Evaluation of the Impact of the COVID-19 Pandemic on Cystic Echinococcosis Indirect Hemagglutination Test Dynamics: A Single-center Experience

OBJECTIVE

Cystic echinococcosis (CE) is one of the neglected tropical diseases announced by the World Health Organization. In the period entered with the Coronavirus disease-2019 pandemic, the fight against such diseases has become even more difficult. In our study, we aimed to make inferences about the effects of the pandemic on the diagnosis of the disease by evaluating the number and results of CE indirect hemagglutination test (IHA) before and during the pandemic.

METHODS

The number of IHA test requests and positivity rates in the 30-month periods before and after March 11, 2020, when the first case was seen in our country, were evaluated retrospectively. Statistical analysis was made with SPSS version 23 (SPSS, Chicago, IL, USA) program.

RESULTS

The results of 1444 patients before the pandemic and 870 patients during the pandemic period were examined. The difference between IHA positivity rates, which was found to be 18.49% before the pandemic and 14.6% during the pandemic, was statistically significant (p=0.016). The positivity rates of women and men were found to be statistically similar in both periods (pbefore=0.621, pafter=0.238). The age group with the highest IHA positivity rate was 20-39 in both periods, and the difference between the positivity rates of the age groups was statistically significant (p<0.001).

CONCLUSION

A significant decrease was observed in the rate of IHA positivity during the pandemic period. The status of no increase in positivity rates despite a significant decrease in IHA tests makes us think that the diagnosis may be missed in some patients or that there could be disruptions in their follow-up. For this reason, in order to continue the fight successfully against CE, which is an important public health problem for our country, early diagnosis and regular follow-ups should be emphasized with educations, and the laboratory-clinician communication should be strengthened in order to use tests more efficiently.

Retrospective Evaluation of Toxoplasma Serology in Patients Admitted to a Training and Research Hospital Between 2017-2021

OBJECTIVE

In this study, it was aimed to retrospectively evaluate the anti-Toxoplasma IgG, IgM and avidity index results of patients who were requested for Toxoplasma serology in our hospital between 01.01.2017 and 31.12.2021.

METHODS

Anti-Toxoplasma antibodies are studied with Abbott Architect İ2000 SR device that using the chemiluminescent microparticle immunoassay method (CMIA), according to the company's recommendations. The age, gender, nationality, sending clinic/polyclinic, and pregnancy status information of patients were scanned from the hospital system.

RESULTS

In the five-year period between 2017 and 2021, 29.58% of anti-Toxoplasma IgG tests requested from 12694 patients and 0.94% of anti-Toxoplasma IgM tests sent from 12546 patients were found positive. It is striking that the number of test requests is higher in women. IgG positivity is highest in women in the age group of 30-39 (9.97%), and in men in the age group of 60-69 (6.97%). IgM positivity is higher in both women and men in the 20-29 age group (0.48% and 0.38%, respectively). Anti-Toxoplasma IgG was positive in 27.78% and IgM in 0.64% of the pregnant women. IgG positivity in Turkish and Syrian pregnant women were determined as 25.88%; 47.10% and IgM positivity as 0.49% and 1.83%, respectively, and the difference was statistically significant (p<0.001).

CONCLUSION

Our anti-Toxoplasma antibody positivity was found to be compatible with studies conducted in different centers in our country. The fact that IgM positivity in women is high in the 20-29 age group, which is the childbearing age, emphasizes the importance of screening before and during pregnancy. Consistent with other studies in the literature, the rate of seropositivity in Syrian pregnant women was found to be higher than Turkish. This is important in terms of showing the effect of socio-cultural behaviors on prevalence.

Impact of the COVID-19 Duration on Neglected Parasitic Diseases

The Coronavirus disease-2019 (COVID-19) pandemic, which started in Wuhan, China in December 2019, has affected the whole world and caused approximately four million deaths. Consequently, scientists have done a great deal of research in such a short time about the disease. Meanwhile, parasites, whose evolutionary process is as old as human history, are often underestimated despite their high prevalence and lethality. Recent studies; however, have shown that immunity changes caused by parasitic infections affect the course of viral diseases. For example, because severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and Plasmodium use a common CD147 receptor to enter the cell and have similarities in their MHC-presented antigenic determinants, scientists suggest that immunity against parasitic infections protects the body against SARS-CoV-2 infections. This could explain the low COVID-19 incidence in malaria-endemic countries. Additionally, the cytokine storm, which is responsible for mortality in COVID-19 infections, is caused by the activation of the immune system to Th1 way. On the other hand, helminth infections, which activate the immune system to Th2 way, can reduce mortality by preventing the cytokine storm. The relationship between COVID-19 and parasites is not limited to changes in the immune system changes. Studies have shown that the pause in the fight against parasitic infections due to the diversion of all attention toward COVID-19 since the beginning of the pandemic will lead to an increase in incidences of malaria, leishmaniasis, schistosomiasis, and soil-transmitted helminths. For this reason, efforts to mitigate this increase should be resumed as soon as possible by taking additional measures globally.

Comparative Gene Expression Profiles of Leishmania major and Leishmania infantum Promastigotesa

Objective

This study aimed to determine the differences between the gene expression profiles of Leismania major and Leishmania infantum promastigotes through comparative analysis of gene expressions.

Methods

Cell culture of L. major (MHOM/IL/80) and L. infantum (MHOM/MA/67/ITMAP/263) cell lines was performed. Afterwards, total RNA isolation and cDNA synthesis were performed and fold changes in the expression levels of 30 genes that play a role in metabolic pathways and nucleic acid synthesis and co-expressed in two species were evaluated by reverse transcriptase polymerase chain reaction. Functions of genes were determined using LeishDB and KEGG databases.

Results

In this study, profiles of protein-coding 30 genes expressed in L. major and L. infantum promastigotes were evaluated and significant differences were found between the two species (p<0.001). There was a significant fold change in the expression levels of 29% of genes common in the two species. The expression levels of nine genes in L. major were found to be markedly higher than those of L. infantum (fold change >1). These genes include phosphoglycan beta 1.3 galactosyltransferase-like, lathosterol oxidase-like, fatty acid elongase, 3-oxo-5 alpha-steroid 4-dehydrogenase, calpain-like cysteine peptidase, acetyl-coA synthetase, 3'-nucleotidase/nuclease, 3'-nucleotidase/nuclease precursor and 3-ketoacyl-coA thiolase-like. When the functions of the proteins that correspond to the genes common in the two species were examined in detail using the databases, it was determined that these genes play role in lipid, protein, carbohydrate and nucleic acid metabolic functions of the parasite.

Conclusion

Alterations in the expression profiles of genes common to L. major and L. infantum species may cause differences in the virulence, pathogenesis, clinical features and treatment modality between these parasite species. In addition, evaluation of gene profiles is important in the selection of species-specific or common targets for vaccine and drug studies.

[Defining the Molecular Signal Pathways and Upstream Regulators in Cutaneous Leishmaniasis with Transcriptomic Data Approach]

Leishmaniasis is a disease caused by the genus Leishmania spp., which are intracellular parasites. Depending on parasite species and host immune response, there are three basic clinical forms of the disease: cutaneous, mucocutaneous, and visceral leishmaniasis. Cutaneous leishmaniasis is a chronic disease and characterized by the presence of ulcerated skin lesions. The type of skin pathology seen during disease is determined in part by the infecting Leishmania spp., but also by a combination of inflammatory and antiinflammatory host immune response factors resulting in diverse clinical outcomes. In this study, it was aimed to determine the genes, molecular signaling mechanisms and biological functions of the molecules that play a role in the pathogenesis of the disease and immune response and determine host-parasite interactions in mice that are naturally resistant and susceptible to Leishmania major and Leishmania braziliensis. For this, transcriptomic series GSE56029 was downloaded from "Gene Expression Omnibus"(GEO) data base, including expression profiling of twenty-four tissue samples that were recovered from both naive mice and mice (BALB/c, C57BL/6) infected with L.major and L.braziliensis. Then, "Differentially Expressed Genes" (DEGs) were identified by limma package in R script. FDR q<0.05 and absolute log2FC> 2 as threshold values were accepted in the analysis. Subsequently, functional and pathway enrichment analyses were performed for the DEGs by "Ingenuity Pathway Analysis" (IPA). For each of DEGs, p<0.01, FDR q<0.01, and absolute log2FC> 1 were used and analyzed with the software program IPA 8.0. Ingenuity Pathway Analysis revealed the most enrichment pathways to be the inflammation, dendritic cell maturation and "Triggering Receptor Expressed on Myeloid Cells 1" (TREM-1) signal mechanisms and that the DEGs related to the regulation of immune system process were closely associated with the progress of cutaneous leishmaniasis. The upstream regulator analysis predicted that TNF-α, IFNy, IL-1 β, IL-10RA and "Signal Transducer and Activator of Transcription-1" (STAT-1) are the regulators that explained gene expression changes causing biological activities in the tissues. Chemical compounds that may have anti-leishmanial effects were also identified in the study. In this study, the mechanisms belonging to the parasite species and host that determine the resistance/susceptibility phenotype were attempted to elucidate. Assessment of gene expression patterns, cytokine/chemokines, and signaling pathways in BALB/c and C57BL/6 mice infected with L.major and L.braziliensis will provide a better understanding of the potential mechanisms underlying infection from a genetic perspective. These results may guide for the future studies in terms of developing potential biomarkers for the diagnosis and prognosis prediction of cutaneous leishmaniasis and providing information about new treatment targets.

The Role of MicroRNAs in Parasitology

MicroRNAs (miRNAs), as epigenetic regulators, are small non-coding RNAs regulating gene expression in eukaryotes at the post-transcriptional level to control biological functions. MicroRNAs play a role in development, physiology, infection, immunity and the complex life cycles of parasites. Also, parasite infection can alter host miRNA expression that might result in either parasite clearance or infection. Over the past 20 years, thousands of miRNAs have been identified in the nematode Caenorhabditis elegans and other parasites. Thus, miRNA pathways are potential targets for the diagnostic and therapeutic control of parasitic diseases. Here, we review the current status and potential functions of miRNAs related to protozoans, helminths, and arthropods.