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Parasites & Vectors Jun 2023Babesia spp. are intraerythrocytic apicomplexans that digest and utilize red blood cells in a similar way to intraerythrocytic Plasmodium spp., but unlike the latter,...
Babesia spp. are intraerythrocytic apicomplexans that digest and utilize red blood cells in a similar way to intraerythrocytic Plasmodium spp., but unlike the latter, are not sensitive to artemisinin. A comparison of Babesia and Plasmodium genomes revealed that Babesia genomes, which are smaller than those of Plasmodium, lack numerous genes, and especially haem synthesis-related genes, that are found in the latter. Single-cell sequencing analysis showed that the different treatment groups of Babesia microti with expressed pentose phosphate pathway-related, DNA replication-related, antioxidation-related, glycolysis-related, and glutathione-related genes were not as sensitive to artemether as Plasmodium yoelii 17XNL. In particular, pentose phosphate pathway-related, DNA replication-related, and glutathione-related genes, which were actively expressed in P. yoelii 17XNL, were not actively expressed in B. microti. Supplying iron in vivo can promote the reproduction of B. microti. These results suggest that Babesia spp. lack a similar mechanism to that of malaria parasites through which the haem or iron in hemoglobin is utilized, and that this likely leads to their insensitivity to artemisinin.
Topics: Humans; Babesia; Artemisinins; Plasmodium yoelii; Iron; Heme; Babesiosis
PubMed: 37291657
DOI: 10.1186/s13071-023-05783-4 -
Ticks and Tick-borne Diseases Nov 2023Babesia microti is a tick-transmitted protozoan parasite of wildlife that can also cause serious disease in humans. It is now well established that B. microti represents...
Babesia microti is a tick-transmitted protozoan parasite of wildlife that can also cause serious disease in humans. It is now well established that B. microti represents an assemblage of different strains or species, only some of which are important zoonotic pathogens. Therefore, in order to assess the potential public health risk associated with B. microti in any given location, it is important to determine the strains that are present. This is the first study on the presence and identity of B. microti in Ireland. Overall, 314 wood mice (Apodemus sylvaticus), 243 bank voles (Myodes glareolus) and 634 questing Ixodes ricinus nymphs collected in various locations across Ireland were screened for the presence of B. microti by metabarcoding and nested PCR, respectively. Overall 8 rodent spleen samples (1.4%) were positive for B. microti, while all tick samples tested negative. Rodent isolates were identified as the 'Munich' strain which rarely causes human disease and is chiefly transmitted by the mouse tick, Ixodes trianguliceps. Together with reports from the UK these results suggest that B. microti does not represent a significant public health risk in Britain or Ireland.
Topics: Animals; Humans; Mice; Babesia microti; Ireland; Ixodes; Animals, Wild; Murinae; Arvicolinae
PubMed: 37406478
DOI: 10.1016/j.ttbdis.2023.102221 -
Transfusion-transmitted spp.: a changing landscape of epidemiology, regulation, and risk mitigation.Journal of Clinical Microbiology Oct 2023spp. are tick-borne parasites with a global distribution and diversity of vertebrate hosts. Over the next several decades, climate change is expected to impact humans,... (Review)
Review
spp. are tick-borne parasites with a global distribution and diversity of vertebrate hosts. Over the next several decades, climate change is expected to impact humans, vectors, and vertebrate hosts and change the epidemiology of . Although humans are dead-end hosts for tick-transmitted , human-to-human transmission of spp. from transfusion of red blood cells and whole blood-derived platelet concentrates has been reported. In most patients, transfusion-transmitted (TTB) results in a moderate-to-severe illness. Currently, in North America, most cases of TTB have been described in the United States. TTB cases outside North America are rare, but case numbers may change over time with increased recognition of babesiosis and as the epidemiology of is impacted by climate change. Therefore, TTB is a concern of microbiologists working in blood operator settings, as well as in clinical settings where transfusion occurs. Microbiologists play an important role in deploying blood donor screening assays in endemic regions, identifying changing risks for in non-endemic areas, investigating recipients of blood products for TTB, and drafting TTB policies and guidelines. In this review, we provide an overview of the clinical presentation and epidemiology of TTB. We identify approaches and technologies to reduce the risk of collecting blood products from -infected donors and describe how investigations of TTB are undertaken. We also describe how microbiologists in non-endemic regions can assess for changing risks of TTB and decide when to focus on laboratory-test-based approaches or pathogen reduction to reduce TTB risk.
Topics: Humans; United States; Babesia; Babesia microti; Blood Transfusion; Babesiosis; Blood Donors
PubMed: 37750699
DOI: 10.1128/jcm.01268-22 -
Parasites & Vectors Aug 2023The protozoan parasite Babesia microti that causes the zoonotic disease babesiosis resides in the erythrocytes of its mammalian host during its life-cycle. No effective...
BACKGROUND
The protozoan parasite Babesia microti that causes the zoonotic disease babesiosis resides in the erythrocytes of its mammalian host during its life-cycle. No effective vaccines are currently available to prevent Babesia microti infections.
METHODS
We previously identified a highly seroactive antigen, named Bm8, as a B. microti conserved erythrocyte membrane-associated antigen, by high-throughput protein chip screening. Bioinformatic and phylogenetic analysis showed that this membrane-associated protein is conserved among apicomplexan hemoprotozoa, such as members of genera Babesia, Plasmodium and Theileria. We obtained the recombinant protein Bm8 (rBm8) by prokaryotic expression and purification.
RESULTS
Immunofluorescence assays confirmed that Bm8 and its Plasmodium homolog were principally localized in the cytoplasm of the parasite. rBm8 protein was specifically recognized by the sera of mice infected with B. microti or P. berghei. Also, mice immunized with Bm8 polypeptide had a decreased parasite burden after B. microti or P. berghei infection.
CONCLUSIONS
Passive immunization with Bm8 antisera could protect mice against B. microti or P. berghei infection to a certain extent. These results lead us to hypothesize that the B. microti conserved erythrocyte membrane-associated protein Bm8 could serve as a novel broad-spectrum parasite vaccine candidate since it elicits a protective immune response against Babesiosis and Plasmodium infection.
Topics: Animals; Mice; Babesia microti; Babesia; Babesiosis; Phylogeny; Malaria; Membrane Proteins; Gastropoda; Mammals
PubMed: 37649042
DOI: 10.1186/s13071-023-05825-x -
Veterinary Microbiology Nov 2023Ticks are the main vectors for the transmission of bacterial, protist and viral pathogens in Europe affecting wildlife and domestic animals. However, some of them are... (Review)
Review
Exploring the diversity of tick-borne pathogens: The case of bacteria (Anaplasma, Rickettsia, Coxiella and Borrelia) protozoa (Babesia and Theileria) and viruses (Orthonairovirus, tick-borne encephalitis virus and louping ill virus) in the European continent.
Ticks are the main vectors for the transmission of bacterial, protist and viral pathogens in Europe affecting wildlife and domestic animals. However, some of them are zoonotic and can cause serious, sometimes fatal, problems in human health. A systematic review in PubMed/MEDLINE database was conducted to determine the spatial distribution and host and tick species ranges of a selection of tick-borne bacteria (Anaplasma spp., Borrelia spp., Coxiella spp., and Rickettsia spp.), protists (Babesia spp. and Theileria spp.), and viruses (Orthonairovirus, and flaviviruses tick-borne encephalitis virus and louping ill virus) on the European continent in a five-year period (November 2017 - November 2022). Only studies using PCR methods were selected, retrieving a total of 429 articles. Overall, up to 85 species of the selected tick-borne pathogens were reported from 36 European countries, and Anaplasma spp. was described in 37% (159/429) of the articles, followed by Babesia spp. (34%, 148/429), Borrelia spp. (34%, 147/429), Rickettsia spp. (33%, 142/429), Theileria spp. (11%, 47/429), tick-borne flaviviruses (9%, 37/429), Orthonairovirus (7%, 28/429) and Coxiella spp. (5%, 20/429). Host and tick ranges included 97 and 50 species, respectively. The highest tick-borne pathogen diversity was detected in domestic animals, and 12 species were shared between humans, wildlife, and domestic hosts, highlighting the following zoonotic species: Anaplasma phagocytophilum, Babesia divergens, Babesia microti, Borrelia afzelii, Borrelia burgdorferi s.s., Borrelia garinii, Borrelia miyamotoi, Crimean-Congo hemorrhagic fever virus, Coxiella burnetii, Rickettsia monacensis and tick-borne encephalitis virus. These results contribute to the implementation of effective interventions for the surveillance and control of tick-borne diseases.
Topics: Animals; Humans; Babesia; Encephalitis Viruses, Tick-Borne; Anaplasma; Theileria; Coxiella; Ixodes; Borrelia; Rickettsia; Animals, Domestic; Tick-Borne Diseases; Animals, Wild
PubMed: 37866329
DOI: 10.1016/j.vetmic.2023.109892 -
Infection and Immunity Oct 2023an intraerythrocytic apicomplexan parasite, is the primary causative agent of human babesiosis and an emerging threat to public health in the United States and...
an intraerythrocytic apicomplexan parasite, is the primary causative agent of human babesiosis and an emerging threat to public health in the United States and elsewhere. An effective vaccine against would reduce disease severity in acute babesiosis patients and shorten the parasitemic period in asymptomatic individuals, thereby minimizing the risk of transfusion-transmitted babesiosis. Here we report on immunogenicity, protective efficacy, and correlates of immunity following immunization with four immunodominant recombinantly produced antigens-Serine Reactive Antigen 1 (SERA1), Maltese Cross Form Related Protein 1 (MCFRP1), Piroplasm β-Strand Domain 1 (PiβS1), and Alpha Helical Cell Surface Protein 1 (BAHCS1)-delivered subcutaneously in Montanide ISA 51/CpG adjuvant in three doses to BALB/c mice. Following parasite challenge, BAHCS1 led to the highest reduction in peak parasitemia (67.8%), followed by SERA1 (44.8%) and MCFRP1 (41.9%); PiβS1 (27.6%) had minimal protective effect. All four antigens induced high ELISA total IgG and each isotype; however, antibody levels did not directly correlate with anti-parasitic activity in mice. Increased prechallenge levels of some cell populations including follicular helper T cells (T) and memory B cells, along with a set of six cytokines [IL-1α, IL-2, IL-3, IL-6, IL-12(p40), and G-CSF] that belong to both innate and adaptive immune responses, were generally associated with protective immunity. Our results indicate that mechanisms driving recombinant antigen-induced immunity are complex and multifactorial. We think that BAHCS1 warrants further evaluation in preclinical studies.
Topics: Humans; Mice; Animals; United States; Babesia microti; Babesiosis; Immunodominant Epitopes; Cytokines; Immunization
PubMed: 37728332
DOI: 10.1128/iai.00162-23 -
Clinical Infectious Diseases : An... Jun 2023Coronavirus disease 2019 (COVID-19) convalescent plasma (CCP) is a safe and effective treatment for COVID-19 in immunocompromised (IC) patients. IC patients have a...
Coronavirus disease 2019 (COVID-19) convalescent plasma (CCP) is a safe and effective treatment for COVID-19 in immunocompromised (IC) patients. IC patients have a higher risk of persistent infection, severe disease, and death from COVID-19. Despite the continued clinical use of CCP to treat IC patients, the optimal dose, frequency/schedule, and duration of CCP treatment has yet to be determined, and related best practices guidelines are lacking. A group of individuals with expertise spanning infectious diseases, virology and transfusion medicine was assembled to render an expert opinion statement pertaining to the use of CCP for IC patients. For optimal effect, CCP should be recently and locally collected to match circulating variant. CCP should be considered for the treatment of IC patients with acute and protracted COVID-19; dosage depends on clinical setting (acute vs protracted COVID-19). CCP containing high-titer severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies, retains activity against circulating SARS-CoV-2 variants, which have otherwise rendered monoclonal antibodies ineffective.
Topics: Humans; COVID-19; SARS-CoV-2; COVID-19 Serotherapy; Immunocompromised Host; Immunization, Passive; Antibodies, Viral
PubMed: 36740590
DOI: 10.1093/cid/ciad066 -
Emerging Infectious Diseases Jun 2023Babesiosis is a globally distributed parasitic infection caused by intraerythrocytic protozoa. The full spectrum of neurologic symptoms, the underlying...
Babesiosis is a globally distributed parasitic infection caused by intraerythrocytic protozoa. The full spectrum of neurologic symptoms, the underlying neuropathophysiology, and neurologic risk factors are poorly understood. Our study sought to describe the type and frequency of neurologic complications of babesiosis in a group of hospitalized patients and assess risk factors that might predispose patients to neurologic complications. We reviewed medical records of adult patients who were admitted to Yale-New Haven Hospital, New Haven, Connecticut, USA, during January 2011-October 2021 with laboratory-confirmed babesiosis. More than half of the 163 patients experienced >1 neurologic symptoms during their hospital admissions. The most frequent symptoms were headache, confusion/delirium, and impaired consciousness. Neurologic symptoms were associated with high-grade parasitemia, renal failure, and history of diabetes mellitus. Clinicians working in endemic areas should recognize the range of symptoms associated with babesiosis, including neurologic.
Topics: Adult; Humans; United States; Babesiosis; Babesia microti; Connecticut; Nervous System Diseases; Parasitemia
PubMed: 37209667
DOI: 10.3201/eid2906.221890 -
Ticks and Tick-borne Diseases Jan 2024Published data on tick-borne pathogens (TBPs) in camels worldwide have been collected to provide an overview of the global prevalence and species diversity of camelid... (Meta-Analysis)
Meta-Analysis Review
Published data on tick-borne pathogens (TBPs) in camels worldwide have been collected to provide an overview of the global prevalence and species diversity of camelid TBPs. Several TBPs have been detected in dromedary camels, raising concerns regarding their role as natural or maintenance hosts for tick-borne pathogens. Insubstantial evidence exists regarding the natural infection of camels with Babesia spp., Theileria spp., Anaplasma spp., and Ehrlichia spp., particularly because most of the camels were considered healthy at the time of sampling. Based on polymerase chain reaction (PCR) testing, a pooled prevalence of 35.3% (95% CI: 22.6-48.1%) was estimated for Anaplasma, which was the most frequently tested TBP in dromedaries, and DNA of Anaplasma marginale, Anaplasma centrale, Anaplasma ovis, Anaplasma platys, and A. platys-like were isolated, of which ruminants and dogs are reservoirs. Similarly, the estimated pooled prevalence for the two piroplasmid genera; Babesia and Theileria was approximately equal (10-12%) regardless of the detection method (microscopy or PCR testing). Nevertheless, Babesia caballi, Theileria equi, and Theileria annulata DNA have frequently been detected in camels but they have not yet been proven to be natural hosts. Scarce data detected Babesia microti, Anaplasma phagocytophilum, and Borrelia burgdorferi sensu lato (s.l.) DNA in blood of dromedaries, although ticks of the genus Ixodes are distributed in limited areas where dromedaries are raised. Interestingly, a pooled seroprevalence of 47.7% (26.3-69.2%) was estimated for Crimean-Congo hemorrhagic fever virus, and viral RNA was detected in dromedary blood; however, their contribution to maintain the viral transmission cycles requires further experimental investigation. The substantially low incidence and scarcity of data on Rickettsia and Ehrlichia species could imply that camels were accidentally infected. In contrast, camels may play a role in the spread of Coxiella burnetii, which is primarily transmitted through the inhalation of aerosols emitted by diseased animals and contaminated environments. Bactrian camels showed no symptoms due to the examined TBPs, meanwhile, clinical disease was seen in alpacas infected with A. phagocytophilum. Similar to dromedaries, accidental tick bites may be the cause of TBP DNA found in the blood of Bactrian camels.
Topics: Animals; Dogs; Camelus; Prevalence; Seroepidemiologic Studies; Ehrlichia; Rickettsia; Anaplasma; Babesia; Ixodes; Theileria annulata; DNA; Tick-Borne Diseases; Dog Diseases
PubMed: 37769585
DOI: 10.1016/j.ttbdis.2023.102268 -
Journal of Tropical Medicine 2023The current study evaluated the inhibitory effect of leaves methanolic extract (MOL) against the growth of (), , , and (), as well as growth of in mice. Active...
The current study evaluated the inhibitory effect of leaves methanolic extract (MOL) against the growth of (), , , and (), as well as growth of in mice. Active principles of MOL extract were determined using liquid chromatography mass spectrometry (LC-MS). MOL's anti-piroplasm efficacy was assessed both and using the SYBR Green I fluorescence assay. Every 96 hours, the hematological parameters, including red blood cell count (RBCs; 10/UL), hemoglobin content (HGB; g/dl), and hematocrit percent (HCT; %), in the treated mice were monitored using a Celltac MEK6450 automated hematological analyzer. LC-MS of MOL revealed that the most abundant polyphenolic catechism found in the MOL extract was isoquercetin and rutin. MOL inhibited , and growth in a dose-dependent way, with IC values of 45.29 ± 6.14, 19.16 ± 0.45, 137.49 ± 16.07, and 9.29 ± 0.014 g/ml, respectively. MOL's antibabesial activity was enhanced when administrated simultaneously with either diminazene aceturate (DA) or MMV665875 compound from malaria box. In mice infected by , a combination of MOL and a low dose of DA (12.5 mg·kg) resulted in a significant ( < 0.05) reduction in growth. These findings suggest that MOL is an effective herbal anti-piroplasm therapy, especially when combined with a low dosage of either DA or MMV665875.
PubMed: 37941580
DOI: 10.1155/2023/4285042