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Memorias Do Instituto Oswaldo Cruz May 2017Amphimerus spp. is a liver fluke that infects humans and domestic animals. It is highly prevalent in some Ecuadorian communities. Currently, diagnosis is based on the...
BACKGROUND
Amphimerus spp. is a liver fluke that infects humans and domestic animals. It is highly prevalent in some Ecuadorian communities. Currently, diagnosis is based on the microscopic observation of eggs in faeces, but this has variable sensitivity. More sensitive methods are needed for diagnostic testing.
OBJECTIVE
The main objective of this work was to develop an enzyme-linked immunosorbent assay (ELISA) using crude antigens from Amphimerus spp. adult worms to detect anti-Amphimerus IgG in human sera.
METHODS
Crude somatic antigens were obtained from adult Amphimerus spp. worms. Human sera from 119 patients were tested: 48 from individuals with a confirmed Amphimerus spp. infection, 78 from non-infected Ecuadorians living in the endemic region, 60 from persons living in non-endemic areas (20 Ecuadorians, 20 Europeans, and 20 Africans), and 33 who had other parasitic and non-parasitic infections.
PRINCIPAL FINDINGS
Results were analysed using the receiver-operator characteristic (ROC) curve analysis with an area under curve (AUC) value of 0.967. The accuracy of the ELISA was high. The sensitivity was 85.0% [95% confidence interval (CI): 80.3-89.7%] and the specificity was 71.0% (95% CI: 65.2-76.8%). Some cross reactivity was detected against Paragonimus mexicanus, Fasciola hepatica, Schistosomiasis, Taenia solium, Strongyloides stercoralis, Mansonella spp., and Vampirolepis nana.
MAIN CONCLUSIONS
We have developed the first ELISA technique that detects anti-Amphimerus IgG in human sera with good sensitivity, repeatability and reproducibility. However, more specific antigens are needed to further enhance performance of this assay. Regardless, this ELISA test could be useful for early diagnosis and prompt treatment of human Amphimerus spp. infections.
Topics: Animals; Antibodies, Helminth; Antigens, Helminth; Area Under Curve; Enzyme-Linked Immunosorbent Assay; Humans; Immunoglobulin G; Opisthorchidae; ROC Curve; Reproducibility of Results; Sensitivity and Specificity; Trematode Infections
PubMed: 28443982
DOI: 10.1590/0074-02760160426 -
International Journal For Parasitology.... Aug 2017Parasite-host relationships are influenced by several factors intrinsic to hosts, such as social standing, group membership, sex, and age. However, in wild populations,...
Parasite-host relationships are influenced by several factors intrinsic to hosts, such as social standing, group membership, sex, and age. However, in wild populations, temporal variation in parasite distributions and concomitant infections can alter these patterns. We used microscropy and molecular methods to screen for naturally occurring haemoparasitic infections in two Neotropical primate host populations, the saddleback () and emperor () tamarin, in the lowland tropical rainforests of southeastern Peru. Repeat sampling was conducted from known individuals over a three-year period to test for parasite-host and parasite-parasite associations. Three parasites were detected in including , , spp., while only hosted the latter two. Temporal variation in prevalence was observed in and spp, confirming the necessity of a multi-year study to evaluate parasite-host relationships in this system. Although callitrichids display a distinct reproductive dominance hierarchy, characterized by single breeding females that typically mate polyandrously and can suppress the reproduction of subdominant females, logistic models did not identify sex or breeding status as determining factors in the presence of these parasites. However, age class had a positive effect on infection with and , and adults demonstrated higher parasite species richness than juveniles or sub-adults across both species. Body weight had a positive effect on the presence of spp. The inclusion of co-infection variables in statistical models of parasite presence/absence data improved model fit for two of three parasites. This study verifies the importance and need for broad spectrum and long-term screening of parasite assemblages of natural host populations.
PubMed: 28393014
DOI: 10.1016/j.ijppaw.2017.03.004 -
Emerging Infectious Diseases Mar 2017We obtained ribosomal and mitochondrial DNA sequences from residents of Amazonas state, Brazil, with Mansonella parasitemias. Phylogenetic analysis of these sequences...
We obtained ribosomal and mitochondrial DNA sequences from residents of Amazonas state, Brazil, with Mansonella parasitemias. Phylogenetic analysis of these sequences confirm that M. ozzardi and M. perstans parasites occur in sympatry and reveal the close relationship between M. perstans in Africa and Brazil, providing insights into the parasite's New World origins.
Topics: Animals; DNA, Protozoan; DNA, Ribosomal Spacer; Humans; Mansonella; Mansonelliasis; Parasitemia; Phylogeny
PubMed: 28221120
DOI: 10.3201/eid2303.161159 -
PLoS Neglected Tropical Diseases Feb 2017Chronic parasitic infections are associated with active immunomodulation which may include by-stander effects on unrelated antigens. It has been suggested that pre-natal... (Randomized Controlled Trial)
Randomized Controlled Trial
The impact of prenatal exposure to parasitic infections and to anthelminthic treatment on antibody responses to routine immunisations given in infancy: Secondary analysis of a randomised controlled trial.
BACKGROUND
Chronic parasitic infections are associated with active immunomodulation which may include by-stander effects on unrelated antigens. It has been suggested that pre-natal exposure to parasitic infections in the mother impacts immunological development in the fetus and hence the offspring's response to vaccines, and that control of parasitic infection among pregnant women will therefore be beneficial.
METHODOLOGY/PRINCIPAL FINDINGS
We used new data from the Entebbe Mother and Baby Study, a trial of anthelminthic treatment during pregnancy conducted in Uganda, to further investigate this hypothesis. 2705 mothers were investigated for parasitic infections and then randomised to albendazole (400mg) versus placebo and praziquantel (40mg/kg) during pregnancy in a factorial design. All mothers received sulfadoxine/pyrimethamine for presumptive treatment of malaria. Offspring received Expanded Programme on Immunisation vaccines at birth, six, 10 and 14 weeks. New data on antibody levels to diphtheria toxin, three pertussis antigens, Haemophilus influenzae type B (HiB) and Hepatitis B, measured at one year (April 2004 -May 2007) from 1379 infants were analysed for this report. Additional observational analyses relating maternal infections to infant vaccine responses were also conducted. Helminth infections were highly prevalent amongst mothers (hookworm 43.1%, Mansonella 20.9%, Schistosoma mansoni 17.3%, Strongyloides 11.7%, Trichuris 8.1%) and 9.4% had malaria at enrolment. In the trial analysis we found no overall effect of either anthelminthic intervention on the measured infant vaccine responses. In observational analyses, no species was associated with suppressed responses. Strongyloidiasis was associated with enhanced responses to pertussis toxin, HiB and Hep B vaccine antigens.
CONCLUSIONS/SIGNIFICANCE
Our results do not support the hypothesis that routine anthelminthic treatment during pregnancy has a benefit for the infant's vaccine response, or that maternal helminth infection has a net suppressive effect on the offspring's response to vaccines.
TRIAL REGISTRATION
ISRCTN.com ISRCTN32849447.
Topics: Adult; Albendazole; Animals; Anthelmintics; Antibodies, Helminth; Antibody Formation; Female; Helminthiasis; Helminths; Humans; Immunization; Infant; Infant, Newborn; Infant, Newborn, Diseases; Male; Praziquantel; Pregnancy; Pregnancy Complications, Parasitic; Prenatal Exposure Delayed Effects; Uganda; Vaccines; Young Adult
PubMed: 28178298
DOI: 10.1371/journal.pntd.0005213 -
BMC Public Health Jan 2017Sub-Saharan Africa is undergoing an epidemiological transition from a predominance of infectious diseases to non-communicable and lifestyle related conditions. However,...
Demography, maternal health and the epidemiology of malaria and other major infectious diseases in the rural department Tsamba-Magotsi, Ngounie Province, in central African Gabon.
BACKGROUND
Sub-Saharan Africa is undergoing an epidemiological transition from a predominance of infectious diseases to non-communicable and lifestyle related conditions. However, the pace of this transition and the pattern of disease epidemiology are uneven between affluent urban and rural poor populations. To address this question for a remote rural region located in the central African rainforest region of Gabon, this study was conducted to assess reasons for health care attendance and to characterize the epidemiology of malaria and other major infectious diseases for the department of Tsamba Magotsi.
METHODS
Major causes for health care attendance were collected from local hospital records. Cross sectional population based surveys were performed for the assessment of local malaria epidemiology. Pregnant women attending antenatal care services were surveyed as a sentinel population for the characterization of chronic viral and parasitic infections in the community.
RESULTS
Infectious diseases were responsible for 71% (7469) of a total of 10,580 consultations at the formal health care sector in 2010. Overall, malaria - defined by clinical syndrome - remained the most frequent cause for health care attendance. A cross sectional malaria survey in 840 asymptomatic individuals residing in Tsamba Magotsi resulted in a Plasmodium spp. infection prevalence of 37%. The infection rate in 2-10 year old asymptomatic children - a standard measure for malaria endemicity - was 46% (100 of 217) with P. falciparum as predominant species (79%). Infection with other plasmodial species (P. ovale and P. malariae) presented most commonly as coinfections (23.2%). Prevalence of HIV, HBV, and syphilis were 6.2, 7.3, and 2.5%, respectively, in cross-sectional assessments of antenatal care visits of pregnant women. Urogenital schistosomiasis and the filarial pathogens Loa loa and Mansonella perstans are highly prevalent chronic parasitic infections affecting the local population.
CONCLUSIONS
Despite major improvements in the accessibility of Tsamba Magotsi over the past decade the epidemiological transition does not appear to have majorly changed on the spectrum of diseases in this rural Gabonese population. The high prevalence of Plasmodium infection indicates a high burden of malaria related morbidity. Infectious diseases remain one of the most important health issues and further research activities in the field of tropical medicine and infectious diseases could help improve health care for the local population.
Topics: Adult; Cross-Sectional Studies; Female; Gabon; Humans; Malaria; Maternal Health; Pregnancy; Pregnancy Complications, Infectious; Pregnancy Complications, Parasitic; Pregnant Women; Prenatal Care; Prevalence; Rural Population
PubMed: 28129759
DOI: 10.1186/s12889-017-4045-x -
Parasites & Vectors Jan 2017Mansonellosis was first reported in Ghana by Awadzi in the 1990s. Co-infections of Mansonella perstans have also been reported in a small cohort of patients with Buruli...
BACKGROUND
Mansonellosis was first reported in Ghana by Awadzi in the 1990s. Co-infections of Mansonella perstans have also been reported in a small cohort of patients with Buruli ulcer and their contacts. However, no study has assessed the exact prevalence of the disease in a larger study population. This study therefore aimed to find out the prevalence of M. perstans infection in some districts in Ghana and to determine the diversity of Culicoides that could be potential vectors for transmission.
METHODS
From each participant screened in the Asante Akim North (Ashanti Region), Sene West and Atebubu Amantin (Brong Ahafo Region) districts, a total of 70 μl of finger prick blood was collected for assessment of M. perstans microfilariae. Centre for Disease Control (CDC) light traps as well as the Human Landing Catch (HLC) method were used to assess the species diversity of Culicoides present in the study communities.
RESULTS
From 2,247 participants, an overall prevalence of 32% was recorded although up to 75% prevalence was demonstrated in some of the communities. Culicoides inornatipennis was the only species of Culicoides caught with the HLC method. By contrast, C. imicola (47%), C. neavei (25%) and C. schultzei (15%) were caught by the CDC light trap method. A wide diversity of other Culicoides spp. was also identified but correlation was only found between the prevalence of C. inornatipennis and M. perstans during the dry season.
CONCLUSIONS
Here we demonstrate for the first time that M. perstans is highly prevalent in three districts in Ghana. We found a wide spectrum of Culicoides spp. Culicoides inornatipennis was the most anthropophilic and is therefore likely to be the species responsible for transmission of infection but formal proof has yet to be obtained.
TRIAL REGISTRATION
NCT02281643 . Registered October 26, 2014. 'Retrospectively registered'.
TRIAL REGISTRY
ClinicalTrials.gov.
Topics: Animals; Ceratopogonidae; Ghana; Humans; Insect Vectors; Mansonella; Mansonelliasis; Prevalence; Retrospective Studies
PubMed: 28061905
DOI: 10.1186/s13071-016-1960-0 -
Germs Dec 2016is a human filarial parasite transmitted by biting midges (Diptera: Ceratopogonidae) belonging to the genus and it is widely spread in sub-Saharan Africa. While most...
INTRODUCTION
is a human filarial parasite transmitted by biting midges (Diptera: Ceratopogonidae) belonging to the genus and it is widely spread in sub-Saharan Africa. While most cases are asymptomatic, mansonelliasis can be associated with angioedema, arthralgia, swellings, pain in the scrotum or in serous cavities such as the pleura, the peritoneum, the pericardium, etc. Mansonelliasis can be really hard to treat, but it has been shown that an intensive treatment using albendazole can clear the parasite.
CASE REPORT
Here we describe a case of a 16 months-old malnourished child with pneumonia due to in the east of the Democratic Republic of Congo.
CONCLUSION
Although our investigations confirmed infection, this case shows that it is very difficult to come to a conclusive diagnosis.
PubMed: 28053918
DOI: 10.11599/germs.2016.1101 -
The American Journal of Tropical... Sep 2016Mansonellosis is endemic in several regions of Africa, the Caribbean, and Latin America. Mansonella ozzardi and Mansonella perstans have been reported in Latin America,...
Mansonellosis is endemic in several regions of Africa, the Caribbean, and Latin America. Mansonella ozzardi and Mansonella perstans have been reported in Latin America, including the Amazon region. A morphological and molecular microfilariae study was performed in Pauini (Brazil). Blood samples were collected from 40 individuals, and were analyzed by Giemsa-stained blood film and by two different nested polymerase chain reactions which detect internal transcribed spacer-1 and the major sperm protein gene. By microscopy, 14 of 40 were positive: 11 as M. ozzardi and three as M. perstans-like infections. Both molecular methods detected 19 positive cases as M. ozzardi, including those 14 individuals detected by microscopy, without detectable genetic differences among any of the 19 positive samples. Molecular techniques showed an improvement of mansonellosis diagnosis and may become an effective tool to evaluate the present status of M. ozzardi and M. perstans in Latin America.
Topics: Animals; Brazil; Humans; Mansonella; Mansonelliasis; Microfilariae; Microscopy; Phylogeny; Polymerase Chain Reaction
PubMed: 27402517
DOI: 10.4269/ajtmh.15-0654 -
Pathogens and Global Health May 2016Mansonella ozzardi (Nematoda: Onchocercidae) is an understudied filarial nematode, originally described by Patrick Manson in 1897, that can be transmitted by two... (Review)
Review
Mansonella ozzardi (Nematoda: Onchocercidae) is an understudied filarial nematode, originally described by Patrick Manson in 1897, that can be transmitted by two families of dipteran vectors, biting midges (most of them members of the genus Culicoides) and black flies (genus Simulium). With a patchy geographic distribution from southern Mexico to northwestern Argentina, human infection with M. ozzardi is highly prevalent in some of the Caribbean islands, along riverine communities in the Amazon Basin, and on both sides of the border between Bolivia and Argentina. There is no clinical entity unequivocally associated with M. ozzardi infection, although fever, arthralgia, headache, cold lower extremities, and itchy cutaneous rashes are occasionally mentioned in case report series. More recently, ocular manifestations (especially keratitis) have been associated with mansonelliasis, opening an important area of investigation. Here, we briefly review the biology, epidemiology, pathogenesis, and clinical aspects of M. ozzardi infection and point to some existing knowledge gaps, aiming to stimulate a research agenda to help filling them.
Topics: Animals; Anthelmintics; Arthropod Vectors; Humans; Mansonella; Mansonelliasis; Neglected Diseases; Prevalence
PubMed: 27376501
DOI: 10.1080/20477724.2016.1190544 -
BMC Infectious Diseases Jun 2016Human dirofilariosis is still a little known infection even in endemic areas. Dirofilariosis is zoonotic infection usually abortive in humans; instead, we report a very...
BACKGROUND
Human dirofilariosis is still a little known infection even in endemic areas. Dirofilariosis is zoonotic infection usually abortive in humans; instead, we report a very rare case (the 4th in the world), the first in Italy, in which at least two infective larvae became mature adults that mated and produced active microfilariae even though they did not reach peripheral blood.
CASE PRESENTATION
A 30-year-old Italian woman presented with a transient oedematous swelling on the left abdominal wall with a creeping eruption followed by the occurrence of a subcutaneous nodular painless mass in the iliac region. One month later, a similar temporary swelling appeared on the contralateral inguinal region associated with intermittent joint discomfort in both knees. The patient had recently travelled abroad, therefore many possible diagnoses were to be ruled out. Routine laboratory investigations revealed eosinophilia. An ultrasound examination of the iliac swelling evidenced a well-defined cyst with a big filamentous formation in continuous movement. A fine-needle aspiration of the lesion was performed for parasitological, cytological and histological exams. The prompt microscopic examination of the aspired material showed the presence of numerous microfilariae that were initially morphologically attributed to Mansonella ozzardi. Subsequently, the revision of the Giemsa stained film and molecular analyses of the biological material, allowed to identify Dirofilaria repens as etiological agent of infection.
CONCLUSIONS
We report of a case in whom microfilariae were detected in fine-needle aspirate of subcutaneous node, without evidence of microfilaraemia, and the infection failed to become fully patent. Therefore we confirm that complete development and fertilization of D. repens worms in human hosts may occur, at variance with what is commonly believed, that Dirofilaria worms cannot fully develop in humans.
Topics: Adult; Animals; Biopsy, Fine-Needle; Diagnosis, Differential; Dirofilaria repens; Dirofilariasis; Female; Humans; Italy; Lymph Nodes; Mansonella; Mansonelliasis; Microfilariae; Needles; Polymerase Chain Reaction
PubMed: 27266512
DOI: 10.1186/s12879-016-1582-3