Dirofilaria repens is a nematode affecting domestic and wild canids, transmitted by several species of mosquitoes. It usually causes a non-pathogenic subcutaneous infection in dogs and is the ...principal agent of human dirofilariosis in the Old World. In the last decades, D. repens has increased in prevalence in areas where it has already been reported and its distribution range has expanded into new areas of Europe, representing a paradigmatic example of an emergent pathogen. Despite its emergence and zoonotic impact, D. repens has received less attention by scientists compared to Dirofilaria immitis. In this review we report the recent advances of D. repens infection in dogs and humans, and transmission by vectors, and discuss possible factors that influence the spread and increase of this zoonotic parasite in Europe. There is evidence that D. repens has spread faster than D. immitis from the endemic areas of southern Europe to northern Europe. Climate change affecting mosquito vectors and the facilitation of pet travel seem to have contributed to this expansion; however, in the authors' opinion, the major factor is likely the rate of undiagnosed dogs continuing to perpetuate the life-cycle of D. repens. Many infected dogs remain undetected due to the subclinical nature of the disease, the lack of rapid and reliable diagnostic tools and the poor knowledge and still low awareness of D. repens in non-endemic areas. Improved diagnostic tools are warranted to bring D. repens diagnosis to the state of D. immitis diagnosis, as well as improved screening of imported dogs and promotion of preventative measures among veterinarians and dog owners. For vector-borne diseases involving pets, veterinarians play a significant role in prevention and should be more aware of their responsibility in reducing the impact of the zoonotic agents. In addition, they should enhance multisectorial collaboration with medical entomologists and the public health experts, under the concept and the actions of One Health-One Medicine.
The increasing incidence of infections caused by extended-spectrum beta-lactamase (ESBL)-producing
in sub-Saharan Africa is of serious concern. Studies from countries with a highly industrialized ...poultry industry suggest the poultry production-food-consumer chain as a potential transmission route. In Africa, integrated studies at this human-animal interface are still missing.
To determine the molecular epidemiology of ESBL-producing
from the intestinal tract of humans and poultry in rural Ghana.
During a 6-month period, fecal samples from all children admitted to the Agogo Hospital (Ghana) and broilers at eight poultry farms located within the hospital catchment area were collected. After screening on selective ESBL agar, whole genome sequencing (WGS) was performed on all ESBL isolates. The genomes were analyzed using multilocus sequence typing (MLST), ESBL genotyping and genome-based phylogenetic analyses.
Of 140 broilers and 54 children, 41 (29%) and 33 (61%) harbored ESBL
, respectively, with prevalences on farms ranging between 0 and 85%. No predominant sequence type (ST) was detected among humans. ST10 was most prevalent among broilers (
= 31, 69%). The ESBL gene
was predominant among broilers (
= 43, 96%) and humans (
= 32, 97%). Whole-genome-based phylogenetic analysis revealed three very closely related broiler/human isolate clusters (10% of ESBL isolates) with chromosomal and plasmid-mediated ESBL genes.
The findings demonstrate a high frequency of intestinal ESBL-producing
in rural Ghana. Considering that animal and human samples are independent specimens from the same geographic location, the number of closely related ESBL isolates circulating across these two reservoirs is substantial. Hence, poultry farms or meat products might be an important source for ESBL-producing bacteria in rural Ghana leading to difficult-to-treat infections in humans.
•In southwest Madagascar, people and their livestock as well as endemic mammals are exposed to a variety of ectoparasite species harboring rickettsiae, borreliae, bartonellae and/or Y. pestis.•Each ...of the 13 examined ectoparasite species was found to carry at least one species of potentially pathogenic bacteria.•Rickettsia africae revealed a considerably wide distribution: 12 out of 13 ectoparasite species were positive for R. africae DNA.•The finding of a rat and its fleas being infected with Y. pestis raises questions about the distribution and the risk of transmission of Y. pestis in the lowland of Madagascar.
Little is known about the presence of vector-borne bacteria in southwest Madagascar. Anthropogenic alteration of natural habitats represents an important driver for the emergence of new diseases. Especially the involvement of livestock and the involuntary maintaining of invasive synanthropic animals (particularly rats) facilitate disease transmission from wildlife to humans and associated animals and vice versa. The dissemination or acquisition of ectoparasites is most likely in regions where human/wildlife contact is increasing. Little is known about the presence of vector-borne bacteria in southwest Madagascar. In 2016 and 2017, ectoparasites were collected from various introduced (cattle and goats, cats, dogs and chicken, rats and mice) and native animal species (mouse lemurs Microcebus griseorufus, Grandidier's mongooses Galidictis grandidieri, bastard big-footed mice Macrotarsomys bastardi, greater hedgehog tenrecs Setifer setosus and lesser hedgehog tenrecs Echinops telfairi) in the northern portion of Tsimanampetsotsa National Park and the adjacent littoral region. Thirteen species of blood-feeding ectoparasites (235 individuals of ticks 5 species, 414 lice 4 spp. and 389 fleas 4 spp.) were investigated for the presence and identity of rickettsiae, borreliae, bartonellae and Yersinia pestis using PCR techniques. Rickettsia spp. were detected in every single ectoparasite species (Amblyomma variegatum, A. chabaudi, Rhipicephalus microplus, Haemaphysalis simplex, Argas echinops, Ctenocephalides felis, Echidnophaga gallinacea, Pulex irritans, Xenopsylla cheopis, Haematopinus quadripertusus, Linognathus africanus, L. vituli, Lemurpediculus verruculosus). Lice and ticks were found harboring rickettsiae identified as Rickettsia africae, while Rickettsia felis-like bacteria were associated with fleas. Borrelia spp. were detected in 5% of H. simplex and 1% of R. microplus ticks. Bartonella spp. were detected in 40% of H. quadripertusus pools and in 5% of L. verruculosus pools. Y. pestis was detected in X. cheopis and E. gallinacea fleas collected from a rat. This study presents the detection of a broad spectrum of vector-borne bacteria including potential pathogens, and an unexpected finding of Y. pestis far off the known plague foci in Madagascar.
Matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS) has become a widely used technique for the rapid and accurate identification of bacteria, mycobacteria ...and certain fungal pathogens in the clinical microbiology laboratory. Thus far, only few attempts have been made to apply the technique in clinical parasitology, particularly regarding helminth identification.
We systematically reviewed the scientific literature on studies pertaining to MALDI-TOF MS as a diagnostic technique for helminths (cestodes, nematodes and trematodes) of medical and veterinary importance. Readily available electronic databases (i.e. PubMed/MEDLINE, ScienceDirect, Cochrane Library, Web of Science and Google Scholar) were searched from inception to 10 October 2018, without restriction on year of publication or language. The titles and abstracts of studies were screened for eligibility by two independent reviewers. Relevant articles were read in full and included in the systematic review.
A total of 84 peer-reviewed articles were considered for the final analysis. Most papers reported on the application of MALDI-TOF for the study of Caenorhabditis elegans, and the technique was primarily used for identification of specific proteins rather than entire pathogens. Since 2015, a small number of studies documented the successful use of MALDI-TOF MS for species-specific identification of nematodes of human and veterinary importance, such as Trichinella spp. and Dirofilaria spp. However, the quality of available data and the number of examined helminth samples was low.
Data on the use of MALDI-TOF MS for the diagnosis of helminths are scarce, but recent evidence suggests a potential role for a reliable identification of nematodes. Future research should explore the diagnostic accuracy of MALDI-TOF MS for identification of (i) adult helminths, larvae and eggs shed in faecal samples; and (ii) helminth-related proteins that are detectable in serum or body fluids of infected individuals.
Molecular diagnostic approaches are increasingly included in the diagnostic workup and even in the primary diagnosis of malaria in non-endemic settings, where it is difficult to maintain skillful ...microscopic malaria detection due to the rarity of the disease. Pathogen-specific nucleic acid amplification, however, bears the risk of overlooking other pathogens associated with febrile illness in returnees from the tropics. Here, we assessed the discriminatory potential of metagenomic sequencing for the identification of different Plasmodium species with various parasitemia in EDTA blood of malaria patients. Overall, the proportion of Plasmodium spp.-specific sequence reads in the assessed samples showed a robust positive correlation with parasitemia (Spearman r = 0.7307, p = 0.0001) and a robust negative correlation with cycle threshold (Ct) values of genus-specific real-time PCR (Spearman r = −0.8626, p ≤ 0.0001). Depending on the applied bioinformatic algorithm, discrimination on species level was successful in 50% (11/22) to 63.6% (14/22) instances. Limiting factors for the discrimination on species level were very low parasitemia, species-depending lacking availability of reliable reference genomes, and mixed infections with high variance of the proportion of the infecting species. In summary, metagenomic sequencing as performed in this study is suitable for the detection of malaria in human blood samples, but the diagnostic detection limit for a reliable discrimination on species level remains higher than for competing diagnostic approaches like microscopy and PCR.
The potential of next-generation sequencing (NGS) for hypothesis-free pathogen diagnosis from (poly-)microbially contaminated, formalin-fixed, paraffin embedded tissue samples from patients with ...invasive fungal infections and amebiasis was investigated. Samples from patients with chromoblastomycosis (n = 3), coccidioidomycosis (n = 2), histoplasmosis (n = 4), histoplasmosis or cryptococcosis with poor histological discriminability (n = 1), mucormycosis (n = 2), mycetoma (n = 3), rhinosporidiosis (n = 2), and invasive Entamoeba histolytica infections (n = 6) were analyzed by NGS (each one Illumina v3 run per sample). To discriminate contamination from putative infections in NGS analysis, mean and standard deviation of the number of specific sequence fragments (paired reads) were determined and compared in all samples examined for the pathogens in question.
For matches between NGS results and histological diagnoses, a percentage of species-specific reads greater than the 4th standard deviation above the mean value of all 23 assessed sample materials was required. Potentially etiologically relevant pathogens could be identified by NGS in 5 out of 17 samples of patients with invasive mycoses and in 1 out of 6 samples of patients with amebiasis.
The use of NGS for hypothesis-free pathogen diagnosis from contamination-prone formalin-fixed, paraffin-embedded tissue requires further standardization.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Zoonotic larvae of the family Anisakidae found in several fish species represent a serious risk in public health since they may cause food-borne anisakidosis in humans. Chile has culinary preferences ...including eating raw fish in many traditional preparations. In the present study, a total of 180 fish specimens representing three different fish species, i.e., Chilean hake (
Merluccius gayi
), snoek (
Thyrsites atun
), and sea bream (
Brama australis
), were caught at central coast of Chile. Parasitological examination was performed on musculature and abdominal cavity for subsequent extraction and quantification of anisakid larvae. Estimation of infection parameters, such as prevalence, was performed indicating 100% (CI: 0.94–1.0) prevalence of anisakid L3 in Chilean hakes and snoeks
.
Moreover, sea breams reached a prevalence of 35% (CI: 0.23–0.48). Prevalence of anisakid larvae in muscle was also analyzed showing values of 18.6% (CI: 0.097–0.309) in Chilean hakes, 15% (CI: 0.07–0.26) in snoeks, and 1.7% (CI: 0–0.089) in sea breams. Meanwhile, prevalence of anisakid larvae in internal organs showed highest values for peritoneum (100% and 83.3%) for snoeks and Chilean hakes, respectively, for liver (96.7%) and gonads (86.6%) in Chilean hakes, and for intestine (98.3%) in snoeks. Molecular analysis of collected anisakid L3 unveiled presence of two potentially zoonotic nematode species, i.e.,
Pseudoterranova cattani
and
Anisakis pegreffii
.
P. cattani
was found in Chilean hakes and snoeks being the first molecular host species report for Chilean snoeks. Besides,
A. pegreffii
was also identified in these species being the first molecular report on this regard. These findings are relevant for better understanding of epidemiology of anisakiasis in Chilean coasts and for public health issues considering potential risk of human population due to its culinary preferences in eating raw fish.
Ticks are important parasites from economic and public health points of view because of their ability to reduce farm animals’ productivity and transmit zoonotic diseases. We conducted this ...cross-sectional study between January and March 2016 and between March and April 2017 to identify tick species in West Darfur, Al-Jazeera, and the River Nile states in the Sudan and to investigate whether these ticks carry
Rickettsia
spp. and Crimean-Congo hemorrhagic fever (CCHF) virus. In total, 1593 ticks were collected from 207 animals and identified based on morphology or 16S rRNA gene and tested for
Rickettsia
spp. and CCHF virus either individually or as pools containing 2 to 10 pooled ticks using molecular methods. Overall, 14 tick species belonging to three genera, namely
Amblyomma
,
Hyalomma
, and
Rhipicephalus
, were identified.
Hyalomma anatolicum
and
Rhipicephalus evertsi evertsi
were the most frequent ticks. A total of 561 tests comprised of individual or pooled ticks were conducted and 13.7% (77/561) were positive for
Rickettsia
spp. which were mostly
Rickettsia aeschlimannii
and
R
.
africae
. The highest positivity was noticed among
H
.
rufipes
collected from cattle and camels in West Darfur. However, none of the screened
Hyalomma
ticks harbored CCHF viral RNA. These findings suggest that there might be a risk of zoonotic transmission of
Rickettsia
spp. by ticks but zoonotic transmission of CCHF virus is apparently doubtful. An in-depth and a country-wide epidemiological study is needed to better understand the dynamic of
Rickettsia
spp. and CCHF virus in the Sudan.
Blastocystis
is a parasite with a worldwide distribution and a varying prevalence in different countries. The pleomorphic nature of the protozoon and the lack of understanding a possible pathogenesis ...have led to confusion regarding its clinical significance. The aim of the study was to shed light on clinical characteristics of pediatric patients in Swiss children with a positive stool sample for
Blastocystis
, in order to provide recommendations for a practical approach for the clinician to know whom, when, and how to test. This is a retrospective study of pediatric patients, whose stool has been tested positive for
Blastocystis
in the last 10 years in northern Switzerland. A total of 4047 stool samples, belonging to 1887 different patients, were analyzed; 240 stool samples (of 160 patients) were tested positive for
Blastocystis
. On average, 2.2 (CI 1.98–2.35) stool samples per patient were analyzed, of which 1.48 (CI 1.36–1.61) were positive for
Blastocystis
. In 63% abdominal pain was the leading symptom, while in 17.5% it was an accidental finding without symptoms. There was a high significance in correlation of abdominal pain and chronicity (
p
< 0.0001) but none in diarrhea (
p
= 0.082) nor nausea/vomiting or other symptoms and chronicity. Followed by
Entamoeba coli
(8%), 26.3% of the patients with
Blastocystis
had a co-infection with another parasite, mostly
Endolimax nana
(13%).
Conclusion
: Carriage of
Blastocystis
is common; therefore, only children/teenagers at risk for a symptomatic
Blastocystis
infection should be tested. There is a good correlation between
Blastocystis
and chronic abdominal pain. Children with abdominal symptoms persisting over 4 weeks should have two different stool samples analyzed. No screening after travels/immigration is recommended.
What is Known:
•
Blastocystis has a worldwide distribution.
•
The clinical significance is unclear.
What is New:
•
Based on retrospective data, we recommend to only test children/teenagers with chronic abdominal pain for Blastocystis.
•
Two different stool samples should be examined by microscopy; serological investigations are not warranted.
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