Indirect Fluorescent Antibody Test Research Articles

Canonical correlative analyses among an enzyme-linked immunosorbent assay using synthetic peptides, an indirect fluorescent antibody test, and hematologic measurements in dogs infected with Ehrlichia canis.

Immunoreactive tandem repeat proteins (TRPs) in amino acid sequences were identified and employed in the serologic diagnosis of canine monocytic ehrlichiosis (CME). This study evaluated using TRP19 and TRP36 synthetic protein antigens with enzyme-linked immunosorbent assays (ELISAs) and compared the results with an indirect fluorescent antibody test (IFAT) to diagnose CME in the serum of dogs with suspected CME. The sera of 243 dogs that exhibited clinical and hematologic signs suggestive of CME had IFATs performed. An ELISA with synthetic TRP19 and TRP36 antigens from two Ecanis genotypes (USTRP36 and BrTRP36) that circulate in Brazil were also performed. Canonical correlations and chi-square tests were evaluated on the results of these tests. Among the 243 dogs, 179 (73.6%) were reactive at an IFAT≥40, 167 (68.72%) reacted at the cut-off ≥160, and 149 (61.31%) reacted at ≥640. The ELISA revealed that 172 (70.8%) dogs reacted to TRP19 peptide, 163 (67.1%) reacted to USTRP36, and 114 (46.9%) reacted to BrTRP36. The canonical correlation analyses showed that the TRP19 ELISA was the most effective diagnostic method. Serum total protein levels showed strong positive correlations with the USTRP36 peptide. Qualitative analyses revealed an association between the TRP19 peptide and the presence of anemia, thrombocytopenia, and hyperproteinemia. The IFAT results at titers of ≥160 and ≥640 were associated with thrombocytopenia. The results of this study indicated that the TRP19 peptide was an excellent antigen and that the IFAT was diagnostically important in confirming the diagnosis of CME in serum samples.

Microsatellite genotyping reveals extensive genetic diversity in bovine Neospora caninum from the humid Pampa region in Argentina.

Neospora caninum is an apicomplexan protozoan and a major cause of abortion in cattle worldwide. In the Argentinian Humid Pampa, bovine neosporosis causes severe economic losses. Despite this, information on the genetic structure of N. caninum in this region is limited. Therefore, this study aimed to genetically characterize N. caninum isolates associated with bovine abortion in the Humid Pampa region. For this purpose, spontaneous bovine fetal tissues submitted for diagnosis to the Veterinary Diagnostic Service at INTA Balcarce during 2008-2019 were assessed by PCR, indirect fluorescent antibody test (IFAT), and histologic analysis. PCR-positive samples were tested by multilocus microsatellite genotyping (MLGs) using 9 microsatellite markers. Thirty-one different genotypes were identified from 32 samples with at least seven markers. Argentinian MLGs were grouped into two clonal clusters when analyzed using eBURST network and principal coordinate analysis. No segregation based on the year of collection, animal biotype, or geographic origin was observed. In addition, the presence of linkage disequilibrium supported the clonal propagation of Argentinian MLGs. One Argentinian subpopulation was associated with isolates from Spain, Uruguay, Brazil, and Mexico, and the other one was linked to isolates from Scotland, Spain, and Germany. These findings reveal the presence of two clonal subpopulations of N. caninum in the Humid Pampa.

Serosurvey of IgG Antibodies against Bartonella henselae and Rickettsia typhi in the Population of Attica, Greece.

Rickettsia typhi and Bartonella henselae are the causative agents of murine typhus and cat-scratch disease, respectively. A small-scale survey (N = 202) was conducted in the Attica region, Greece, for determining the prevalence rates of IgG antibodies against B. henselae and R. typhi by indirect fluorescence antibody test. IgG against B. henselae and R. typhi were present in 17.8% (36/202) and 4.5% (9/202) of the participants, respectively; co-occurring IgG against both B. henselae and R. typhi were detected in 3.5% (7/202), whereas only anti-B. henselae IgG in 14.3% (29/202), and only anti-R. typhi IgG in 1.0% (2/202). Titres 1/64, 1/128, 1/256, and 1/512, of anti-B. henselae IgG were identified in 6.4%, 4.5%, 4.5%, and 2.4%, whereas titres 1/40 and 1/80 of anti-R. typhi IgG were detected in 4.0%, and 0.5%, respectively. A positive association of anti-B. henselae IgG prevalence with a coastal area featuring a major seaport (p = 0.009) and with younger age (p = 0.046) was identified. The findings of this survey raise concern for exposure of the population of Attica to B. henselae and R. typhi, which should be considered in the differential diagnosis when compatible symptoms are present. Our results also suggest that seaports may represent high-risk areas for exposure to Bartonella spp.

FIRST IMMUNOLOGICAL RECORD OF BABESIA MICROTI HOBET SULINEAGE ANTIBODIES AMONG HUMAN BLOOD DONORS IN QENA GOVERNORATE, UPPER EGYPT, EGYPT

The zoonotic babesiosis is a growing public health concern. This parasite mainly occurs in U.S.(B. microti) and Europe (B. divergens & B. venatorum). Emerging cases have been increasinglyreported worldwide especially in immunosuppressed individuals. Other than tick bite, possiblemodes of infection include perinatal transmission and blood transfusion. To date, in Egypt, threecases of human babesiosis were reported. This study evaluated Babesia spp. infection in man inQena City. Forty three persons were examined. All sera were subjected to serological examinationusing either indirect fluorescent antibody test (IFA) or western blot (WB) analysis or bothtests. Using IFA 13/43 patients were positive for Babesia at different titers. The five out of the13 positive IFAT samples were positive by using WB test (11.6%). This could be the first studyin Qena that screened Egyptian patients using well-defined Babesia strain for human babesiosis.Blood transfusion is a possible babesiosis mode of infection to man and thus patients in need ofblood transfusion may undergo immunosuppressive status so they may develop babesiosis, soscreening of blood donors for human babesiosis is needed to exclude transfusion inducedbabesiosis.

FIRST IMMUNOLOGICAL RECORD OF BABESIA MICROTI HOBET SULINEAGE ANTIBODIES AMONG HUMAN BLOOD DONORS IN QENA GOVERNORATE, UPPER EGYPT, EGYPT

The zoonotic babesiosis is a growing public health concern. This parasite mainly occurs in U.S.(B. microti) and Europe (B. divergens & B. venatorum). Emerging cases have been increasinglyreported worldwide especially in immunosuppressed individuals. Other than tick bite, possiblemodes of infection include perinatal transmission and blood transfusion. To date, in Egypt, threecases of human babesiosis were reported. This study evaluated Babesia spp. infection in man inQena City. Forty three persons were examined. All sera were subjected to serological examinationusing either indirect fluorescent antibody test (IFA) or western blot (WB) analysis or bothtests. Using IFA 13/43 patients were positive for Babesia at different titers. The five out of the13 positive IFAT samples were positive by using WB test (11.6%). This could be the first studyin Qena that screened Egyptian patients using well-defined Babesia strain for human babesiosis.Blood transfusion is a possible babesiosis mode of infection to man and thus patients in need ofblood transfusion may undergo immunosuppressive status so they may develop babesiosis, soscreening of blood donors for human babesiosis is needed to exclude transfusion inducedbabesiosis.

Prevalence and Risk Factors of East Coast Fever in the Copperbelt and Central Provinces of Zambia

East Coast fever (ECF) is an infectious tick-borne disease of cattle, caused by a protozoan parasite Theileria parva. It is a disease of major economic importance in Zambia as it is the main cause of cattle morbidity and mortality. Despite its economic importance, the epidemiology of ECF in Zambia is poorly understood, thereby making ECF prevention and control difficult. Further, there is limited published literature on this disease in Zambia, with little available research concentrating on Southern and Eastern provinces. Such literature is mostly based on serological techniques such as indirect fluorescent antibody test (IFAT) which have limited sensitivity and specificity. Thus, this study was conducted to determine the prevalence and associated risk factors of ECF in Copperbelt and Central provinces of Zambia. The study was cross-sectional in design. Multistage cluster sampling was used involving district, veterinary camp, herd and individual animals. The provinces and districts were selected based on their vast potential for livestock production and the previously reported incidence of ECF. From each district, two veterinary camps were randomly selected. From each camp, herds were randomly selected from which individual animals were randomly sampled. Samples were collected from Mpongwe and Masaiti districts (Copperbelt province) and Kapiri Mposhi and Chibombo districts (Central province). Samples were examined for the presence of schizonts on Giemsa stained lymph smears. The lymph smear examinations revealed that 6.4% (95%, CI=4.9-7.9) of the samples were positive for T. parva schizonts. In Central province, the overall prevalence was 6.7% (95%, CI=4.0-8.2), while in the Copperbelt province it was 6.1% (95%, CI=4.0-8.2). Among the districts in these provinces, Kapiri Mposhi did not record any schizont positive cattle, while Masaiti recorded 2.4% (95%, CI=0.5-4.3). Mpongwe had a prevalence of 9.7% (95%, CI=6.0-13.4) and Chibombo had the highest prevalence at 13.6% (95%, CI=9.4-17.9). Risk factors that were identified to be associated with ECF were the district, frequency of veterinary service provision, tick control frequency, age and previous experience of ECF. The results indicate that ECF is prevalent in Copperbelt and Central provinces and hindering livestock production. There is hence the need for concerted efforts to control ticks and prevent ECF transmission through farmer sensitization, routine, regular, mandatory and supervised dipping and spraying of cattle and stringent livestock movement control.

RISK OF TOXOPLASMOSIS FROM CATS

Toxoplasmosis is a zoonotic disease caused by Toxoplasma gondii, there are two hosts , cats play an important role as definitive hosts , cattle, sheep ,goats and human may play as intermediate hosts. Humans be infected by eating tissue cysts from Not cooked flesh and eat contaminated feed or water with oocytes shed in the faecal of infected cats. diagnosis of T. gondii itself is affirmation the infection but difficult, so many laboratories use serological methods to detect immunoglobulins which specific to T. gondii : latex agglutination (LA) test, Enzyme Linked Immuno Sorbent Assay and indirect fluorescent antibody test (IFAT) those methods was differ in specificity and sensitivity there is no systematic review that can perform the state of toxoplasmosis in the definitive host. Therefore the aims of the current existing review was to decided the risk factor of T. gondii infection and demonstrated the epidemiological form of infection in cats in Iraq.

Urological detection of specific antibodies against Neospora caninum infection in mice: A prospect for novel diagnostic approach of Neospora

The intracellular protozoan parasite Neospora caninum is incriminated to induce drastic economic losses in both livestock and pet animal industries. Neosporosis is primarily characterized by abortion in cattle and paralytic symptoms in dogs. Because there are no effective treatments or vaccines, diagnosis is critical for Neospora control. Thus, diversification of laboratory tests and specimens used for diagnosis of N. caninum is an essential scientific endeavor to judge and select the most appropriate diagnostic tool. Herein, we provide the first evidence for the utility of urine samples for demonstration of specific antibodies against N. caninum employing an experimentally infected murine model. Specific antibodies to recombinant N. caninum dense granule 7, surface antigen 1, and lysate antigen were assayed using different antibodies-based ELISAs. Urine based IgG ELISA efficiently discriminated between infected mice (acute or chronic infection), and those of non-infected mice. This effect was also noticed for IgG1 and IgG2a suggesting the utility of urine for assessment of T-helper 2- and T-helper 1-mediated immunities, respectively. In addition, reactivity of specific antibody in urine was also confirmed against parasites when indirect fluorescent antibody test was employed. Usefulness of urine as an additional clinical sample for Neospora diagnosis was confirmed via comparison with the relevant control non-infected and infected mouse sera as reference samples. Because of minimum invasiveness and ease of urine collection, this approach might offer new diagnostic opportunities for N. caninum either for the field or research purposes. However, further studies are required to extrapolate this preliminary study and results in the animal species of interest particularly in dogs.

Dynamics of anti-malarial antibodies in non-immune patients during and after a first and unique Plasmodium falciparum malaria episode

BackgroundMalaria is a major travel medicine issue. Retrospective confirmation of a malaria episode diagnosed in an endemic area can have relevant implications in transfusional medicine in Europe, where blood donors are excluded from donation on the basis of positive malaria serology. However, there is scarce evidence on the dynamics of anti-malarial antibodies after a first malaria episode in non-immune individuals. The first aim of this study was to describe the dynamics of anti-malarial antibodies in a first malaria episode in non-immune travellers. Secondary objectives were to assess the sensitivity of serology for a retrospective diagnosis in non-immune travellers diagnosed while abroad and to discuss the implications in transfusional medicine.MethodsRetrospective analysis of the results of an indirect fluorescence antibody test (IFAT) for malaria available for patients with a first malaria episode by Plasmodium falciparum and admitted at the IRCCS Sacro Cuore Don Calabria hospital in a 14-year period. The antibody titres were collected at baseline and during further follow up visits. Epidemiological, demographic and laboratory test results (including full blood count and malaria parasite density) were anonymously recorded in a study specific electronic Case Report Form created with OpenClinica software. Statistical analysis was performed with SAS software version 9.4.ResultsThirty-six patients were included. Among them, all but two were Europeans (one African and one American). Median length of fever before diagnosis was 2 days (IQR 1–3). Thirty-five patients had seroconversion between day 1 and day 4 from admission, and the titre showed a sharply rising titre, often to a very high level in a few days. Only a single patient remained negative in the first 5 days from admission, after which he was no more tested. Six patients were followed up for at least 2 months, and they all showed a decline in IFAT titre, tending to seroreversion (confirmed in one patient with the longest follow up, almost 4 years).ConclusionsSerology demonstrated reliable for retrospective diagnosis in non-immune travellers. The decline in the anti-malarial titre might be included in the screening algorithms of blood donors, but further studies are needed.

Serological Survey of Neospora caninum and Toxoplasma gondii Co-Infection in Rodents in Northwestern Iran

Our knowledge of the epidemiology of rodents' parasitic agents in Iran is scarce, although some of these pathogens play an important role in human and veterinary medicine, such as Toxoplasma gondii and Neospora caninum. The purpose of this study was to determine the seroprevalence of Toxoplasma gondii and Neospora caninum in rodents of northwestern Iran between Mar and Dec 2015. Overall, 157 serum samples from rodents (101 Meriones persicus, 41 Mus musculus, and 15 Cricetulus migratorius) were assayed by the indirect fluorescence antibody test (IFAT) for antibodies to T. gondii and N. caninum. We found a prevalence of 20.38% (32/157) for N. caninum, 35% (55/157) for T. gondii. Co-presence of antibodies to N. caninum and T. gondii was found in 10 (6.36%) rodents. A significant association was found between the rodents species and seropositivity to N. caninum (P<0.05) but there was no association with rodents species for T. gondii. The overall prevalence of the aforementioned parasites was higher in male versus female rodents. The high seroprevalence of toxoplasmosis and neosporosis in rodents in the study area has implications for translocation of these infections across wider geographical regions since these rodents are mostly preyed on by cats or dogs; hence, which can transfer the parasite to other hosts.

First record of besnoitiosis caused by Besnoitia bennetti in donkeys from the UK

BackgroundThe involvement of Besnoitia bennetti in skin pathologies was investigated in a series of 20 donkeys from the Donkey Sanctuary in England, in the 2013–2019 period.MethodsThe initial histopathological finding of Besnoitia cysts in skin lumps that were presumed to be sarcoids in 2013 triggered our cognisance of this parasite and resulted in identification of a total of 20 cases. Histopathological examination of surgical biopsy samples collected from 8 live donkeys and tissue specimens from 12 deceased donkeys at post-mortem examination revealed the presence of Besnoitia cysts in all 20 donkeys. The indirect fluorescent antibody test (IFAT) and immunoblotting analysis showed the presence of anti-Besnoitia antibodies in archived serum samples from 4 deceased donkeys. Additionally, infection was evidenced in one live donkey based on IFAT and immunoblot analysis of tissue fluid of a dermal mass containing Besnoitia cysts, and real-time (RT)-PCR analysis and microsatellite genotyping of DNA isolated from the tissue of the same dermal mass confirmed the infection specifically as B. bennetti.ResultsBoth serological and microsatellite analyses confirmed the aetiology to be B. bennetti. Our findings suggested that in cases of skin masses such as sarcoids, the suspicion of B. bennetti infection should be borne in mind even when clinical and histopathology examination results are negative in order to avoid misdiagnosis.ConclusionsThis case series documents, to our knowledge, the first report of B. bennetti infection in donkeys in the UK, indicating that donkey besnoitiosis has become noteworthy in the UK. Further investigations of the occurrence, epidemiological characteristics, and clinical manifestations of B. bennetti infection in donkeys and other equids are warranted.

Serological and molecular detection of Neospora caninum and Toxoplasma gondii in human umbilical cord blood and placental tissue samples

Neosporosis primarily affects cattle and dogs and is not currently considered a zoonotic disease. Toxoplasmosis is a zoonosis with a worldwide distribution that is asymptomatic in most cases, but when acquired during pregnancy, it can have serious consequences. The seropositivity rates determined by the indirect fluorescent antibody test for Neospora caninum (N. caninum) and Toxoplasma gondii (T. gondii) were 24.3% (49 samples) and 26.8% (54 samples), respectively. PCR positivity for N. caninum was observed in two samples of cord blood (1%) using the Nc5 and ITS1 gene, positivity for T. gondii was observed in 16 samples using the primer for the B1 gene (5.5% positivity in cord blood and 2.5% positivity in placental tissue). None of the samples showed structures characteristic of tissue cysts or inflammatory infiltrate on histopathology. Significant associations were observed only between N. caninum seropositivity and the presence of domestic animals (p = 0.039) and presence of dogs (p = 0.038) and between T. gondii seropositivity and basic sanitation (p = 0.04). This study obtained important findings regarding the seroprevalence and molecular detection of N. caninum and T. gondii in pregnant women; however, more studies are necessary to establish a correlation between risk factors and infection.

Molecular and Serological Study of Neospora caninum Infection among Dogs and Foxes in Sanandaj, Kurdistan Province, Iran.

Neospora caninum, a protozoan parasite, causes abortions in cattle, as well as neurological disorders and reproductive problems in dogs. This study aimed to investigate the serological and the molecular prevalence of N.caninum among foxes and dogs using indirect fluorescent antibody test (IFAT) and nested-polymerase chain reaction (PCR). For this purpose, 288 and 95 both fecal and serum samples of dogs and foxes were collected, respectively, from around industrial and traditional dairy flocks in different parts of Sanandaj, Kurdistan Province, Iran, from 2013 to 2015. The sera were examined using IFAT, and fecal samples were microscopically assessed for detecting Neospora oocyst and by nested-PCR. The findings revealed that N.caninum seroprevalence were 4.86% and 4.21% in dogs and foxes, respectively. In addition, no Neospora oocysts were found microscopically and by PCR. Since this study is the first serological and molecular investigation of N.caninum among both dogs and foxes in Sanandaj, the findings of indicated that stray dogs is a main source of N.caninum infection in dairy farms in Sanandaj, Iran.

Spatial serosurvey of anti-Toxoplasma gondii antibodies in individuals with animal hoarding disorder and their dogs in Southern Brazil

Despite vulnerability and unsanitary conditions of animal hoarding may predispose environmental contamination and spread of vectors and pathogens, no study to date has focused on their impact on public health and zoonotic diseases. Accordingly, this study aimed to assess the seroprevalence of anti-Toxoplasma gondii antibodies and associated factors in individuals with animal hoarding disorder (AHD) and their dogs in Curitiba, Southern Brazil. Blood samples were obtained from 264 dogs (21 households) and 19 individuals with AHD (11 households). Their blood was tested by indirect fluorescent antibody test (IFAT). Overall, anti-Toxoplasma gondii seropositivity was found in 21/264 dogs (7.95%; 95% CI: 4.69–11.22) with titers ranging from 16 to 4096, and in 7/19 individuals with AHD (36.84%; CI: 15.15–58.53) with titers ranging from 16 to 64. Serological analysis for anti-T. gondii antibodies were considered positive in at least one individual or dog in 9/11 (81.82%; 95% CI: 59.03–100.00) cases that were thoroughly assessed. Surprisingly, the seropositivity of individuals with AHD and their dogs was among the lowest reportedly observed in human and dog populations of Brazil. There was no significant association between positive owners and positive dogs or the presence of cats in the household. Regard epidemiological variables, a significant association was found between dog’s seropositivity and the type of dog food. To the authors’ knowledge, the present study represents the first investigation of T. gondii seroprevalence in individuals with hoarding disorder and their dogs. In conclusion, despite low sanitary conditions, anti-Toxoplasma gondii antibodies frequency in individuals with AHD and their dogs are lower than the general population likely due to low protozoan load in such isolated households.

New record of preclinical diagnosis of American visceral leishmaniasis in Amazonian Brazil encourages optimizing disease control

The clinical-immunological spectrum of human Leishmania (L.) infantum chagasi-infection in Amazonian Brazil has recently been reviewed based on the combined use of the delayed-type hypersensitivity (DTH) and indirect fluorescence antibody test (IFAT-IgG/IgM), both with homologous L. (L.) infantum chagasi-antigens, and associated with the clinical evaluation of infected individuals. This diagnostic approach has allowed to identify the broadest clinical-immunological spectrum of human L. (L.) infantum chagasi-infection composed by five clinical-immunological profiles of infection: three asymptomatic, 1) Asymptomatic Infection (AI) [DTH+/++++, IFAT−], 2) Subclinical Resistant Infection (SRI) [DTH+/++++, IFAT+/++], and 3) Indeterminate Initial Infection (III) [DTH−, IFAT+/++], and two symptomatic ones, 4) Symptomatic Infection (SI) [=American visceral leishmaniasis - AVL] and, 5) Subclinical Oligosymptomatic Infection (SOI), both with the same immune profile [DTH−, IFAT+++/++++]. Herein, we confirm for the third time the preclinical diagnosis of AVL through IgM-antibody response in an early asymptomatic case of infection (profile III), a 17-year-old boy who evolved to AVL (=profile SI) six weeks after the initial infection diagnosis, confirming that the combined use of DTH and IFAT-(IgG/IgM) assays associated with the clinical evaluation of infected individuals is potentially useful for monitoring human L. (L.) infantum chagasi-infection in endemic areas as well as optimizing AVL control.

Seroprevalence of Selected Tick Borne Pathogens and Diversity and Abundance of Ixodid Ticks (Acari: Ixodidae) at the Wildlife-Livestock Interface in Northern Botswana.

Ticks and tick borne diseases (TBDs) undermine livestock production with considerable economic losses to livestock producers in endemic areas worldwide. Despite the impact of ticks and TBDs in livestock production, there is a paucity of information on ticks and diseases they transmit in Botswana. To address this gap, a cross-sectional study was conducted to determine (i) the seroprevalence of selected tick borne (TB) pathogens and (ii) the diversity and abundance of ixodid ticks among 301 cattle foraging around two protected areas in northern Botswana, differing by the presence or absence of a physical barrier (fence) separating wildlife and livestock. Competitive inhibition enzyme linked immuno-sorbent assay (cELISA) was used to test for Anaplasma spp. infection and Indirect Fluorescence Antibody Test (IFAT) was used to test for Theileria parva, Babesia bovis, and B. bigemina. Ticks were identified morphologically at either genus or species level. Seroprevalence of cattle was found to be 90% for Anaplasma spp., followed by 38.6% for Babesia spp. and 2.4% for T. parva. Except for Babesia spp., comparisons of the seroprevalence of the selected haemoparasites between the two wildlife-livestock interface areas were not significantly different. The overall prevalence of ticks was found to be 73.4% with Amblyomma variegatum being the most abundant (53.1%) followed by Rhipicephalus evertsi evertsi (31.7%) and R. (B.) decoloratus (7.7%). Except for Babesia spp., comparisons of the seroprevalence of the selected haemoparasites between the two study areas were not significantly different while comparisons of the burden of tick infestation between the study sites revealed significant difference for A. variegatum and R. evertsi evertsi with both tick infestations higher where there is no barrier. Our work provided baseline data on TBD pathogens and tick infestation in cattle populations exposed to different levels of contact with adjacent buffalo populations. The presence of a veterinary fence did not significantly influence the seroprevalence of the selected TBD pathogens (except for Babesia spp.) but seemed to reduce tick burdens in cattle. Findings from this study can be used for guiding future epidemiological study designs to improve our understanding of ticks and TBDs dynamics in northern Botswana.

Longitudinal study of Toxoplasma gondii antibodies in female lambs from Paraíba State, Brazil

Toxoplasmosis is a worldwide zoonosis that affects man and homeothermic animals, caused by the protozoan Toxoplasma gondii. This parasite is responsible for congenital diseases, miscarriage and stillbirth in some species, such as sheep. Although outbreaks of abortion are considered important, descriptions of these outbreaks in ewes in Brazil are rare, even though infection is highly prevalent, and isolates are very virulent. Studies have shown a strong association between the presence of antibodies against the parasite in mothers and a low occurrence of reproductive problems by T. gondii during pregnancy. The objective of the study was to evaluate the occurrence of T. gondii infection in sheep from the semi-arid region of Paraíba State, Brazil, and to determine if these animals acquire the infection in the first year of life, before the beginning of the reproductive phase. This was done by monitoring the dynamics of anti-T. gondii antibodies by indirect fluorescence antibody test (IFAT ≥ 64) in animal serum from birth to 12 months of age, obtained once a month. Fifty-six crossbreed females and their 61 offspring, belonging to seven semi-intensive farms (representative of the region's farms) were evaluated. Of the 61 lambs studied, 55.7% (34/61) (IC 95% 44.9%-71.4%) were antibody negative at the end of 12 months, as only presumed colostrum antibodies were detected in these animals or they remained negative throughout the study. The remaining 44.3% (27/61) (IC 95% 28.6%-55.1%) were either presenting high antibody titres since the first examination (5/27; 18.5%), or became seropositive in the first year of life (22/27; 81.5%). Antibody titres ranged from 64 to 65,356 and the variables analysed (presence of cats, type of water supplied, type of flock, sanitary management and existence of sewage within the property) were not associated with the seroconversion of the lambs. The study concludes that about half of the ewes were seronegative at the age of one year, the time of their first gestation and, probably, they are more susceptible to reproductive problems caused by this coccidia.

Role of asymptomatic and symptomatic humans as reservoirs of visceral leishmaniasis in a Mediterranean context.

BackgroundIn the Mediterranean basin, Leishmania infantum is the causative agent of visceral leishmaniasis (VL), a zoonosis in which the dog is the primary domestic reservoir, although wildlife may have a leading role in the sylvatic cycle of the disease in some areas. Infections without disease are very frequent. There is limited information regarding the role that VL patients and asymptomatic infected individuals could be playing in the transmission of L. infantum. Xenodiagnosis of leishmaniasis has been used in this descriptive study to explore the role of symptomatic and asymptomatic infected individuals as reservoirs in a recent focus of leishmaniasis in southwestern Madrid, Spain.Methodology and main findingsAsymptomatic blood donors (n = 24), immunocompetent patients who were untreated (n = 12) or treated (n = 11) for visceral leishmaniasis (VL), and immunocompromised patients with VL (n = 3) were enrolled in the study. Their infectivity to Phlebotomus perniciosus was studied by indirect xenodiagnosis on peripheral blood samples. Quantitative polymerase chain reaction of blood samples from immunocompetent patients untreated for VL and immunocompromised untreated, treated and under secondary prophylaxis for VL was performed. Antibodies against Leishmania were studied by indirect fluorescent antibody and rK39-immunochromatographic tests. A lymphoproliferative assay with a soluble Leishmania antigen was used to screen for leishmaniasis infection in the healthy population. Sixty-two xenodiagnostic tests were carried out and 5,080 sand flies were dissected. Positive xenodiagnosis was recorded in four patients, with different sand fly infection rates: 1 immunosuppressed HIV / L. infantum coinfected asymptomatic patient, 1 immunosuppressed patient with multiple myeloma and symptomatic active VL, and 2 immunocompetent patients with untreated active VL. All blood donors were negative for both xenodiagnosis and conventional PCR.Conclusions / SignificanceThere is no consensus amongst authors on the definition of an ‘asymptomatic case’ nor on the tools for screening; we, therefore, have adopted one for the sake of clarity. Immunocompetent subjects, both infected asymptomatics and those treated for VL, are limited in number and appear to have no epidemiological relevance. The impact is limited for immunocompetent patients with untreated active VL, whilst immunosuppressed individuals undergoing immunosuppressive therapy and immunosuppressed individuals HIV / L. infantum coinfected were the most infectious towards sand flies. It is noteworthy that the HIV / L. infantum coinfected patient with asymptomatic leishmaniasis was easily infectious to sand flies for a long time, despite being under continuous prophylaxis for leishmaniasis. Accordingly, screening for latent Leishmania infection in HIV-infected patients is recommended in scenarios where transmission occurs. In addition, screening for VL in HIV-infected patients who have spent time in VL-endemic areas should also be implemented in non-endemic areas. More research is needed to better understand if some asymptomatic coinfected individuals contribute to transmission as ‘super-spreaders’.

Prevalence of ticks (Acari: Ixodidae) and Theileria annulata infection of cattle in Gezira State, Sudan

This study was conducted in Gezira State, central Sudan during January, May and August 2014 to determine species of ticks infesting cattle and prevalence of Theileria annulata infection and antibodies. A total of 200 head of cattle were sampled for ticks, blood smears, lymph node biopsy smears and sera from five study areas. Zebu (Butana and Kenana) and cross-bred (Zebu X Friesian) cattle of both sexes were sampled. Cattle age groups were younger than one year, one year to younger than four years and four years and older. Coat colour of cattle was recorded. The results revealed that cattle were infested with Rhipicephalus evertsi evertsi (n = 562, 51.6%), Hyalomma anatolicum (n = 289, 26.5%), H. rufipes (n = 70, 6.4%), R. sanguineus sanguineus (n = 59, 5.4%), R. decoloratus (n = 39, 3.6%), Amblyomma lepidum (n = 35, 3.2%), H. impeltatum (n = 26, 2.4%) and H. dromedarii (n = 9, 0.8%). Out of 200 blood and biopsy smears, 33 (16.5%) showed piroplasms for Theileria spp., while 29 (14.5%) were positive for Theileria spp. schizonts. Seropositivity for T. annulata using indirect fluorescent antibody (IFA) test was 94 (47%). It is concluded that there are three genera of hard ticks and eight species in Gezira State and tropical theileriosis is endemic in the state. These findings are the first records in Gezira State, Central Sudan and it is highly recommended to consider the endemicity of tropical theileriosis particularly in cattle upgrading programmes.

A case of Henoch-Sch\xf6nlein purpura associated with scrub typhus

BackgroundHenoch-Schönlein purpura (HSP) may be caused by several allergens. However, to date, HSP caused by Orientia tsutsugamushi has not been reported. Here, we report an unusual rash with features of HSP caused by Orientia tsutsugamushi.Case presentationA man visited a tertiary hospital with bilateral symmetrical purpura and fever. He presented with an eschar in the left popliteal fossa and proteinuria. He was diagnosed with tsutsugamushi disease by indirect fluorescent antibody and positive polymerase chain reaction tests. Purpura biopsy demonstrated a feature of leukocytoclastic vasculitis and IgA deposition in dermal vessels, indicative of HSP.ConclusionsWhen examining patients with unique rashes, such as in this case, we suggest investigating out-door activities and evidence of mite bites. Furthermore, differential diagnosis of tsutsugamushi disease should be considered when necessary.