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DOAJ Open Access 2025
Mpox as Two Global Health Emergencies: Altered Transmission, Genomics, Clinical Manifestation and Public Health Impact

Sanchita Chakraborty, S.R. Rao, Abhijit Poddar

Mpox virus (MPXV) is the only pathogen that triggered two Public Health Emergency of International Concern (PHEIC) declarations, first in July 2022 and then again in August 2024. The 2022 outbreak was attributed primarily to clade IIb MPXV, specifically lineage B.1. However, the 2024 global outbreak was largely due to the emergence of clade Ib MPXV, which was first identified in the Sud Kivu region of the Democratic Republic of the Congo in 2023. During this period, the transmission route of MPXV transitioned from primarily zoonotic spillovers to sustained human-to-human transmission, disproportionately affecting vulnerable groups such as men-who-have-sex-with-men, immunocompromised individuals and marginalized populations with limited access to healthcare. This shift has been driven by critical mutations in genes associated with viral fitness, immune evasion and transmission dynamics. Moreover, these changes correspond with atypical and often milder yet more transmissible clinical presentations, complicating the detection and management of cases. Despite these challenges, health system preparedness has remained uneven. High-income countries leverage existing infrastructure to facilitate rapid responses through proactive policies and financial commitments. However, many low- and middle-income countries struggle with delayed case detection, limited surge capacity, community unawareness and fragmented outbreak governance. Although diagnostics, vaccines and antivirals have advanced, issues such as accessibility, affordability and distribution have persisted, hindering global solidarity efforts. This narrative review integrates evidence on the evolution of MPXV clades, clinical heterogeneity, and public health responses. Furthermore, by learning from past outbreaks, this review proposes actionable, time-sensitive recommendations to strengthen surveillance, ensure equitable deployment of countermeasures, secure supply chains and embed One Health approaches for increased resilience.

Infectious and parasitic diseases
DOAJ Open Access 2024
Impact of COVID-19 health precautions on asymptomatic Streptococcus pyogenes carriage in palestinian children: a pre- and post-pandemic study

Ibrahim Amer Ghannam, Rana Mahmoud Maraqa, Duha Shokri Qawasmeh et al.

Abstract Background Streptococcus pyogenes (Group A Streptococcus, GAS) is a significant pathogen that causes diverse infections, ranging from pharyngitis to severe invasive diseases. Asymptomatic carriage in children is pivotal for transmission. The COVID-19 pandemic’s health measures, including mask wearing and enhanced hand hygiene, likely influenced GAS transmission dynamics. This study evaluated the impact of these precautions on the prevalence of asymptomatic pharyngeal GAS carriage among schoolchildren in the southern West Bank, Palestine. Methods This cross-sectional study was conducted in two phases: pre-COVID-19 (November 2019–January 2020) and post-COVID-19 (November 2023–April 2024). Throat swabs were collected from 701 children (345 pre-COVID-19, 356 post-COVID-19) via cluster sampling. The samples were tested with the ABON Strep A rapid test and confirmed by culture. Sociodemographic, health, and household data were also collected. The statistical analyses included descriptive statistics, chi-square tests, and binary logistic regression. Results The prevalence of asymptomatic pharyngeal GAS carriage declined from 15.7% pre-COVID-19 to 10.4% post-COVID-19 (p = 0.038). Significant reductions were observed among urban residents (23.5–10.1%, p = 0.003) and those from medium socioeconomic backgrounds (16.0–9.1%, p = 0.008). Compared with urban residents, rural residents had lower GAS carriage rates (adjusted OR = 0.505, p = 0.023). Carriage rates also decreased among children with frequent sore throats (17.6–7.3%, p = 0.007) and those using private wells (52.5–14.9%, p < 0.001). Higher BMI was a significant risk factor (adjusted OR = 17.68, p < 0.001), whereas frequent tooth brushing (adjusted OR = 0.055, p < 0.001) and hand washing (adjusted OR = 0.367, p < 0.001) were protective factors. Conclusions COVID-19-related health precautions were correlated with a significant reduction in asymptomatic GAS carriage among Palestinian children. These findings suggest that public health measures, such as mask wearing and hand hygiene, can influence the transmission of respiratory pathogens. Ongoing surveillance and targeted interventions are essential for managing GAS infections, particularly in resource-limited settings.

Infectious and parasitic diseases
DOAJ Open Access 2024
Oritavancin as sequential therapy for Gram-positive bloodstream infections

Williams Monier Texidor, Matthew A. Miller, Kyle C. Molina et al.

Abstract Background Oritavancin, a long-acting lipoglycopeptide approved for use in acute bacterial skin and skin structure infections, has limited data evaluating use in serious infections due to Gram-positive organisms. We aimed to assess the effectiveness and safety of oritavancin for consolidative treatment of Gram-positive bloodstream infections (BSI), including infective endocarditis (IE). Methods We conducted a retrospective cohort study evaluating adult patients admitted to University of Colorado Hospital from March 2016 to January 2022 who received ≥ 1 oritavancin dose for treatment of Gram-positive BSI. Patients were excluded if the index culture was drawn at an outside facility or were > 89 years of age. The primary outcome was a 90-day composite failure (clinical or microbiological failure) in those with 90-day follow-up. Secondary outcomes included individual components of the primary outcome, acute kidney injury (AKI), infusion-related reactions (IRR), and institutional cost avoidance. Results Overall, 72 patients were included. Mean ± SD age was 54 ± 16 years, 61% were male, and 10% had IE. Organisms most commonly causing BSI were Staphylococcus aureus (68%, 17% methicillin-resistant), followed by Streptococcus spp. (26%), and Enterococcus spp. (10%). Patients received standard-of-care antibiotics before oritavancin for a median (IQR) of 11 (5–17) days. Composite failure in the clinically evaluable population (n = 64) at 90-days occurred in 14% and was composed of clinical and microbiological failure, which occurred in 14% and 5% of patients, respectively. Three patients (4%) experienced AKI after oritavancin, and two (3%) experienced an IRR. Oritavancin utilization resulted in earlier discharge for 94% of patients corresponding to an institutional cost-avoidance of $3,055,804 (mean $44,938/patient) from 1,102 hospital days saved (mean 16 days/patient). Conclusions The use of oritavancin may be an effective sequential therapy for Gram-positive BSI to facilitate early discharge resulting in institutional cost avoidance.

Infectious and parasitic diseases
DOAJ Open Access 2022
The impact of globalization and climate change on Trichinella spp. epidemiology

Edoardo Pozio

The main reservoir hosts of nematodes of the genus Trichinella are wild carnivores, although most human infections are caused by the consumption of pork. This group of zoonotic parasites completes the entire natural life cycle within the host organism. However, there is an important phase of the cycle that has only been highlighted in recent years and which concerns the permanence of the infecting larvae in the striated muscles of the host carcasses waiting to be ingested by a new host. To survive in this unique biological niche, Trichinella spp. larvae have developed an anaerobic metabolism for their survival in rotting carcasses and, for some species, a resistance to freezing for months or years in cold regions. Climate changes with increasingly temperatures and reduction of environmental humidity lower the survival time of larvae in host carcasses. In addition, environmental changes affect the biology and ecology of the main host species, reducing their number and age composition due to natural habitat fragmentation caused by increasing human settlements, extensive monocultures, increasing number of food animals, and reduction of trophic chains and biodiversity. All of these factors lead to a reduction in biological and environmental complexity that is the key to the natural host-parasite balance. In conclusion, Trichinella nematodes can be considered as an indicator of a health natural ecosystem.

Infectious and parasitic diseases
DOAJ Open Access 2022
Current Status of Fasciolosis of Goat in Sylhet, Bangladesh: An Integrated Morphomolecular Study

Chamali Akter Shykat, Saiful Islam, Foyez Ahmed et al.

Epidemiological information and proper identification of Fasciola species present in Bangladesh are important for control. This study was aimed at determining the prevalence of liver fluke infection of goats in Sylhet, Bangladesh, and identifying those using integrated morphometric and molecular techniques. A total of 260 slaughtered goats (Capra hircus) were examined, and flukes were collected from infected liver using sterilized forceps. Fasciolosis prevalence in goats was 35.38% (92/260) across all age and sex categories. Female goats were found more infected (37.14%, 65/175) than male goats (31.76%, 27/85), while infection rate was found higher in young animals (37.91%, 69/182) compared to adults (29.48% 23/78). Infection rate was observed higher in rainy season (52.96%, 45/85), followed by winter (27.38%, 26/95) and summer (26.25%, 21/80). Collected flukes were examined by light microscopy after being stained with Semichon’s acetocarmine, and sequences of mtDNA Cox1 genes were obtained. Ten adult flukes were measured, 38.72±3.37 mm in length and 11.8±1.9 mm in width. Based on morphometric features especially branching of the testis and body length/body width ratios (3.28±0.42), the flukes were primarily identified as Fasciola gigantica. Amplicon sequences were compared by BLAST and the cox1 sequences showed 97.1-99.3% similarity with the reference sequences (F. gigantica and Fasciola sp.) from GenBank. In this study, we found a considerable prevalence of fascioliasis in goats, and F. gigantica was solely identified with variation. To control these parasites and prevent potential public health risks, appropriate control techniques must be developed.

Infectious and parasitic diseases
DOAJ Open Access 2021
Two Novel ATP2C1 Mutations in Portuguese Patients with Hailey-Hailey Disease

Sofia Antunes-Duarte, Maria Mendonça-Sanches , Rita Pimenta et al.

Hailey-Hailey disease (HHD) is a rare autosomal dominant acantholytic dermatosis. It is characterized by a recurrent eruption of vesicles, erosions, and scaly erythematous plaques involving intertriginous areas and first occurring after puberty, mostly in the third or fourth decade. In 2000, mutations in the ATP2C1 gene on band 3q22.1, encoding the secretory pathway Ca2+/Mn2+-ATPase protein 1(hSPCA1), have been identified as the cause of HHD. We report the identification of two novel mutations of ATP2C1 gene in two Portuguese patients, which expands the spectrum of ATP2C1 mutations underlying HHD and provides useful information for genetic counseling.

Dermatology, Infectious and parasitic diseases
DOAJ Open Access 2020
Estimates for Lyme borreliosis infections based on models using sentinel canine and human seroprevalence data

Michael J. Cook, Basant K. Puri

Two models were developed to estimate Lyme borreliosis (LB) cases. One was based on the seroprevalence of Borrelia infections in human samples. This model used corrections for false negative and false positive results from published test sensitivity and specificity measures. A second model based on Borrelia infections in sentinel dogs was used to quantify the prevalence of Lyme disease Borrelia infections in humans; the reference baseline for this model was human and canine infections in Germany. A comparison of the two models is shown and differences discussed. The relationships between incidence, prevalence and total infection burden for LB were derived from published data and these were used in both models to calculate annual incidence, prevalence and total LB infections. The modelling was conservative and based on medical insurance records coded for erythema migrans. Linear model growth rates were used in place of the commonly adopted exponential growth. The mean of the two models was used to create estimates for various countries and continents. Examples from the analyses for LB estimated for 2018 include: incidence – USA 473,000/year, Germany 471,000/year, France 434,000/year and UK 132,000/year; prevalence – USA 2.4 million, Germany 2.4 million, France 2.2 million and UK 667,000; total infections – USA 10.1 million, Germany 10.0 million, France 9.3 million and UK 2.8 million. Estimates for the world for 2018 are: incidence 12.3 million/year; prevalence 62.1 million; and total infection burden 262.0 million. These figures are far higher than officially published data and reflect not only the underestimation of diagnosed cases, which is acknowledged by health agencies, but also undiagnosed and misdiagnosed cases.

Infectious and parasitic diseases
DOAJ Open Access 2020
Case reports of latent HBV hepatitis in patients after neurosurgical treatment for hypothalamic and pituitary tumors

Kuniyasu Niizuma, Yoshikazu Ogawa, Takayuki Kogure et al.

Abstract Background Hepatitis B virus (HBV) infection is a major public health problem worldwide. More than 2 billion people have been exposed to HBV, and about 257 million individuals are chronic carriers of HBV. HBV reactivation has been increasingly reported in HBV carriers who have undergone immunosuppression or chemotherapy, resulting in mortality. Treatment of hypothalamic/pituitary tumors in HBV carriers requires extensive care to avoid HBV reactivation as steroid therapy is required after surgery for hypothalamic/pituitary tumors. Case presentation This retrospective review identified 5 patients, who were HBV carriers positive for hepatitis B surface antigen among 1352 patients with surgically treated hypothalamic/pituitary tumor in Kohnan Hospital between February 2007 and April 2017. Transsphenoidal surgery was performed with particular attention to prevent damage to the pituitary gland, with delicate manipulation to minimize postoperative steroid coverage. All patients received nucleot(s)ide analogue to control HBV-DNA levels before the surgery. As a result, all patients had a good clinical course. Blood examinations found a transient increase of liver enzymes and HBV-DNA levels in all patients, which started to decrease within 2 weeks after surgery. No specific treatment other than nucleot(s)ide analogues was needed to maintain liver function, and all patients returned to their previous activities including reinstatement. Conclusion Initiation of nucleot(s)ide analogues administration prior to the surgery for hypothalamic/pituitary tumors can be an effective strategy for preventing reactivation in HBV carriers. Appropriate screening of the patient’s HBV phase, optimal timing of nucleot(s)ide analogues -administration, and administration period of nucleot(s)ide analogues need to be established.

Infectious and parasitic diseases
DOAJ Open Access 2018
Identification of wild-caught phlebotomine sand flies from Crete and Cyprus using DNA barcoding

Emmanouil Dokianakis, Nikolaos Tsirigotakis, Vasiliki Christodoulou et al.

Abstract Background Phlebotomine sand flies (Diptera: Psychodidae) are vectors of Leishmania spp., protozoan parasites responsible for a group of neglected diseases called leishmaniases. Two sand fly genera, Phlebotomus and Sergentomyia, contain species that are present in the Mediterranean islands of Crete and Cyprus where the visceral (VL), cutaneous (CL) and canine (CanLei) leishmaniases are a public health concern. The risk of transmission of different Leishmania species can be studied in an area by monitoring their vectors. Sand fly species are traditionally identified using morphological characteristics but minute differences between individuals or populations could be overlooked leading to wrong epidemiological predictions. Molecular identification of these important vectors has become, therefore, an essential tool for research tasks concerning their geographical distribution which directly relates to leishmaniasis control efforts. DNA barcoding is a widely used molecular identification method for cataloguing animal species by sequencing a fragment of the mitochondrial gene encoding cytochrome oxidase I. Results DNA barcoding was used to identify individuals of five sand fly species (Phlebotomus papatasi, P. similis, P. killicki, Sergentomyia minuta, S. dentata) circulating in the islands of Crete and Cyprus during the years 2011–2014. Phlebotomus papatasi is a known vector of zoonotic CL in the Middle East and it is found in both islands. Phlebotomus similis is the suspected vector of Leishmania tropica in Greece causing anthroponotic CL. Phlebotomus killicki was collected in Cyprus for the first time. Sergentomyia minuta, found to present intraspecific diversity, is discussed for its potential as a Leishmania vector. Molecular identification was consistent with the morphological identification. It successfully identified males and females, which is difficult when using only morphological characters. A phylogenetic tree was constructed based on the barcodes acquired, representing their genetic relationships along with other species from the area studied. All individuals identified were clustered according to their species and subgenus. Conclusions Molecular identification of sand flies via DNA barcoding can accurately identify these medically important insects assisting traditional morphological tools, thus helping to assess their implication in Leishmania transmission.

Infectious and parasitic diseases
DOAJ Open Access 2018
Fenómeno de Lúcio: Resposta ao Tratamento Alternativo com Poliquimioterapia Multibacilar

Camila Araujo Dantas, Caroline Medeiros Prohmann, Lorena Barcelos e Silva et al.

A hanseníase é uma doença infectocontagiosa de evolução crónica, causada pelo Mycobacterium leprae. Seu curso crónico pode ser interrompido por episódios reacionais agudos ou subagudos. O fenómeno de Lúcio é uma reação imunológica vasculítica que ocorre em doentes com lepra lepromatosa. Surge com máculas purpúricas que evoluem com necrose e ulceração, de forma ascendente, deixando cicatriz atrófica. Os autores descrevem o caso de um paciente de 73 anos, sexo masculino, com lesões ulceronecróticas em membros inferiores e exposição tendinosa em calcâneo. Com base em dados clínico-laboratoriais e exame dermatológico, confirmado diagnóstico de lepra lepromatosa com vasculite do tipo fenómeno de Lúcio. Evoluiu com boa resposta ao esquema alternativo de tratamento com poliquimioterapia multibacilar.

Dermatology, Infectious and parasitic diseases
DOAJ Open Access 2017
Outbreak tracking of Aleutian mink disease virus (AMDV) using partial NS1 gene sequencing

P. Ryt-Hansen, C.K. Hjulsager, E.E. Hagberg et al.

Abstract Background Aleutian Mink Disease (AMD) is an infectious disease of mink (Neovison vison) and globally a major cause of economic losses in mink farming. The disease is caused by Aleutian Mink Disease Virus (AMDV) that belongs to the genus Amdoparvovirus within the Parvoviridae family. Several strains have been described with varying virulence and the severity of infection also depends on the host’s genotype and immune status. Clinical signs include respiratory distress in kits and unthriftiness and low quality of the pelts. The infection can also be subclinical. Systematic control of AMDV in Danish mink farms was voluntarily initiated in 1976. Over recent decades the disease was mainly restricted to the very northern part of the country (Northern Jutland), with only sporadic outbreaks outside this region. Most of the viruses from this region have remained very closely related at the nucleotide level for decades. However, in 2015, several outbreaks of AMDV occurred at mink farms throughout Denmark, and the sources of these outbreaks were not known. Methods Partial NS1 gene sequencing, phylogenetic analyses data were utilized along with epidemiological to determine the origin of the outbreaks. Results The phylogenetic analyses of partial NS1 gene sequences revealed that the outbreaks were caused by two different clusters of viruses that were clearly different from the strains found in Northern Jutland. These clusters had restricted geographical distribution, and the variation within the clusters was remarkably low. The outbreaks on Zealand were epidemiologically linked and a close sequence match was found to two virus sequences from Sweden. The other cluster of outbreaks restricted to Jutland and Funen were linked to three feed producers (FP) but secondary transmissions between farms in the same geographical area could not be excluded. Conclusion This study confirmed that partial NS1 sequencing can be used in outbreak tracking to determine major viral clusters of AMDV. Using this method, two new distinct AMDV clusters with low intra-cluster sequence diversity were identified, and epidemiological data helped to reveal possible ways of viral introduction into the affected herds.

Infectious and parasitic diseases
DOAJ Open Access 2016
Dengue serotype immune-interactions and their consequences for vaccine impact predictions

José Lourenço, Mario Recker

Dengue is one of the most important and wide-spread viral infections affecting human populations. The last few decades have seen a dramatic increase in the global burden of dengue, with the virus now being endemic or near-endemic in over 100 countries world-wide. A recombinant tetravalent vaccine candidate (CYD-TDV) has recently completed Phase III clinical efficacy trials in South East Asia and Latin America and has been licensed for use in several countries. The trial results showed moderate-to-high efficacies in protection against clinical symptoms and hospitalisation but with so far unknown effects on transmission and infections per se. Model-based predictions about the vaccine's short- or long-term impact on the burden of dengue are therefore subject to a considerable degree of uncertainty. Furthermore, different immune interactions between dengue's serotypes have frequently been evoked by modelling studies to underlie dengue's oscillatory dynamics in disease incidence and serotype prevalence. Here we show how model assumptions regarding immune interactions in the form of antibody-dependent enhancement, temporary cross-immunity and the number of infections required to develop full immunity can significantly affect the predicted outcome of a dengue vaccination campaign. Our results thus re-emphasise the important gap in our current knowledge concerning the effects of previous exposure on subsequent dengue infections and further suggest that intervention impact studies should be critically evaluated by their underlying assumptions about serotype immune-interactions.

Infectious and parasitic diseases
DOAJ Open Access 2015
Prevalence of Intestinal Parasites among Food-handlers in Shiraz, Iran

Mohammad Hossein MOTAZEDIAN, Mohsen NAJJARI, Mohammad EBRAHIMIPOUR et al.

Background: Parasitic intestinal infections are still among socioeconomic prob­lems in the world, especially in developing countries like Iran. Food-handlers that directly deal with production and distribution of foods between societies are one of the most important sources to transmit parasitic infections to humans. The aim of this study was to determine the prevalence of intestinal parasitic infections among food-handlers in Shiraz, Iran. Methods: In this cross-sectional study, 1021 feces samples were randomly col­lected from food-handlers in Shiraz, central Iran from August to September 2013. Two different methods, routine direct fecal examination and Formalin –Ethyl ace­tate concentration as a complementary technique, were done to detect parasites. Results: The prevalence of parasitic organisms was 10.4% in the food-handlers. The most species of the protozoan parasites were G. lamblia, E. coli and B. hominis; meanwhile, only one infection by H. nana (0.1%) was detected in this group. Mixed infections were observed in 13.2% (n=14/106) of positive cases. The majority of participants were male (57%); however, data analysis showed significant statistical difference in the rate of infection between females 11.9% (n=53/444) and males 9% (n=52/577) (P=0. 024). There was no significant statistical difference in the rate of infection among different educational and occupation groups. Conclusion: Although decreasing of helminthic infections is distinct, but infecting with protozoan parasites is still important in food-handlers. Concentration tech­nique is more useful than direct smear technique, especially for detection parasites in low number. High level of education in our study showed that training courses in this group could be effective in the implementation of control and prevention programs.

Infectious and parasitic diseases
DOAJ Open Access 2014
Zum Einsatz von Informationstechnologie zur Verbesserung der Arzneimitteltherapiesicherheit (Memorandum AMTS-IT)

Ammenwerth, Elske, Aly, Amin-Farid, Bürkle, Thomas et al.

[english] Information technology in health care has a clear potential to improve quality and efficiency of health care, especially in the area of medication processes. On the other side, existing studies show possible adverse effects on patient safety when IT for medication-related processes is developed, introduced or used inappropriately. The objective of this paper is to summarize definitions and observations on IT usage in pharmacotherapy, and to derive recommendations and future research priorities for decision makers and domain experts. The recommendations address, among others, a stepwise and comprehensive strategy for IT usage in medication processes, the integration of contextual information for alert generation, the involvement of patients, the semantic integration of information resources, usability and adaptability of IT solutions and the need for their continuous evaluation.

Computer applications to medicine. Medical informatics, Infectious and parasitic diseases

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