Search Results (26)

This study evaluated the effects of various concentrations of PVP-40 on the in vitro cryopreservation and recovery of Babesia bovis and Babesia bigemina. We also assessed a reduced dose of attenuated Babesia strains to determine its efficacy in preventing clinical disease. A microaerophilic stationary phase blood culture system was used to recover Babesia parasites that were cryopreserved in solutions with various PVP-40 concentrations and Babesia parasites in 20% PVP-40 were used to vaccinate naïve cattle. The animals were vaccinated intramuscularly with frozen parasites cryopreserved in 20% PVP-40, with a dose of either 1 × 10⁸ or 1 × 10⁷ erythrocytes infected with both attenuated B. bigemina and B. bovis produced from blood cultures. The control group received uninfected erythrocytes. During the vaccination, clinical parameters such as rectal temperature and hematocrit levels were unaffected. The animals were relocated to a farm in a Babesia hyperendemic area to test the efficacy of these live vaccines in controlling disease onset. Some vaccinated animals showed mild disease. In the vaccinated groups, parasites were detected in blood smears for only one day during the challenge. In contrast, the control group experienced fever for three consecutive days, a decline in hematocrit levels, and significant health deterioration. In this group, parasites were detected in smears for four consecutive days. All the animals in the control group required treatment to manage their high parasitemia and prevent mortality. In this study, we demonstrated that increasing the concentration of PVP-40 to cryopreserve parasites improved the recovery and proliferation of Babesia spp. in blood culture, and we also showed that when animals were vaccinated with cryopreserved, in vitro cultured, attenuated Babesia parasites in 20% PVP-40, they were effectively protected from severe clinical babesiosis. Full article

Babesiosis is an emerging tick-borne illness, and pulmonary manifestations have not been well described previously. This is a single-center, retrospective study of hospitalized adults with confirmed babesiosis at Westchester Medical Center (Valhalla, NY, USA) from 2006 to 2023. Descriptive analysis was used to summarize the demographic and clinical data. Logistic regression was used to determine factors associated with severe disease and mortality. A total of 147 cases were reviewed; 63 were severe, 41 were admitted to the intensive care unit, and ten died. Respiratory symptoms were observed in 42% of cases (cough, dyspnea, oxygen supplementation, respiratory failure). A total of 55 patients had an abnormal chest radiograph (infiltrates, pleural effusions), and 75% of severe cases had parasitemia ≥ 10%. Factors associated with severe cases included age ≥ 70 years, severe dyspnea, radiographic abnormalities, white blood cell count > 5000 cells/dL, hemoglobin 8 g/dL or less, and increased creatinine. Lyme seropositivity was common (28%). Exchange transfusion did not correlate with outcome. Increased mortality was more likely in patients 70 years or older or in those having any of the following: encephalopathy, acute kidney injury, severe dyspnea on admission, abnormal chest radiograph, and requiring intubation. In conclusion, pulmonary symptoms including abnormal chest radiograph are not uncommon in babesiosis and are associated with worse outcomes. Full article

Malaria is a tropical disease caused by the Plasmodium parasite, which was responsible for 249 million cases worldwide in 2022. Malaria is currently diagnosed using RDTs, PCR-based methods, or blood smear microscopy. Ideal biomarkers have been identified for malaria, with the potential for improving treatment, diagnosis, and overall clinical outcomes. This review discusses the types of existing biomarkers and the opportunities for new biomarkers to be used as diagnostic components in detecting Plasmodium, including in terms of sensitivity, detection limit, specificity, and the species of Plasmodium that can be detected. Following a comparison, five main ideal malaria biomarkers were identified, namely HRP2, pLDH, hemozoin, aldolase, and pGDH. These biomarkers distinguished themselves markedly from the others in terms of specificity in Plasmodium detection, sensitivity in analysis, and the use of non-invasive samples. Several other biomarkers, such as CRP, Ang-1, Ang-2, and PCT, show potential for malaria detection in terms of their ability to differentiate disease severity, and the levels of these biomarkers can be determined in the body for comparison with malaria parasitemia. Of the five ideal biomarkers, hemozoin and aldolase can still be developed regarding the types of samples used and their sensitivity to different Plasmodium species. Further research on the biomarkers CRP, Ang-1, Ang-2, and PCT is still needed to evaluate their potential. Full article

Reproducibly assessing malaria exposure is critical for force health protection for military service members deployed to malaria-endemic regions as well as for civilians making public health decisions and evaluating malaria eradication efforts. However, malaria disease surveillance is challenged by under-reporting, natural immunity, and chemoprophylaxis, which can mask malaria exposure and lead to an underestimation of malaria prevalence. In this study, we determined the feasibility of using a serosurveillance-based approach to measure Anopheles vector exposure, Plasmodium sporozoite exposure, and blood-stage parasitemia using a multiplex serological panel. We tested post-deployment samples obtained from U.S. service members returning from regions with malaria risk to assess the potential of this serosurveillance panel. The results identified that some service members had anti-CSP antibody levels comparable to those found in endemic populations, suggesting exposure to sporozoites while those individuals were on chemoprophylaxis. We also observed isolated cases of anti-MSP1 levels that were as high as those observed in endemic populations and in CHMI studies, suggesting possible cases of clinical or subclinical parasitemia. The study demonstrated the feasibility of implementing a multiplex serology approach for conducting serosurveillance for Anopheles vector exposure and Plasmodium parasite exposure in samples collected following military deployments and its potential to support public health policies. Full article

Agunmu (ground herbal medicine) is a form of West African traditional medicine consisting of a cocktail of herbs. The goal of this study is to evaluate a formulation of Agunmu made from M. indica, A. repens, E. chlorantha, A. boonei, and B. ferruginea, sold in the open market and commonly used for the treatment of malaria by the locals, for its antimalarial effects and to determine the active principles that may contribute to the antimalarial effect. The ethanolic extract obtained from this formulation (Ag-Iba) was analyzed, using TLC, LC-MS, and Tandem-MS techniques, to determine its phytochemical properties. The extract was tested in vitro against representative bacteria strains, cancer and normal human cell lines, and susceptible (D6) and resistant (W2) Plasmodium falciparum. In subsequent in vivo experiments, graded doses of the extract were used to treat mice infected with chloroquine-susceptible (NK-65) and chloroquine-resistant (ANKA) strains of Plasmodium berghei. Bacteria growth was monitored with a disc diffusion assay, cancer cell viability was determined with MTS assay, and percentage parasitemia and parasite clearance were determined by microscopy. Bound heme content, host mitochondria permeability transition (mPT) pore opening, F₀F₁-ATPase, and lipid peroxidation were determined via spectrophotometry. Indices of oxidative stress, anti-oxidant activities, toxicity, cell death, and inflammatory responses were obtained using biochemical and ELISA techniques. The histology of the liver and spleen was performed using the standard method. We elucidated the structures of the critical active principles in the extract to be flavonoids: kaempferol, quercetin, myricetin, and their glycosides with little or no detectable levels of the toxic Aristolochic acids that are found in Aristolochia repens, one of the components of the formulation. The extract also showed anti-plasmodial activity in in vitro and in vivo models. Furthermore, the extract dose-dependently decreased mitochondrial dysfunction, cell death, and inflammatory and oxidative damage but increased antioxidant potentials. Presumably, the active principles in the extract work as a combinatorial therapy to elicit potent antimalarial activity. Overall, our study unraveled the active components from a commercial herbal formulation that could be reformulated for antimalarial therapy. Full article

We developed and evaluated a semi-nested PCR assay for the detection of Babesia aktasi infection in goats based on the sequence of the B. aktasi 18S ribosomal RNA gene. Following in silico screening, the specificity of the primers was assessed using reference DNA samples, including B. ovis, B. motasi, B. crassa, B. venatorum, B. divergens, B. capreoli, Theileria ovis, and T. annulata. To determine the sensitivity of the method, blood infected with 2% parasitemia of B. aktasi was diluted to 10-fold serial dilutions. The method specifically amplified a 438 bp fragment of B. aktasi DNA, but did not demonstrate cross-amplification with the other hemoparasites tested. The sensitivity assay indicated that this PCR method was able to detect infection at a dilution of 10⁻⁸ of 2% parasitemia (0.074 parasites/200 µL). Ninety-seven blood samples collected from goats were used to analyze for B. aktasi, and the infection was detected in 18.5% of the goats. Additionally, the method was also applied to 44 field DNA samples that were detected to be positive for B. aktasi by reverse line blotting (RLB), and showed 84.1% agreement. The findings revealed that newly developed semi-nested PCR can detect B. aktasi infections in goats with high sensitivity and specificity. Full article

Babesia gibsoni is a parasitic protozoan transmitted through tick bites and can cause severe disease in dogs. It can also be transmitted through direct contact with infected blood during dog fights, blood transfusions, and from dam to offspring during the perinatal period, resulting in stillborn or dead newborn puppies. This study aimed to determine the incidence of infection, the viability of newborn puppies, and the degree of B. gibsoni transmission from infected dam to offspring during pregnancy and lactation. Using PCR-based molecular methods, B. gibsoni infection in a pregnant American Pit Bull Terrier and her newborn puppies was confirmed. The incidence of B. gibsoni infection in the litter reached 75%. Out of eight puppies, six were infected with B. gibsoni, and one died. A therapeutic protocol comprising Malarone^®, azithromycin, and artesunate was administered to a lactating B. gibsoni-positive bitch. By day 77 after birth, three out of five positive puppies showed negative PCR tests for B. gibsoni, indicating successful treatment through breast milk during nursing. In the two remaining positive puppies, therapy was started and parasitemia was successfully eliminated. Full article

We aimed to characterize the echocardiographic alterations in dogs from an endemic region that were naturally infected with T. cruzi. Dogs (n = 130) seropositive for antibodies against T. cruzi and/or with acute parasitemia were enrolled in the study. Indicators of changes in the structure and systolic and diastolic functions of the left ventricle (LV) and blood flow patterns were evaluated by echocardiography. The frequency and extent of alterations in these indicators were associated with the severity of the disease. Briefly, 15 (11.54%) dogs were diagnosed with dilated cardiomyopathy (DCM), and 115 (88.46%) dogs were diagnosed as being without DCM. Infected dogs with DCM exhibited structural features of LV dysfunction, e.g., a significant (p < 0.05) increase in the LV internal diameter at systole and diastole (LVID-s, LVID-d) and a decline in the LV posterior wall (LVPW-d) thickness at diastole. Despite an increase in stroke volume and cardiac output indicating contraction force, DCM resulted in a decreased ejection fraction, affecting systolic function. Dogs that were diagnosed as DCM-negative but were positive for T. cruzi by PCR exhibited a high frequency of an increase in the thickness of the interventricular septum in systole (IVS-s) and the LV posterior wall in diastole (LVPW-d), a decline in the LV inner diameter (LVID-d, LVID-s), and fractional shortening (FS). The thinning of the LVPW at systole was the most defining feature observed in chronically infected dogs. In summary, this is the first study reporting the echocardiographic changes occurring in dogs naturally infected with T. cruzi and developing DCM. Our data suggest that changes in LVID are a major indicator of risk of cardiac involvement, and the observation of changes in the IVS, LVPW, and FS have predictive value in determining the risk of DCM development in infected dogs. Full article

Maternal parasitemia and placental parasite load were examined in mother–newborn pairs to determine their effect on the congenital transmission of Trypanosoma cruzi. Parasitemia was qualitatively assessed in mothers and newborns by the microhematocrit test; parasite load was determined in the placental tissues of transmitting and non-transmitting mothers by the detection of T. cruzi DNA and by histology. Compared to transmitter mothers, the frequency and prevalence of parasitemia were found to be increased in non-transmitter mothers; however, the frequency and prevalence of parasite load were higher among the transmitter mothers than among their non-transmitter counterparts. Additionally, serum levels of interferon (IFN)-γ were measured by an enzyme-linked immunosorbent assay (ELISA) in peripheral, placental, and cord blood samples. Median values of IFN-γ were significantly increased in the cord blood of uninfected newborns. The median IFN-γ values of transmitter and non-transmitter mothers were not significantly different; however, non-transmitter mothers had the highest total IFN-γ production among the group of mothers. Collectively, the results of this study suggest that the anti-T. cruzi immune response occurring in the placenta and cord is under the influence of the cytokines from the mother’s blood and results in the control of parasitemia in uninfected newborns. Full article

Symptoms in the acute phase of Chagas disease are usually mild and nonspecific. However, after several years, severe complications like dilated heart failure and even death may arise in the chronic phase. Due to the lack of specific symptoms in the acute phase, the aim of this work was to describe and analyze the cardiac histopathology during this phase in a CD1 mouse model by assessing parasitism, fibrotic damage, and the presence and composition of a cellular infiltrate, to determine its involvement in the pathogenesis of lesions in the cardiac tissue. Our results indicate that the acute phase lasts about 62 days post-infection (dpi). A significant increase in parasitemia was observed since 15 dpi, reaching a maximum at 33 dpi (4.1 × 10⁶). The presence of amastigote nests was observed at 15–62 dpi, with a maximum count of 27 nests at 35 dpi. An infiltrate consisting primarily of macrophages and neutrophils was found in the cardiac tissue within the first 30 days, but the abundance of lymphocytes showed an 8 ≥ fold increase at 40–62 dpi. Unifocal interstitial fibrosis was identified after 9 dpi, which subsequently showed a 16 ≥ fold increase at 40–60 dpi, along with a 50% mortality rate in the model under study. The increased area of fibrotic lesions revealed progression in the extent of fibrosis, mainly at 50–62 dpi. The presence of perivasculitis and thrombus circulation disorders was seen in the last days (62 dpi); finally, cases of myocytolysis were observed at 50 and 62 dpi. These histopathological alterations, combined with collagen deposition, seem to lead to the development of interstitial fibrosis and damage to the cardiac tissue during the acute phase of infection. This study provides a more complete understanding of the patterns of histopathological abnormalities involved in the acute phase, which could help the development of new therapies to aid the preclinical tests of drugs for their application in Chagas disease. Full article

Newly emerging data suggest that several neutrophil defense mechanisms may play a role in both aggravating and protecting against malaria. These exciting findings suggest that the balance of these cells in the host body may have an impact on the pathogenesis of malaria. To fully understand the role of neutrophils in severe forms of malaria, such as cerebral malaria (CM), it is critical to gain a comprehensive understanding of their behavior and functions. This study investigated the dynamics of neutrophil and T cell responses in C57BL/6 and BALB/c mice infected with Plasmodium berghei ANKA, murine models of experimental cerebral malaria (ECM) and non-cerebral experimental malaria, respectively. The results demonstrated an increase in neutrophil percentage and neutrophil–T cell ratios in the spleen and blood before the development of clinical signs of ECM, which is a phenomenon not observed in the non-susceptible model of cerebral malaria. Furthermore, despite the development of distinct forms of malaria in the two strains of infected animals, parasitemia levels showed equivalent increases throughout the infection period evaluated. These findings suggest that the neutrophil percentage and neutrophil–T cell ratios may be valuable predictive tools for assessing the dynamics and composition of immune responses involved in the determinism of ECM development, thus contributing to the advancing of our understanding of its pathogenesis. Full article

Haemoproteus parasites (Apicomplexa, Haemosporida) are widespread pathogens of birds, with a rich genetic (about 1900 lineages) and morphospecies (178 species) diversity. Nonetheless, their life cycles are poorly understood. The exo-erythrocytic stages of three Haemoproteus majoris (widespread generalist parasite) lineages have been previously reported, each in a different bird species. We aimed to further study and compare the development of five H. majoris lineages—hCCF5, hCWT4, hPARUS1, hPHSIB1, and hWW2—in a wider selection of natural avian hosts. A total of 42 individuals belonging to 14 bird species were sampled. Morphospecies and parasitemia were determined by microscopy of blood films, lineages by DNA-barcoding a 478 bp section of the cytochrome b gene, and exo-erythrocytic stages by histology and chromogenic in situ hybridization. The lineage hCWT4 was morphologically characterized as H. majoris for the first time. All lineage infections exclusively featured megalomeronts. The exo-erythrocytic stages found in all examined bird species were similar, particularly for the lineages hCCF5, hPARUS1, and hPHSIB1. Megalomeronts of the lineages hWW2 and hCWT4 were more similar to each other than to the former three lineages. The kidneys and gizzard were most often affected, followed by lungs and intestines; the site of development showed variation depending on the lineage. Full article

Equine theileriosis, caused by Theileria haneyi and Theileria equi, leads to anemia, exercise intolerance, and occasionally, death. Theileriosis-free countries prohibit the importation of infected horses, resulting in significant costs for the equine industry. Imidocarb dipropionate is the only treatment for T. equi in the United States, but lacks efficacy against T. haneyi. The goal of this study was to assess the in vivo efficacy of tulathromycin and diclazuril against T. haneyi. Fourteen T. haneyi-infected horses were utilized. Six were treated with eight weekly 2.5 mg/kg doses of tulathromycin. Three were treated daily for eight weeks with 2.5 mg/kg diclazuril. Three were pre-treated with 0.5 mg/kg diclazuril daily for one month to determine whether low-dose diclazuril prevents infection. Following infection, the dose was increased to 2.5 mg/kg for eight weeks. Two infected horses remained untreated as controls. The horses were assessed via nested PCR, physical exams, complete blood counts, serum chemistry panels, and cytology. Tulathromycin and diclazuril failed to clear T. haneyi and the treated and control groups exhibited similar parasitemia and packed cell volume declines. To obtain additional safety data on tulathromycin use in adult horses, necropsy and histopathology were performed on tulathromycin-treated horses. No significant lesions were detected. Full article

A novel Babesia sp. infecting goats was discovered based on the molecular findings obtained in the current study, which was conducted in the Mediterranean region of Türkiye. The goal of this study was to isolate this species of Babesia (Babesia sp.) infecting goats in vivo and to assess the genetic and morphological characterization of the parasite. To identify the animal naturally infected with Babesia sp. and isolate the parasite from this animal, field studies were conducted first, and genomic DNA were extracted from blood samples taken from goats (n = 50). The Theileria, Babesia, and Anaplasma species were identified using a nested PCR-based reverse line blotting (RLB) method. The study included one goat that was determined to be infected with Babesia sp. (single infection) in RLB for in vivo isolation. A blood smear was prepared to examine the parasite’s morphology, but it was found to be negative microscopically. Following that, a splenectomy operation (to suppress the immune system) was performed to make the parasites visible microscopically in this animal. Parasitemia began after splenectomy, and the maximum parasitemia was determined to be 1.9%. The goat displayed no significant symptoms other than fever, loss of appetite, and depression. During a period when parasitemia was high, blood from this goat was inoculated into another splenectomized goat (Theileria-Babesia-Anaplasma-Mycoplasma spp. free). On the third day of inoculation, 10% parasitemia with high fever was detected in the goat, and on the fourth day, the goat was humanely euthanized due to severe acute babesiosis symptoms. Except for mild subcutaneous jaundice, no lesions were discovered during the necropsy. According to the microscopic measurement results, ring, double pyriform, spectacle-frame-like, and line forms were observed, and it was observed to be between 1.0–2.5 µm (1.38 ± 0.17 to 0.7 ± 0.21-all forms). A phylogenetic analysis and sequence comparison using the 18S rRNA and cox1 genes revealed that this species is distinct from the small ruminant Babesia species (18S rRNA 92–94%, cox1 79–80%) and has the highest similarity to Babesia sp. deer, which has been reported in deer. Furthermore, it was determined to resemble B. venatorum, B. divergens, Babesia sp. FR1 and Babesia sp. MO1 species, all of which are zoonotic. Additional research is needed to clarify the clinical status of this parasite in goats and other hosts (mountain goat, sheep, calf). Full article

Hydroxymethylnitrofurazone (NFOH) is a prodrug of nitrofurazone devoid of mutagenic toxicity, with in vitro and in vivo activity against Trypanosoma cruzi (T. cruzi) and in vitro activity against Leishmania. In this study, we aimed to increase the solubility of NFOH to improve its efficacy against T. cruzi (Chagas disease) and Leishmania species (Leishmaniasis) highly. Two formulations of NFOH nanocrystals (NFOH-F1 and NFOH-F2) were prepared and characterized by determining their particle sizes, size distribution, morphologies, crystal properties, and anti-trypanosomatid activities. Furthermore, cytotoxicity assays were performed. The results showed that the optimized particle size of 108.2 ± 0.8 nm (NFOH-F1) and 132.4 ± 2.3 nm (NFOH-F2) increased the saturation solubility and dissolution rate of the nanocrystals. These formulations exhibited moderate anti-Leishmania effects (Leishmania amazonensis) in vitro and potent in vitro activity against T. cruzi parasites (Y strain). Moreover, both formulations could reduce parasitemia (around 89–95% during the parasitemic peak) in a short animal model trial (Y strain from T. cruzi). These results suggested that the increased water solubility of the NFOH nanocrystals improved their activity against Chagas disease in both in vitro and in vivo assays. Full article