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Henke K, Ntovas S, Xourgia E, Exadaktylos AK, Klukowska-Rötzler J, Ziaka M. Who Let the Dogs Out? Unmasking the Neglected: A Semi-Systematic Review on the Enduring Impact of Toxocariasis, a Prevalent Zoonotic Infection. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:6972. [PMID: 37947530 PMCID: PMC10649795 DOI: 10.3390/ijerph20216972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 09/28/2023] [Accepted: 10/17/2023] [Indexed: 11/12/2023]
Abstract
Toxocariasis remains an important neglected parasitic infection representing one of the most common zoonotic infections caused by the parasite Toxocara canis or, less frequently, by Toxocara cati. The epidemiology of the disease is complex due to its transmission route by accidental ingestion of embryonated Toxocara eggs or larvae from tissues from domestic or wild paratenic hosts. Even though the World Health Organization and Centers for Disease Control classified toxocariasis amongst the top six parasitic infections of priority to public health, global epidemiological data regarding the relationship between seropositivity and toxocariasis is limited. Although the vast majority of the infected individuals remain asymptomatic or experience a mild disease, the infection is associated with important health and socioeconomic consequences, particularly in underprivileged, tropical, and subtropical areas. Toxocariasis is a disease with multiple clinical presentations, which are classified into five distinct forms: the classical visceral larva migrans, ocular toxocariasis, common toxocariasis, covert toxocariasis, and cerebral toxocariasis or neurotoxocariasis. Anthelmintic agents, for example, albendazole or mebendazole, are the recommended treatment, whereas a combination with topical or systemic corticosteroids for specific forms is suggested. Prevention strategies include educational programs, behavioral and hygienic changes, enhancement of the role of veterinarians, and anthelmintic regimens to control active infections.
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Affiliation(s)
- Katrin Henke
- Department of Internal Medicine, Thun Hospital, Krankenhausstrasse 12, 3600 Thun, Switzerland;
- Department of Emergency Medicine, Inselspital, University Hospital, University of Bern, 3008 Bern, Switzerland; (S.N.); (A.K.E.); (J.K.-R.)
| | - Sotirios Ntovas
- Department of Emergency Medicine, Inselspital, University Hospital, University of Bern, 3008 Bern, Switzerland; (S.N.); (A.K.E.); (J.K.-R.)
- Department of Visceral Surgery and Medicine, lnselspital, University Hospital, University of Bern, 3008 Bern, Switzerland
| | - Eleni Xourgia
- Department of Heart Surgery, lnselspital, University Hospital, University of Bern, 3008 Bern, Switzerland;
| | - Aristomenis K. Exadaktylos
- Department of Emergency Medicine, Inselspital, University Hospital, University of Bern, 3008 Bern, Switzerland; (S.N.); (A.K.E.); (J.K.-R.)
| | - Jolanta Klukowska-Rötzler
- Department of Emergency Medicine, Inselspital, University Hospital, University of Bern, 3008 Bern, Switzerland; (S.N.); (A.K.E.); (J.K.-R.)
| | - Mairi Ziaka
- Department of Internal Medicine, Thun Hospital, Krankenhausstrasse 12, 3600 Thun, Switzerland;
- Department of Emergency Medicine, Inselspital, University Hospital, University of Bern, 3008 Bern, Switzerland; (S.N.); (A.K.E.); (J.K.-R.)
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Kaneva E, Rainova I, Harizanov R, Kaftandjiev I. "Study of IgG avidity and the level of specific IgA antibodies and their significance in the diagnosis of human toxocarosis". Exp Parasitol 2022; 236-237:108236. [PMID: 35247381 DOI: 10.1016/j.exppara.2022.108236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 01/20/2022] [Accepted: 03/01/2022] [Indexed: 11/04/2022]
Abstract
Toxocarosis is a zoonotic disease caused by migration and subsequent localization of nematode larvae of Toxocara spp. in human organs and tissues, which is manifested with development of various non-specific clinical symptoms. Main diagnostic methods are serological and consists in proving the presence of anti-Toxocara IgG antibodies in patient's sera. In humans, anti-Toxocara IgG has been shown to persist in the serum for a long time and cannot be used to distinguish between past and recent infection. Aim of the present work is to investigate the diagnostic significance of the specific IgG avidity level, determined by an immuno enzyme test developed by us, and the presence of anti-Toxocara IgA for distinguishing between acute and chronic toxocarosis. The study included 130 patients with positive results in routine serological ELISA and Western blot tests and with clinical symptoms of visceral and ocular toxocarosis. The results revealed low IgG avidity (≤40%) in nine (7.3%) and presence of anti-Toxocara IgA antibodies in 36 (26.2%) of the subjects. Low avidity of IgG antibodies was found only in the first tests, and a presence of specific IgA for up to 9 months. The results of our study give us reason to believe that determination of the IgG avidity in toxocarosis is of greater diagnostic value than the presence of IgA to establish the stage of the disease.
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Affiliation(s)
- Eleonora Kaneva
- National Centre of Infectious and Parasitic Diseases, Sofia, Bulgaria; Department of Parasitology and Tropical Medicine, 1504, Sofia, 26, Yanko Sakazov Blvd, Bulgaria.
| | - Iskra Rainova
- National Centre of Infectious and Parasitic Diseases, Sofia, Bulgaria; Department of Parasitology and Tropical Medicine, 1504, Sofia, 26, Yanko Sakazov Blvd, Bulgaria.
| | - Rumen Harizanov
- National Centre of Infectious and Parasitic Diseases, Sofia, Bulgaria; Department of Parasitology and Tropical Medicine, 1504, Sofia, 26, Yanko Sakazov Blvd, Bulgaria.
| | - Iskren Kaftandjiev
- National Centre of Infectious and Parasitic Diseases, Sofia, Bulgaria; Department of Parasitology and Tropical Medicine, 1504, Sofia, 26, Yanko Sakazov Blvd, Bulgaria.
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Inácio SV, Gomes JF, Falcão AX, Martins dos Santos B, Soares FA, Nery Loiola SH, Rosa SL, Nagase Suzuki CT, Bresciani KDS. Automated Diagnostics: Advances in the Diagnosis of Intestinal Parasitic Infections in Humans and Animals. Front Vet Sci 2021; 8:715406. [PMID: 34888371 PMCID: PMC8650151 DOI: 10.3389/fvets.2021.715406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 10/19/2021] [Indexed: 11/25/2022] Open
Abstract
The increasingly close proximity between people and animals is of great concern for public health, given the risk of exposure to infectious diseases transmitted through animals, which are carriers of more than 60 zoonotic agents. These diseases, which are included in the list of Neglected Tropical Diseases, cause losses in countries with tropical and subtropical climates, and in regions with temperate climates. Indeed, they affect more than a billion people around the world, a large proportion of which are infected by one or more parasitic helminths, causing annual losses of billions of dollars. Several studies are being conducted in search for differentiated, more sensitive diagnostics with fewer errors. These studies, which involve the automated examination of intestinal parasites, still face challenges that must be overcome in order to ensure the proper identification of parasites. This includes a protocol that allows for elimination of most of the debris in samples, satisfactory staining of parasite structures, and a robust image database. Our objective here is therefore to offer a critical description of the techniques currently in use for the automated diagnosis of intestinal parasites in fecal samples, as well as advances in these techniques.
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Affiliation(s)
- Sandra Valéria Inácio
- São Paulo State University (Unesp), School of Veterinary Medicine, Araçatuba, Brazil
| | - Jancarlo Ferreira Gomes
- School of Medical Sciences, University of Campinas (UNICAMP), Campinas, Brazil
- Institute of Computing (IC), University of Campinas (UNICAMP), Campinas, Brazil
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Menu E, Kopec L, Luciani L, Legrand S, L’Ollivier C. Measurement of the IgG Avidity Index in the Diagnosis of Clinical Toxocariasis Patients. Pathogens 2021; 10:pathogens10091086. [PMID: 34578119 PMCID: PMC8468318 DOI: 10.3390/pathogens10091086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/23/2021] [Accepted: 08/24/2021] [Indexed: 12/01/2022] Open
Abstract
Toxocara spp. are parasitic nematodes responsible for human toxocariasis, a common zoonotic helminth infection. The five main features of human toxocariasis are the classical ocular toxocariasis and visceral larva migrans syndrome, followed by covert toxocariasis, common toxocariasis and neurotoxocariasis. The diagnosis of toxocariasis is feasible by considering clinical symptoms, anamnestic history and serology laboratory results; however, serological criteria cannot be used to distinguish active Toxocara infection from past exposure, which is an area of much discussion in clinical practice. In this context, we developed avidity tests (ELISA and immunoblotting) and evaluated their clinical usefulness in distinguishing past from active toxocariasis. Our study involved 46 patients divided into two groups: “active toxocariasis” (n = 14) and “chronic toxocariasis” (n = 32). According to the avidity indices obtained for both the chronic and active toxocariasis groups, we proposed two thresholds: first, an AI lower than 32% supports an active infection; secondly, a threshold above 42% can exclude an active infection. In order to use this assay in routine clinical practice, however, is still requires standardisation with regards to the method and threshold values, which can be established through studies involving larger populations.
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Affiliation(s)
- Estelle Menu
- Laboratoire de Parasitologie-Mycologie, Institut Hospitalo-Universitaire Méditerranée Infection, 13385 Marseille, France; (E.M.); (L.K.); (S.L.)
- VITROME: Vecteurs-Infections Tropicales et Méditerranéennes, Service de Santé des Armées, Assistance Publique-Hôpitaux de Marseille, Institut de Recherche pour le Développement, Aix Marseille Université, 13385 Marseille, France
| | - Lora Kopec
- Laboratoire de Parasitologie-Mycologie, Institut Hospitalo-Universitaire Méditerranée Infection, 13385 Marseille, France; (E.M.); (L.K.); (S.L.)
| | - Léa Luciani
- Unité des Virus Emergents (UVE), Aix Marseille Université, IRD 190, INSERM 1207, 13385 Marseille, France;
| | - Sophie Legrand
- Laboratoire de Parasitologie-Mycologie, Institut Hospitalo-Universitaire Méditerranée Infection, 13385 Marseille, France; (E.M.); (L.K.); (S.L.)
| | - Coralie L’Ollivier
- Laboratoire de Parasitologie-Mycologie, Institut Hospitalo-Universitaire Méditerranée Infection, 13385 Marseille, France; (E.M.); (L.K.); (S.L.)
- VITROME: Vecteurs-Infections Tropicales et Méditerranéennes, Service de Santé des Armées, Assistance Publique-Hôpitaux de Marseille, Institut de Recherche pour le Développement, Aix Marseille Université, 13385 Marseille, France
- Correspondence:
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Fijolek J, Wiatr E, Piotrowska-Kownacka D, Roszkowski-Sliz K. The role of peripheral eosinophilia in diagnosing lung disorders: experience from a single pneumonological center. Multidiscip Respir Med 2021; 16:770. [PMID: 34858593 PMCID: PMC8581820 DOI: 10.4081/mrm.2021.770] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 09/02/2021] [Indexed: 11/23/2022] Open
Abstract
Background Eosinophilia is rare but one of the important reasons to refer patients to pneumonological centers. Determining etiology of eosinophilia has practical implications for therapeutic intervention and disease prognosis. The study aimed to determine the role of peripheral eosinophilia in the diagnosis of lung disorders. Methods In this retrospective study were included 46 patients diagnosed with peripheral eosinophilia with coexisting respiratory symptoms and/or radiologically detected lung lesions. All patients underwent standard diagnostic procedures, including a detailed clinical history review, physical examination, routine laboratory tests with basal cardiological examinations, and serological tests to detect parasites and allergies. Other procedures carried out depended on the symptoms of each patient. The relation between eosinophil counts in the blood and patients’ clinical manifestation was investigated to identify the degree of eosinophilia requiring immediate diagnostic procedures and treatment. Statistical analyses were performed using scientific computation libraries in the Python programming language, SciPy, v. 1.3.1. Briefly, the following tests were used: parametric Kruskal-Wallis H test, an independent t-test, ANOVA, the Shapiro- Wilk test, Fisher’s and Chi-squared tests, and the Holm-Bonferroni method. Results Severe eosinophilia (≥5,000 cells/μl) was associated with extrapulmonary involvement and constitutional symptoms. Skin, heart, and pleural diseases were more frequent in these patients than in patients with mild or moderate eosinophilia (p=0.010, p=0.040, and p=0.007, respectively), and only these patients showed signs of kidney disease (p=0.006). Vasculitis was significantly more frequent in the severe eosinophilia group (p=0.048) than in the other two groups. In patients with moderate eosinophilia (1,500-5,000 cells/μl), extrapulmonary symptoms were less common, although signs of cardiac involvement were confirmed in 44% of subjects. In this group, vasculitis was the most commonly observed disease (42% of cases). Mild eosinophilia (<1,500 cells/μl) was mainly associated with airway disease. In this group, vasculitis and interstitial lung diseases were identified, but most were not typically connected with eosinophilia. Conclusions Identification of peripheral eosinophilia may essentially determine diagnostic procedures in patients with lung disorders and may be a useful indicator of disease etiology.
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Affiliation(s)
- Justyna Fijolek
- The Third Department of Pneumonology and Oncology, National Tuberculosis and Lung Diseases Research Institute, Warsaw
| | - Elzbieta Wiatr
- The Third Department of Pneumonology and Oncology, National Tuberculosis and Lung Diseases Research Institute, Warsaw
| | - Dorota Piotrowska-Kownacka
- The First Department of Clinical Radiology, Independent Public Central Clinical Hospital of Medical University, Warsaw, Poland
| | - Kazimierz Roszkowski-Sliz
- The Third Department of Pneumonology and Oncology, National Tuberculosis and Lung Diseases Research Institute, Warsaw
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Phasuk N, Punsawad C. Seroprevalence of Toxocara canis infection and associated risk factors among primary schoolchildren in rural Southern Thailand. Trop Med Health 2020; 48:23. [PMID: 32336929 PMCID: PMC7175560 DOI: 10.1186/s41182-020-00211-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/08/2020] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Human toxocariasis is a parasitic zoonosis caused by a parasite in the genus Toxocara and is transmitted mainly by the accidental ingestion of embryonated Toxocara canis (dog roundworm) or T. cati (cat roundworm) eggs. Several studies reported that children were the main population at risk for T. canis infection. Currently, no reports on the seroprevalence of T. canis infection in Thailand are available, and its status remains unknown among children who live in rural areas of southern Thailand. OBJECTIVE This study aimed to investigate the seroprevalence of T. canis infection and its associated risk factors among primary schoolchildren in rural areas of Nakhon Si Thammarat Province, Thailand. METHODS A total of 177 schoolchildren between 6 and 13 years of age were recruited between June and July 2019. Serum anti-T. canis IgG antibodies were detected with a commercial ELISA kit. A questionnaire administered by direct interviews was used to collect demographic and behavioral risk factor data. RESULTS The overall seroprevalence of T. canis infection was 58.2% (103 of 177). The univariate analysis revealed that schoolchildren who did not practice handwashing before a meal (crude odds ratio (COR) = 3.67, 95% CI 1.93-6.95, P < 0.001), did not practice hand washing after animal contact (COR = 2.89, 95% CI 1.53-5.47, P = 0.001), and drank untreated water (COR = 1.87, 95% CI 1.00-3.48, P = 0.049) had an increased risk of acquiring T. canis infection. However, after adjusting for confounders, only a lack of handwashing before a meal remained a significant risk factor (adjusted odds ratio (AOR) = 2.20, 95% CI 1.11-4.34, P = 0.023). Age, sex, owning a dog, and eating fresh vegetables were not significantly associated with T. canis infection in the current study. CONCLUSIONS This is the first serological investigation of T. canis infection among schoolchildren in Thailand. The high rate of Toxocara seropositivity reflected high levels of exposure to T. canis among schoolchildren in rural areas of southern Thailand. The results also provide baseline data regarding modifiable risk behaviors for effective T. canis infection prevention strategies in southern Thailand, especially strengthening hand washing practices among schoolchildren.
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Affiliation(s)
- Nonthapan Phasuk
- School of Medicine, Walailak University, Nakhon Si Thammarat, Thailand
| | - Chuchard Punsawad
- School of Medicine, Walailak University, Nakhon Si Thammarat, Thailand
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Seroprevalence of Larval Toxocarosis in the Czech Republic. Acta Parasitol 2020; 65:68-76. [PMID: 31586285 DOI: 10.2478/s11686-019-00121-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 09/09/2019] [Indexed: 01/10/2023]
Abstract
BACKGROUND Larval toxocarosis (LT), a zoonotic disease transmitted by dogs, cats, and other carnivores, is caused by roundworms of the genus Toxocara. Humans become infected by ingesting embryonated eggs of this parasite. In this study, we present data on the seroprevalence of LT in the Czech Republic collected by the National Reference Laboratory for Tissue Helminthoses in 2012-2016. METHODS Using enzyme-linked immunosorbent assay, a total of 4428 adults and children with or without clinical symptoms were examined for the presence of IgG antibodies against Toxocara canis excretory-secretory antigens. RESULTS Of all the persons examined, specific Toxocara antibodies were detected in 160 (3.6%) individuals. There were, however, significant differences between various regions, with seropositivity rates ranging from 1.4 to 7.5%. CONCLUSION In comparison to studies from 1998 and 2004, our results suggest a decrease in overall Toxocara seroprevalence in the Czech population, whereby the rates are similar to or even lower than rates in some other Central European countries.
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Seroprevalence of human toxocarosis in Europe: A review and meta-analysis. ADVANCES IN PARASITOLOGY 2020; 109:375-418. [PMID: 32381208 DOI: 10.1016/bs.apar.2020.01.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Toxocarosis is distributed worldwide and represents the most prevalent zoonotic helminth infection in industrialized countries, thereby posing a substantial risk for public health. Thus, toxocarosis is one of CDC's Neglected Parasitic Infections that has been targeted for public health action. This systematic review and meta-analysis summarizes Toxocara seroprevalence in general populations from Europe, populations suspected of Toxocara infection and defined risk groups. Random-effects meta-analysis of proportions based on 41 publications resulted in an overall seroprevalence of 6.2% (95% CI: 4.7-8.3%) in the general population of Europe. Subgroup analysis according to decades (1970-2010s) revealed a significant increase in seroprevalence, with the highest value (12.4%; 95% CI: 6.5-22.3%) in the 2010s (χ2=17.87, df=4, P=0.001). There were no significant differences between pooled prevalence rates of European sub-regions (χ2=3.01, df=3, P=0.389). Furthermore, meta-analysis of seroprevalence according to age groups, based on data from 22 publications, indicated a significantly higher pooled seroprevalence of 14.9% (95% CI: 8.5-24.8%) in people more than 50 years of age than in younger age cohorts (χ2=8.33, df=2, P=0.016). Occupational groups exposed to contaminated soil and infected animals bear substantial risk for acquiring Toxocara infection. Due to the close link between animal infection and human Toxocara exposure, a "One Health" approach for the prevention of Toxocara infection in both humans and animals is required.
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Rostami A, Ma G, Wang T, Koehler AV, Hofmann A, Chang BCH, Macpherson CN, Gasser RB. Human toxocariasis - A look at a neglected disease through an epidemiological 'prism'. INFECTION GENETICS AND EVOLUTION 2019; 74:104002. [PMID: 31412276 DOI: 10.1016/j.meegid.2019.104002] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Revised: 08/07/2019] [Accepted: 08/09/2019] [Indexed: 01/01/2023]
Abstract
Toxocariasis, a disease caused by infection with larvae of Toxocara canis, T. cati and/or congeners, represents clinical syndromes in humans including visceral and ocular larva migrans, neurotoxocariasis and covert/common toxocariasis. It is reported to be one of the most widespread public health and economically important zoonotic parasitic infections that humans share with dogs, wild canids, including foxes, and possibly other mammals. Humans become infected by accidental ingestion of embryonated Toxocara eggs, or larvae from tissues from domestic or wild paratenic hosts. Most infections are asymptomatic, and human disease may go unnoticed, as clinical investigation is often not pursued and/or diagnostic testing not conducted. Sometimes toxocariasis can be associated with complications, such as allergic and/or neurological disorders, possibly including cognitive or developmental delays in children. There is no anti-toxocariasis vaccine, and chemotherapy in humans varies, depending on symptoms and location of larvae, and may include the administration of albendazole or mebendazole, together with anti-inflammatory corticosteroids. Some recent studies indicate that toxocariasis is having an increased, adverse impact on human health in some, particularly underprivileged, tropical and subtropical communities around the world. Although tens of millions of people, especially children, are expected to be exposed to, or infected with Toxocara species, there is limited precise epidemiological data or information on the relationship between seropositivity and disease (toxocariasis) on a global scale. To gain an improved insight into this area, the present article reviews salient clinical aspects of human toxocariasis and the epidemiology of this disease, with particular reference to seroprevalence, and discusses future research and approaches/measures to understand and prevent/control this socioeconomically important, yet neglected zoonosis.
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Affiliation(s)
- Ali Rostami
- Infectious Diseases and Tropical Medicine Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
| | - Guangxu Ma
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
| | - Tao Wang
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
| | - Anson V Koehler
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
| | - Andreas Hofmann
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
| | - Bill C H Chang
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia
| | - Calum N Macpherson
- School of Graduate Studies, St. George's University, Grenada; School of Veterinary Medicine, St. George's University, Grenada; Windward Islands Research and Education Foundation, Grenada
| | - Robin B Gasser
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, Victoria, Australia.
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Abstract
Toxocara canis is an important zoonotic roundworm distributed worldwide. The infective larvae of T. canis are one of the causes of visceral larva migrans (VLM), a clinical syndrome in humans. Diagnosing VLM is difficult, and the differential diagnosis of the larval development stage is limited. Therefore, this experimental research aimed to diagnose T. canis larvae using a molecular method, not only in liver tissue, which is the most commonly affected tissue, but also in the limb muscles, lungs and brain tissues. For this purpose, 24 BALB/c mice were infected with 1000 embryonated T. canis eggs. Necropsies were performed on the second, fourth, seventh and 14th days post-infection. While a part of the samples were digested with pepsin-HCl, the molecular method was used for the remainder of the samples to replicate the mitochondrial DNA adenosine triphosphate (ATP) synthase subunit-6 gene region of T. canis. BbsI, a restriction endonuclease, was used to determine the specificity of the amplicons obtained from Polymerase chain reaction (PCR). The detection limit for embryonated eggs was recorded. The PCR results showed that the sensitivity of the PCR analysis was 83.3% in the liver (with 88.8% accuracy), 87.5% in the lungs (with 91.6% accuracy) and 75.0% in the brain, forelimb and hindlimb muscles (with 83.3% accuracy). In all tissues, the test specificity was determined to be 100%. In this study, the molecular method was applied to only experimentally infected BALB/c mice tissues; thus, it is suggested that it can be also employed in different paratenic hosts and materials possibly infected with T. canis.
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Inchauspe S, Echandi LV, Dodds EM. Diagnosis of ocular toxocariasis by detecting antibodies in the vitreous humor. ACTA ACUST UNITED AC 2019; 93:220-224. [PMID: 29402497 DOI: 10.1016/j.oftal.2017.11.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 11/15/2017] [Accepted: 11/15/2017] [Indexed: 11/18/2022]
Abstract
OBJECTIVES To demonstrate the production of the local toxocara antibodies in the vitreous of patients with negative serology. MATERIAL AND METHODS Retrospective review of the medical records of patients seen in a Tertiary Referral Hospital, and at an Eye Institute, with an ocular diagnosis of toxocariasis who had a negative serology and positive titres in the vitreous. RESULTS After reviewing the medical records of 40 patients with a diagnosis of ocular toxocariasis, a total of six cases (15%) were found with a negative serology and a positive vitreous titre for toxocara antibody, both of them performed using an ELISA procedure. The mean age was 18 years, there were no differences observed between males and females. A peripheral granuloma was the most common clinic finding, and all patients underwent vitrectomy either to remove epiretinal membranes or to repair retinal detachments. CONCLUSION A negative serology does not rule out a diagnosis of ocular toxocariasis. Vitreous samples may be necessary to confirm a clinical diagnosis.
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Affiliation(s)
- S Inchauspe
- Consultores Oftalmológicos, Buenos Aires, Argentina
| | - L V Echandi
- Consultores Oftalmológicos, Buenos Aires, Argentina
| | - E M Dodds
- Consultores Oftalmológicos, Hospital Juan A. Fernandez, Buenos Aires, Argentina.
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Mutombo PN, Man NWY, Nejsum P, Ricketson R, Gordon CA, Robertson G, Clements ACA, Chacón-Fonseca N, Nissapatorn V, Webster JP, McLaws ML. Diagnosis and drug resistance of human soil-transmitted helminth infections: A public health perspective. ADVANCES IN PARASITOLOGY 2019; 104:247-326. [PMID: 31030770 DOI: 10.1016/bs.apar.2019.02.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Soil-transmitted helminth (STH) infections represent a major public health problem globally, particularly among socio-economically disadvantaged populations. Detection of STH infections is often challenging, requiring a combination of diagnostic techniques to achieve acceptable sensitivity and specificity, particularly in low infection-intensity situations. The microscopy-based Kato-Katz remains the most widely used method but has low sensitivity in the detection of, for instance, Strongyloides spp. infections, among others. Antigen/antibody assays can be more sensitive but are parasite species-specific. Highly sensitive PCR methods have been developed to be multiplexed to allow multi-species detection. Novel diagnostic tests for all STH species are needed for effective monitoring, evaluation of chemotherapy programmes, and to assess the potential emergence of parasite resistance. This review discusses available diagnostic methods for the different stages of STH control programmes, which vary in sensitivity and spectrum of detection requirements, and tools to evaluate drug efficacy and resistance.
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Affiliation(s)
- Polydor Ngoy Mutombo
- School of Public Health and Community Medicine, UNSW Medicine, UNSW, Sydney, NSW, Australia; Centre for Biomedical Research, Burnet Institute, Melbourne, VIC, Australia.
| | - Nicola W Y Man
- Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Peter Nejsum
- Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Robert Ricketson
- Hale O'mana'o Biomedical Research, Division of Emerging Pathogens, Edmond, OK, United States
| | - Catherine A Gordon
- Molecular Parasitology Laboratory, Infectious Diseases Division, QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia
| | - Gemma Robertson
- Public and Environmental Health, Forensic and Scientific Services, Department of Health, Brisbane, QLD, Australia
| | | | - Nathalie Chacón-Fonseca
- Soil-Transmitted Helminths Section, Tropical Medicine Institute, Tropical Medicine Department, Faculty of Medicine, Central University of Venezuela, Caracas, Venezuela
| | - Veeranoot Nissapatorn
- School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat, Thailand; Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Nakhon Si Thammarat, Thailand
| | - Joanne P Webster
- Centre for Emerging, Endemic and Exotic Diseases (CEEED), Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, London, United Kingdom
| | - Mary-Louise McLaws
- School of Public Health and Community Medicine, UNSW Medicine, UNSW, Sydney, NSW, Australia.
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13
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Ma G, Holland CV, Wang T, Hofmann A, Fan CK, Maizels RM, Hotez PJ, Gasser RB. Human toxocariasis. THE LANCET. INFECTIOUS DISEASES 2018; 18:e14-e24. [PMID: 28781085 DOI: 10.1016/s1473-3099(17)30331-6] [Citation(s) in RCA: 247] [Impact Index Per Article: 41.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 04/21/2017] [Accepted: 05/11/2017] [Indexed: 12/25/2022]
Abstract
Parasitic nematodes of the genus Toxocara are socioeconomically important zoonotic pathogens. These parasites are usually directly transmitted to the human host via the faecal-oral route and can cause toxocariasis and associated complications, including allergic and neurological disorders. Although tens of millions of people are estimated to be exposed to or infected with Toxocara spp, global epidemiological information on the relationship between seropositivity and toxocariasis is limited. Recent findings suggest that the effect of toxocariasis on human health is increasing in some countries. Here we review the salient background on Toxocara and biology, summarise key aspects of the pathogenesis, diagnosis, and treatment of toxocariasis, describe what is known about its geographic distribution and prevalence, and make some recommendations for future research towards the prevention and control of this important disease.
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Affiliation(s)
- Guangxu Ma
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, VIC, Australia
| | - Celia V Holland
- Department of Zoology, School of Natural Sciences, Trinity College, Dublin, Ireland
| | - Tao Wang
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, VIC, Australia
| | - Andreas Hofmann
- Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD, Australia
| | - Chia-Kwung Fan
- Department of Molecular Parasitology and Tropical Diseases, School of Medicine & Research Center of International Tropical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Rick M Maizels
- Wellcome Centre for Molecular Parasitology, Institute for Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK
| | - Peter J Hotez
- Texas Children's Hospital Center for Vaccine Development, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA; Department of Pediatrics, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA; Department of Molecular Virology & Microbiology, National School of Tropical Medicine, Baylor College of Medicine, Houston, TX, USA
| | - Robin B Gasser
- Department of Veterinary Biosciences, Melbourne Veterinary School, The University of Melbourne, Parkville, VIC, Australia.
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14
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Novák J, Panská L, Macháček T, Kolářová L, Horák P. Humoral response of mice infected with Toxocara canis following different infection schemes. Acta Parasitol 2017; 62:823-835. [PMID: 29035857 DOI: 10.1515/ap-2017-0099] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 08/11/2017] [Indexed: 12/19/2022]
Abstract
The study was focused on the dynamics of humoral response to Toxocara canis excretory-secretory antigens (TES antigens) in mice experimentally infected by T. canis L3 larvae in different ways. In particular, we compared the effect of infection with two doses of 1000 larvae vs. repeated infections with a low number of larvae (daily infection with 10 larvae and weekly infection with 100 larvae in the course of 22 weeks). In ELISA, all infections, including both schemes with lower larval doses, elicited significant antibody response. Elevated levels of total IgE and TES-antigen-specific IgM were detected on day 12 after the first infection, followed by IgG and IgG1, and later by IgG3, IgG2a and IgG2b; specific IgE response was not detected. It seems that the high levels of IgM and IgG1 represent the best markers of infection. In addition, gradual increase of IgG2a and IgG2b could help in determination of the infection course. As a byproduct of our work, a new method of infection by repeated drinking of larvae was introduced; it minimizes the pain and discomfort for the experimental mice.
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15
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Assessment of the diagnostic value of specific anti-Toxocara IgA in Slovakian patients suspected to have toxocarosis. Folia Microbiol (Praha) 2017; 63:345-351. [PMID: 29214527 DOI: 10.1007/s12223-017-0572-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 11/23/2017] [Indexed: 10/18/2022]
Abstract
Human toxocarosis is one of the most widespread and prevalent helminthic zoonosis in many countries, including Slovakia. The aim was to evaluate the usefulness of IgA anti-Toxocara antibody detection in the serodiagnosis of toxocarosis. The levels of specific IgA antibodies were determined by excretory-secretory (ES)-enzyme-linked immunosorbent assay (ELISA). The IgA seropositivity in IgG anti-Toxocara seropositive patients (n = 52) was 32.7% and found to be highest in the oldest age groups (P = 0.026). The presence of IgA in suspected patients for toxocarosis were evaluated in respect to some characteristics of examined persons. Substantially higher IgA seropositivity was detected in patients with increased total IgE (44.8%) than in subjects with a normal level of IgE (17.4%; P = 0.036). No associations (P > 0.05) were found between IgA seropositivity and sex, level of specific IgG antibodies, avidity of IgG, eosinophilia, domicile, geophagia, traveling abroad, dog/cat ownership, or clinical symptoms. The IgA-ELISA showed sensitivity of 57.1% and specificity of 100%. Mild correlations (r = 0.302, r = 0.305, r = - 0.409) were observed between the levels of anti-Toxocara IgA antibodies and age, the amounts of eosinophils and IgA antibody levels, the amounts of eosinophils, and the values of IgG avidity, respectively. The presence of anti-Toxocara IgA may facilitate the diagnosis of toxocarosis and may well be useful for the determination of acute Toxocara infection. Moreover, this test should be accompanied by other immunological markers of examined patients (e.g., increased total IgE, eosinophilia, and low-avidity IgG antibodies).
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