Search

Background: De-regulated host response to severe coronavirus disease 2019 (COVID-19), directly referring to the concept of sepsis-associated immunological dysregulation, seems to be a strong signature of severe COVID-19. Myeloid cells phenotyping is well recognized to diagnose critical illness-induced immunodepression in sepsis and has not been well characterized in COVID-19. The aim of this study is to review phenotypic characteristics of myeloid cells and evaluate their relations with the occurrence of secondary infection and mortality in patients with COVID-19 admitted in an intensive care unit. Methods: Retrospective analysis of the circulating myeloid cells phenotypes of adult COVID-19 critically ill patients. Phenotyping circulating immune cells was performed by flow cytometry daily for routine analysis and twice weekly for lymphocytes and monocytes subpopulations analysis, as well as monocyte human leukocyte antigen (mHLA)-DR expression. Results: Out of the 29 critically ill adult patients with severe COVID-19 analyzed, 12 (41.4%) developed secondary infection and six patients died during their stay. Monocyte HLA-DR kinetics was significantly different between patients developing secondary infection and those without, respectively, at day 5–7 and 8–10 following admission. The monocytes myeloid-derived suppressor cells to total monocytes ratio was associated with 28- and 60-day mortality. Those myeloid characteristics suggest three phenotypes: hyperactivated monocyte/macrophage is significantly associated with mortality, whereas persistent immunodepression is associated with secondary infection occurrence compared to transient immunodepression. Conclusions: Myeloid phenotypes of critically ill COVID-19 patients may be associated with development of secondary infection, 28- and 60-day mortality. [ABSTRACT FROM AUTHOR]

In recent years, more and more studies have shown that early pathogenic bacterial infection in invertebrates can enhance immunity and significantly reduce mortality when reinfected with the same pathogen. There are mechanisms to explain this phenomenon, but they are relatively few. In addition, dose-dependent primary infection is also associated with increased immunity. In the present study, the initial infection dose and mortality of abalone Haliotis diversicolor after reinfection with Vibrio harveyi were recorded, and the mechanism of immune enhancement was investigated by the transcriptomic response of abalone after two successive stimuli with V. harveyi. Priming with different concentrations of pathogen can enhance immunity; however, higher concentration is not always better. Compared with the first exposure, more genes were up-regulated after the second exposure. Among the commonly expressed genes, the immune related genes were significantly or persistently highly expressed after two infections and included pattern recognition receptors as well as immune effectors, such as toll-like receptors, perlucin 4, scavenger receptor class B-like protein, cytochrome P450 1B1-like, glutathione S-transferase 6, lysozyme and so on; in addition, these immune-related genes were mainly distributed in the pathways related to phagocytosis and calcium signaling. Among the specifically expressed genes, compared with the first infection, more genes were involved in the immune, metabolic and digestive pathways after the second infection, which would be more conducive to preventing the invasion of pathogens. This study outlined the mechanism of immune enhancement in abalone after secondary infection at the global molecular level, which is helpful for a comprehensive understanding of the mechanism of immune priming in invertebrates. [ABSTRACT FROM AUTHOR]

Background: Co‐infections, secondary bacterial or fungal infections, are important risk factors for poor outcomes in viral infections. The prevalence of co‐infection and secondary infection in patients infected with SARS‐CoV‐2 is not well understood. Aims: To investigate the role of co‐infections and secondary infections in disease severity of hospitalized individuals with COVID‐19. Materials and Methods: A retrospective study was carried out between 11 January 2020 and 1 March 2020 among 408 laboratory confirmed COVID‐19 patients in China. These patients were divided into three groups based on disease severity: mild or moderate, severe, or critically ill. Microbiological pathogens in blood, urine, and respiratory tract specimens were detected by the combination of culture, serology, polymerase chain reaction, and metagenomic next‐generation sequencing (mNGS). Results: The median age of participants was 48 years (IQR 34–60 years). Fifty‐two patients (12.7%) had at least one additional pathogen, 8.1% were co‐infected, and 5.1% had a secondary infection. There were 13 Mycoplasma pneumoniae cases, 8 Haemophilus influenzae cases, 8 respiratory viruses, and 3 Streptococcus pneumoniae cases, primarily detected in mild and moderate COVID‐19 patients. Hospital‐acquired infection pathogens were more common in critically ill patients. Compared to those without additional pathogens, patients with co‐infections and/or secondary infections were more likely to receive antibiotics (p < 0.001) and have elevated levels of d‐dimer (p = 0.0012), interleukin‐6 (p = 0.0027), and procalcitonin (p = 0.0002). The performance of conventional culture was comparable with that of mNGS in diagnosis of secondary infections. Conclusion: Co‐infections and secondary infections existed in hospitalized COVID‐19 patients and were relevant to the disease severity. Screening of common respiratory pathogens and hospital infection control should be strengthened. [ABSTRACT FROM AUTHOR]

Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfections have been reported; however, most cases are milder than the primary infection. We report the first case of a life-threatening critical presentation of a SARS-CoV-2 reinfection. Methods A 62-year-old man from Palamós (Spain) suffered a first mild coronavirus disease 2019 (COVID-19) episode in March 2020, confirmed by 2 independent SARS-CoV-2 nasopharyngeal polymerase chain reaction (PCR) assays and a normal radiograph. He recovered completely and tested negative on 2 consecutive PCRs. In August 2020, the patient developed a second SARS-CoV-2 infection with life-threatening bilateral pneumonia and Acute respiratory distress syndrome criteria, requiring COVID-19–specific treatment (remdesivir + dexamethasone) plus high-flow oxygen therapy. Nasopharyngeal swabs from the second episode were obtained for virus quantification by real-time PCR, for virus outgrowth and sequencing. In addition, plasma and peripheral blood mononuclear cells during the hospitalization period were used to determine SARS-CoV-2–specific humoral and T-cell responses. Results Genomic analysis of SARS-CoV-2 showed that the virus had probably originated shortly before symptom onset. When the reinfection occurred, the subject showed a weak immune response, with marginal humoral and specific T-cell responses against SARS-CoV-2. All antibody isotypes tested as well as SARS-CoV-2 neutralizing antibodies increased sharply after day 8 postsymptoms. A slight increase of T-cell responses was observed at day 19 after symptom onset. Conclusions The reinfection was firmly documented and occurred in the absence of robust preexisting humoral and cellular immunity. SARS-CoV-2 immunity in some subjects is unprotective and/or short-lived; therefore, SARS-CoV-2 vaccine schedules inducing long-term immunity will be required to bring the pandemic under control. [ABSTRACT FROM AUTHOR]

A 37-year-old healthcare worker from the northeastern region of Brazil experienced 2 clinical episodes of coronavirus disease. Infection with severe acute respiratory syndrome coronavirus 2 was confirmed by reverse transcription PCR in samples collected 116 days apart. Whole-genome sequencing revealed that the 2 infections were caused by the most prevalent lineage in Brazil, B.1.1.33, and the emerging lineage P.2. The first infection occurred in June 2020; Bayesian analysis suggests reinfection at some point during September 14-October 11, 2020, a few days before the second episode of coronavirus disease. Of note, P.2 corresponds to an emergent viral lineage in Brazil that contains the mutation E484K in the spike protein. The P.2 lineage was initially detected in the state of Rio de Janeiro, and since then it has been found throughout the country. Our findings suggest not only a reinfection case but also geographic dissemination of the emerging Brazil clade P.2. [ABSTRACT FROM AUTHOR]

In this paper, a non-linear stage-structured model has been formulated to study the effects of primary/secondary dengue infection on children and adults. It is assumed that a proportion of susceptible children have been previously infected by a serotype asymptomatically. After recovery from asymptomatic infection, the immunity is developed for the particular serotype but they remain susceptible to heterologous serotypes. These children may get secondary infection when exposed to a different serotype. The model has two equilibrium states. Global/local stability of equilibrium states have been discussed. The stability of disease-free state changes at R 0 = 1 . Applying the center manifold theory, the existence of forward bifurcation is possible. This concludes that the primary/secondary infection in children as well as in adults population could be eradicated for R 0 < 1 . Numerical results are used to explore the global behavior of disease-free/endemic state for choice of arbitrary initial conditions. [ABSTRACT FROM AUTHOR]

We seek to investigate the multifaceted factors influencing secondary infections in patients with multidrug-resistant Gram-negative bacteria (MDR-GNB) colonization or infection post-hospitalization. A total of 100 patients with MDR-GNB colonization or infection were retrospectively reviewed, encompassing those admitted to both the general ward and intensive care unit of our hospital from August 2021 to December 2022. Patients were categorized into the control group (non-nosocomial infection, n = 56) and the observation group (nosocomial infection, n = 44) based on the occurrence of nosocomial infection during hospitalization. Clinical data were compared between the two groups, including the distribution and antibiotic sensitivity of MDR-GNB before nosocomial infection. Significant differences were observed between the two groups in terms of age, underlying diseases, immune status, length of stay, and invasive medical procedures (P < 0.05). The observation group also had fewer patients practicing optimized hygiene, strict isolation, and antibiotic control than the control group (P < 0.05). Factors influencing the risk of secondary infection after hospitalization in patients colonized or infected with MDR-GNB included patient age, underlying diseases, immune status, length of hospitalization, medical invasive procedures, optimized hygiene, strict isolation, and antibiotic control (P < 0.05). The length of hospitalization and treatment cost in the observation group were higher than those in the control group (P < 0.05). This study comprehensively analyzes the intricate mechanisms of secondary infections in patients with MDR-GNB infections post-hospitalization. Key factors influencing infection risk include patient age, underlying diseases, immune status, length of hospitalization, medical invasive procedures, optimized hygiene, strict isolation, and antibiotic control. • Insights into the mechanisms of MDR-GNB infection. • Immunocompromised elderly patients are vulnerable for MDR-GNB infection. • Strengthening isolation, antibiotic control reduce incidence of MDR-GNB infection. • The long term MDR-GNB infections lead to escalated treatment costs. [ABSTRACT FROM AUTHOR]

Summary: Background: The cause of pericarditis is manifold. It can occur as a result of various diseases but may also be triggered by drugs. However, the data on drug-induced pericarditis are still scarce. Case report: A 64-year-old female hypertensive patient with rheumatoid arthritis for 20 years presented with thoracic pain and recurrent pericardial and pleural effusions. For treatment of the recurrent effusions, the patient received glucocorticoids and colchicine in addition to the basic rheumatoid arthritis therapy, and treatment has only recently been expanded to include etanercept. On admission, she complained of malaise, dysphagia, and blood pressure was 85/55 mm Hg. She was normofrequent with elevated inflammatory parameters. On trans-thoracal echocardiography (TTE) and computer-tomography (CT), there was a 3-cm non-floating structure in the entire circumference of the pericardium. The indication for pericardiectomy was given because of hemodynamic impairment. After incision of the pericardium, 250 ml of a brown-reddish fluid drained, with brown crumbly necrotic masses visible underneath. Histopathologic findings revealed vasculitis-related chronic fibrinous pericarditis with vasculitic changes. A subclinical infection with Staphylococcus aureus was detectable by PCR analysis. Conclusion: Based on the fact that tumor necrosis factor blockers can induce vasculitis, etanercept might have been responsible for the exacerbation of pericarditis. The underlying rheumatoid arthritis could also be considered as a trigger. The detection of Staphylococcus aureus DNA in the pericardium and the exacerbation of pericarditis could be attributed to secondary vasculitis after an infection with S. aureus, whereas the tendency to infection due to humoral immunodeficiency after years of immunosuppressive therapy has to be discussed as a trigger. [ABSTRACT FROM AUTHOR]

Abstract Background Secondary infection has a higher incidence in septic patients and affects clinical outcomes. This study aims to investigate the clinical characteristics, risk factors, immune status and prognosis of secondary infection of sepsis. Methods A four-year retrospective study was carried out in Zhongshan Hospital, Fudan University, enrolling septic patients admitted between January, 2014 and January, 2018. Clinical data were acquired from medical records. CD14+ monocyte human leukocyte antigen-D related (HLA-DR) expression and serum cytokines levels were measured by flow cytometry and enzyme-linked immunosorbent assay (ELISA) respectively. Results A total of 297 septic patients were enrolled, 92 of whom developed 150 cases of secondary infections. Respiratory tract was the most common site of secondary infection (n = 84, 56%) and Acinetobacter baumanii the most commonly isolated pathogen (n = 40, 31%). Urinary and deep venous catheterization increased the risk of secondary infection. Lower HLA-DR expression and elevated IL-10 level were found in secondary infection group. The expected prolonged in-hospital stay owing to secondary infection was 4.63 ± 1.87 days. Secondary infection was also associated with higher in-hospital, 30-day and 90-day mortality. Kaplan-Meier survival analysis and Log-rank test revealed that secondary infection group had worse survival between day 15 and day 90. Conclusions Urinary and deep venous catheterization increased the risk of secondary infection, in which underlying immunosuppression might also play a role. Secondary infection affected the prognosis of septic patients and prolonged in-hospital length of stay.

A SEIARN compartment model with the asymptomatic infection and secondary infection is proposed to predict the trend of COVID-19 more accurately. The model is extended according to the propagation characteristics of the novel coronavirus, the concepts of the asymptomatic infected compartment and secondary infection are introduced, and the contact rate parameters of the improved model are updated in real time by using the LSTM trajectory, in order to make accurate predictions. This SEIARN model first builds on the traditional SEIR compartment model, taking into account the asymptomatic infection compartment and secondary infection. Secondly, it considers the disorder of the trajectory and uses the improved LSTM model to predict the future trajectory of the current patients and cross-track with the susceptible patients to obtain the contact rate. Then, we conduct real-time updating of exposure rates in the SEIARN model and simulation of epidemic trends in Tianjin, Xi’an, and Shijiazhuang. Finally, the comparison experiments show that the SEIARN model performs better in prediction accuracy, MSE, and RMSE.

Defined as helpful live bacteria that can provide medical advantages to the host when administered in tolerable amounts, oral probiotics might be worth considering as a possible preventive or therapeutic modality to mitigate coronavirus disease 2019 (COVID-19) symptom severity. This hypothesis stems from an emerging understanding of the gut–lung axis wherein probiotic microbial species in the digestive tract can influence systemic immunity, lung immunity, and possibly viral pathogenesis and secondary infection co-morbidities. We review the principles underlying the gut–lung axis, examples of probiotic-associated antiviral activities, and current clinical trials in COVID-19 based on oral probiotics.

Chemotherapy is accompanied by suppression of the immune system of a patient, which is usually handled through the judicial use of antibiotic therapy. Through clinical conditions like granulocytopenia, antibiotic treatment is given along with chemotherapeutic drugs. Granulocytopenic infection, which is associated with three bacteria, i.e., Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa, causes the granulocyte count to fall below 500/mm3, thereby causing complications and resulting in the death of cancer patients. In this study, one-pot synthesis is used to incorporate the anticancer and antibiotic drugs into silver nanoparticles by using a chemical reduction method. The morphological data indicate the size of ampicillin-mediated silver nanoparticles (i.e., Amp-Ag NPs) as ~ 25 nm, which further, after adding paclitaxel (i.e., AT-Ag NPs) in the reaction mixture, increase to ~ 42 nm. The antimicrobial studies of synthesized NPs show a synergistic effect toward the infection-causing bacteria. Imaging studies represent the accumulation of nanoparticles and pores formation into the bacterial membrane. Biological assay and apoptosis assay predict the positive efficacy of paclitaxel, keeping the therapy intact. Hence, the robust drug delivery system in cancer therapy with minimal side effects and improved antimicrobial and anticancer activity is proposed. [ABSTRACT FROM AUTHOR]

Introduction: Immunosuppressive agents are theorized to target the cytokine storm syndrome in COVID-19. However, the downstream effects regarding susceptibilities to secondary infection risk remains unknown. This study seeks to determine risk differences for secondary infections among COVID-19 patients who did and did not receive tocilizumab. Methods: We conducted a matched retrospective cohort study from two large, acute care hospitals in Western Connecticut from March 1, to May 31, 2020. We collected variables using manual medical record abstraction. The primary exposure variable was any dose of tocilizumab. The primary outcome was any healthcare-associated bacterial or fungal infection as defined by the National Healthcare Safety Network. We performed a Kaplan–Meier analysis to assess the crude difference in cumulative probability of healthcare-associated infection (HAI) across exposure groups. We also performed a multivariable Cox regression analysis to determine the hazard ratio for HAI by exposure group while controlling for potential confounders. Results: The Kaplan–Meier analysis demonstrated no difference in the cumulative probability of HAI across groups. The adjusted hazard of HAI for patients given tocilizumab was 0.85 times that of patients not given tocilizumab (95% confidence interval = 0.29, 2.52, P = 0.780) after controlling for relevant confounders. Conclusions: Tocilizumab did not increase the incidence of secondary infection among COVID-19 patients. Larger, randomized trials should evaluate infection as a secondary outcome to validate this finding. [ABSTRACT FROM AUTHOR]

A highly adaptive and exquisitely complex immune system allows for these functions and responds to repel infection as well as repair severe injury from trauma or sepsis ([1], [2]). Keywords: immunity; inflammation; secondary infection; sepsis; trauma EN immunity inflammation secondary infection sepsis trauma 691 693 3 03/28/22 20220401 NES 220401 Anesthesia/Critical Care medicine, Neurology, Neurosurgery, and General Internal Medicine Johns Hopkins School of Medicine, Baltimore, MD *See also p. 565. These data are the first systemic observational data in severe acute injury including sepsis, suggesting that acute injury alters the immune response and may predispose to potential later infection. [Extracted from the article]

Objectives: Thrombocytopenia is common in critically ill patients treated with continuous renal replacement therapy and decreases in platelets following continuous renal replacement therapy initiation have been associated with increased mortality. Platelets play a role in innate and adaptive immunity, making it plausible that decreases in platelets following continuous renal replacement therapy initiation predispose patients to development of infection. Our objective was to determine if greater decreases in platelets following continuous renal replacement therapy correlate with increased rates of secondary infection.Design: Retrospectivecohort analysis.Setting: This study uses a continuous renal replacement therapy database from Mayo Clinic (Rochester, MN), a tertiary academic center.Participants: Adult patients who survived until ICU discharge and were on continuous renal replacement therapy for less than 30 days were included. A subgroup analysis was also performed in patients with thrombocytopenia (platelets < 100 × 103/µL) at continuous renal replacement therapy initiation.Measurements and Main Results: The primary predictor variable was a decrease in platelets from precontinuous renal replacement therapy levels of greater than 40% or less than or equal to 40%, although multiple cut points were analyzed. The primary outcome was infection after ICU discharge, and secondary endpoints included post-ICU septic shock and post-ICU mortality. Univariable, multivariable, and propensity-adjusted analyses were used to determine associations between the predictor variable and the outcomes.Results: Among 797 eligible patients, 253 had thrombocytopenia at continuous renal replacement therapy initiation. A greater than 40% decrease in platelets after continuous renal replacement therapy initiation was associated in the multivariable-adjusted models with increased odds of post-ICU infection in the full cohort (odds ratio, 1.49; CI, 1.02-2.16) and in the thrombocytopenia cohort (odds ratio, 2.63; CI, 1.35-5.15) cohorts.Conclusions: Platelet count drop by greater than 40% following continuous renal replacement therapy initiation is associated with an increased risk of secondary infection, particularly in patients with thrombocytopenia at the time of continuous renal replacement therapy initiation. Further research is needed to evaluate the impact of both continuous renal replacement therapy and platelet loss on subsequent infection risk. [ABSTRACT FROM AUTHOR]

Background: Buruli ulcer (BU) is a skin disease caused by Mycobacterium ulcerans and is the second most common mycobacterial disease after tuberculosis in Ghana and Côte d'Ivoire. M. ulcerans produces mycolactone, an immunosuppressant macrolide toxin, responsible for the characteristic painless nature of the infection. Secondary infection of ulcers before, during and after treatment has been associated with delayed wound healing and resistance to streptomycin and rifampicin. However, not much is known of the bacteria causing these infections as well as antimicrobial drugs for treating the secondary microorganism. This study sought to identify secondary microbial infections in BU lesions and to determine their levels of antibiotic resistance due to the prolonged antibiotic therapy required for Buruli ulcer. Results: Swabs from fifty-one suspected BU cases were sampled in the Amansie Central District from St. Peters Hospital (Jacobu) and through an active case surveillance. Forty of the samples were M. ulcerans (BU) positive. Secondary bacteria were identified in all sampled lesions (N = 51). The predominant bacteria identified in both BU and Non-BU groups were Staphylococci spp and Bacilli spp. The most diverse secondary bacteria were detected among BU patients who were not yet on antibiotic treatment. Fungal species identified were Candida spp, Penicillium spp and Trichodema spp. Selected secondary bacteria isolates were all susceptible to clarithromycin and amikacin among both BU and Non-BU patients. Majority, however, had high resistance to streptomycin. Conclusions: Microorganisms other than M. ulcerans colonize and proliferate on BU lesions. Secondary microorganisms of BU wounds were mainly Staphylococcus spp, Bacillus spp and Pseudomonas spp. These secondary microorganisms were less predominant in BU patients under treatment compared to those without treatment. The delay in healing that are experienced by some BU patients could be as a result of these bacteria and fungi colonizing and proliferating in BU lesions. Clarithromycin and amikacin are likely suitable drugs for clearance of secondary infection of Buruli ulcer. [ABSTRACT FROM AUTHOR]

Introduction: Novel Coronavirus outbreak has posed a global threat. While the infection appears to be mild in most patients, considering its high rate of transmission, a large number of people are at risk of developing severe to critical illness in total which makes prognosis studies a priority. The aim of the present study was to evaluate red blood cell distribution width (RDW) as a predictive factor for diagnosing severe cases of coronavirus disease 2019 (COVID-19). Materials and Methods: A total number of 204 inpatients diagnosed with COVID-19 including 122 men and 82 women (Mean age: 58.83±15.93 years old) treated at Imam Reza Hospital, Mashhad, Iran were included in the study. Patients were divided into severe and moderate groups according to their clinical signs and examinations and pulmonary imaging features. Demographic Data, laboratory test results, treatments, patients' complications and outcome were recorded. Mann-Whitney U test and spearman correlation coefficient (r) were performed to assess RDW correlation with severity and serious complications in patients including intensive care unit (ICU) admission, shock, secondary infections, intubation, length of hospitalization and death. Receiver operating characteristics (ROC) curves analysis was carried out to define the reliability of RDW as a predictive indicator in severe COVID-19. Results: The results showed statistical significant correlations between high levels of RDW and developing secondary infections and longer hospitalization (P values =0.001). The optimal cutoff for RDW to predict the length of hospitalization (= 7 days or more than 7 days) was estimated to be 14.65% with 94% sensitivity and 71.3% speciJicity. The area under curve was calculated to be 0.895 through Roc curve analysis. Conclusion: High predictive value of RDW, a routine blood test parameter, could be used in diagnosing COVID-19 patients at higher risk for developing secondary infections and longer hospital stay which in turn helps with better management of the disease. [ABSTRACT FROM AUTHOR]

Background: Salmonella is a major food-borne bacterial pathogen that causes food poisoning related to the consumption of eggs, milk, and meat. Food safety in relation to Salmonella is particularly important for eggs because their shells as well as their contents can be a source of contamination. Chicken can also be infected with influenza virus, but it remains unclear how co-infection of Salmonella and influenza virus affect each other., Aim: The potential influence of co-infection of Salmonella and influenza virus was examined., Methods: Salmonella Abony and influenza virus were injected into chicken embryonated eggs. After incubation, proliferation of Salmonella and influenza virus was measured using a direct culture assay for bacteria and an enzyme-linked immunosorbent assay for influenza virus, respectively., Results: Our findings indicate that the number of colony-forming units (CFUs) of Salmonella did not vary between chicken embryonated eggs co-infected with influenza A virus and Salmonella -only infected eggs. Furthermore, we found the proliferation of influenza A or B virus was not significantly influenced by co-infection of the eggs with Salmonella ., Conclusion: These results suggest that combined infection of Salmonella with influenza virus does not affect each other, at least in terms of their proliferation., Competing Interests: The Author declares that there is no conflict of interest.

Bacterial co-pathogens are commonly identified in viral respiratory infections and are important causes of morbidity and mortality. The prevalence of bacterial infection in patients infected with SARS-CoV-2 is not well understood. To determine the prevalence of bacterial co-infection (at presentation) and secondary infection (after presentation) in patients with COVID-19. We performed a systematic search of MEDLINE, OVID Epub and EMBASE databases for English language literature from 2019 to April 16, 2020. Studies were included if they (a) evaluated patients with confirmed COVID-19 and (b) reported the prevalence of acute bacterial infection. Data were extracted by a single reviewer and cross-checked by a second reviewer. The main outcome was the proportion of COVID-19 patients with an acute bacterial infection. Any bacteria detected from non-respiratory-tract or non-bloodstream sources were excluded. Of 1308 studies screened, 24 were eligible and included in the rapid review representing 3338 patients with COVID-19 evaluated for acute bacterial infection. In the meta-analysis, bacterial co-infection (estimated on presentation) was identified in 3.5% of patients (95%CI 0.4–6.7%) and secondary bacterial infection in 14.3% of patients (95%CI 9.6–18.9%). The overall proportion of COVID-19 patients with bacterial infection was 6.9% (95%CI 4.3–9.5%). Bacterial infection was more common in critically ill patients (8.1%, 95%CI 2.3–13.8%). The majority of patients with COVID-19 received antibiotics (71.9%, 95%CI 56.1 to 87.7%). Bacterial co-infection is relatively infrequent in hospitalized patients with COVID-19. The majority of these patients may not require empirical antibacterial treatment. Image 1 [ABSTRACT FROM AUTHOR]

Secondary methicillin‐resistant Staphylococcus aureus (MRSA) infection is a cause of severe pneumonia with high mortality during influenza A virus (IAV) pandemics. Alveolar macrophages (AMs) mount cellular defenses against IAV and MRSA infection, which occurs via the nucleotide‐binding domain‐like receptor protein 3 (NLRP3) inflammasome. However, the activity and function of the NLRP3 inflammasome in MRSA pneumonia secondary to IAV infection remain unclear. To clarify this, we studied MRSA infection secondary to IAV both in vitro and in mouse model. The expression of the NLRP3 inflammasome was evaluated by quantitative reverse transcription polymerase chain reaction, immunofluorescence, Western blot, and enzyme‐linked immunosorbent assay. The lung pathology and the rate of weight change were observed. We found that IAV infection for 1 week activated NLRP3 inflammasome. The enhanced expression of NLRP3, caspase‐1, and cleaved caspase‐1 was associated with MRSA infection secondary to IAV, but the expression of interleukin (IL)‐1β decreased in superinfection with MRSA both in vitro and in vivo. The aggravated inflammatory pathology in MRSA pneumonia secondary to IAV infection was associated with decreased expression of IL‐1β. And increased weight loss in MRSA pneumonia secondary to IAV infection was related to decreased concentration of IL‐1β in serum. It infers that superinfection with MRSA reduces expression of IL‐1β someway, and decreased expression of IL‐1β impairs the host immunity and leads to aggravated pneumonia. These results contributed to our understanding of the detailed activity of the NLRP3 inflammasome, IL‐1β, and their relationship with aggravation of MRSA pneumonia secondary to IAV infection. Immunotherapy targeting the IL‐1β signaling pathway could be possible therapeutic strategy for secondary MRSA pneumonia. Highlights: MRSA pneumonia secondary to influenza A virus infection causes severe outcome.NLRP3 inflammasome plays a role in the pathogenesis of MRSA pneumonia secondary to IAV infection.The aggravated inflammatory pathology in MRSA pneumonia secondary to IAV infection was associated with decreased expression of IL‐1β.Immunotherapy targeting the NLRP3 inflammasome and IL‐1β signaling pathway could be possible therapeutic strategy for secondary MRSA pneumonia. [ABSTRACT FROM AUTHOR]

H9N2 avian influenza virus (AIV) infection in chickens is often accompanied by secondary bacterial infection, but the mechanism is unclear. The aim of the present study was to reveal that mechanism and explore non-antibiotic treatment. 16s rRNA sequencing and metabonomics were performed in the intestinal contents of chickens infected with H9N2 AIV or H9N2 AIV and fed with ageratum-liquid (AL) to reveal the metabolite that promote intestinal Escherichia coli (E. coli) proliferation caused by H9N2 AIV, as well as to determine the regulatory effect of AL. It was found that H9N2 AIV infection led E. coli to become the dominant gut microbe and promoted E. coli translocation from the intestinal tract to the visceral tissue through the damaged intestinal barrier. H9N2 AIV infection induces inflammation in the intestinal mucosa and promotes the secretion and release of nitrate from the host intestinal epithelium. In addition, nitrate promoted E. coli proliferation in the inflamed intestinal tract following H9N2 AIV infection. Furthermore, Chinese herbal medicine AL can restore intestinal homeostasis, inhibit the production of nitrate in the intestinal epithelium and effectively prevent the proliferation and translocation of E. coli in the intestines. This is the first report on the mechanism of E. coli secondary infection induced by H9N2 AIV, where herbal medicine AL was shown to have a good preventive effect on the secondary infection.

Dengue virus (DENV) is the most common and widespread arboviral infection worldwide. Though all four DENV serotypes cocirculate in nature, the clinicopathological framework of these serotypes is undefined in Pakistan. A cross-sectional, observational study was performed to document the circulation of various arboviruses in the Sindh region of Pakistan. Here we describe a population of patients diagnosed with DENV spanning a 2-year period. This study used an orthogonal system of NS1 antigen ELISA followed by RT-PCR for DENV detection and subtyping. A total of 168 NS1 positive patients were evaluated of which 91 patients were serotyped via RT-PCR. There was no significant difference between sex or age for infection risk and peak transmission occurred during the Autumn months. DENV2 was the most common serotype followed by DENV1 then DENV3, then DENV4. The data show that DENV1 patients were more likely to have abnormal liver function tests; DENV2 infected patients were more likely to exhibit arthralgia and neurological symptoms; DENV3 patients were more likely to complain of burning micturition and have elevated lymphocyte counts and low hematocrit; and DENV4 patients were more likely to report headaches and rash. Notably, no dengue hemorrhagic fever or other manifestations of severe dengue fever were present in patients with primary or secondary infections. We were able to identify significantly more NS1 antigen positive patients than RT-PCR. This study demonstrates that all four DENV serotypes are co-circulating and co-infecting in Pakistan.

We previously reported that NK cells can promote type 1 T cell immune response that is essential for protection to a primary infection of Chlamydia muridarum. In this study, we have investigated the contribution of NK cells to memory T cells associated immunity during chlamydial infection. We have found that NK cell depletion led to impaired production of IFN-γ by memory T cells upon re-stimulation with chlamydial antigens in vitro. Mice with depleted NK cells also exhibited reduced type 1 T cell recall responses, with increased production of IL-4 from CD4+ T cells and a lower level of Chlamydia-specific IgG2a titers compared to control mice. In addition, Tregs response was significantly increased in mice with NK cell depletion. Moreover, NK cell-depleted mice showed an increased bacterial loads and more severe inflammatory pathological changes than control mice. These findings indicate that NK cells contribute to protective memory T cell associated immunity to chlamydial re-infection through modulating the cytokine pattern of T cell and inhibition of Tregs response.

Sepsis is characterized by a systemic inflammation that can cause an immune dysfunction, for which the underlying mechanisms are unclear. We investigated the impact of cecal ligature and puncture (CLP)-mediated polymicrobial sepsis on monocyte (Mo) mobilization and functions. Our results show that CLP led to two consecutive phases of Mo deployment. The first one occurred within the first 3 days after the induction of the peritonitis, while the second phase was of a larger amplitude and extended up to a month after apparent clinical recovery. The latter was associated with the expansion of Mo in the tissue reservoirs (bone marrow and spleen), their release in the blood and their accumulation in the vasculature of peripheral non-lymphoid tissues. It occurred even after antibiotic treatment but relied on inflammatory-dependent pathways and inversely correlated with increased susceptibility and severity to a secondary infection. The intravascular lung Mo displayed limited activation capacity, impaired phagocytic functions and failed to transfer efficient protection against a secondary infection into monocytopenic CCR2-deficient mice. In conclusion, our work unveiled key dysfunctions of intravascular inflammatory Mo during the recovery phase of sepsis and provided new insights to improve patient protection against secondary infections.

Acute pancreatitis (AP) is considered a cascade of immune responses triggered by acinar cell necrosis. AP involves two main processes of systemic inflammatory response syndrome and subsequent compensatory anti-inflammatory response syndrome. Although great efforts have been made regarding AP therapy, the mortality rate of AP remains high. Secondary infection acts a lethal factor in AP. Lymphocytes act as major immune mediators in immune responses in the course of this disease. However, the relationship between lymphocytes and secondary infection in AP is unclear. This review summarizes the variation of lymphocytes and infection in AP. Knowledge of the characterization of circulating lymphocyte abnormalities is relevant for understanding the pathophysiology of AP.

Abstract Background The use of probiotics to improve anti-microbial defence, such as for influenza infections, is increasingly recommended. However, no data are available on the effect of probiotics on flu-associated secondary bacterial infections. There is strong evidence of a spatiotemporal association between influenza virus infection and invasive Neisseria meningitidis. We thus investigated the effect of feeding mice Lactobacillus paracasei CNCM I-1518 in a mouse model of sequential influenza-meningococcal infection. Methods We intranasally infected BALB/c mice with a strain of influenza A virus (IAV) H3N2 that was first adapted to mice. Seven days later, a secondary bacterial infection was induced by intranasal administration of bioluminescent N. meningitidis. During the experiment, mice orally received either L. paracasei CNCM I-1518 or PBS as a control. The effect of L. paracasei administration on secondary bacterial infection by N. meningitidis was evaluated. Results Oral consumption of L. paracasei CNCM I-1518 reduced the weight loss of infected mice and lowered the bioluminescent signal of infecting meningococci. This improvement was associated with higher recruitment of inflammatory myeloid cells, such as interstitial monocytes and dendritic cells, to the lungs. Conclusions Our data highlight the role of the gut-lung axis. L. paracasei CNCM I-1518 may boost the defence against IAV infection and secondary bacterial infection, which should be further studied and validated in clinical trials.

Dengue Virus Infections are distributed in tropical and sub-tropical regions and transmitted by the mosquitoes such as Aedes aegypti and Aedes albopictus. Dengue virus can cause dengue fever, dengue hemorrhagic fever and dengue shock syndrome or dengue and severe dengue classified by World Health Organization. Beside it concurrent infection virus salmonella had been found some cases who showed fever more than 7 days. Concurrent infection with two agents can result in an illness having overlapping symptoms creating a diagnostic dilemma for treating physician, such as dengue fever with typhoid fever. The aim of this research is detection of dengue virus and secondary infection with Salmonella typhi in patients suspected dengue virus infection. Detection of dengue virus and Salmonella typhi using immunochromatography test such as NS1, IgG/IgM for dengue virus infection, and IgM/IgG Salmonella and blood culture. The fifty children with dengue virus infection came to Soerya hospital and 17 cases suspected dengue virus infection, five cases showed a positive NS1 on the second day of fever and one case concurrent with clinical manifestation of convulsi on the third days of fever there were five cases only showed positive. It was showed in this study that on the fourth to six day of fever in dengue virus infection accompanied by antibody IgM & IgG dengue. There were 12 cases showed the clinical manifestation of concurrent dengue viral infection and Salmonella, all of them showed a mild clinical manifestation and did not show plasma leakage and shock. In this study we found the length of stay of concurrent Dengue Virus Infection and Salmonella infection is more than 10 days. These patients were also more likely to have co-existing haemodynamic disturbances and bacterial septicaemia which would have required treatment with inotropes and antibiotics. This idea is very important to make update dengue viral management to decrease mortality in outbreak try to gain new prevention method before the occurrence of outbreak.

• Secondary infections prevail in North Vietnamese adults with few cases of severe disease. • Dengue virus serotypes DENV1 and DENV2 are predominant with higher viremia in primary infection than secondary infection. • Adult secondary dengue infection is distinguished by IgM:IgG ratio cut off <0.7. • Platelet loss correlates with dengue-specific IgG and IgM levels but does not necessarily lead to longer hospital stay or worsening illness. • Platelet autoantibodies in acute dengue infection and autoimmune complications in post-dengue warrant further investigation. The morbidity in dengue fever is dependent on the dengue virus (DENV) serotypes, the patient age, predisposing immunogenic markers and the frequency of primary and secondary infections. This study aims to distinguish acute primary from secondary dengue infections of Vietnamese adults and to assess the association of viremia and anti-dengue immunoglobulin levels with clinical outcomes. Viral RNA, dengue serotypes and levels of anti-dengue IgM and IgG of hospitalized adult cases were determined in EDTA-plasma samples prospectively collected during three consecutive years of dengue infection in Hanoi. Patients admitted to hospital within 7 days of their 1st reported fever were included. Primary infections were anti-dengue IgG enzyme-linked immunosorbent assay (ELISA) negative on both day of hospital entry (day 0) and day two or three of hospitalization (day 2 or 3) with a positive anti-dengue IgM on either day 0 or day 2 or 3 hospitalization. The secondary infections were anti-dengue IgG ELISA positive on both day 0 and day 2 or 3 with positive anti-dengue IgM ELISA on either day 0 or day 2 or 3. The hospitalized dengue fever cases between October 2016 and March 2019 were predominantly secondary infections (74%, 68% and 77%, respectively) with DENV-1 (60% and 65%) and DENV-2 (22% and 26%) serotypes determined in the latter two years. The viremia in primary infection was significantly higher than that in secondary infection (P < 0.01) and positively correlated with the days of hospital stay. In secondary infections, platelet counts were lower than in primary infections (P = 0.04) and IgG levels in secondary infection negatively correlated with platelet counts (Spearman's r = −0.22, P < 0.01). Our results indicate high rates of secondary infection with DENV1 and DENV2 serotypes. Anti-dengue immunoglobulins negatively correlate with hospital stay and platelet counts with few warning signs or severe disease. Further investigations of specific antibodies in adults which predict auto-inflammatory activity after the recovery from dengue infection are warranted. [ABSTRACT FROM AUTHOR]

H9N2 avian influenza virus (AIV) infection in chickens is often accompanied by secondary bacterial infection, but the mechanism is unclear. The aim of the present study was to reveal that mechanism and explore non-antibiotic treatment. 16s rRNA sequencing and metabonomics were performed in the intestinal contents of chickens infected with H9N2 AIV or H9N2 AIV and fed with ageratum-liquid (AL) to reveal the metabolite that promote intestinal Escherichia coli (E. coli) proliferation caused by H9N2 AIV, as well as to determine the regulatory effect of AL. It was found that H9N2 AIV infection led E. coli to become the dominant gut microbe and promoted E. coli translocation from the intestinal tract to the visceral tissue through the damaged intestinal barrier. H9N2 AIV infection induces inflammation in the intestinal mucosa and promotes the secretion and release of nitrate from the host intestinal epithelium. In addition, nitrate promoted E. coli proliferation in the inflamed intestinal tract following H9N2 AIV infection. Furthermore, Chinese herbal medicine AL can restore intestinal homeostasis, inhibit the production of nitrate in the intestinal epithelium and effectively prevent the proliferation and translocation of E. coli in the intestines. This is the first report on the mechanism of E. coli secondary infection induced by H9N2 AIV, where herbal medicine AL was shown to have a good preventive effect on the secondary infection. [ABSTRACT FROM AUTHOR]

Infections with any pathogen can be severe and present with numerous complications caused by the pathogen or the host immune response to the invading microbe. However, coinfections, also called polymicrobial infections or secondary infections, can further exacerbate disease. Coinfections are more common than is often appreciated. In this review, we focus specifically on coinfections between viruses and other viruses, bacteria, parasites, or fungi. Importantly, innate immune signaling and innate immune cells that facilitate clearance of the initial viral infection can affect host susceptibility to coinfections. Understanding these immune imbalances may facilitate better diagnosis, prevention, and treatment of such coinfections. [ABSTRACT FROM AUTHOR]

This manuscript aims to highlight the risk of Ventilator-Associated Bacterial Pneumonia (VAP) in COVID-19 inpatients. The co-infection has the potential to worsen clinical condition and increase mortality in these patients, as well as to prolong and increase the costs of hospitalization. Preventing, identifying and treating early VAP can increase the chances of successful treatment in patients with COVID-19. [ABSTRACT FROM AUTHOR]

This article reports on the management of a large median symmetrical lesion of the anterior palate, which was clinically and radiographically diagnosed as an infected nasopalatine duct cyst. However, histopathology demonstrated it to be a radicular cyst of endodontic origin. [ABSTRACT FROM AUTHOR]

Background: Secondary infection is an important factor affecting mortality and quality of life in patients with severe acute pancreatitis. The characteristics of secondary infection, which are well known to clinicians, need to be re-examined in detail, and their understanding among clinicians needs to be updated accordingly.Aim: This study aims to investigate the characteristics and drug resistance of pathogens causing severe acute pancreatitis (SAP) secondary infection, to objectively present infection situation, and to provide reference for improved clinical management.Methods: A retrospective analysis was performed on 55 consecutive patients with SAP who developed secondary infection with an accurate evidence of bacterial/fungal culture from 2016 to 2018. The statistics included the spectrum and distribution of pathogens, the drug resistance of main pathogens, and associations between multiple infectious parameters and mortality.Results: A total of 181 strains of pathogens were isolated from (peri)pancreas; bloodstream; and respiratory, urinary, and biliary systems in 55 patients. The strains included 98 g-negative bacteria, 58 g-positive bacteria, and 25 fungi. Bloodstream infection (36.5%) was the most frequent infectious complication, followed by (peri)pancreatic infection (32.0%). Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, and Stenotrophomonas maltophilia were predominant among gram-negative bacteria. Gram-positive bacterial infections were mainly caused by Enterococcus faecium and Staphylococcus spp. Fungal infections were predominantly caused by Candida spp. The drug resistance of pathogens causing SAP secondary infection was generally higher than the surveillance level. Patients in the death group were older (55 ± 13 years vs. 46 ± 14 years; p = 0.039) and had longer intensive care unit (ICU) stay (14 vs. 8; p = 0.026) than those in the survival group. A. baumannii infection (68.4% vs. 33%; p = 0.013), number of pathogens ≥ 4 (10 vs. 6; p = 0.005), pancreatic infection (14 vs. 15, p = 0.024), and urinary infection (8 vs. 5; p = 0.019) were significantly associated with mortality.Conclusion: Gram-negative bacteria are the main pathogens causing SAP secondary infection, in which nosocomial infections play a major role. The drug resistance profile of gram-negative bacteria is seriously threatening, and the commonly used antibiotics in SAP are gradually losing their effectiveness. Much attention should be paid to the rational use of antibiotics, and strategies should be established for infection prevention in SAP. [ABSTRACT FROM AUTHOR]

The current fatality of dengue among the Bangladeshi population has drawn the interest of the public health professionals primarily to focus on the environmental, social, and clinical reasoning as well the possible remedies. This year, in 2019, the dengue situation in Bangladesh has appeared with all its dreadful effects leading to the highest death cases due to dengue virus (DENV) infection. According to the Directorate General of Health Services report, this year (2019) the number of DENV-infected people has appeared to be around five times higher (approximately 50,000 cases so far) compared with the last year, 2018 (around 10,000 cases). The present review discussed the current epidemics of dengue infection in Bangladesh as well the possible means of disease curing in terms of general preventive concepts. However, besides the precise treatment of the dengue-affected patients, the knowledge on DENV genome and on the protective immunity against such reemerging disease is essential. [ABSTRACT FROM AUTHOR]

In this paper, a nonlinear vector-host model has been proposed and analyzed for the two dengue serotypes incorporating ADE effect. The model considers that the asymptomatic infected people are more responsible for secondary infection than that of symptomatic ones and differentiates between them. The existence and stability analysis have been performed for various equilibrium states. Basic reproduction number is found to be directly proportional to ADE parameter. This means that increasing ADE parameter increases the basic reproduction number which not only enhances the severity of serotype-1 free state but also destabilizes the disease-free state. Numerical simulation has been carried out for the stability of endemic state and found to be locally stable for choice of initial conditions in its neighborhood. The persistence of disease in periodic form is also obtained for a suitable choice of data. Sensitivity analysis has been performed with respect to transmission parameters involved in basic reproduction number. [ABSTRACT FROM AUTHOR]

We previously reported that NK cells can promote type 1 T cell immune response that is essential for protection to a primary infection of Chlamydia muridarum. In this study, we have investigated the contribution of NK cells to memory T cells associated immunity during chlamydial infection. We have found that NK cell depletion led to impaired production of IFN-γ by memory T cells upon re-stimulation with chlamydial antigens in vitro. Mice with depleted NK cells also exhibited reduced type 1 T cell recall responses, with increased production of IL-4 from CD4+ T cells and a lower level of Chlamydia -specific IgG2a titers compared to control mice. In addition, Tregs response was significantly increased in mice with NK cell depletion. Moreover, NK cell-depleted mice showed an increased bacterial loads and more severe inflammatory pathological changes than control mice. These findings indicate that NK cells contribute to protective memory T cell associated immunity to chlamydial re-infection through modulating the cytokine pattern of T cell and inhibition of Tregs response. [ABSTRACT FROM AUTHOR]

Sepsis is characterized by a systemic inflammation that can cause an immune dysfunction, for which the underlying mechanisms are unclear. We investigated the impact of cecal ligature and puncture (CLP)-mediated polymicrobial sepsis on monocyte (Mo) mobilization and functions. Our results show that CLP led to two consecutive phases of Mo deployment. The first one occurred within the first 3 days after the induction of the peritonitis, while the second phase was of a larger amplitude and extended up to a month after apparent clinical recovery. The latter was associated with the expansion of Mo in the tissue reservoirs (bone marrow and spleen), their release in the blood and their accumulation in the vasculature of peripheral non-lymphoid tissues. It occurred even after antibiotic treatment but relied on inflammatory-dependent pathways and inversely correlated with increased susceptibility and severity to a secondary infection. The intravascular lung Mo displayed limited activation capacity, impaired phagocytic functions and failed to transfer efficient protection against a secondary infection into monocytopenic CCR2-deficient mice. In conclusion, our work unveiled key dysfunctions of intravascular inflammatory Mo during the recovery phase of sepsis and provided new insights to improve patient protection against secondary infections. [ABSTRACT FROM AUTHOR]

Dengue fever is a common disease which can cause shock, internal bleeding, and death in patients if a second infection is involved. In this paper, a multi-serotype dengue model with nonlinear incidence rate is formulated to study the transmission of two dengue serotypes. The dynamical behaviors of the proposed model depend on the threshold value R 0 n known as the reproductive number which depends on the associated reproductive numbers with serotype-1 and serotype-2. The value of R 0 n is used to reflect whether the disease dies out or becomes endemic. It is found that the proposed model has a globally stable disease-free equilibrium if R 0 n ≤ 1 , which indicates that if public health measures that make (and keep) the threshold to a value less than unity are carried out, the strategy in disease control is effective in the sense that the number of infected human and mosquito populations in the community will be brought to zero irrespective of the initial sizes of sub-populations. When R 0 n > 1 , the endemic equilibria called the co-existence primary and secondary infection equilibria are locally asymptotically stable. The effects of cross immunity and nonlinear incidence rate are explored using data from Thailand to determine the effective strategy in controlling and preventing dengue transmission and reinfection. [ABSTRACT FROM AUTHOR]

Acute pancreatitis (AP) is considered a cascade of immune responses triggered by acinar cell necrosis. AP involves two main processes of systemic inflammatory response syndrome and subsequent compensatory anti-inflammatory response syndrome. Although great efforts have been made regarding AP therapy, the mortality rate of AP remains high. Secondary infection acts a lethal factor in AP. Lymphocytes act as major immune mediators in immune responses in the course of this disease. However, the relationship between lymphocytes and secondary infection in AP is unclear. This review summarizes the variation of lymphocytes and infection in AP. Knowledge of the characterization of circulating lymphocyte abnormalities is relevant for understanding the pathophysiology of AP. [ABSTRACT FROM AUTHOR]

Objectives: We reported tet(S/M) in Streptococcus pneumoniae and investigated its temporal spread in relation to nationwide clinical interventions.Methods: We whole-genome sequenced 12 254 pneumococcal isolates from 29 countries on an Illumina HiSeq sequencer. Serotype, multilocus ST and antibiotic resistance were inferred from genomes. An SNP tree was built using Gubbins. Temporal spread was reconstructed using a birth-death model.Results: We identified tet(S/M) in 131 pneumococcal isolates and none carried other known tet genes. Tetracycline susceptibility testing results were available for 121 tet(S/M)-positive isolates and all were resistant. A majority (74%) of tet(S/M)-positive isolates were from South Africa and caused invasive diseases among young children (59% HIV positive, where HIV status was available). All but two tet(S/M)-positive isolates belonged to clonal complex (CC) 230. A global phylogeny of CC230 (n=389) revealed that tet(S/M)-positive isolates formed a sublineage predicted to exhibit resistance to penicillin, co-trimoxazole, erythromycin and tetracycline. The birth-death model detected an unrecognized outbreak of this sublineage in South Africa between 2000 and 2004 with expected secondary infections (effective reproductive number, R) of ∼2.5. R declined to ∼1.0 in 2005 and <1.0 in 2012. The declining epidemic could be related to improved access to ART in 2004 and introduction of pneumococcal conjugate vaccine (PCV) in 2009. Capsular switching from vaccine serotype 14 to non-vaccine serotype 23A was observed within the sublineage.Conclusions: The prevalence of tet(S/M) in pneumococci was low and its dissemination was due to an unrecognized outbreak of CC230 in South Africa. Capsular switching in this MDR sublineage highlighted its potential to continue to cause disease in the post-PCV13 era. [ABSTRACT FROM AUTHOR]

Background: Atopic eczema is a relapsing, itchy chronic cutaneous inflammatory disease that commonly affects children. The disease is often complicated by cutaneous infections such as eczema herpeticum, eczema vaccinatum and a varied number of bacterial infections - impetigo, cellulitis and erysipelas. However, rare case reports of infective endocarditis, otitis media and osteo-articular infections have been associated with atopic eczema. These associations possibly represent the extracutaneous infectious complications of atopic eczema.Case Presentation: Here we present two cases of osteomyelitis in HIV negative children with habitual scratching of poorly managed and/or uncontrolled atopic eczema respectively. Both cases presented to the orthopaedic surgeons and were admitted as acute phalangeal osteomyelitis and acute - on - chronic tibial osteomyelitis respectively. The first case was an 8 year old girl who had moderate-severe poorly-controlled atopic eczema and contiguously spread phalangeal osteomyelitis. The second case was an 11 year old pre-pubertal boy who had untreated atopic eczema and tibial osteomyelitis possibly from haematogenously spread Staphylococcus aureus infection. Both were successfully discharged from hospital and currently have well controlled eczema. The 11 year old patient is also being reviewed monthly by the orthopaedic surgeons and is chronic suppressive antibiotics. He may require sequestrectomy, should it be needed.Conclusions: Invasive staphylococcal and streptococcal osteo-articular (OA) infection can arise as an extra-cutaneous infectious complication of poorly controlled atopic eczema. It is more common in the 3 to 15 year age group and especially in boys with a septic arthritis to osteomyelitis ratio of around 29:5. Clinicians should maintain a high index of suspicion in patients with moderate-severe atopic eczema and they ought to promptly manage these OA infections with intravenous antibiotics to avoid further complications. [ABSTRACT FROM AUTHOR]

Microbes are the main cause of caries. Once these microbes reaches pulp if the tooth has to be saved endodontic treatment is the only option. If the treatment is not initiated microbes can reach the periapical region and cause apical periodontitis and abscess. Proper understanding of the microbes that cause pulpal infection and pain will aid in bringing down the infection. This article discusses about the microbes that cause pulpal infection. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate the various etiological causes of secondary infection in acute conjunctivitis epidemic Materials & Methods: Prospective study of 100 patients with acute conjunctivitis presented to Govt Regional Eye Hospital Warangal. Age, sex occupation, residence, eye effected were noted. The patients were subjected to conjunctival swabbing with 2 swabs , each one for smear and staining and other for culture. For isolation and identification of organisms various culture media are used. Results: This series comprises of 100 patients with acute conjunctivitis. Out of 100 patients maximum incidence that is 33% of the affected patients were between 20-30 years. Male were 54% and females were 46%. 28% of the patients were Housewives, with 77% of the infection acquired from an affected family member. No geographic predisposition was found and 41% belonged to Warangal. 59% of the patients had involvement of both the eyes, and 78% had Moderate severity. 21% of the cases had 100% of the family members being affected. The most common complaints were Redness, Watering of the eyes. The smears revealed either No organism, / Gram -ve Diplococci / Gram +ve Bacilli / Gram +ve Cocci/Gram +ve diplococci / Gram –ve Bacilli / Diphtheroids. In the cultures, 7 of them grew Proteus with an average CFU / mL of 17 and 4 grew Diptheroids with an average CFU/mL of 24, 9 grew Aerobic Spore Bearers, 6 grew Micrococci with an average CFU/mL of 72, 3 were contamination. Rest of the 71 swabs grew no growth on culture, with the smears showing plenty to no pus cells and No organism. Conclusion: The study has revealed in majority of no secondary bacterial infection. Few cases are associated with secondary infection with various organisms. Out of which the Proteus is seen in majority of cases, which itself is not a normal resident flora in the conjunctiva. Due to the local decrease in Immunity may be the reason for access to the various organism to cause for secondary infection in Epidemic kerato conjuctivitis

The literature review focuses on the effect of forest soil properties on infection of coniferous trees and stumps by Heterobasidion spores and further growth of mycelium from tree to tree. Spread of the fungus is greater in alkaline soil. Forest plantations on former agricultural lands have an increased risk of infection, due to lack of antagonistic soil microorganisms. In Latvia, severe infection of spruce stands by Heterobasidion root rot has been observed on peat soils. [ABSTRACT FROM AUTHOR]

Chronic pain that arises or persists after endodontic treatment is an undesirable condition that requires proper diagnosis in order to be adequately approached. Some so-called 'mysterious' cases are usually related to limited knowledge or clinical inexperience, but inadequacies of diagnostic tools can also lead to misdiagnosis and confusion. The main causes of chronic post-treatment pain not always promptly recognised are outlined in this paper and include: i) persistent/secondary intraradicular infection; ii) persistent inflammation-undetected lesion; iii) unnoticed overfilling; iv) missed canals; v) vertical root fracture or crack; vi) wrong tooth; vii) non-odontogenic pain; and viii) central sensitisation (risk factors: preoperative pain, previous painful treatment). By having all of these possible causes in mind, clinicians may create a checklist for the possible reason(s) for pain in difficult individual cases and act proactively to offer the best therapeutic solution. [ABSTRACT FROM AUTHOR]

• Esketamine reduced splenomegaly and prevented secondary LPS-induced inflammation and cognitive deficits after primary LPS exposure. • The study highlighted the significant roles of the spleen and subdiaphragmatic vagus nerve in mediating secondary infection-induced inflammation and cognitive dysfunction. • Esketamine's protective effects were attributed to its modulation of the intestinal flora/subdiaphragmatic vagus nerve/spleen axis and enhancement of hippocampal BDNF levels. Susceptibility to secondary infection often increases after primary infection. Secondary infections can lead to more severe inflammatory injuries; however, the underlying mechanisms are not yet fully elucidated. To investigate whether esketamine treatment immediately after primary lipopolysaccharide (LPS) exposure could alleviate cognitive impairment caused by secondary infection. Mice were injected intraperitoneally (IP) with LPS (5 mg/kg) 10 days apart. Esketamine (10, 15, or 30 mg/kg) was administered IP immediately after the primary LPS injection. Splenectomy or subdiaphragmatic vagotomy (SDV) was performed 7 days before secondary LPS exposure or broad-spectrum antibiotic administration. Splenomegaly was observed after the primary LPS injection on Days 3 and 10. Splenomegaly was attenuated by treatment with 30 mg/kg esketamine. Esketamine treatment prevented increased plasma proinflammatory cytokines levels and cognitive dysfunction induced by secondary LPS exposure. Mice that underwent splenectomy or SDV had lower proinflammatory cytokines levels, higher hippocampal brain-derived neurotrophic factor (BDNF) levels, and improved cognitive function 1 day after secondary infection, which was not further improved by esketamine. Fecal microbiota transplantation (FMT) from endotoxic mice treated with esketamine attenuated hippocampal BDNF downregulation and cognitive dysfunction only in pseudo germ-free (PGF) mice without splenectomy. FMT with fecal suspensions from esketamine-treated endotoxic mice abrogated splenomegaly only in PGF mice without SDV. Blocking BDNF signaling blocked esketamine's ameliorating effects on secondary LPS exposure-induced cognitive dysfunction. The intestinal flora/subdiaphragmatic vagus nerve/spleen axis-mediated hippocampal BDNF downregulation significantly affected secondary LPS-induced systemic inflammation and cognitive dysfunction. Esketamine preserves cognitive function via this mechanism. [ABSTRACT FROM AUTHOR]

The complex innate immune defense of Biomphalaria glabrata , the intermediate host of Schistosoma mansoni , governs the successful development of the intramolluscan stages of the parasite. The interaction between the snail and the parasite involves a complex immune molecular crosstalk between several parasite antigens and the snail immune recognition receptors, evoking different signals and effector molecules. This work seeks to discuss the immune-related molecules that influence compatibility in Biomphalaria glabrata / Schistosoma mansoni interaction and the differential expression of these molecules between resistant and susceptible snails. It also includes the current understanding of the immune molecular determinants that govern the compatibility in sympatric and allopatric interactions, and the expression of these molecules after immune priming and the secondary immune response. Herein, the differences in the immune-related molecules in the interaction of other Biomphalaria species with Schistosoma mansoni compared to the Biomphalaria glabrata model snail are highlighted. Understanding the diverse immune molecular determinants in the snail/schistosome interaction can lead to alternative control strategies for schistosomiasis. [Display omitted] • The review is about the immune molecules in B. glabrata / S. mansoni interaction. • Differential expression of immune molecules between resistant/susceptible B. glabrata. • Immune molecules govern the compatibility in sympatric and allopatric interactions. • Different immune molecules in primary and secondary B. glabrata infection. • Immune molecules in the interaction of other Biomphalaria species with S. mansoni. [ABSTRACT FROM AUTHOR]