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Acta Veterinaria Scandinavica Jan 2020Abortion is a major source of economic losses in cattle breeding. Abortion occurs due to a wide range of causes, but infections are the most frequently diagnosed....
BACKGROUND
Abortion is a major source of economic losses in cattle breeding. Abortion occurs due to a wide range of causes, but infections are the most frequently diagnosed. However, establishing an aetiological diagnosis remains challenging due to the large variety of bacteria, protozoa, viruses, and fungi that have been associated with abortion in cattle. Economic restraints limit the range of diagnostic methods available for routine diagnostics, and decomposition of the conceptus or lack of proper fetal and/or maternal samples further restrict the diagnostic success. In this study, we report recent diagnostic findings from bovine abortions in Denmark, a country that has a large dairy sector and is free from most infectious agents causing epizootic abortion in cattle. The aims of the study were: (i) to identify infectious causes of bovine abortion in Denmark, (ii) to categorise the diagnostic findings based on the level of diagnostic certainty, and (iii) to assess the diagnostic rate. Due to economic restraints, only a limited panel of routine diagnostic methods were available. Placentas and/or fetuses from mid- to late-term abortions and stillbirths (n = 162) were submitted to the Danish National Veterinary Institute between January 2015 and June 2017. The aborted materials were examined macroscopically, histologically, and by bacterial culture. Maternal blood samples were tested for bovine viral diarrhoea virus (BVDV) antibodies.
RESULTS
The likely aetiology of the abortion was diagnosed in 52 cases, resulting in a diagnostic rate of 33%. The most common cause was protozoal infection (19%) followed by infection with Trueperella pyogenes (3%), Staphylococcus aureus (2%), and non-haemolytic Escherichia coli (2%). Lesions in fetuses with a protozoal infection were consistent with neosporosis. In many cases (38%), inflammatory changes were found in the placenta and/or fetal organs but no specific aetiology was identified. Neither infection with Brucella spp. nor maternal BVDV antibodies were detected. The majority of submitting herds (92%) were each represented by fewer than three abortion cases over the study period.
CONCLUSIONS
Protozoal infection, most likely neosporosis, was the most commonly diagnosed cause of abortion and the only one associated with potential epizootic abortion events. Despite using a reduced number of diagnostic methods in comparison to other abortion studies, the diagnostic rate of this study was within the range reported in an earlier Danish study, as well as in recent international studies. The low number of submitted cases per herd and the sparse anamnestic information provided at submission hampered conclusions on the potential epizootic character of the abortion events in question.
Topics: Abortion, Veterinary; Animals; Antibodies, Viral; Bacterial Infections; Cattle; Cattle Diseases; Denmark; Female; Fetus; Placenta; Pregnancy; Protozoan Infections, Animal
PubMed: 31900210
DOI: 10.1186/s13028-019-0499-4 -
International Journal of Molecular... Apr 2021Leishmaniasis, malaria, toxoplasmosis, and acanthamoebiasis are protozoan parasitic infections. They remain important contributors to the development of kidney disease,... (Review)
Review
Leishmaniasis, malaria, toxoplasmosis, and acanthamoebiasis are protozoan parasitic infections. They remain important contributors to the development of kidney disease, which is associated with increased patients' morbidity and mortality. Kidney injury mechanisms are not fully understood in protozoan parasitic diseases, bringing major difficulties to specific therapeutic interventions. The aim of this review is to present the biochemical and molecular mechanisms in kidneys infected with spp., spp., , and spp. We present available mechanisms of an immune response, oxidative stress, apoptosis process, hypoxia, biomarkers of renal injury in the serum or urine, and the histopathological changes of kidneys infected with the selected parasites. Pathomechanisms of spp. and spp. infections have been deeply investigated, while and spp. infections in the kidneys are not well known yet. Deeper knowledge of kidney involvement in leishmaniasis and malaria by presenting their mechanisms provides insight into how to create novel and effective treatments. Additionally, the presented work shows gaps in the pathophysiology of renal toxoplasmosis and acanthamoebiasis, which need further research.
Topics: Animals; Apoptosis; Humans; Kidney; Leishmaniasis; Malaria; Oxidative Stress; Parasitic Diseases; Protozoan Infections; Toxoplasma; Toxoplasmosis; Transforming Growth Factor beta
PubMed: 33921746
DOI: 10.3390/ijms22084209 -
Veterinary Parasitology Nov 2011Parasitic zoonoses are common and widely distributed in the Southeast Asian region. However, the interactions between parasites, hosts and vectors are influenced by... (Review)
Review
Parasitic zoonoses are common and widely distributed in the Southeast Asian region. However, the interactions between parasites, hosts and vectors are influenced by environmental, socio-cultural and livestock production changes that impact on the distribution, prevalence and severity of disease. In this review we provide an update on new knowledge in the context of ongoing changes for the food-borne pig associated zoonoses Taenia solium and Trichinella spp., the food-borne trematodes Opisthorchis viverrini and Clonorchis sinensis, the water-borne trematodes Schistosoma spp., the vector-borne zoonotic protozoa Plasmodium knowlesi and Leishmania spp. and the soil-borne zoonotic hookworm Ancylostoma ceylanicum. These various changes need to be considered when assessing or developing regional control programs or devising new research initiatives in a changing SE Asia.
Topics: Animals; Asia, Southeastern; Food Parasitology; Helminthiasis; Humans; Protozoan Infections; Soil; Water; Zoonoses
PubMed: 21846580
DOI: 10.1016/j.vetpar.2011.07.013 -
BMJ (Clinical Research Ed.) Aug 2007These diseases could be controlled or eliminated in our lifetimes if efforts are better coordinated
These diseases could be controlled or eliminated in our lifetimes if efforts are better coordinated
Topics: Bacterial Infections; Chronic Disease; Helminthiasis; Humans; Protozoan Infections; Tropical Medicine
PubMed: 17690342
DOI: 10.1136/bmj.39281.645035.80 -
PLoS Neglected Tropical Diseases May 2011In 1995, one of the largest outbreaks of human toxoplasmosis occurred in the Pacific Northwest region of North America. Genetic typing identified a novel Toxoplasma...
In 1995, one of the largest outbreaks of human toxoplasmosis occurred in the Pacific Northwest region of North America. Genetic typing identified a novel Toxoplasma gondii strain linked to the outbreak, in which a wide spectrum of human disease was observed. For this globally-distributed, water-borne zoonosis, strain type is one variable influencing disease, but the inability of strain type to consistently explain variations in disease severity suggests that parasite genotype alone does not determine the outcome of infection. We investigated polyparasitism (infection with multiple parasite species) as a modulator of disease severity by examining the association of concomitant infection of T. gondii and the related parasite Sarcocystis neurona with protozoal disease in wild marine mammals from the Pacific Northwest. These hosts ostensibly serve as sentinels for the detection of terrestrial parasites implicated in water-borne epidemics of humans and wildlife in this endemic region. Marine mammals (151 stranded and 10 healthy individuals) sampled over 6 years were assessed for protozoal infection using multi-locus PCR-DNA sequencing directly from host tissues. Genetic analyses uncovered a high prevalence and diversity of protozoa, with 147/161 (91%) of our sampled population infected. From 2004 to 2009, the relative frequency of S. neurona infections increased dramatically, surpassing that of T. gondii. The majority of T. gondii infections were by genotypes bearing Type I lineage alleles, though strain genotype was not associated with disease severity. Significantly, polyparasitism with S. neurona and T. gondii was common (42%) and was associated with higher mortality and more severe protozoal encephalitis. Our finding of widespread polyparasitism among marine mammals indicates pervasive contamination of waterways by zoonotic agents. Furthermore, the significant association of concomitant infection with mortality and protozoal encephalitis identifies polyparasitism as an important factor contributing to disease severity in marine mammals.
Topics: Animals; Comorbidity; DNA, Protozoan; Genotype; Mammals; Molecular Sequence Data; Multilocus Sequence Typing; North America; Northwestern United States; Prevalence; Sarcocystis; Sarcocystosis; Sequence Analysis, DNA; Severity of Illness Index; Toxoplasma; Toxoplasmosis, Animal
PubMed: 21629726
DOI: 10.1371/journal.pntd.0001142 -
Annals of Parasitology 2017Parasitic diseases of the central nervous system are associated with high mortality and morbidity. Many human parasites, such as Toxoplasma gondii, Entamoeba...
Parasitic diseases of the central nervous system are associated with high mortality and morbidity. Many human parasites, such as Toxoplasma gondii, Entamoeba histolytica, Trypanosoma cruzi, Taenia solium, Echinococcus spp., Toxocara canis, T. cati, Angiostrongylus cantonensis, Trichinella spp., during invasion might involve the CNS. Some parasitic infections of the brain are lethal if left untreated (e.g., cerebral malaria – Plasmodium falciparum, primary amoebic meningoencephalitis (PAM) – Naegleria fowleri, baylisascariosis – Baylisascaris procyonis, African sleeping sickness – African trypanosomes). These diseases have diverse vectors or intermediate hosts, modes of transmission and endemic regions or geographic distributions. The neurological, cognitive, and mental health problems caused by above parasites are noted mostly in low-income countries; however, sporadic cases also occur in non-endemic areas because of an increase in international travel and immunosuppression caused by therapy or HIV infection. The presence of parasites in the CNS may cause a variety of nerve symptoms, depending on the location and extent of the injury; the most common subjective symptoms include headache, dizziness, and root pain while objective symptoms are epileptic seizures, increased intracranial pressure, sensory disturbances, meningeal syndrome, cerebellar ataxia, and core syndromes. Many early symptoms of CNS invasion are often nonspecific therefore a diagnosis can be difficult. This article presents the epidemiology, pathophysiology and clinical manifestations of selected parasitic neuroinfections.
Topics: Antiparasitic Agents; Central Nervous System Parasitic Infections; Helminthiasis; Humans; Protozoan Infections
PubMed: 29385325
DOI: 10.17420/ap6304.111 -
Revue Scientifique Et Technique... Apr 2000Estimates suggest that almost half of the population of the world is affected by water-borne and food-borne infections. Parasitic food-borne and water-borne zoonoses... (Review)
Review
Estimates suggest that almost half of the population of the world is affected by water-borne and food-borne infections. Parasitic food-borne and water-borne zoonoses contribute to this statistic by inflicting a heavy toll on human health and causing serious direct and indirect losses to the agricultural industry. The inability of non-industrialised countries to keep pace with population growth, migration from rural to urban areas and the demand for clean, safe drinking water and proper sanitation means that water-borne zoonoses will continue to exact an increasing burden of ill health in these countries. The consumption of raw or undercooked meat, crustaceans, and fresh-water fish and vegetables facilitates transmission of large numbers of zoonotic infections. The burgeoning tourist industry, emigration and the importation of food from endemic regions has resulted in increasing diagnosis of these infections in non-endemic countries. The authors examine the epidemiology, medical and veterinary public health importance and recent developments in diagnosis, treatment and control of the most important parasitic food-borne and water-borne infections.
Topics: Animals; Food Parasitology; Helminthiasis; Humans; Meat; Protozoan Infections; Seafood; Water; Water Supply; Zoonoses
PubMed: 11189719
DOI: 10.20506/rst.19.1.1218 -
Australian Veterinary Journal May 2022Bovine trichomoniasis, caused by the protozoal parasite Tritrichomonas foetus, is a highly contagious venereal disease characterised by early pregnancy loss, abortion...
Bovine trichomoniasis, caused by the protozoal parasite Tritrichomonas foetus, is a highly contagious venereal disease characterised by early pregnancy loss, abortion and pyometra. Persistently infected bulls and cows are the primary reservoirs of infection in infected herds. This research investigated the prevalence of T. foetus infection in bulls from properties located across northern Australia and New South Wales. Preputial samples were collected from 606 bulls at slaughter and tested for T. foetus using the VetMAX-Gold Trich Detection Kit (Thermo Fisher Scientific). The apparent prevalence of T. foetus infection varied between regions, with northern regions in the Northern Territory, Queensland and Western Australia showing a prevalence of 15.4%, 13.8% and 11.4%, respectively. There was some evidence of an association between infection and postcode (P = 0.06) and increasing bull age (P = 0.054). This study confirms that T. foetus infection is likely to be present in many beef breeding herds and contributing to lower than expected reproductive performance, particularly across northern Australia.
Topics: Abattoirs; Abortion, Veterinary; Animals; Cattle; Cattle Diseases; Female; Male; Northern Territory; Pregnancy; Prevalence; Protozoan Infections, Animal; Tritrichomonas foetus
PubMed: 35080007
DOI: 10.1111/avj.13149 -
Immunological Reviews Jan 2011The neglected tropical diseases (NTDs) represent a group of parasitic and related infectious diseases such as amebiasis, Chagas disease, cysticercosis, echinococcosis,... (Review)
Review
The neglected tropical diseases (NTDs) represent a group of parasitic and related infectious diseases such as amebiasis, Chagas disease, cysticercosis, echinococcosis, hookworm, leishmaniasis, and schistosomiasis. Together, these conditions are considered the most common infections in low- and middle-income countries, where they produce a level of global disability and human suffering equivalent to better known conditions such as human immunodeficiency virus/acquired immunodeficiency syndrome and malaria. Despite their global public health importance, progress on developing vaccines for NTD pathogens has lagged because of some key technical hurdles and the fact that these infections occur almost exclusively in the world's poorest people living below the World Bank poverty line. In the absence of financial incentives for new products, the multinational pharmaceutical companies have not embarked on substantive research and development programs for the neglected tropical disease vaccines. Here, we review the current status of scientific and technical progress in the development of new neglected tropical disease vaccines, highlighting the successes that have been achieved (cysticercosis and echinococcosis) and identifying the challenges and opportunities for development of new vaccines for NTDs. Also highlighted are the contributions being made by non-profit product development partnerships that are working to overcome some of the economic challenges in vaccine manufacture, clinical testing, and global access.
Topics: Animals; Disease Models, Animal; Helminthiasis; Humans; Intestinal Diseases, Parasitic; Neglected Diseases; Parasitic Diseases; Poverty Areas; Protozoan Infections; Protozoan Vaccines; Tropical Medicine; Vaccines
PubMed: 21198676
DOI: 10.1111/j.1600-065X.2010.00976.x -
Cellular and Molecular Life Sciences :... May 2002Recent progress in understanding the neuropathological mechanisms of sleeping sickness reveals a complex relationship between the trypanosome parasite that causes this... (Review)
Review
Recent progress in understanding the neuropathological mechanisms of sleeping sickness reveals a complex relationship between the trypanosome parasite that causes this disease and the host nervous system. The pathology of late-stage sleeping sickness, in which the central nervous system is involved, is complicated and is associated with disturbances in the circadian rhythm of sleep. The blood-brain barrier, which separates circulating blood from the central nervous system, regulates the flow of materials to and from the brain. During the course of disease, the integrity of the blood-brain barrier is compromised. Dysfunction of the nervous system may be exacerbated by factors of trypanosomal origin or by host responses to parasites. Microscopic examination of cerebrospinal fluid remains the best way to confirm late-stage sleeping sickness, but this necessitates a risky lumbar puncture. Most drugs, including many trypanocides, do not cross the blood-brain barrier efficiently. Improved diagnostic and therapeutic approaches are thus urgently required. The latter might benefit from approaches which manipulate the blood-brain barrier to enhance permeability or to limit drug efflux. This review summarizes our current understanding of the neurological aspects of sleeping sickness, and envisages new research into blood-brain barrier models that are necessary to understand the interactions between trypanosomes and drugs active against them within the host nervous system.
Topics: Animals; Antigens, Protozoan; Blood-Brain Barrier; Brain; Central Nervous System Protozoal Infections; Cerebrospinal Fluid; Cytokines; Humans; Nitric Oxide; Prostaglandins; Trypanocidal Agents; Trypanosoma brucei gambiense; Trypanosoma brucei rhodesiense; Trypanosomiasis, African
PubMed: 12088284
DOI: 10.1007/s00018-002-8472-0