Different Sources Of Infection Research Articles

Midregional-proAdrenomedullin as a prognostic tool in sepsis and septic shock: A systematic review and meta-analysis.

Midregional-proAdrenomedullin (MR-proADM) has been recently proposed as a tool in patients with sepsis and septic shock. Our aim was to evaluate the prognostic role of MR-proADM in hospitalized patients with sepsis and septic shock. PRISMA guideline was followed. MEDLINE and EMBASE were searched up to June 2023. Primary outcome was mean difference in MR-proADM among survivors and nonsurvivors, secondary outcome mean difference in MR-proADM according to infection severity and type. Risk of bias was evaluated using Newcastle-Ottawa scale for observational studies and Cochrane tool for randomized trials. Pooled mean differences (MD) with corresponding 95% confidence intervals (CIs) were calculated in a random-effects model. Twenty-four studies included 6730 adult patients (1208 nonsurvivors and 5522 survivors) and three studies included 195 paediatric patients (30 nonsurvivors and 165 survivors). A total of 10, 4 and 13 studies included, respectively, patients with sepsis (3602 patients), septic shock (386 patients) and a mixed population (2937 patients). Twenty-one studies included patients with different source of infection, three with pneumonia and one with a catheter-related infection. Most studies (n = 12) had a follow-up of 28 days. In adult cohort, pooled mean difference between nonsurvivors and survivors of MR-proADM was 2.55 mmol/L (95% CI: 1.95-3.15) with higher values in patients with septic shock (4.25 mmol/L; 95% CI, 2.23-6.26 mmol/L) than in patients with sepsis (1.77 mmol/L; 95% CI: 1.11-2.44 mmol/L). In paediatric cohort, pooled mean difference was 3.11 mmol/L (95% CI: -0.02-6.24 mmol/L). Higher values of MR-proADM are detectable in nonsurvivors adult and paediatric-hospitalized patients with sepsis or septic shock.

The MIC distribution of dalbavancin differs between different coagulase-negative staphylococci.

CoNS constitute a significant part of the human microbiota of skin and mucous membranes. They can cause nosocomial infections, and have shown decreased susceptibility to several antibiotics. The few remaining treatment options include (lipo)glycopeptides such as dalbavancin. However, there is a lack of knowledge concerning whether susceptibility to lipoglycopeptides varies between different species of CoNS. To determine the susceptibility to dalbavancin in different species of CoNS. We investigated 480 bacterial isolates from 10 CoNS species: Staphylococcus epidermidis, Staphylococcus capitis, Staphylococcus caprae, Staphylococcus haemolyticus, Staphylococcus lugdunensis, Staphylococcus warneri, Staphylococcus pettenkoferi, Staphylococcus hominis, Staphylococcus sciuri and Staphylococcus simulans. The isolates were randomly selected from different sources of infection, including blood isolates, as well as deep and superficial infections. Antibiotic susceptibility was tested with the gradient test method. There was a statistically significant difference (ANOVA; P < 0.0001) in the MIC distribution for dalbavancin between different CoNS species. S. sciuri was the least susceptible species, with 90% of the isolates having an MIC value for dalbavancin above the EUCAST breakpoint of 0.125 mg/L. The lowest MIC90 values were seen for S. capitis, S. simulans and S. caprae (all 0.032 mg/L). This study demonstrated a difference in dalbavancin susceptibility between different CoNS species, suggesting that species-specific breakpoints for CoNS should be further investigated.

Sex differences in clinical presentation and mortality in emergency department patients with sepsis

Background There is growing awareness that sex differences are associated with different patient outcomes in a variety of diseases. Studies investigating the effect of patient sex on sepsis-related mortality remain inconclusive and mainly focus on patients with severe sepsis and septic shock in the intensive care unit. We therefore investigated the association between patient sex and both clinical presentation and 30-day mortality in patients with the whole spectrum of sepsis severity presenting to the emergency department (ED) who were admitted to the hospital. Materials and methods In our multi-centre cohort study, we retrospectively investigated adult medical patients with sepsis in the ED. Multivariable analysis was used to evaluate the association between patient sex and all-cause 30-day mortality. Results Of 2065 patients included, 47.6% were female. Female patients had significantly less comorbidities, lower Sequential Organ Failure Assessment score and abbreviated Mortality Emergency Department Sepsis score, and presented less frequently with thrombocytopenia and fever, compared to males. For both sexes, respiratory tract infections were predominant while female patients more often had urinary tract infections. Females showed lower 30-day mortality (10.1% vs. 13.6%; p = .016), and in-hospital mortality (8.0% vs. 11.1%; p = .02) compared to males. However, a multivariable logistic regression model showed that patient sex was not an independent predictor of 30-day mortality (OR 0.90; 95% CI 0.67–1.22; p = .51). Conclusions Females with sepsis presenting to the ED had fewer comorbidities, lower disease severity, less often thrombocytopenia and fever and were more likely to have a urinary tract infection. Females had a lower in-hospital and 30-day mortality compared to males, but sex was not an independent predictor of 30-day mortality. The lower mortality in female patients may be explained by differences in comorbidity and clinical presentation compared to male patients. KEY MESSAGES Only limited data exist on sex differences in sepsis patients presenting to the emergency department with the whole spectrum of sepsis severity. Female sepsis patients had a lower incidence of comorbidities, less disease severity and a different source of infection, which explains the lower 30-day mortality we found in female patients compared to male patients. We found that sex was not an independent predictor of 30-day mortality; however, the study was probably underpowered to evaluate this outcome definitively.

Determination the Inhibition activity of Magnesium Oxide Nanoparticles Synthesized by Aspergillus niger against some uncommon bacterial species which isolated from different sources of infection

The resistance of bacteria to chemically manufactured antibiotics is dangerous in human health,this has made the need for continuous detection of diverse resources ,especially from naturalsources in the treatment of human diseases. The current study employs Aspergillus niger for theformation of of Magnesium Oxide Nanoparticles, and it involves the antimicrobial activity of theparticles against some of uncommon bacterial species which include Gram positive Aeromonassalmonicida, Kocuria rosea and Alloiococcus otitis and Gram negative Acinatobactercalcoaceticus, Pantoea agglomerans and Ochrobactrum anthropic by agar wells diffusionmethod. The results were indicated that biosynthesized of MgO NPs were found as extracellularand it was appear in the range of size 40-90 nm through characterization technique such asScanning Electron Microscopy (SEM), and assurance by UV-Visible spectroscopy for theabsorbance band at 258 nm, The results revealed that MgO NPs is an effective antibacterial agentagainst Gram positive Aeromonas salmonicida , Kocuria rosea and Alloiococcus otitis and thezone inhibition diameter was at 20,19 and23 mm respectively compared with inhibition effects ofciprofloxacin antibiotics at 18, 17and 20 mm respectively. while against Gram negativeAcinatobacter calcoaceticus, Pantoea agglomerans and Ochrobactrum anthropic bacteria wasat 18,20,19 mm respectively, compared with inhibition effects of ciprofloxacin antibiotics at 16,20 and 15 mm respectively.

Activity of imipenem/relebactam against Enterobacterales and Pseudomonas aeruginosa in Spain. SMART 2016-2020.

To determine susceptibility to the novel β-lactam/β-lactamase inhibitor combination imipenem/relebactam in clinical isolates recovered from intra-abdominal (IAI), urinary (UTI), respiratory (RTI) and bloodstream (BSI) infections in the SMART (Study for Monitoring Antimicrobial Resistance Trends) study in SPAIN during 2016 - 2020. Broth microdilution MICs for imipenem/relebactam and comparators were determined by a central laboratory against isolates of Enterobacterales and Pseudomonas aeruginosa. MICs were interpreted using EUCAST-2021 breakpoints. In total, 5,210 Enterobacterales and 1,418 P. aeruginosa clinical isolates were analyzed. Imipenem/relebactam inhibited 98.8% of Enterobacterales. Distinguishing by source of infection susceptibility was 99.1% in BSI, 99.2% in IAI, 97.9% in RTI, and 99.2% in UTI. Of intensive care unit isolates (ICU) 97.4% were susceptible and of non-ICU isolates 99.2% were susceptible. In Enterobacterales, activity against Class A, Class B and Class D carbapenemases was 96.2%, 15.4% and 73.2%, respectively. In P. aeruginosa, imipenem/relebactam was active in 92.2% of isolates. By source of infection it was 94.8% in BSI, 92.9% in IAI, 91.7% in RTI, and 93.1% in UTI. An 88.7% of ICU isolates and 93.6% of non-ICU isolates were susceptible to imipenem/relebactam. Imipenem/relebactam remained active against P. aeruginosa ceftazidime-resistant (76.3%), cefepime-resistant (73.6%), imipenem-resistant (71.5%) and piperacillin-resistant (78.7%) isolates. Of all multidrug-resistant or difficult-to-treat resistance P. aeruginosa isolates, 75.1% and 46.2%, respectively, were susceptible to imipenem/relebactam. Imipenem/relebactam showed high rates of susceptibility in Enterobacterales and P. aeruginosa isolates from different sources of infection as well as depending on patients' location (ICU or non-ICU scenarios).

Concordance Between Initial Presumptive and Final Adjudicated Diagnoses of Infection Among Patients Meeting Sepsis-3 Criteria in the Emergency Department.

Guidelines emphasize rapid antibiotic treatment for sepsis, but infection presence is often uncertain at initial presentation. We investigated the incidence and drivers of false-positive presumptive infection diagnosis among emergency department (ED) patients meeting Sepsis-3 criteria. For a retrospective cohort of patients hospitalized after meeting Sepsis-3 criteria (acute organ failure and suspected infection including blood cultures drawn and intravenous antimicrobials administered) in 1 of 4 EDs from 2013 to 2017, trained reviewers first identified the ED-diagnosed source of infection and adjudicated the presence and source of infection on final assessment. Reviewers subsequently adjudicated final infection probability for a randomly selected 10% subset of subjects. Risk factors for false-positive infection diagnosis and its association with 30-day mortality were evaluated using multivariable regression. Of 8267 patients meeting Sepsis-3 criteria in the ED, 699 (8.5%) did not have an infection on final adjudication and 1488 (18.0%) patients with confirmed infections had a different source of infection diagnosed in the ED versus final adjudication (ie, initial/final source diagnosis discordance). Among the subset of patients whose final infection probability was adjudicated (n = 812), 79 (9.7%) had only "possible" infection and 77 (9.5%) were not infected. Factors associated with false-positive infection diagnosis included hypothermia, altered mental status, comorbidity burden, and an "unknown infection source" diagnosis in the ED (odds ratio: 6.39; 95% confidence interval: 5.14-7.94). False-positive infection diagnosis was not associated with 30-day mortality. In this large multihospital study, <20% of ED patients meeting Sepsis-3 criteria had no infection or only possible infection on retrospective adjudication.

Assessment of Genetic Diversity of Noroviruses Circulating in Temporary Accommodation Centers for Refugees in the Rostov Region in 2022 Using the NoroNetRus Online Software

Introduction: It is obvious that effective investigation of norovirus outbreaks is impossible without the use of methods enabling differentiation of pathogen genotypes, the principal of which is the determination of the type of capsid and polymerase based on sequencing data. Yet, unstable operation of international services for assessment of norovirus genomes from a number of IP addresses located in the Russian Federation has been noted recently, which may affect the efficiency and promptness of inves- tigation of norovirus outbreaks in our country. Objective: To develop domestic software for genotyping of noroviruses and further assessment of genetic diversity of norovi- ruses identified in the year 2022 in the Rostov Region. Materials and methods: The materials for the study were stool samples from 210 patients with symptoms of gastrointestinal infec- tions from temporary accommodation centers for refugees and children’s centers. The study population included patients aged 1 month to 74 years with symptoms of acute bowel infections. Detection of the pathogen RNA was carried out using a reagent kit AmpliSens® OKI screen-FL (Moscow, Russia). Fragment sequencing was performed using a genomic analyzer SeqStudio (Thermo Fisher, USA). The authors’ software was developed in the Java and Python programming languages. Results: We developed a domestic NoroNetRus software allowing determination of the type of capsid and polymerase of noroviruses based on sequencing data. The software is free of charge and available online at http://antiplague.ru/noronetrus. The fragment analysis of VP1 gene sequences for 25 norovirus samples showed that they belonged to three different genotypes (GII.4 Sydney, GII.10, and GII.17), and the genotype GII.10, in its turn, was distributed between two different clusters. Our findings indicate the existence of at least four different sources of infection. Conclusion. The data obtained indicate the circulation of at least four different genovariants of the causative agent of norovirus infection in the Rostov Region in 2022.

Polymorphisms of the TLR4 gene: Risk factor for chronicity and severity in oral vectorial Chagas disease

Chagas disease is one of the parasitic infections with the greatest socio-economic impact in Latin America. In Venezuela, epidemiological data has shown different sources of infection, such as the vectorial route by oral transmission. Given the importance of the TLR4 gene in the innate immune response triggered by infection with Trypanosoma cruzi, this work analyses the role of TLR4 polymorphisms and its possible effect on cytokine expression. Genomic DNA was extracted from the peripheral blood of patients from the main outbreak of oral Chagas disease in Venezuela (n = 90), as well as from a group of healthy individuals (n = 183). Subsequently, peripheral blood was also extracted from individuals with different TLR4 haplotypes and then stimulated with LPS to determine the cytokine concentration by ELISA. The internalization of TLR4 was evaluated by flow cytometry. In comparison to healthy individuals, the analysis showed a significantly increased frequency of the Asp/Gly genotype in symptomatic patients. Also, observed a correlation of the 299/399 haplotype with a significant decrease in cytokine concentration and disease severity. Finally, the parasites’ trypomastigotes cause the internalization or negative regulation of TLR4. The variants of TLR4 associated with low production of cytokines may be a risk factor for chronicity and severity (cardiac involvement) in oral vectorial Chagas disease.

Epidemiological characteristics of three local epidemics of COVID-19 in Guangzhou

Objective: To understand the epidemiological characteristics of three local COVID-19 epidemics in Guangzhou and provide reference for optimizing strategies and measures of COVID-19 prevention and control. Methods: The data of local COVID-19 cases in Guangzhou reported as of June 18, 2021 were collected from National Notifiable Disease Report System of China. The software Excel 2019 and SPSS 22.0 were applied for data cleaning and statistical analysis. Results: A total of 726 COVID-19 cases were reported in the three local epidemics in Guangzhou. In the epidemic associated with the outbreak of COVID-19 in Hubei province, 366 cases were reported. Most cases were female (51.6%, 189/366), aged 18-65 years (81.4%, 298/366), jobless/unemployed (32.2%, 118/366) and retired persons (20.2%,74/366). The initial symptoms of most cases were fever (71.6%, 250/349) and cough (60.7%, 212/349). In the epidemic associated with the imported COVID-19 cases from Africa, 207 cases were reported. Most cases were aged 18-40 years (72.9%, 151/207), male (69.6%, 144/207), and engaged in commercial services (62.3%,129/207). The initial symptoms of most cases were no obvious discomfort (55.6%, 15/27) and cough (37.0%, 10/27). In the epidemic associated with Delta variant of SARS-CoV-2, 153 cases were reported, in which women accounted for 58.8% (90/153), most cases were over 41 years old (64.7%,99/153), and retired persons accounted for the highest proportion (32.0%,49/153). The initial symptoms of most cases were cough (32.9%, 48/146) and no obvious discomfort (28.1%, 41/146). The household secondary attack rates of the three local epidemics were 11.2%, 5.7% and 11.5%, respectively. The median (P25, P75) of incubation periods were 6.5 (4.0,10.8) d, 4.0 (2.5, 6.0) d and 4.0 (3.0,5.0) d. The serial intervals median (P25, P75) were 4.0 (3.0, 8.0) d, 4.0 (2.5, 6.0) d and 3.0 (2.0,5.0) d. There were significant differences in gender, age, occupation, initial symptoms, household secondary attack rate and incubation period among the three local COVID-19 epidemics (all P<0.05). In the proportion of the case finding way, passive detection in patient treatment were mainly 44.3%(162/366) in the epidemic associated with the outbreak of COVID-19 in Hubei province,but active community case screening [58.5% (121/207) and 27.5% (24/153)] and close contact management in imported case were mostly [33.3% (69/207) and 67.3% (103/153)] in the epidemic associated with the imported COVID-19 cases from Africa and with Delta variant of SARS-CoV-2, respectively. Conclusions: Due to the different sources of infection, strain types and prevention and control strategies, the epidemiological characteristics of the three local COVID-19 epidemics in Guangzhou differed in demographics, clinical symptoms, transmission routes and case finding, which suggested that it is necessary to improve the key population and common symptom monitoring in the routine prevention and control of COVID-19 to prevent the reemerge of the epidemic.

Longitudinal social network analysis of avian mycobacteriosis incidence in a large population of zoo birds

The goal of this study was to evaluate longitudinal patterns of avian mycobacteriosis spread through a social network. Specifically, we wanted to determine whether the patterns of connectivity over time can predict future infections, and whether this pattern can distinguish between different sources of infection. The study population included 13,409 individuals nested in a larger population of birds that were closely monitored in zoological facilities for over 22 years (1992–2014). A retrospective cohort study design and social network connectivity were used to estimate the association between exposure to an infected bird, and development of mycobacteriosis. Avian mycobacteriosis was diagnosed from histopathology and network connectivity was defined by enclosure histories over discrete time periods. Single-variable and multivariable longitudinal, mixed effects logistic regression models examined whether exposure to infected birds, both directly- and indirectly-connected, was associated with development of mycobacteriosis at the next time step. Our adjusted model showed an increased odds of developing mycobacteriosis (odds ratio = 2.15; 95 % CI: 1.48−3.12; p < 0.001) for birds that were directly exposed (i.e., housed in the same aviary) to another infected bird, compared to those with no exposure. Exposure to a positive, indirectly-connected bird at a previous time step was independently associated with an increased risk of mycobacteriosis (odds ratio = 1.56; 95 % CI: 1.11−2.19). This association persisted in adjusted models even when the indirect contacts were housed in distinctly different aviaries and never had contact with the subject of interest or its environment. Adjusted, risk-stratified models further characterized the type of exposure that increased the risk of avian mycobacteriosis. Birds that were exposed in small aviaries were more likely to develop mycobacteriosis than those exposed in larger aviaries and those with no exposure. The lesion distribution and species of the contact (same species versus different species) were also significant predictors of disease risk. Some findings were sensitive to model variation of time divisions and initiation time. Our study shows avian mycobacteriosis spread through the social network in quantifiable and discernable patterns. We provide empirical evidence that a contagious process drives some of the observed infection, but we also show low transmissibility based on sustained patterns of low incidence over time even when large groups of birds are exposed. Targeted risk mitigation efforts based on the characteristics of the exposure may be effective at reducing risk of avian mycobacteriosis while enhancing population sustainability.

Molecular epidemiology of SARS-CoV-2 isolated from COVID-19 family clusters

BackgroundTransmission within families and multiple spike protein mutations have been associated with the rapid transmission of SARS-CoV-2. We aimed to: (1) describe full genome characterization of SARS-CoV-2 and correlate the sequences with epidemiological data within family clusters, and (2) conduct phylogenetic analysis of all samples from Yogyakarta and Central Java, Indonesia and other countries.MethodsThe study involved 17 patients with COVID-19, including two family clusters. We determined the full-genome sequences of SARS-CoV-2 using the Illumina MiSeq next-generation sequencer. Phylogenetic analysis was performed using a dataset of 142 full-genomes of SARS-CoV-2 from different regions.ResultsNinety-four SNPs were detected throughout the open reading frame (ORF) of SARS-CoV-2 samples with 58% (54/94) of the nucleic acid changes resulting in amino acid mutations. About 94% (16/17) of the virus samples showed D614G on spike protein and 56% of these (9/16) showed other various amino acid mutations on this protein, including L5F, V83L, V213A, W258R, Q677H, and N811I. The virus samples from family cluster-1 (n = 3) belong to the same clade GH, in which two were collected from deceased patients, and the other from the survived patient. All samples from this family cluster revealed a combination of spike protein mutations of D614G and V213A. Virus samples from family cluster-2 (n = 3) also belonged to the clade GH and showed other spike protein mutations of L5F alongside the D614G mutation.ConclusionsOur study is the first comprehensive report associating the full-genome sequences of SARS-CoV-2 with the epidemiological data within family clusters. Phylogenetic analysis revealed that the three viruses from family cluster-1 formed a monophyletic group, whereas viruses from family cluster-2 formed a polyphyletic group indicating there is the possibility of different sources of infection. This study highlights how the same spike protein mutations among members of the same family might show different disease outcomes.

Molecular Analysis of Hepatitis B Virus in Mothers-Children Pairs

ackground: Vertical transmission of Hepatitis B Virus (HBV) is the primary infection source for infants, but little is known on the proportion of children that have acquired HBV from their mothers. Objective: We investigated the relationship of HBV sequencing in HBVpositive children and their mothers and explored the HBV phylogenetic tree. Methods: Serum-extracted HBV-DNA from 38 individuals (13 children paired to nine mothers, 16 unpaired infected children) was amplified by polymerase chain reaction and the target region HBV surface glycoprotein (amino acids 40-171) was directly sequenced. Following editing and alignment of these sequences, phylogenetic tree analysis was performed using the neighbourjoining and maximum-likelihood methods. Results: Analysis was successfully performed in 29 subjects (23 children and six mothers), including six mother-child pairs. All individuals were infected by genotype D. Subgenotype adw3 prevailed (21, 72.4%), followed by ayw2 (4, 13.8%) and ayw3 (4, 13.8%). Among six mother-child pairs, three had identical and three had different subgenotypes. Phylogenetic analysis revealed that HBV sequences from three children did not cluster with their siblings suggesting a different source of infection. Conclusion: Our findings suggest that HBV subgenotypes in infected children may not be identical to their mothers’ and point to non-vertical HBV transmission in childhood.

Demographic Profiles and Sources of Infection among Septic Patients admitted at ICU of a Public Hospital in Dhaka City

Background: Sepsis occurs due to different sources of infection.&#x0D; Objective: The purpose of the present study was to see the demographic profiles and sources of infection among septic patients admitted at ICU of a public hospital in Dhaka City.&#x0D; Methodology: This descriptive cross sectional study was conducted in the Intensive Care Unit of the department of Anaesthesia Analgesia, Palliative and Intensive Care Medicine, Dhaka Medical College Hospital, Dhaka, Bangladesh over a period of 12 months starting from January 2016 to December 2016. All patients admitted to ICU with the features of severe sepsis and septic shock according to SSC guidelines with the age of more than or equal to 18 years in both sexes were set as selection criteria for this study. Instruments required to perform the study were data sheet addressing the demographic data, primary source of severe sepsis and organ dysfunctions. BSepsis was confirmed by detection of serum lactate and culture of blood.&#x0D; Result: A total number of patients was 69 cases. The mean with SD was 38.72 ±13.43 with the age range of patient 18 to 65 year. The male and female ratio was 1.7:1. The most common source of infection were abdomen which was 30(43.5%) cases followed by CNS, respiratory tract, urogenital tract and GIT which were (21.7%) cases, (14.5%) cases, (17.4%) cases and (2.9%) cases respectively. Among the 69 patient 20 patients were blood cultures positive, 15 patients were pus culture positive, 10 patients were urine/catheter tip culture positive.&#x0D; Conclusion: In conclusion young adult male is most commonly suffering from sepsis in ICU mostly due to infection of abdomen.&#x0D; Bangladesh Journal of Infectious Diseases 2020;7(2):40-43

The Epidemiology of Co-Infections in Febrile Children Younger than 5-Years-Old in Emergency Department; A Cross-Sectional Hospital-Based Study

Background Fever is one of the most common causes of children’s referral to pediatric emergency department (ED), and almost 20% of General ED referrals relate to febrile children. When it comes to febrile pediatrics patients, co-infection is a very important issue to discuss. This topic has been considered in current literature so, we considered to examine the epidemiology of these co-infections in febrile children younger than 5 years in emergency department. Materials and Methods: This cross-sectional study was carried out retrospectively with the enrollment of children younger than 5-years-old (accessible sampling) in the emergency department of Mofid Hospital, Tehran, Iran, during November 2017 to December 2018. After designing and completing a check list. Results: Totally, 388 patients with the mean age of 25.4 ± 12.4 months were studied (51.5% Girl). The source of infection was unclear after using all of the diagnostic tools in 27.5% of cases. Based on the findings fever-associated diarrhea (132 patients, 46.9%), and cellulitis (1 patient, 0.4%) were the most and least frequent source of infections, respectively. The co-incidence of different source of infections showed that the most frequent co-infections were sepsis and UTI; otitis and UTI; pneumonia and UTI; pneumonia and URI; and sepsis and otitis. Conclusion It seems that co-infections have been significantly increased in girls and in theage range of 6-36 months. The most and least prevalent infections were fever-associated diarrhea and cellulitis among the patients with at least one type of infection. The co-incidence of different source of infection showed that the most frequent co-infections were sepsis and UTI; otitis and UTI; pneumonia and UTI; pneumonia and URI; and sepsis and otitis.

Spatial Distribution of Serologically Reactive Sheep to Leptospira spp. in the Northeast Region of Brazil

Background: Considering the importance of leptospirosis in sheep farming and public health and the significance of identifying which serogroups circulate in sheep within each region, the objective of this study was to determine the seroprevalence and spatial distribution of the most frequent serogroups causing infection by Leptospira sp. in ovine herds in the Northeast region of Brazil.Materials, Methods &amp; Results: Blood samples were collected from 4197 sheep from 229 herds in 7 Northeastern States. Sera were analyzed via microscopic agglutination test (MAT). The frequency of seroreactive sheep for Leptospira sp. was 14.06%. The states of Alagoas, Ceará, Paraíba, Piauí, Rio Grande do Norte, and Sergipe, located in the Caatinga biome, had the highest frequencies of serologically reactive sheep, and Maranhão, in the Cerrado biome, had the lowest frequency. The most frequent serogroups were Autumnalis (19.49%), Australis (15.76%) and Serjoe (14.41%). In the states of Ceará, Paraíba, Rio Grande do Norte, and Sergipe, 100% of their municipalities had at least one seroreactive animal. The highest frequencies of seropositive animals were found in the municipalities of União (50%), Passagem (49.06%), Canindé (48.89%), Igaci (28.95%), Gararu (31.2%), Pirapemas (17.5%), and Angicos (16%) located in the states of Piauí, Paraíba, Ceará, Alagoas, Sergipe, Maranhão and Rio Grande do Norte, respectively.Discussion: The animal-level prevalence (14.06%) obtained in the present study is significant, especially considering the rustic nature of the species and the adverse conditions of the region for the infectious agent. In semi-arid conditions, it has been suggested that perhaps sheep do not seroconvert detectable titers on MAT with a cut-off point of 1:100. It is important to highlight that theovine population in the Northeast region of Brazil is composed of mixed animals, which have been considered more resistant to infection by Leptospira spp. Also, environmental factors hostile to the survival of the infectious agent in the studied region should be taken into consideration, since they may have influenced the seropositive animal-level prevalence. A noteworthy variation was observed in agglutinin titers, which ranged from 100 to 1,600, where 80.2% of the positive samples had titers ≤ 200. It is important to highlight that more elevated titers (≥ 400) were obtained in all seven states, which may suggest an acute infection caused by a non-adapted serovar, indicating that preventive and control measures focused on possible infection sources for sheep should be adopted. Although some states showed the same serogroups as the most frequent, a variety of serogroups was observed in municipalities, which may indicate different sources of infection, whether interspecies, intraspecies, or via alternative routes of transmission in semi-arid conditions, such as venereal. This indicates that even though sheep are more resistant to infection, they become exposed due to the environment or management conditions. As such, identification, isolation, and treatment of the affected animals are alternative measures recommended for prevention and control of leptospirosis in sheep in the semi-arid region. It is evident that despite the lack of rain observed in the last decade in the Northeast region of Brazil, which prevented the formation of favorable environments for the presence of Leptospira, the infectious agent remains among the sheep, as well as other production and wild animals in the region. Some factors may be contributing to this scenario, such as the fact that sheep farming in the region is characterized mainly by subsistence systems, where veterinary assistance and adequate sanitary management are absent, thus increasing the possibility of contact with Leptospira.Keywords: small ruminants, semi-arid, zoonosis.

Loranthus acaciae: Alternative medicine for β-lactamase producer and methicillin-resistant Staphylococcus aureus.

Recently, we reported high antibacterial efficiency of Loranthus acaciae (LA) against different standard strains of bacteria including Methicillin-Resistant Staphylococcus aureus (MRSA). Therefore, this study aimed to confirm the effectiveness of LA against clinically isolated Staphylococcus aureus (SA) including β-lactamase producer (Blac) and MRSA. Forty-eight SA isolates collected from various clinical samples were used in this study. Antibiotics susceptibility profile was determined for twenty different antibiotics using automated Microscan Walkaway 96 Plus system as recommended by Clinical and Laboratory Standards Institute (CLSI) guidelines. This system also identified β-lactamase producers and MRSA. In the meantime, LA ethanolic extract was fractionated using liquid–liquid fraction method to hexane, dichloromethane DCM and methanol 80% fractions. Antimicrobial activities of LA extract and fraction were performed with agar well diffusion method for all SA isolates, MIC and MBC were also recorded. Phytochemical screening for various phyto-constituent classes of LA ethanolic extract was determined. Out of 48 SA isolates, Cefoxitin-positive MRSA represent 31 (64.6%), Blac 17 (35.4%), and 41 (85.4%) were multidrug-resistant SA, which was resistant at least to one antibiotic from three different categories. All isolates were resistant to ampicillin and penicillin. Antimicrobial activities of LA extract and fractions revealed that ethanol extract was active against all isolated SA with inhibition zone ranged from 33 ± 2.00 to 25 ± 3.05 mm. While DCM exhibited the largest inhibition zone range from 37 ± 3.00 to 33 ± 2.00 mm. This study is first of its kind conforming the high antibacterial activity of LA against SA isolated from a different source of infection. The study concluded that LA extract and fractions are active and give positive result for all isolated SA. Therefore, suitable pharmacological formulation of LA extract as a promising antibacterial agent for the treatment of SA infection should be given extreme priority.

Progress on the incubation period of COVID-19

<p indent="0mm">Coronavirus disease 2019 (COVID-19) is an emerging infectious disease caused by SARS-CoV-2. Effective treatments are still lacking. The incubation period of COVID-19 is the period between the infection of an individual by a pathogen (SARS-CoV-2) and the manifestation of the illness or disease. The incubation period is one of the important epidemiological parameters of infectious diseases. The study of the incubation period of COVID-19 is of great significance for better understanding the natural history of the disease, tracing the source of infection, determining the detention, quarantine and isolation of contacts, determining the time of immunization, and making prevention and control measures. This study mainly reviews the progress of the incubation period of COVID-19. In previous studies, a direct calculation or parameter estimation method is usually used to estimate the incubation period, and the commonly used distributions are lognormal distribution, Weibull distribution, Gamma distribution, etc. Due to the differences in the study population, data sources and estimation methods, there are differences in the estimation results of the incubation period of COVID-19 in various studies. The estimated median incubation period for COVID-19 was about <sc>5.9 d</sc> (95%CI: 2.98−10.51) and the average incubation period was about <sc>5.7 d</sc> (95%CI: 4.3−8.9). The median incubation period for COVID-19 was estimated to be about <sc>5.2 d</sc> (95%CI: 3.0−11.9) in studies using the direct calculation method, and about <sc>5.25 d</sc> (95%CI: 3.57−8.19) in studies using the parameter estimation method. To calculate the incubation period of COVID-19, it is important to accurately collect the date of exposure and the date of symptoms onset. Due to the diversity of COVID-19 transmission routes and the possibility of multiple exposures to the same source of infection or to different sources of infection, it is often difficult to determine the exact exposure time for some patients, which brings the difficulty to the accurate estimation of the incubation period. The choice of methods depends on the epidemiological data of the study population and application scenarios. For example, in the early stage of an outbreak, when the incubation period data of small samples of infected persons are quickly obtained through field epidemiological investigation, it is advisable to adopt the direct calculation method for rapid estimation and timely guidance for prevention and control measures. As the epidemic progresses, when more epidemiological survey data are available, the parameter estimation method is a better choice. The optimal method can be selected for estimation. Either direct calculation or parameter estimation method, the accuracy of the data is crucial. Therefore, the recall bias should be minimized to obtain relatively accurate data at each key time point. At the same time, a more accurate estimate of the incubation period can be obtained by taking the infector-infected pairs with a clear transmission chain as the study population.

Metabolic profiling of Candida clinical isolates of different species and infection sources

Candida species are the most common cause of opportunistic fungal infections. Rapid identification and novel approaches for the characterization of these fungi are of great interest to improve the diagnosis and the knowledge about their pathogenic properties. This study aimed to characterize clinical isolates of Candida spp. by proteomics (MALDI-TOF MS) and metabolomics (1H-NMR), and to correlate their metabolic profiles with Candida species, source of infection and different virulence associated parameters. In particular, 49 Candida strains from different sources (blood, n = 15; vagina, n = 18; respiratory tract, n = 16), belonging mainly to C. albicans complex (61%), C. glabrata (20%) and C. parapsilosis (12%) species were used. Several extracellular and intracellular metabolites showed significantly different concentrations among isolates recovered from different sources of infection, as well as among different Candida species. These metabolites were mainly related to the glycolysis or gluconeogenesis, tricarboxylic acid cycle, nucleic acid synthesis and amino acid and lipid metabolism. Moreover, we found specific metabolic fingerprints associated with the ability to form biofilm, the antifungal resistance (i.e. caspofungin and fluconazole) and the production of secreted aspartyl proteinase. In conclusion, 1H-NMR-based metabolomics can be useful to deepen Candida spp. virulence and pathogenicity properties.

CLOSTRIDIAL MYCOTIC ANEURYSM LEADING TO EMPHYSEMATOUS AORTITIS: A CASE REPORT

SESSION TITLE: Medical Student/Resident Chest Infections Posters SESSION TYPE: Med Student/Res Case Rep Postr PRESENTED ON: October 18-21, 2020 INTRODUCTION: Emphysematous aortitis (EA) is a rare consequence of mycotic aneurysm associated with high morbidity and mortality. Most cases have been linked to infection with Staphylococcus species. This case reports clostridial bacteremia leading to arterial myonecrosis and subsequent aortitis. CASE PRESENTATION: The patient was a 66-year-old male with a past medical history of end stage renal disease with an arterio-venous fistula, hypertension, and diabetes who presented with tachycardia, tachypnea, and hypertension for one week. He also had leukocytosis of 23,000/µL with elevated inflammatory markers including a D-dimer of 4700 ng/mL. Computed tomography showed air within the walls of the thoracic aorta and in the periaortic soft tissue with extension from the aortic arch to the mid descending thoracic aorta consistent with aortitis. There was also involvement in the periaortic mediastinal fat and a loculated large left pleural effusion concerning for empyema. Blood cultures revealed Clostridium subterminale, however, gastrointestinal work up did not reveal esophageal or colonic malignancy, or mucosal trauma. He then underwent ascending aorta and distal arch reconstruction. Unfortunately, his post-operative course was complicated by hypotension unresponsive to multiple vasopressors and asystole. Post-mortem aortic tissue cultures were positive for Clostridium innocuum. DISCUSSION: EA is a rare but often fatal sequelae of mycotic aneurysms and has been hypothesized to occur through arterial injury (trauma), bacteremic seeding, contiguous infection, or septic emboli. Risk factors include arterial injury (Intravenous drug use/iatrogenic interventions), infection, immunosuppression, atherosclerosis, and pre-existing aneurysm. Mycotic aneurysms comprise only 0.5% to 1.3% of all aneurysms, and Clostridium species only comprise 0.7% of those cases. C. innocuum aortitis appears to present radiographically similar to other types of Clostridium aortic aneurysms, in which periaortic gas was found to be present in 92.6% of cases. Curiously, the patient was found to have bacteremia with a separate Clostridium species (C. subterminale) from the one found in the aortic wall (C. innocuum). Some reported cases of C. subterminale bacteremia was associated with mucosal damage. The patient’s negative endoscopy findings may suggest a different source of infection for both Clostridium species, possibly via the patient's arterio-venous fistula leading to infection within the atherosclerotic plaques of the aorta. CONCLUSIONS: Emphysematous aortitis is a rare complication of anaerobic infection. A high suspicion should be present in the differential based on radiographic and clinical findings as well as patient risk factors. Reference #1: Sörelius K, Budtz-Lilly J. Systematic Review of the Management of Mycotic Aortic Aneurysms. Eur J Vasc Endovasc Surg. 2019;58(3):426-435. doi:10.1016/j.ejvs.2019.05.004 Reference #2: Ito F, Inokuchi R, Matsumoto A, et al. Presence of periaortic gas in Clostridium septicuminfected aortic aneurysm AIDS in early diagnosis: A case report and systematic review of the literature. J Med Case Rep. 2017;11(1). doi:10.1186/s13256-017-1422-0 Reference #3: Seder CW, Kramer M, Long G, Uzieblo MR, Shanley CJ, Bove P. Clostridium septicum aortitis: Report of two cases and review of the literature. J Vasc Surg. 2009;49(5):1304- 1309. doi:10.1016/j.jvs.2008.11.058 DISCLOSURES: No relevant relationships by Thomas Ng, source=Web Response No relevant relationships by Christopher Pham, source=Web Response

Effects of seed infection and hydration on the buildup of common bacterial blight and its impact on the yield of dry beans

Common bacterial blight (CBB), caused by Xanthomonas axonopodis pv. phaseoli (Xap), is a serious foliar disease in most of the dry bean (Phaseolus vulgaris L.) growing regions. A 4 yr study examined the effects of different sources of infection and seed hydration on CBB development, yield components, and yield in seven resistant or susceptible dry bean lines and cultivars. The five agronomic treatments examined included clean seed, diseased seed, hydrated diseased seed, clean seed with a Xap spray, and diseased seed with a Xap spray. Disease development, the yield components, and yield were strongly influenced by weather conditions. In comparison with the diseased-seed treatment, the use of clean (disease-free) seed reduced the incidence of CBB leaf infection in the susceptible dry bean cultivars, but no similar benefit was observed in the resistant lines and cultivars. During the three dry growing seasons, the seed-hydration treatment increased the incidence of CBB leaf infection compared with the diseased-seed treatment for the susceptible cultivars but not for the resistant lines and cultivars. In the wet growing season, no significant difference in the incidence of leaf infection was observed between the hydrated-seed and diseased-seed treatments in any of the cultivars, possibly because the wet soil conditions promoted pathogen development within the bean plants that year. Seed hydration did not improve seed yield in the dry years, but sometimes decreased it under wet conditions. Therefore, seed hydration cannot be recommended for use in the production of dry beans.