of current efforts to develop vaccines against CCHFV, limitations associated with current efforts, and future research directions.

Electrocardiographic changes in dengue fever

Electrocardiographic changes in dengue fever

Long-term monitoring of aphid-transmitted viruses in melon and zucchini crops: genetic diversity and population structure of cucurbit aphid-borne yellows virus and watermelon mosaic virus.

Understanding the emergence and prevalence of viral diseases in crops requires the systematic epidemiological monitoring of viruses, as well as the analysis of how ecological and evolutionary processes combine to shape viral population dynamics. Here, we extensively monitored the occurrence of six aphid-transmitted viruses in melon and zucchini crops in Spain for 10 consecutive cropping seasons between 2011 and 2020. The most prevalent viruses were cucurbit aphid-borne yellows virus (CABYV) and watermelon mosaic virus (WMV), found in 31 and 26% of samples with yellowing and mosaic symptoms. Other viruses, such as zucchini yellow mosaic virus (ZYMV), cucumber mosaic virus (CMV), Moroccan watermelon mosaic virus (MWMV), and papaya ring spot virus (PRSV) were detected less frequently (< 3%) and mostly in mixed infections. Notably, our statistical analysis showed a significant association between CABYV and WMV in melon and zucchini hosts, suggesting that mixed infections might be influencing the evolutionary epidemiology of these viral diseases. We then carried out a comprehensive genetic characterization of the full-length genome sequences of CABYV and WMV isolates by using the PacBio single-molecule real-time high-throughput technology, in order to assess the genetic variation and structure of their populations. Our results showed that most isolates clustered in the Mediterranean clade, with a fine-scale temporal structure, which was in part explained by the level of the variance between isolates from single and mixed infections. In contrast, the WMV population genetic analysis showed that most of the isolates grouped into the Emergent clade, with no genetic differentiation.

The use of colorimetric loop-mediated isothermal amplification assay for naked-eye detection of bean common mosaic virus

Bean common mosaic virus (BCMV), one of the most prevalent viral diseases of common beans, has been intensively studied since its initial identification. In this paper, a one-step colorimetric reverse-transcription loop-mediated isothermal amplification (RT-LAMP) method was performed by designing oligonucleotide primers to amplify the gene encoding the coat protein of BCMV. Positive LAMP reactions were observed with the naked eye using WarmStart 2 × Master Mix from NEB, changing from pink to yellowish if the test is positive. The sensitivity of this method was similar to that of conventional PCR. The method was tested on common bean and another virus, bean common mosaic necrosis virus (BCMNV), and it was shown to specifically detect BCMV and not produce false positive from other RNAs. The RT-LAMP test was quite reliable for the diagnosis of BCMV from infected samples, and the precise, sensitive. The cost analysis showed that the development of a less expensive and efficient RT-LAMP assay for BCMV detection is an important step in expanding testing capacity and improving access to accurate testing in resource-limited settings. The test can be utilized in laboratory and in the field for the diagnosis and monitoring of BCMV, and is the first reported use of RT-LAMP for BCMV detection.

Prevalence of different diseases and growth performance of broilers vary with environmental variation

Abstract Broiler meat is known for its nutritional value, widespread availability, and low price. However, broilers are sensitive to environmental conditions and need a specific environment for optimum production. Global warming and natural disasters are important obstacles to broiler production. Therefore, we conducted this study during analysed the years 2019, 2020, and 2021, to reveal the broiler production status throughout the year in a subtropical region. The study area included Noakhali and Lakshimpur, located in the southern part of Bangladesh. We selected 10 smallholder broiler farms following specific conditions and collected information at the end of each month for analysis. The body weight of broilers was significantly lower in July than in other months. However, the mortality was significantly lower in July than in other months of the year. Nonetheless, the prevalence of viral disease was higher in the winter season (December, January and February). Although, the prevalence of metabolic diseases was higher in October, a high prevalence of bacterial disease was found in April. These results suggest that high temperatures decrease broiler performance while broilers are more susceptible to viral disease in the winter season.

Mucin Protein of Aedes aegypti Interacts with Dengue Virus 2 and Influences Viral Infection.

Dengue, caused by dengue virus (DENV), is the most prevalent vector-borne viral disease, posing a serious health concern to 2.5 billion people worldwide. DENV is primarily transmitted among humans by its mosquito vector Aedes aegypti; hence, the identification of a novel dengue virus receptor in mosquitoes is critical for the development of new anti-mosquito measures. In the current study, we have identified peptides which potentially interact with the surface of the virion particles and facilitate virus infection and movement during their life cycle in the mosquito vector. To identify these candidate proteins, we performed phage-display library screening against domain III of the envelope protein (EDIII), which plays an essential role during host cell receptor binding for viral entry. The mucin protein, which shared sequence similarity with the peptide identified in the screening, was cloned, expressed, and purified for in vitro interaction studies. Using in vitro pulldown and virus overlay protein-binding assay (VOPBA), we confirmed the positive interaction of mucin with purified EDIII and whole virion particles. Finally, blocking of mucin protein with anti-mucin antibodies partially reduced DENV titers in infected mosquitos. Moreover, mucin protein was found to be localized in the midgut of Ae. aegypti. IMPORTANCE Identification of interacting protein partners of DENV in the insect vector Aedes aegypti is crucial for designing vector control-based strategies and for understanding the molecular mechanism DENV uses to modulate the host, gain entry, and survive successfully. Similar proteins can be used in generating transmission-blocking vaccines.

Parasitology and Covid-19: epidemiological, immunological, pathological, and therapeutic aspects

&lt;abstract&gt; &lt;p&gt;Studies suggest that there is a complex interaction between parasitic infections, human microbiota, and host immunity. Reports have shown that there is the prevalence of viral diseases have inverse correlations with their severities (as is the case for Covid-19), their resulting mortalities, and helminth infections in endemic areas. This review study was conducted to discover the possible association between parasitic infections and Covid-19 epidemics from immunological, pathological, and therapeutic aspects. Our studies were conducted by reviewing texts, reports, and articles on reputable websites such as PubMed, Science Direct, medRxvi, Google Scholar, and bioRxiv published by 2022 07 April for keywords such as a parasite, helminth, radioactive, COVID-19 or SARS-CoV-2. In particular, reports of co-infection with helminths with complications and severity of Covid-19 in endemic areas were considered. The findings indicate that parasitic helminths can regulate host immune responses associated with a viral infection. For example, intestinal parasitic infections may be effective in reducing the symptoms of SARS-CoV-2 and the complications of Covid-19. Infected hosts can induce an innate and Th2-compatible immune response to CD4&lt;sup&gt;+&lt;/sup&gt; T cells, eosinophils, and interleukins (IL-4, IL-5, and IL-10). Chronic helminth infections prevent strong immune responses by altering the host response to T helper 2 (Th2). Interestingly, some antimalarial drugs, such as Artemisinin-based combination therapies (ACTs), may inhibit SARS-CoV-2-induced severe acute respiratory syndrome (SARS). Parasitic infections may alter the host's immune response to SARS-CoV-2 with potentially beneficial or detrimental effects. However, more large-scale epidemiological studies are needed to uncover the links between parasitic infections and COVID-19 and to clarify existing ambiguities.&lt;/p&gt; &lt;/abstract&gt;

Dynamic transcriptome analyses reveal m6A regulated immune non-coding RNAs during dengue disease progression

Dengue infection is one of the most prevalent arthropod-borne viral diseases, which can result in severe complications. Identification of genes and long non-coding RNAs (lncRNAs) involved in dengue infection would help in deciphering potential mechanisms responsible for the disease progression. We comprehensively analyzed the dynamic transcriptome during dengue disease progression and identified critical genes and lncRNAs with expression perturbations. Our findings revealed that the expression of genes (i.e., CCR10 and GNG7) and lncRNAs (i.e., CTBP1-AS and MAFG-AS1) were potentially regulated by m6A RNA methylation. Interestingly, dengue viral proteins prevalently interact with genes or lncRNAs with expression perturbations, which are involved in cell cycle, inflammation signaling pathways and immune response. Dynamically expressed genes and lncRNAs were likely to locate in the central regions of human protein-protein network, which play crucial roles in mediating signaling spread and helping viral replication. Immune microenvironments analysis revealed that plasma cells levels were increased and T cells infiltrations were decreased during dengue disease progression. Dynamically expressed genes and lncRNAs were correlated with immune cell infiltrations. Moreover, network analysis reveals the associations between dengue viral infections and human complex diseases (i.e., digestive diseases and neoplasms). Our comprehensive transcriptome analysis of dengue disease progression identified potential gene and lncRNA biomarkers, providing novel insights for understanding the pathogenesis of and developing effective therapeutic strategies for dengue infection.

Dynamic behavior of a reaction-diffusion dengue model with spatial heterogeneity

Dengue is one of the most prevalent vector-borne viral diseases, which is transmitted through the bite of Aedes mosquitoes (Aedes albopictus). In this study, using the global exponential attraction theory, the dynamic behavior of the dengue model in a spatially heterogeneous environment was studied. The existence and uniqueness of positive global solutions were proven using the semigroup theory. The basic reproduction number was defined using the spectral radius of the next-generation operator. Furthermore, a global exponential attractor set was given, and the results of globally asymptotically stable and disease uniform persistence were obtained for the dengue model. A numerical simulation showed the dynamic behavior and revealed that increasing the diffusion coefficient and spatial heterogeneity rate is beneficial for disease control.

Overexpression of a Cinnamyl Alcohol Dehydrogenase-Coding Gene, GsCAD1, from Wild Soybean Enhances Resistance to Soybean Mosaic Virus

Soybean mosaic virus (SMV) is the most prevalent soybean viral disease in the world. As a critical enzyme in the secondary metabolism of plants, especially in lignin synthesis, cinnamyl alcohol dehydrogenase (CAD) is widely involved in plant growth and development, and in defense against pathogen infestation. Here, we performed RNAseq-based transcriptome analyses of a highly SMV-resistant accession (BYO-15) of wild soybean (Glycine soja) and a SMV-susceptible soybean cultivar (Williams 82), also sequenced together with a resistant plant and a susceptible plant of their hybrid descendants at the F3 generation at 7 and 14 days post-inoculation with SMV. We found that the expression of GsCAD1 (from G. soja) was significantly up-regulated in the wild soybean and the resistant F3 plant, while the GmCAD1 from the cultivated soybean (G. max) did not show a significant and persistent induction in the soybean cultivar and the susceptible F3 plant, suggesting that GsCAD1 might play an important role in SMV resistance. We cloned GsCAD1 and overexpressed it in the SMV-susceptible cultivar Williams 82, and we found that two independent GsCAD1-overexpression (OE) lines showed significantly enhanced SMV resistance compared with the non-transformed wild-type (WT) control. Intriguingly, the lignin contents in both OE lines were higher than the WT control. Further liquid chromatography (HPLC) analysis showed that the contents of salicylic acid (SA) were significantly more improved in the OE lines than that of the wild-type (WT), coinciding with the up-regulated expression of an SA marker gene. Finally, we observed that GsCAD1-overexpression affected the accumulation of SMV in leaves. Collectively, our results suggest that GsCAD1 enhances resistance to SMV in soybeans, most likely by affecting the contents of lignin and SA.

The First Report and Phylogenetic Analysis of Canine Distemper Virus in Cerdocyon thous from Colombia.

Simple SummaryCanine distemper virus (CDV) is the etiological agent of a highly frequent viral disease of domestic and wild carnivores. It poses a threat for the conservation of endangered species. Our aim was to assess the presence and phylogenetic characterization of CDV from naturally infected Crab-eating Fox (Cerdocyon thous) from Colombia. We confirm for the first time the circulation of CDV South America/North America-4 Lineage in Crab-eating Fox. Our results are crucial for the understanding of the interspecies transmission of CDV in the domestic/wild interface and for the prevention and control of such an important multi-host pathogen.Canine distemper virus (CDV) is the etiological agent of a highly prevalent viral infectious disease of domestic and wild carnivores. This virus poses a conservation threat to endangered species worldwide due to its ability to jump between multiple species and produce a disease, which is most often fatal. Although CDV infection has been regularly diagnosed in Colombian wildlife, to date the molecular identity of circulating CDV lineages is currently unknown. Our aim was to evaluate the presence and phylogenetic characterization of CDV detected in samples from naturally infected Cerdocyon thous from Colombia. We sequenced for the first time the CDV infecting wildlife in Colombia and demonstrated the presence of South America/North America-4 Lineage with a higher relationship to sequences previously reported from domestic and wild fauna belonging to the United States of America. Our results are crucial for the understanding of the interspecies transmission of CDV in the domestic/wild interface and for the prevention and control of such an important multi-host pathogen.

Infectious hematopoietic necrosis virus promoted infectious pancreatic necrosis virus multiplication during co-infection in rainbow trout (Oncorhynchus mykiss)

Because plenty of pathogenic microbe exist in natural aquatic environments, co-infection is common. Infectious hematopoietic necrosis (IHN) and infectious pancreatic necrosis (IPN) are prevalent viral diseases in cultured salmonids, with infectious hematopoietic necrosis virus (IHNV) and infectious pancreatic necrosis virus (IPNV) known to infect rainbow trout (Oncorhynchus mykiss). To understand the influence of IHNV on IPNV in co-infection in rainbow trout, we intraperitoneally (ip) inject rainbow trout with IHNV at different time intervals prior to or after IPNV injection, and determine propagation of IPNV with absolute quantitative analysis in brain, gill, heart, liver, spleen and head kidney tissues. Meanwhile, to prove the existence and replication of IHNV in co-infections, IHNV loads were also detected by real-time quantitative polymerase chain reaction (RT-qPCR). For rainbow trout ip-injected with IHNV simultaneously or after IPNV, IPNV multiplication increases (P < 0.05) in each tissue. For rainbow trout ip-injected with IHNV 2 d prior to IPNV (H2P), levels of IPNV are enhanced (P < 0.05) in all but brain and heart tissues on 2 d post IPNV infection. For rainbow trout ip-injected with IHNV 7 d prior to IPNV (H7P), IPNV multiplication increases (P < 0.05) only in gill, heart, liver, spleen and head kidney tissues on 7 d post IPNV infection. At the same time, antiviral responses also occurred in all challenge groups. Results reveal that ip injection of IHNV simultaneously or after IPNV can enhance IPNV multiplication in in vivo co-infection, and that when ip injection of IHNV occurs prior to IPNV injection, IPNV multiplication can also be enhanced, although premature injection of IHNV does not obviously affect IPNV proliferation.

Visceral Leishmaniasis: A Case Report of a Challenging Diagnosis After Orthotopic Liver Transplantation

Leishmaniasis is a disease caused by a protozoan and transmitted by sandfly species in several emerging countries. Visceral leishmaniasis is a serious complication, especially in immunosuppressed patients, and is uncommon after liver transplantation. We report the case of a 48-year-old female patient who underwent liver transplantation owing to polycystic liver disease. Six months after the procedure, she was hospitalized with diarrhea, acute kidney failure, and leukopenia. She had been off steroids for 3 months and was taking mycophenolate and tacrolimus. She had already been treated for cytomegalovirus, which was negative on admission. During hospitalization, fever, splenomegaly, ascites, and pancytopenia appeared. Serology for Leishmania by indirect immunofluorescence was negative. Then, bone biopsy and molecular testing for Leishmania diagnosed it as visceral leishmaniasis. Amphotericin therapy was initiated with resolution of fever after 4 days of treatment and gradual recovery from pancytopenia. This case highlights the challenge of early diagnosis of visceral leishmaniasis in liver transplant recipients with diarrhea and leukopenia, which can be caused by immunosuppression or more prevalent viral diseases. Late onset of fever, splenomegaly, and a first negative serologic test also made early diagnosis difficult. The aim of the report is to emphasize the suspicion of visceral leishmaniasis in symptomatic patients from emerging countries and to question the benefit of including protozoan screening in liver transplant donors and recipients in endemic areas.