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Neonatal SARS-CoV-2 Infection: Practical Tips -
Acinetobacter baumannii: An Ancient Commensal with Weapons of a Pathogen -
Isolation and Characterization of Nocardiae Associated with Foaming Coastal Marine Waters -
Microscopic Observation of SARS-Like Particles in RT-qPCR SARS-CoV-2 Positive Sewage Samples -
Avian Influenza in Wild Birds and Poultry: Dissemination Pathways, Monitoring Methods, and Virus Ecology
Journal Description
Pathogens
Pathogens
is an international, peer-reviewed, open access journal of pathogens and pathogen-host interactions published monthly online by MDPI.
- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- High Visibility: indexed within Scopus, SCIE (Web of Science), PubMed, PMC, Embase, AGRICOLA, CaPlus / SciFinder, and many other databases.
- Journal Rank: JCR - Q2 (Microbiology)
- Rapid Publication: manuscripts are peer-reviewed and a first decision provided to authors approximately 14.3 days after submission; acceptance to publication is undertaken in 2.9 days (median values for papers published in this journal in the first half of 2021).
- Recognition of Reviewers: reviewers who provide timely, thorough peer-review reports receive vouchers entitling them to a discount on the APC of their next publication in any MDPI journal, in appreciation of the work done.
- Companion journals for Pathogens include: Parasitologia, Bacteria and Zoonoses.
Impact Factor:
3.492 (2020)
;
5-Year Impact Factor:
4.066 (2020)
Latest Articles
Efficacy of Needle-Less Intradermal Vaccination against Porcine Epidemic Diarrhea Virus
Pathogens 2021, 10(9), 1115; https://doi.org/10.3390/pathogens10091115 - 31 Aug 2021
Abstract
To prevent diarrhea in suckling piglets infected by porcine epidemic diarrhea virus (PEDV), porcine epidemic diarrhea (PED) vaccines are administered mainly through intramuscular (IM) or oral routes. We found that growing pigs vaccinated with an inactivated PEDV vaccine via the intradermal (ID) route
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To prevent diarrhea in suckling piglets infected by porcine epidemic diarrhea virus (PEDV), porcine epidemic diarrhea (PED) vaccines are administered mainly through intramuscular (IM) or oral routes. We found that growing pigs vaccinated with an inactivated PEDV vaccine via the intradermal (ID) route had higher neutralizing antibody titers and cytokine (IFN-γ, IL-4, and IL-10) levels than non-vaccinated pigs. In addition, suckling piglets acquired lactogenic immunity from pregnant sows inoculated with an ID PED vaccine. We evaluated the efficacy of vaccination via this route, along with subsequent protection against virulent PEDV. At six days post-challenge, the survival rate of suckling piglets exposed to virulent PEDV was 70% for the ID group and 0% for the mock group (no vaccine). At necropsy, villi length in the duodenum and ileum of piglets with lactogenic immunity provided by ID-vaccinated sows proved to be significant (p < 0.05) when compared with those in piglets from mock group sows. Thus, vaccination using an inactivated PED vaccine via the ID route provides partial protection against infection by virulent PEDV.
Full article
(This article belongs to the Special Issue Porcine Epidemic Diarrhea Virus)
Open AccessArticle
Protozoan and Microbial Pathogens of House Cats in the Province of Tekirdag in Western Turkey
Pathogens 2021, 10(9), 1114; https://doi.org/10.3390/pathogens10091114 - 31 Aug 2021
Abstract
Domestic felines' re-emerging infectious and neglected zoonotic diseases are a significant focus of global "One Health" efforts. This study aimed to rapidly diagnose 14 pathogens, including zoonoses by using PCR primers in 167 client-owned symptomatic cats, routinely accepted to the Veterinary Clinics of
[...] Read more.
Domestic felines' re-emerging infectious and neglected zoonotic diseases are a significant focus of global "One Health" efforts. This study aimed to rapidly diagnose 14 pathogens, including zoonoses by using PCR primers in 167 client-owned symptomatic cats, routinely accepted to the Veterinary Clinics of Tekirdag. The prevalence of pathogens investigated were as follows: Babesia canis canis (24%), Babesia microti (2.4%), Hepatozoon felis (10.8%), Cytauxzoon felis (6.6%), Bartonella henselae (40.1%), Anaplasma platys (30.5%), Anaplasma phagocytophilum (7.2%), Rickettsia felis (26.3%), Borrelia burgdorferi (21%), and hemotropic Mycoplasma sp. (11.4%). There was a significant difference between the prevalence of the pathogens (?2 = 152.26, df = 9, p < 0.001). There was also a statistical difference between the gender of the cats in terms of the prevalence of all pathogens considered together (?2 = 4.80, df = 1, p = 0.028), where the female cats showed a higher prevalence. This was not the case for the different age groups (?2 = 2.92, df = 1, p=0.088). The lowest infection was observed for B. microti (p < 0.001), while the highest infection was observed for B. henselae (p < 0.01). Leishmania donovani, Plasmodium spp., Ehrlichia chaffeensis, and Neoehrlichia mikurensis PCR test results were negative in all samples. In conclusion, house cats of Tekirdag are apparently highly susceptible to some neglected zoonoses important for "One Health," and their prevalence in the region is most probably underestimated. Hence, applying PCR tests to assist fast clinic diagnosis in routine, may be an efficient option to protect the public as well as the cats from severe diseases.
Full article
Open AccessReview
Nasopharyngeal Carcinoma: The Role of the EGFR in Epstein–Barr Virus Infection
Pathogens 2021, 10(9), 1113; https://doi.org/10.3390/pathogens10091113 - 31 Aug 2021
Abstract
Epstein–Barr virus (EBV), a type 4 γ herpes virus, is recognized as a causative agent in nasopharyngeal carcinoma (NPC). Incidence of EBV-positive NPC have grown in recent decades along with worse outcomes compared with their EBV-negative counterparts. Latent membrane protein 1 (LMP1), encoded
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Epstein–Barr virus (EBV), a type 4 γ herpes virus, is recognized as a causative agent in nasopharyngeal carcinoma (NPC). Incidence of EBV-positive NPC have grown in recent decades along with worse outcomes compared with their EBV-negative counterparts. Latent membrane protein 1 (LMP1), encoded by EBV, induces NPC progression. The epidermal growth factor receptor (EGFR), a member of the ErbB family of receptor tyrosine kinases (RTK), is a driver of tumorigenesis, including for NPC. Little data exist on the relationship between EGFR and EBV-induced NPC. In our initial review, we found that LMP1 promoted the expression of EGFR in NPC in two main ways: the NF-κB pathway and STAT3 activation. On the other hand, EGFR also enhances EBV infection in NPC cells. Moreover, activation of EGFR signalling affects NPC cell proliferation, cell cycle progression, angiogenesis, invasion, and metastasis. Since EGFR promotes tumorigenesis and progression by downstream signalling pathways, causing poor outcomes in NPC patients, EGFR-targeted drugs could be considered a newly developed anti-tumor drug. Here, we summarize the major studies on EBV, EGFR, and LMP1-regulatory EGFR expression and nucleus location in NPC and discuss the clinical efficacy of EGFR-targeted agents in locally advanced NPC (LA NPC) and recurrent or metastatic NPC (R/M NPC) patients.
Full article
(This article belongs to the Special Issue Epstein-Barr Virus (EBV) and Nasopharyngeal Carcinoma (NPC): Pathogenesis, Viral-Host Interaction and Therapeutic Strategies)
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Open AccessCase Report
“Chiclero’s Ulcer” Due to Leishmania mexicana in Travelers Returning from Central America: A Case Report and Review of the Literature
Pathogens 2021, 10(9), 1112; https://doi.org/10.3390/pathogens10091112 - 31 Aug 2021
Abstract
Cutaneous leishmaniasis (CL) due to a New World species of Leishmania is increasingly seen among returning international travelers, and most cases arise from travel to Mexico, Central and South America. We described a case of CL in a women presenting a nonhealing ulceration
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Cutaneous leishmaniasis (CL) due to a New World species of Leishmania is increasingly seen among returning international travelers, and most cases arise from travel to Mexico, Central and South America. We described a case of CL in a women presenting a nonhealing ulceration under her right ear with slight increase of size of the left parotid gland under the skin lesion, evolving for 4 months. In her history of travel, she reported a ten-day stay in Mexico during the Christmas vacation in the Yucatan region with only half a day walking in the tropical forest. Diagnosis of CL due to Leishmania mexicana was done via PCR detection and sequencing from swab sampling of the lesion. The patient recovered without antiparasitic treatment. Clinicians should consider diagnosing Chiclero’s ulcer in patients returning from endemic areas such as Central America and Texas who present with chronic ulceration. A noninvasive sampling is sufficient for the PCR-based diagnosis of this disease.
Full article
(This article belongs to the Special Issue Epidemiology of Parasitic Zoonoses)
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Open AccessArticle
Development of Human Toxo IgG ELISA Kit, and False-Positivity of Latex Agglutination Test for the Diagnosis of Toxoplasmosis
Pathogens 2021, 10(9), 1111; https://doi.org/10.3390/pathogens10091111 - 31 Aug 2021
Abstract
Toxoplasma gondii is an intracellular zoonotic parasite that causes infection in a wide range of warm-blooded animals and humans. The main aim of this studywas to assess the diagnostic value of the recombinant SAG1 antigen (rSAG1) for T. gondii-IgG screening through the
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Toxoplasma gondii is an intracellular zoonotic parasite that causes infection in a wide range of warm-blooded animals and humans. The main aim of this studywas to assess the diagnostic value of the recombinant SAG1 antigen (rSAG1) for T. gondii-IgG screening through the Human Toxo IgG ELISA Kit (K). The rSAG1 was expressed in E. coli (DE3), and it was purified through metal-affinity chromatography. The rSAG1 was confirmed by immunoblotting, and it had a band on 35 kDa.Total of 400 human sera were tested by LAT and K. One hundred and twenty-two (30.5%) sera were found positive by LAT and eighty-nine (22.25%) sera were found positive by K.Out of 400 samples, 80 were selected to evaluate the performance of K through commercial Toxoplasma gondii IgG ELISA Kit (C). Out of 80 human sera, 55 (68.75%) were found positive, 25 (31.25%) were found negative by K and C, respectively. The cut-off value for K was 0.398 and it was calculated through the receiver operator characteristic curve. The ELISA plates were coated at optimized concentration of rSAG1 = 0.125 µg/mL, and the test was performed by diluting the sera at 1:50. The sensitivity and specificity of K were observed to be 98.5% and 100%, respectively. The six sera (K-L+were found positive through LAT and these human sera were later evaluated by Western blot analysis. These sera did not produce a band equivalent to 35 kDa on WB analysis thus, LAT produced false-positive results
Full article
(This article belongs to the Special Issue Toxoplasma)
Open AccessArticle
Antibiogram Profile of Acinetobacterbaumannii Recovered from Selected Freshwater Resources in the Eastern Cape Province, South Africa
Pathogens 2021, 10(9), 1110; https://doi.org/10.3390/pathogens10091110 - 31 Aug 2021
Abstract
Acinetobacter species have been found in a variety of environments, including soil, food, plants, hospital environments and water. Acinetobacter baumannii is an opportunistic and emerging waterborne pathogen. It has been implicated in several nosocomial infections that demonstrate resistance to commonly administered antibiotics. We
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Acinetobacter species have been found in a variety of environments, including soil, food, plants, hospital environments and water. Acinetobacter baumannii is an opportunistic and emerging waterborne pathogen. It has been implicated in several nosocomial infections that demonstrate resistance to commonly administered antibiotics. We investigated phenotypic antibiotic resistance (PAR) and relevant antibiotic resistance genes (ARGs) in A. baumannii isolated from three freshwater resources in the Eastern Cape Province, South Africa; A. baumannii (410) was confirmed by the recA and gyrB genes of 844 suspected Acinetobacter species in the water samples. The PAR of the confirmed isolates was assessed using a panel of 11 antibiotics by the disc diffusion method, while ARGs were investigated in isolates exhibiting PAR. The A. baumannii isolates were resistant to piperacillin-tazobactam (11.2%), ceftazidime (12%), cefotaxime (18.8%), cefepime (8.8%), imipenem (2.7%), meropenem (4.15%), amikacin (2.4%), gentamicin (8.8%), tetracycline (16.8%), ciprofloxacin (11%) and trimethoprim/sulfamethoxazole (20.5%). For multidrug resistance (MDR), two isolates were resistant to all antibiotics and 28 isolates were resistant to imipenem and meropenem. Moreover, β-lactamases blaTEM (64.4%) and blaOXA-51 (28.70%) as well as sulphonamides sul1 (37.1%) and sul2 (49.4%) were common ARGs. Overall, PAR and ARGs had positive correlations (r) in all rivers. Detection of MDR-A. baumannii in freshwater resources could be linked to possible wastewater discharge from the nearby animal farms, indicating potential implications for public health.
Full article
(This article belongs to the Section Bacterial Pathogens)
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Open AccessArticle
Clinico-Genomic Analysis Reveals Mutations Associated with COVID-19 Disease Severity: Possible Modulation by RNA Structure
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, , , , , , , , , , , , , , , , , , , , and
Pathogens 2021, 10(9), 1109; https://doi.org/10.3390/pathogens10091109 - 31 Aug 2021
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) manifests a broad spectrum of clinical presentations, varying in severity from asymptomatic to mortality. As the viral infection spread, it evolved and developed into many variants of concern. Understanding the impact of mutations in the SARS-CoV-2
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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) manifests a broad spectrum of clinical presentations, varying in severity from asymptomatic to mortality. As the viral infection spread, it evolved and developed into many variants of concern. Understanding the impact of mutations in the SARS-CoV-2 genome on the clinical phenotype and associated co-morbidities is important for treatment and preventionas the pandemic progresses. Based on the mild, moderate, and severe clinical phenotypes, we analyzed the possible association between both, the clinical sub-phenotypes and genomic mutations with respect to the severity and outcome of the patients. We found a significant association between the requirement of respiratory support and co-morbidities. We also identified six SARS-CoV-2 genome mutations that were significantly correlated with severity and mortality in our cohort. We examined structural alterations at the RNA and protein levels as a result of three of these mutations: A26194T, T28854T, and C25611A, present in the Orf3a and N protein. The RNA secondary structure change due to the above mutations can be one of the modulators of the disease outcome. Our findings highlight the importance of integrative analysis in which clinical and genetic components of the disease are co-analyzed. In combination with genomic surveillance, the clinical outcome-associated mutations could help identify individuals for priority medical support.
Full article
(This article belongs to the Special Issue SARS-CoV-2 Infection and COVID-19 Disease)
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Open AccessReview
An Overview of the Pathogenesis, Transmission, Diagnosis, and Management of Endemic Human Coronaviruses: A Reflection on the Past and Present Episodes and Possible Future Outbreaks
Pathogens 2021, 10(9), 1108; https://doi.org/10.3390/pathogens10091108 - 30 Aug 2021
Abstract
The outbreak of the 2019 coronavirus pandemic caught the world by surprise in late 2019 and has held it hostage for months with an increasing number of infections and deaths. Although coronavirus was first discovered in the 1960s and was known to cause
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The outbreak of the 2019 coronavirus pandemic caught the world by surprise in late 2019 and has held it hostage for months with an increasing number of infections and deaths. Although coronavirus was first discovered in the 1960s and was known to cause respiratory infection in humans, no information was available about the epidemic pattern of the virus until the past two decades. This review addresses the pathogenesis, transmission dynamics, diagnosis, management strategies, the pattern of the past and present events, and the possibility of future outbreaks of the endemic human coronaviruses. Several studies have described bats as presumptive natural reservoirs of coronaviruses. In essence, the identification of a diverse group of similar SARS coronaviruses in bats suggests the possibility of a future epidemic due to severe acute respiratory syndrome (SARS-like) coronaviruses originating from different reservoir hosts. The study also identified a lack of vaccines to prevent human coronavirus infections in humans in the past, however, the recent breakthrough in vaccine discovery and approval for emergency use for the treatment of Severe Acute Respiratory Syndrome Coronavirus 2 is commendable. The high rates of genomic substitution and recombination due to errors in RNA replication and the potential for independent species crossing suggest the chances of an entirely new strain evolving. Therefore, rapid research efforts should be deployed for vaccination to combat the COVID-19 pandemic and prevent a possible future outbreak. More sensitization and enlightenment on the need to adopt good personal hygiene practices, social distancing, and scientific evaluation of existing medications with promising antiviral effects against SARS-CoV-2 is required. In addition, intensive investigations to unravel and validate the possible reservoirs, the intermediate host, as well as insight into the ability of the virus to break the species barrier are needed to prevent future viral spillover and possible outbreaks.
Full article
(This article belongs to the Special Issue Coronaviruses and Other Human Respiratory Viruses from “Regular” Circulating Agents to Emerging Pathogens and the One Health Concept)
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Open AccessArticle
Molecular Investigation of Zoonotic Intestinal Protozoa in Pet Dogs and Cats in Yunnan Province, Southwestern China
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, , , , , , , and
Pathogens 2021, 10(9), 1107; https://doi.org/10.3390/pathogens10091107 - 30 Aug 2021
Abstract
Giardia duodenalis, Enterocytozoon bieneusi and Cryptosporidium spp. are common enteric pathogens that reside in the intestines of humans and animals. These pathogens have a broad host range and worldwide distribution, but are mostly known for their ability to cause diarrhea. However, very
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Giardia duodenalis, Enterocytozoon bieneusi and Cryptosporidium spp. are common enteric pathogens that reside in the intestines of humans and animals. These pathogens have a broad host range and worldwide distribution, but are mostly known for their ability to cause diarrhea. However, very limited information on prevalence and genotypes of G. duodenalis, E. bieneusi and Cryptosporidium spp. in pet dogs and cats are available in China. In the present study, a total of 433 fecal samples were collected from 262 pet dogs and 171 pet cats in Yunnan province, southwestern China, and the prevalence and the genotypes of G. duodenalis, E. bieneusi and Cryptosporidium spp. were investigated by nested PCR amplification and DNA sequencing. The prevalence of G. duodenalis, E. bieneusi and Cryptosporidium spp. was 13.7% (36/262), 8.0% (21/262), and 4.6% (12/262) in dogs, and 1.2% (2/171), 0.6% (4/171) and 2.3% (1/171) in cats, respectively. The different living conditions of dogs is a risk factor that is related with the prevalence of G. duodenalis and E. bieneusi (P < 0.05). However, there were no statistically significant difference in prevalence of three pathogens in cats. DNA sequencing and analyses showed that four E. bieneusi genotypes (PtEb IX, CD9, DgEb I and DgEb II), one Cryptosporidium spp. (C. canis) and two G. duodenalis assemblages (C and D) were identified in dogs; two E. bieneusi genotypes (Type IV and CtEb I), one Cryptosporidium spp. (C. felis) and one G. duodenalis assemblage (F) were identified in cats. Three novel E. bieneusi genotypes (DgEb I, DgEb II and CtEb I) were identified, and the human-pathogenic genotypes/species Type IV C. canis and C. felis were also observed in this study, indicating a potential zoonotic threat of pet dogs and cats. Our results revealed the prevalence and genetic diversity of G. duodenalis, E. bieneusi and Cryptosporidium spp. infection in pet dogs and cats in Yunnan province, southwestern China, and suggested the potential threat of pet dogs and cats to public health.
Full article
(This article belongs to the Special Issue Diagnosis, Epidemiology and Transmission Dynamics of Cryptosporidium spp. and Giardia duodenalis)
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Open AccessArticle
Discrete Survival Model Analysis of Plasmodium falciparum Response to Artemisinin-Based Combination Therapies among Children in Regions of Varying Malaria Transmission in Cameroon
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, , , , , and
Pathogens 2021, 10(9), 1106; https://doi.org/10.3390/pathogens10091106 - 30 Aug 2021
Abstract
The need to monitor changes in parasite clearance following treatment with artemisinin-based combination therapies (ACTs) is important in the containment of drug resistance. This study aimed to model Plasmodium falciparum response to ACTs among children in two different transmission settings (Mutengene and Garoua)
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The need to monitor changes in parasite clearance following treatment with artemisinin-based combination therapies (ACTs) is important in the containment of drug resistance. This study aimed to model Plasmodium falciparum response to ACTs among children in two different transmission settings (Mutengene and Garoua) in Cameroon. Using the step function, a discrete-time survival model was fitted with all the covariates included that might play a role in parasite clearance. The probability of clearing parasites within 24 h following treatment was 21.6% and 70.3% for younger children aged 6 to 59 months and 29.3% and 59.8% for older children aged 60 to 120 months in Mutengene and Garoua, respectively. After two days of treatment, the conditional probability of clearing parasites given that they were not cleared on day 1 was 76.7% and 96.6% for children aged 6–59 months and 83.1% and 93.5% for children aged 60–120 months in Mutengene and Garoua, respectively. The model demonstrated that the ecological setting, age group and pretreatment serum levels of creatinine and alanine aminotransferase were the main factors that significantly influenced parasite clearance in vivo after administration of ACTs (p < 0.05). The findings highlight the need for further investigations on host differential response to ACTs in current practice.
Full article
(This article belongs to the Special Issue Advances in Human Pathogens Infections)
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Asymptomatic COVID-19 Individuals Tend to Establish Relatively Balanced Innate and Adaptive Immune Responses
Pathogens 2021, 10(9), 1105; https://doi.org/10.3390/pathogens10091105 - 30 Aug 2021
Abstract
The sharp increase in the proportion of asymptomatic cases and the potential risk of virus transmission have greatly increased the difficulty of controlling the COVID-19 pandemic. The individual immune response is closely associated with clinical outcomes and pathogenic mechanisms of COVID-19. However, the
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The sharp increase in the proportion of asymptomatic cases and the potential risk of virus transmission have greatly increased the difficulty of controlling the COVID-19 pandemic. The individual immune response is closely associated with clinical outcomes and pathogenic mechanisms of COVID-19. However, the clinical characteristics and immunophenotyping features of immune cells of asymptomatic individuals remain somewhat mysterious. To better understand and predict the disease state and progress, we performed a comprehensive analysis of clinical data, laboratory indexes and immunophenotyping features in 41 patients with SARS-CoV-2 (including 24 asymptomatic cases and 17 symptomatic individuals). Firstly, from the perspective of demographic characteristics, the rate of asymptomatic infection was significantly higher in those with younger age. Secondly, the laboratory test results showed that some indexes, such as CRP (acute phase reaction protein), D-Dimer and fibrinogen (the marker for coagulation) were lower in the asymptomatic group. Finally, symptomatic individuals were prone to establishing a non-protective immune phenotype by abnormally decreasing the lymphocyte count and percentage, abnormally increasing the Th17 percentage and decreasing Treg percentage, which therefore cause an increase in the neutrophil/lymphocyte ratio (NLR), monocytes/lymphocytes ratio (MLR) and Th17/Treg ratio. On the other hand, asymptomatic individuals tended to establish a more effective and protective immune phenotype by maintaining a normal level of lymphocyte count and percentage and a high level of NK cells. At the same time, asymptomatic individuals can establish a relatively balanced immune response through maintaining a low level of monocytes, a relatively low level of Th17 and high level of Treg, which therefore lead to a decrease in MNKR and Th17/Treg ratio and finally the avoidance of excessive inflammatory responses. This may be one of the reasons for their asymptomatic states. This study is helpful to reveal the immunological characteristics of asymptomatic individuals, understand immune pathogenesis of COVID-19 and predict clinical outcomes more precisely. However, owing to small sample sizes, a future study with larger sample size is still warranted.
Full article
(This article belongs to the Special Issue Immune Responses to Emerging Viruses)
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Open AccessCase Report
First Autochthonous Infection of a Cat with Dirofilaria immitis in Austria
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Pathogens 2021, 10(9), 1104; https://doi.org/10.3390/pathogens10091104 - 30 Aug 2021
Abstract
This case report is about a seven-year-old male neutered European Shorthair cat infected by Dirofilaria immitis as the first reported autochthonous Dirofilaria immitis infection in Austria. There was no history of periods abroad. Echocardiography showed suspected D. immitis in the right cardiac chamber
[...] Read more.
This case report is about a seven-year-old male neutered European Shorthair cat infected by Dirofilaria immitis as the first reported autochthonous Dirofilaria immitis infection in Austria. There was no history of periods abroad. Echocardiography showed suspected D. immitis in the right cardiac chamber with increased pulmonary pressure and ascites. Surgical removal of the heartworms was performed. Twenty adult heartworms were removed by transvenous jugular approach under general anesthesia and stored in 4% formalin. Five out of 20 specimens were examined via light and stereomicroscopy and feline heartworm infection was confirmed. Amplification of a 203 bp or 724 bp fragment of the cytochrome c oxidase subunit I gene was unsuccessful. After surgery the cat developed acute renal failure but recovered quickly. One year later, the cat underwent a control examination including echocardiography and blood work. There were no more D. immitis detectable at echocardiography. Lung pressure was mildly increased. Complete blood count and creatinine were unremarkable. The Knott’s test and Dirofilaria-Antigen-test produced negative results. The cat did not show any clinical signs during the follow-up period. The aim of this case report is to highlight the growing risk of acquiring infection with D. immitis not only for Austrian dogs, but also for cats. This case report represents the first report of autochthonous D. immitis infection in Austria. Moreover, even if the prognosis in cats with caval syndrome due to feline heartworm disease is guarded to poor, surgical removal of the filariae can be a successful treatment option.
Full article
(This article belongs to the Special Issue Parasites of the Third Millennium)
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Open AccessArticle
Characteristics of Chlamydia suis Ocular Infection in Pigs
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, , , , , , , , , , and
Pathogens 2021, 10(9), 1103; https://doi.org/10.3390/pathogens10091103 - 29 Aug 2021
Abstract
Chlamydia (C.) suis can often be isolated from conjunctival swab specimens from pigs with conjunctivitis or keratoconjunctivitis. In the field, it is assumed to be a multifactorial disease triggered by immunosuppressing factors. This is the first experimental study to provoke clinical
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Chlamydia (C.) suis can often be isolated from conjunctival swab specimens from pigs with conjunctivitis or keratoconjunctivitis. In the field, it is assumed to be a multifactorial disease triggered by immunosuppressing factors. This is the first experimental study to provoke clinical signs of conjunctivitis in pigs after C. suis primary mono-infection. Five six-week-old male piglets, free of ocular chlamydia shedding and seronegative for Chlamydia, were conjunctivally infected with the C. suis-type strain S45 (1 × 109 inclusion forming units), while four piglets served as negative controls. The infection group developed clinical signs of conjunctivitis with a peak in the first week post-infection. Immunohistochemical evaluation revealed the presence of Chlamydia not only in the conjunctival epithelium, but also in the enlarged lacrimal glands, lungs, and intestine. No circulating antibodies could be detected during the whole study period of three weeks, although three different test systems were applied as follows: the complement fixation test, MOMP-based Chlamydiaceae ELISA, and PmpC-based C. suis ELISA. Meanwhile, high numbers of IFN-γ-producing lymphocytes within PBMC were seen after C. suis re-stimulation 14 days post-infection. Hence, these data suggest that entry via the eye may not elicit immunological responses comparable to other routes of chlamydial infections.
Full article
(This article belongs to the Special Issue Animal Chlamydiae: A Concern for Human and Veterinary Medicine)
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Open AccessArticle
Genomic Variability of Canine Parvoviruses from a Selected Population of Dogs and Cats in Sri Lanka
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, , , , , , and
Pathogens 2021, 10(9), 1102; https://doi.org/10.3390/pathogens10091102 - 29 Aug 2021
Abstract
The aim of the study was to identify canine parvovirus type 2 (CPV-2) subtypes circulating among a selected population of domestic dogs and cats in Sri Lanka and to investigate the evolutionary patterns among Sri Lankan viruses in the context of contemporary global
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The aim of the study was to identify canine parvovirus type 2 (CPV-2) subtypes circulating among a selected population of domestic dogs and cats in Sri Lanka and to investigate the evolutionary patterns among Sri Lankan viruses in the context of contemporary global CPV-2 sequences. Altogether, 40/61 (65.6%) samples tested were positive for CPV-2 DNA, including 31/48 (64.6%) dogs and 9/13 (69%) cats. All three subtypes (CPV-2a, CPV-2b and CPV-2c) were detected, with CPV-2a being most common. International median joining haplotype network of 291 CPV-2 sequences suggested that there was little barrier for CPV-2 moving between different geographical regions worldwide, including Sri Lanka, and that there was no correlation between the genetic structure within the molecular network and the decade of sample collection. By contrast, there was correlation between CPV-2 subtype and genetic structure, both within the international network and within the network built from 31 Sri Lankan CPV-2 sequences only. The structure within the latter was not correlated with the location of the veterinary clinic where the samples were submitted, the age or species of the host. Altogether, we have shown that there is considerable variability of CPV-2 genotypes circulating in Sri Lanka, which is likely driven by both local evolution and introduction from other countries. The similarity of CPV-2 obtained from cats and dogs suggests that cats may play a role in the epidemiology of CPV-2 in Sri Lanka.
Full article
(This article belongs to the Special Issue Epidemiology, Surveillance and Control of Infectious Diseases)
Open AccessArticle
Examining the Relationship between Toxoplasma gondii and Seropositivity and Serointensity and Depression in Adults from the United Kingdom and the United States: A Cross-Sectional Study
Pathogens 2021, 10(9), 1101; https://doi.org/10.3390/pathogens10091101 - 29 Aug 2021
Abstract
Infecting approximately one-third of the world’s population, the neurotropic protozoan Toxoplasma gondii has been associated with cognition and several neuropsychiatric diseases including schizophrenia and bipolar disorder. Findings have been mixed, however, about the relationship between Toxoplasma gondii and depression, with some studies reporting
[...] Read more.
Infecting approximately one-third of the world’s population, the neurotropic protozoan Toxoplasma gondii has been associated with cognition and several neuropsychiatric diseases including schizophrenia and bipolar disorder. Findings have been mixed, however, about the relationship between Toxoplasma gondii and depression, with some studies reporting positive associations and others finding no associations. To further investigate the association between Toxoplasma gondii and depression, we used data from the UK Biobank and the National Health and Examination Survey (NHANES). Results from adjusted multiple-regression modeling showed no significant associations between Toxoplasma gondii and depression in either the UK Biobank or NHANES datasets. Further, we found no significant interactions between Toxoplasma gondii and age, sex, educational attainment, and income in either dataset that affected the association between Toxoplasma gondii and depression. These results from two community-based datasets suggest that in these samples, Toxoplasma gondii is not associated with depression. Differences between our findings and other findings showing an association between Toxoplasma gondii and depression could be due to several factors including differences in socioeconomic variables, differences in Toxoplasma gondii strain, and use of different covariates in statistical modeling.
Full article
(This article belongs to the Special Issue Effects of Toxoplasma gondii Infection on Human Behaviour)
Open AccessArticle
A Rapid Method for Performing a Multivariate Optimization of Phage Production Using the RCCD Approach
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, , , , , , , and
Pathogens 2021, 10(9), 1100; https://doi.org/10.3390/pathogens10091100 - 29 Aug 2021
Abstract
Bacteriophages can be used in various applications, from the classical approach as substitutes for antibiotics (phage therapy) to new biotechnological uses, i.e., as a protein delivery vehicle, a diagnostic tool for specific strains of bacteria (phage typing), or environmental bioremediation. The demand for
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Bacteriophages can be used in various applications, from the classical approach as substitutes for antibiotics (phage therapy) to new biotechnological uses, i.e., as a protein delivery vehicle, a diagnostic tool for specific strains of bacteria (phage typing), or environmental bioremediation. The demand for bacteriophage production increases daily, and studies that improve these production processes are necessary. This study evaluated the production of a T4-like bacteriophage vB_EcoM-UFV09 (an E. coli-infecting phage with high potential for reducing environmental biofilms) in seven types of culture media (Luria–Bertani broth and the M9 minimal medium with six different carbon sources) employing four cultivation variables (temperature, incubation time, agitation, and multiplicity of infection). For this purpose, the rotatable central composite design (RCCD) methodology was used, combining and comparing all parameters to determine the ideal conditions for starting to scale up the production process. We used the RCCD to set up the experimental design by combining the cultivation parameters in a specific and systematic way. Despite the high number of conditions evaluated, the results showed that when specific conditions were utilized, viral production was effective even when using a minimal medium, such as M9/glucose, which is less expensive and can significantly reduce costs during large-scale phage production.
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(This article belongs to the Special Issue Viruses of Microbes: From Basics to Biotechnological Application)
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Helicobacter pylori-Induced Inflammation: Possible Factors Modulating the Risk of Gastric Cancer
Pathogens 2021, 10(9), 1099; https://doi.org/10.3390/pathogens10091099 - 29 Aug 2021
Abstract
Chronic inflammation and long-term tissue injury are related to many malignancies, including gastric cancer (GC). Helicobacter pylori (H. pylori), classified as a class I carcinogen, induces chronic superficial gastritis followed by gastric carcinogenesis. Despite a high prevalence of H. pylori infection,
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Chronic inflammation and long-term tissue injury are related to many malignancies, including gastric cancer (GC). Helicobacter pylori (H. pylori), classified as a class I carcinogen, induces chronic superficial gastritis followed by gastric carcinogenesis. Despite a high prevalence of H. pylori infection, only about 1–3% of people infected with this bacterium develop GC worldwide. Furthermore, the development of chronic gastritis in some, but not all, H. pylori-infected subjects remains unexplained. These conflicting findings indicate that clinical outcomes of aggressive inflammation (atrophic gastritis) to gastric carcinogenesis are influenced by several other factors (in addition to H. pylori infection), such as gut microbiota, co-existence of intestinal helminths, dietary habits, and host genetic factors. This review has five goals: (1) to assess our current understanding of the process of H. pylori-triggered inflammation and gastric precursor lesions; (2) to present a hypothesis on risk modulation by the gut microbiota and infestation with intestinal helminths; (3) to identify the dietary behavior of the people at risk of GC; (4) to check the inflammation-related genetic polymorphisms and role of exosomes together with other factors as initiators of precancerous lesions and gastric carcinoma; and (5) finally, to conclude and suggest a new direction for future research.
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(This article belongs to the Special Issue Inflammation and Gastrointestinal/Hepatobiliary Cancers)
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Approaching In Vivo Models of Pneumococcus–Host Interaction: Insights into Surface Proteins, Capsule Production, and Extracellular Vesicles
Pathogens 2021, 10(9), 1098; https://doi.org/10.3390/pathogens10091098 - 28 Aug 2021
Abstract
Infections caused by the Gram-positive bacterium Streptococcus pneumoniae have become a major health problem worldwide because of their high morbidity and mortality rates, especially in developing countries. This microorganism colonizes the human upper respiratory tract and becomes pathogenic under certain circumstances, which are
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Infections caused by the Gram-positive bacterium Streptococcus pneumoniae have become a major health problem worldwide because of their high morbidity and mortality rates, especially in developing countries. This microorganism colonizes the human upper respiratory tract and becomes pathogenic under certain circumstances, which are not well known. In the interaction with the host, bacterial surface structures and proteins play major roles. To gain knowledge into gradual changes and adaptive mechanisms that this pathogen undergoes from when it enters the host, we mimicked several in vivo situations representing interaction with epithelial and macrophage cells, as well as a condition of presence in blood. Then, we analyzed, in four pneumococcal strains, two major surface structures, the capsule and extracellular vesicles produced by the pneumococci, as well as surface proteins by proteomics, using the “shaving” approach, followed by LC-MS/MS. We found important differences in both surface ultrastructures and proteins among the culture conditions and strains used. Thus, this work provides insights into physiological adaptations of the pneumococcus when it interacts with the host, which may be useful for the design of strategies to combat infections caused by this pathogen.
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(This article belongs to the Special Issue Streptococcus pneumoniae)
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Genetic Analysis, Population Structure, and Characterisation of Multidrug-Resistant Klebsiella pneumoniae from the Al-Hofuf Region of Saudi Arabia
by
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Pathogens 2021, 10(9), 1097; https://doi.org/10.3390/pathogens10091097 - 28 Aug 2021
Abstract
Multidrug-resistant Klebsiella pneumoniae (MDR-KP) is a major public health problem that is globally associated with disease outbreaks and high mortality rates. As the world seeks solutions to such pathogens, global and regional surveillance is required. The aim of the present study was to
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Multidrug-resistant Klebsiella pneumoniae (MDR-KP) is a major public health problem that is globally associated with disease outbreaks and high mortality rates. As the world seeks solutions to such pathogens, global and regional surveillance is required. The aim of the present study was to examine the antimicrobial susceptibility pattern and clonal relatedness of Klebsiella pneumoniae isolates collected for a period of three years through pulse field gel electrophoresis (PFGE). Isolate IDs, antimicrobial assays, ESBL-production, and minimum inhibitory concentrations (MICs) were examined with the Vitek 2 Compact Automated System. IDs were confirmed by 16S rRNA gene sequencing, with the resulting sequences being deposited in NCBI databases. DNA was extracted and resistance genes were detected by PCR amplification with appropriate primers. Isolates were extensive (31%) and multidrug-resistant (65%). Pulsotype clusters grouped the isolates into 22 band profiles that showed no specific pattern with phenotypes. Of the isolates, 98% were ESBL-KP, 69% were carbapenem-resistant Enterobacteriaceae (CRE) strains, and 72.5% comprised the carriage of two MBLs (SIM and IMP). Integrons (ISAba1, ISAba2, and IS18) were detected in 69% of the MDR-KP. Additionally, OXA-23 was detected in 67% of the isolates. This study therefore demonstrates clonal diversity among clinical K. pneumoniae, confirming that this bacterium has access to an enormous pool of genes that confer high resistance-developing potential.
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(This article belongs to the Special Issue Infection and Antimicrobial Resistance of Klebsiella pneumoniae)
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Importance of Molecular Data to Identify Fungal Plant Pathogens and Guidelines for Pathogenicity Testing Based on Koch’s Postulates
by
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Pathogens 2021, 10(9), 1096; https://doi.org/10.3390/pathogens10091096 - 28 Aug 2021
Abstract
Fungi are an essential component of any ecosystem, but they can also cause mild and severe plant diseases. Plant diseases are caused by a wide array of fungal groups that affect a diverse range of hosts with different tissue specificities. Fungi were previously
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Fungi are an essential component of any ecosystem, but they can also cause mild and severe plant diseases. Plant diseases are caused by a wide array of fungal groups that affect a diverse range of hosts with different tissue specificities. Fungi were previously named based only on morphology and, in many cases, host association, which has led to superfluous species names and synonyms. Morphology-based identification represents an important method for genus level identification and molecular data are important to accurately identify species. Accurate identification of fungal pathogens is vital as the scientific name links the knowledge concerning a species including the biology, host range, distribution, and potential risk of the pathogen, which are vital for effective control measures. Thus, in the modern era, a polyphasic approach is recommended when identifying fungal pathogens. It is also important to determine if the organism is capable of causing host damage, which usually relies on the application of Koch’s postulates for fungal plant pathogens. The importance and the challenges of applying Koch’s postulates are discussed. Bradford Hill criteria, which are generally used in establishing the cause of human disease, are briefly introduced. We provide guidelines for pathogenicity testing based on the implementation of modified Koch’s postulates incorporating biological gradient, consistency, and plausibility criteria from Bradford Hill. We provide a set of protocols for fungal pathogenicity testing along with a severity score guide, which takes into consideration the depth of lesions. The application of a standard protocol for fungal pathogenicity testing and disease assessment in plants will enable inter-studies comparison, thus improving accuracy. When introducing novel plant pathogenic fungal species without proving the taxon is the causal agent using Koch’s postulates, we advise the use of the term associated with the “disease symptoms” of “the host plant”. Where possible, details of disease symptoms should be clearly articulated.
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(This article belongs to the Special Issue Filamentous Fungal Pathogens)
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