Risk of transfusion-transmitted Babesia microti in Canada.

BACKGROUND: Babesia microti has gained a foothold in Canada as tick vectors become established in broader geographic areas. B. microti infection is associated with mild or no symptoms in healthy individuals but is transfusion-transmissible and can be fatal in immunocompromised individuals. This is the first estimate of clinically significant transfusion-transmitted babesiosis (TTB) risk in Canada. STUDY DESIGN AND METHODS: The proportion of B. microti-antibody (AB)/nucleic acid amplification test (NAT)-positive whole blood donations was estimated at 5.5% of the proportion of the general population with reported Lyme Disease (also tick-borne) based on US data. Monte Carlo simulation estimated the number and proportion of infectious red cell units for three scenarios: base, localized incidence (risk in Manitoba only), and donor study informed (prevalence from donor data). The model simulated 1,029,800 donations repeated 100,000 times for each. RESULTS: In the base scenario 0.5 (0.01, 1.75), B. microti-NAT-positive donations would be expected per year, with 0.08 (0, 0.38) recipients suffering clinically significant TTB (1 every 12.5 years). In the localized incidence scenario, there were 0.21(0, 0.7) B. microti-NAT-positive donations, with 0.04 (0, 0.14) recipient infections (about 1 every 25 years). In the donor study informed scenario, there were 4.6 (0.3, 15.8) B. microti-NAT-positive donations expected, and 0.81 (0.05, 3.14) clinically significant TTB cases per year. DISCUSSION: The likelihood of clinically relevant TTB is low. Testing would have very little utility in Canada at this time. Ongoing pathogen surveillance in tick vectors is important as B. microti prevalence appears to be slowly increasing in Canada.

Transfusion-associated babesiosis in China: A case report.

Babesiosis, a novel zoonosis, is endemic in the Northeast and Midwest United States. This disease is primarily transmitted by ticks and less commonly transmitted through blood transfusion. Here, we present a case of human babesiosis of unknown etiology. The patient may have been infected through blood transfusion. This patient had fever for more than 1 month, accompanied by fatigue, anemia, jaundice, and other symptoms. Clinical improvement was unsatisfactory with antibiotics. Subsequently, peripheral blood smears showed many circulating forms of parasites,morphologically consistent with Babesia in red blood cells. Gene sequencing suggested Babesia microti. We treated the patient with azithromycin combined with other symptomatic supportive treatment. Finally, the patient recovered and was discharged. The intensity of babesiosis ranges from mild to severe and can be fatal, so early diagnosis and treatment are warranted.

Transfusion transmitted babesiosis: A systematic review of reported cases.

BACKGROUND: Transfusion transmitted babesiosis (TTB) has a high mortality rate but may go unrecognized, particularly in non-endemic areas. We therefore conducted a systematic review to better characterize clinical aspects of TTB. METHODS: A literature search was conducted in PubMed and CINAHL databases, from which 25 eligible articles describing 60 TTB patients met criteria for data extraction. RESULTS: Symptom evaluation was provided for 25 implicated donors: 18/25 (72%) were asymptomatic while 7/25 (28%) had mild flu-like symptoms but were asymptomatic at time of donation. It was common for a single donor or donation to infect multiple patients. Where reported, species included B. microti - 54/60 (90%), B. duncani - 3/60 (5%), and B. divergens-like/MO-1 - 1/60 (2%). Most TTB patients (44/60, 73%) resided in endemic states, while most TTB deaths 6/9 (67%) occurred in non-endemic states. Severity of hemolysis was proportional to degree of parasitemia. Mortality in our series was 9/60 (15%); most deaths occurred at extremes of the age spectrum: 6/9 non-survivors were aged >55 years, 2/9 were <1 year, only 1/9 was 2-54 years. Number of comorbidities was higher among non-survivors (median = 4) compared to survivors (median = 1). CONCLUSIONS: All implicated donors (for which symptoms data were reported) resulting in TTB infections were asymptomatic at the time of donation, and it was common for a single donor or donation to infect multiple patients. Mortality of TTB appeared highest among those with more comorbidities and in non-endemic states. Heightened awareness of this diagnosis is key in its recognition.

Repeat exchange transfusion for treatment of severe babesiosis.

We report a case of severe babesiosis presenting with 43% parasitemia in a 73-year-old splenectomized woman on etanercept for rheumatoid arthritis. She initially was treated aggressively with clindamycin and quinine and exchange transfusion. Despite a post-exchange drop in parasitemia to 7.6%, it rebounded to 11.4% on hospital day 5 accompanied by new onset high fevers and hypoxia. She improved after a second exchange transfusion and ultimately resolved her infection after 12 weeks of antibabesial antibiotics. Although exchange transfusion is commonly used in immunocompromised hosts, there is a dearth of information about repeat exchange transfusion, including the risk for and outcome of repeat exchange. We performed a literature search for other cases of repeat exchange transfusion for severe Babesia microti infection and compared our case with those in other published reports.

Clinical Occurrence of Canine Babesiosis in the Coastal Area of the Black Sea (Dobrogea) in Southeastern Romania and Associated Epidemiological Implications.

Canine babesiosis (CB) is a significant tick-borne disease caused by intra-erytrocytic protozoa of the genus Babesia (Apicomplexa: Piroplasmida) and is currently emerging or re-emerging in many European countries. Despite the increasing incidence of clinical CB, little is known of the epidemiology of this disease in Romania. Therefore, the present study was conducted to provide epidemiological data on CB in the coastal area of the Black Sea (Dobrogea), southeastern Romania. For this, 306 owned dogs presented during 2016-2018 at a veterinary clinic in the area and clinically suspected for CB were tested for the presence of intra-erytrocytic piroplasms using Giemsa-stained thin blood smears. Overall, 27.8% (95% CI: 22.83-33.16) of dogs were positive for large piroplasms. The Babesia spp.-positive dogs were 51 males and 34 females aged from 3 mo to 13 yr (mean 4.2 yr; SD = 3.6). A higher rate of infection was registered in Bichon Maltese (n = 13) and mixed-breed (n = 28) dogs. Most cases (76/85; 89.4%) were diagnosed from March to June, with only a few cases registered in November and December (1 case each). Infected dogs displayed different clinical presentations, varying from mild (38.8%) to moderate (29.4%) and severe disease (29.4%). Based on clinical- pathological changes, 38 (44.7%), 34 (40.0%), and 13 (15.3%) dogs were diagnosed with uncomplicated babesiosis, complicated babesiosis with a single organ dysfunction, and complicated babesiosis with multiple-organ-dysfunction syndrome (MODS), respectively. The recovery rate (81.6%, 70.1%, and 38.4%, respectively) was significantly different in these groups. The age of dogs appeared to be a risk factor for both severe disease (mean age of 5.8 yr) and MODS (mean age 6.8 yr). These findings document the common occurrence of CB in Dobrogea, southeastern Romania, and suggest that appropriate control measures need to be taken.

Transfusion-Transmitted Infections Reported to the National Healthcare Safety Network Hemovigilance Module.

Transfusion-transmitted infections (TTIs) can be severe and result in death. Transfusion-transmitted viral pathogen transmission has been substantially reduced, whereas sepsis due to bacterial contamination of platelets and transfusion-transmitted babesiosis may occur more frequently. Quantifying the burden of TTI is important to develop targeted interventions. From January 1, 2010, to December 31, 2016, health care facilities participating in the National Healthcare Safety Network Hemovigilance Module monitored transfusion recipients for evidence of TTI and recorded the total number of units transfused. Facilities use standard criteria to report TTIs. Incidence rates of TTIs, including for bacterial contamination of platelets and transfusion-transmitted babesiosis, are presented. One hundred ninety-five facilities reported 111 TTIs and 7.9 million transfused components to the National Healthcare Safety Network Hemovigilance Module. Of these 111 reports, 54 met inclusion criteria. The most frequently reported pathogens were Babesia spp in RBCs (16/23, 70%) and Staphylococcus aureus in platelets (12/30, 40%). There were 1.95 (26 apheresis, 4 whole blood derived) TTIs per 100 000 transfused platelet units and 0.53 TTI per 100 000 transfused RBC components, compared to 0.68 TTI per 100 000 all transfused components. Bacterial contamination of platelets and transfusion-transmitted babesiosis were the most frequently reported TTIs. Interventions that reduce the burden of bacterial contamination of platelets, particularly collected by apheresis, and Babesia transmission through RBC transfusion would reduce transfusion recipient morbidity and mortality. These analyses demonstrate the value and importance of facility participation in national recipient hemovigilance using standard reporting criteria.

Tissue and blood protozoa including toxoplasmosis, Chagas disease, leishmaniasis, Babesia, Acanthamoeba, Balamuthia, and Naegleria in solid organ transplant recipients- Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice.

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention, and management of tissue and blood protozoal infections in the pre- and post-transplant period. Significant new developments in the field have made it necessary to divide the previous single guideline published in 2013 into two sections, with the intestinal parasites separated from this guideline devoted to tissue and blood protozoa. The current update reflects the increased focus on donor screening and risk-based recipient monitoring for parasitic infections. Increased donor testing has led to new recommendations for recipient management of Toxoplasma gondii and Trypanosoma cruzi. Molecular diagnostics have impacted the field, with access to rapid diagnostic testing for malaria and polymerase chain reaction testing for Leishmania. Changes in Babesia treatment regimens in the immunocompromised host are outlined. The risk of donor transmission of free-living amebae infection is reviewed. Changing immigration patterns and the expansion of transplant medicine in developing countries has contributed to the recognition of parasitic infections as an important threat to transplant outcomes. Medications such as benznidazole and miltefosine are now available to US prescribers as access to treatment of tissue and blood protozoa is increasingly prioritized.

Rare, Uncommon, and Unusual Complications After Pancreaticoduodenal Resection.

Complications after pancreaticoduodenal resection occur in at least 30% of patients. Most are a direct result of an intraoperative event, dissection, or anastomoses which account for the most serious morbidities, sepsis, pseudoaneurysms, and hemorrhage. Rarely, complications are due to the systemic impact of the procedure even if the procedure itself was unremarkable. Rare systemic complications after PDR (Transfusion transmitted Babesiosis, pituitary apoplexy, and TRALI) and a number of uncommon and unusual other complications are discussed. Pancreaticoduodenal resection is a significant operation with serious consequences. Decisions on selection of candidates and safe operations should be thoughtful and always in surgeons' minds.

Babesiosis: An unusual cause of sepsis after kidney transplantation and review of the literature.

We report a unique case of babesiosis presenting as sepsis after kidney transplantation. A 70-year-old female kidney transplant recipient presented with fever, hemolytic anemia, and acute kidney injury, and met three of four systemic inflammatory response syndrome criteria. Serology was positive for Babesia microti, confirmed by polymerase chain reaction. The patient was treated with atovaquone and azithromycin and made a full recovery. Reports of babesiosis after solid organ transplantation are rare, with only four prior cases reported in the literature. We report the first case of babesiosis, to our knowledge, presenting as sepsis that was successfully treated after solid organ transplantation.

Canine tick-borne pathogens and associated risk factors in dogs presenting with and without clinical signs consistent with tick-borne diseases in northern Australia.

OBJECTIVES: To estimate the proportion of canine tick-borne disease (CTBD) pathogens in dogs from northern states of Australia presenting with and without clinical signs/laboratory abnormalities suggestive of CTBD and to evaluate associated risk factors. DESIGN: Client-owned dogs presented to a general practice clinic in the Northern Territory (NT; n = 138) and five referral hospitals in south-east Queensland (SEQ; n = 100) were grouped into CTBD-suspect and -control groups based on clinical and laboratory criteria. Blood and sera were screened for haemotropic Mycoplasma spp., Babesia spp., Anaplasma spp., Ehrlichia spp. and Hepatozoon spp. using microscopic examination, in-clinic ELISA testing and PCR assays. Dog-specific risk factors associated with the presence of CTBD pathogens were evaluated. RESULTS: Overall, 24.4% of the suspect group and 12.2% of the control group dogs were infected. The proportions of M. haemocanis, B. vogeli, A. platys, Candidatus Mycoplasma haematoparvum, and C. Mycoplasma haemobos were 7.1%, 5.0%, 3.8%, 1.7% and 0.4%, respectively. Dogs originating from the NT were 3.6-fold (95% confidence interval (CI) 1.51-8.62; P = 0.004) more likely to be infected with CTBD pathogens than those from SEQ. Male dogs were 2.3-fold (95% CI 1.17-4.80, P = 0.024) more likely to be PCR-positive to CTBD pathogens than female dogs. Dogs presenting with clinical signs consistent with CTBD and thrombocytopenia were more likely to be infected by CTBD pathogens (odds ratio 2.85; 95% CI 1.16, 7.02; P = 0.019). CONCLUSIONS: Haemotropic mycoplasmas were the most common tick-borne pathogen infecting client-owned dogs. Subclinical cases were common in dogs from the NT. Veterinary practitioners should be aware of the proportion of CTBD pathogens and the presenting features of clinical and subclinical disease in their area.

First report of Babesia divergens infection in an HIV patient.

Human babesiosis is a zoonosis primarily transmitted through Ixodes ticks and alternatively by routes such as blood transfusions from asymptomatic donors. We report the first case of human babesiosis caused by Babesia divergens in a patient with HIV. This study also focuses on elucidating the possible transmission route of infection in this patient, who received numerous blood transfusions but showed patent symptoms only after splenectomy. A battery of detection tools along with a novel Western-Blot Assay and Enzyme Linked Immunosorbent Assay using the major surface protein of B. divergens (Bd37) as a target were used to evaluate the presence of B. divergens or antibodies against the parasite in samples from the patient and the blood donors involved in this case. A retrospective study of the humoral status against the parasite revealed B. divergens IgG antibodies in one of the implicated donors, but also showed that the patient had been already exposed to the parasite before any transfusion. Thus, this analysis of natural and transfusion transmission routes suggests a pre-existing subclinical babesiosis in the patient.

Models of bovine babesiosis including juvenile cattle.

Bovine Babesiosis in cattle is caused by the transmission of protozoa of Babesia spp. by ticks as vectors. Juvenile cattle (<9 months of age) have resistance to Bovine Babesiosis, rarely show symptoms, and acquire immunity upon recovery. Susceptibility to the disease varies between breeds of cattle. Models of the dynamics of Bovine Babesiosis transmitted by the cattle tick that include these factors are formulated as systems of ordinary differential equations. Basic reproduction numbers are calculated, and it is proved that if these numbers are below the threshold value of one, then Bovine Babesiosis dies out. However, above the threshold number of one, the disease may approach an endemic state. In this case, control measures are suggested by determining target reproduction numbers. The percentage of a particular population (for example, the adult bovine population) needed to be controlled to eradicate the disease is evaluated numerically using Columbia data from the literature.

Risk assessment of transfusion-associated babesiosis in Tyrol: appraisal by seroepidemiology and polymerase chain reaction.

BACKGROUND: After malaria, babesiosis is the second most common transfusion-transmitted parasitic disease in the United States. In Europe, one reported transfusion case, concerning Babesia microti, occurred in Germany. STUDY DESIGN AND METHODS: Due to the fact that Babesia spp. are present in Tyrolean ticks, the aim of this study is to assess the occurrence of immunoglobulin (Ig)G antibodies against the Babesia divergens complex, including B. divergens and Babesia venatorum (EU1), as well as B. microti by screening a representative collective of 988 blood donors from North and East Tyrol (Austria) with indirect immunofluorescence antibody test. Additionally, we investigated 206 local ixodid ticks for the presence of babesial DNA by polymerase chain reaction. RESULTS: Seroprevalence data resulted in rates of 2.1% for IgG antibodies against the B. divergens complex and 0.6% against B. microti in Tyrolean blood donors. All sera could be confirmed by independent retesting. Our data indicate that cross-reactivity is high between B. divergens and B. venatorum and lower than 19.8% between B. divergens and B. microti. CONCLUSIONS: This study shows that Babesia spp. are present in the Tyrols, which blood donors come into serologic contact with, and that we have to consider how to sustain blood product safety concerning this new challenge. Additionally, it is the first description of B. venatorum in the Tyrols, found in one Ixodes ricinus at the Italian border.

Environmental investigation following the first human case of babesiosis in Tennessee.

Babesiosis is an emerging tick-borne zoonotic disease in the United States caused by Babesia parasites. In 2009, the first case of babesiosis was documented in Tennessee. Environmental investigation at the reported site of tick exposure included collection of ticks and specimens from eastern cottontail rabbits (Sylvilagus floridanus) and white-tailed deer ( Odocoileus virginianus ) that were tested for piroplasms by molecular and serologic methods. One hundred and sixty-six Ixodes scapularis ticks and biological samples from 8 rabbits and 5 deer were collected. Ixodes scapularis were PCR positive for Babesia odocoilei (n = 7, 4%) and Theileria cervi (n = 24, 14%). Deer were seropositive for B. odocoilei and PCR positive for T. cervi. Rabbits were seropositive for B. odocoilei and Babesia sp. MO1, and 1 rabbit was PCR positive for Babesia sp. MO1. In summary, zoonotic Babesia sp. MO1 infection in rabbits is reported here for the first time in Tennessee as well as infection of deer and I. scapularis ticks with 2 other piroplasms of veterinary importance.

Hemostatic abnormalities in uncomplicated babesiosis (Babesia rossi) in dogs.

BACKGROUND: Babesiosis in dogs is associated with severe thrombocytopenia; yet infected dogs rarely show clinical signs of hemorrhage. HYPOTHESIS: Dogs with uncomplicated babesiosis have normal hemostatic capacity despite severe thrombocytopenia. ANIMALS: Nineteen client-owned dogs with uncomplicated babesiosis; 10 healthy controls. METHODS: A prospective, cross-sectional, observational study. Thromboelastography (TEG), prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, D-dimers, and antithrombin (AT) measured in both groups. Statistical significance set at P < .01. RESULTS: Babesiosis group hematocrit and platelet count significantly lower than controls (0.29 versus 0.50 L/L; P < .001 and 20.0 versus 374.5 × 10(9)/L; P < .001, respectively). Except for K, no significant difference in TEG variables between groups. Hemostatic variables for babesiosis group versus controls (mean ± SD); R: 5.9 ± 1.8 versus 4.6 ± 0.9 min (P = .048); K: 2.8 ± 1.1 versus 1.9 ± 0.6 min (P = .003); angle: 55.5 ± 11.7 versus 62.2 ± 4.1 degrees (P = .036); MA: 48.4 ± 9.7 versus 57.2 ± 5.2 mm (P = 0.013); G: 5.1 ± 1.9 versus 6.9 ± 1.5 dyn/cm(2) (P = .019); LY30 (median, range): 0 (0-5.7) versus 0.6% (0-6.1) (P = .152); and LY60: 0 (0-8.8) versus 3.1% (0-13.1) (P = .012). AT activity significantly lower (105.2 ± 16.5 versus 127.8 ± 15.4%; P = .001). Fibrinogen concentration significantly higher in babesiosis group (5.7 ± 1.3 versus. 3.0 ± 0.7 g/L; P < .001). CONCLUSION AND CLINICAL IMPORTANCE: Despite severe thrombocytopenia, dogs with uncomplicated babesiosis did not have clinical signs of hemorrhage and TEG variables were normal, which could indicate a normocoagulable state.

Breed and sex risk factors for canine babesiosis in South Africa.

BACKGROUND: In South Africa, canine babesiosis typically is an acute disease in susceptible individuals and is a major cause of morbidity and mortality. Despite the importance of the disease, there have been no large studies that have examined the influence of breed and sex on disease susceptibility. HYPOTHESIS: Toy breeds have a lower risk of babesiosis than working dogs. ANIMALS: A total of 1,222 dogs diagnosed with canine babesiosis and 11,484 noninfected dogs presented to the Onderstepoort Veterinary Academic Hospital's small animal outpatient clinic between 2004 and 2010. METHODS: Retrospective study. RESULTS: Intact male, neutered male, and neutered female dogs had a significantly higher odds of being diagnosed with canine babesiosis compared to intact female dogs. Five of the 6 Toy breeds had significantly lower odds of being diagnosed with canine babesiosis than did the reference breed, Labrador Retrievers. In contrast, none of the 8 working dog breeds had significantly lower odds compared to the reference breed. CONCLUSIONS AND CLINICAL IMPORTANCE: Intact male, neutered male, and neutered female dogs were at increased risk of canine babesiosis compared to intact female dogs. Several dog breeds, notably Toy breeds, had a lower risk of babesiosis in a hospital population of dogs in South Africa. The mechanism or mechanisms by which Toy breeds are protected from developing canine babesiosis may be related to genetic background or environmental exposure and deserves further study.

Babesiosis as a cause of fever in patients undergoing a splenectomy.

Babesiosis is an emerging infection most commonly acquired from a tick bite. We describe three hospitalized patients with fever attributable to babesiosis after a splenectomy. Splenectomy was done because of splenic enlargement due to unsuspected babesia infection in one patient and because of splenic perforation due to babesiosis in a second patient. The third patient underwent splenectomy for trauma and acquired babesiosis postoperatively from a blood transfusion. Our cases demonstrate the need to be vigilant for babesiosis in patients undergoing splenectomy.