Acute Stage Of Infection Research Articles

COVID-19 Infection in Academic Dental Hospital Personnel; A Cross-Sectional Survey in Saudi Arabia.

Background: Close patient contact is an essential component of clinical dental education, which can expose students and faculty to risk of COVID-19 and its sequelae. Methods: The study was a cross-sectional survey conducted among faculty and clinical students at an academic dental hospital in Al Madinah western Saudi Arabia. An online questionnaire was distributed to collect data on prevalence, risk factors, clinical manifestations, and long-term health and socioeconomic complications of COVID-19 infection. Results: Prevalence of COVID-19 was 19.6% among a total of 316 students and faculty. Participants cited family and friends as the primary source of infection (40.3%). Among cross-infection control practices, they cited failure to practice distancing as the primary reason for infection transmission (61.3%). The disease was symptomatic in 85.5% of infected personnel. Most frequently reported clinical manifestations were: fever, cough, malaise, and diarrhoea (74.1%, 56.5%, 40.3%, 32.3%, respectively). A proportion of 37.1% of infected personnel stated that they had long COVID-19, and 58.3% of infected students reported deteriorated academic achievement. Conclusions: One in five of clinical dental students and their faculty had COVID-19. Most cases were symptomatic, and a large proportion developed long COVID or adverse socioeconomic consequences. Regardless of the severity of symptoms encountered during the acute stage of COVID-19 infection, all infected dental healthcare personnel should be followed, especially those who report long COVID. Continuous follow-up and assistance for infected students may be warranted to mitigate the potential academic and mental drawbacks caused by the pandemic. Dental schools should adopt clear policies regarding COVID-19 transmission and prevention and should implement them in their infection-control education and training.

Starving for nutrients: anorexia during infection with parasites in broilers is affected by diet composition

In 2 experiments, we investigated whether diet composition plays a role in pathogen-induced anorexia, the voluntary reduction in ADFI during infection in broilers. We hypothesized that either energy or CP dietary content could influence the extent of anorexia in Ross 308 broilers and infection outcomes with Eimeria maxima. From d 13 of age, half of the birds were infected, and half were uninfected. ADFI was measured daily, and BW every 3 d until d 29. Oocyst excretion was measured daily from d 17 to 23. The impact of parasitism on the small intestine was assessed on d 19 and 25. In Experiment 1, 336 birds were offered diets progressively diluted with lignocellulose, starting from a diet with 3,105 (kcal ME/kg) and 20% CP. There was a significant interaction between infection and diet on ADFI during the acute stage of infection (d 17 to 21): for control birds diet dilution decreased ADFI and consequently reduced energy and CP intake. For infected birds, diet dilution increased ADFI, leading to the same energy and CP intake across diets. Oocyst excretion and villi length to crypt depth ratio (VCR) were constant across infected treatments. In Experiment 2, 432 birds were offered diets with constant ME (3,105 kcal/kg), but different CP contents (24, 20, 26, and 12%). Infection significantly reduced ADFI. Although there was no interaction between infection and diet on ADFI, there was an interaction on CP intake during the acute stage of infection. Infected birds on the 20% CP diet achieved the same CP intake as uninfected birds. There were no differences in the VCR and ADG of the infected birds on 24, 20 and 16% CP treatments, but birds on 12% had the lowest ADG and excreted more oocysts. We suggest that during infection, birds target a nutrient resource intake, which appears to be beneficial for infection outcomes, while at the same time they avoid excess protein intake. We conclude that different mechanisms regulate ADFI in infected and uninfected birds.

Dramatic transcriptomic differences in Macaca mulatta and Macaca fascicularis with Plasmodium knowlesi infections

Plasmodium knowlesi, a model malaria parasite, is responsible for a significant portion of zoonotic malaria cases in Southeast Asia and must be controlled to avoid disease severity and fatalities. However, little is known about the host-parasite interactions and molecular mechanisms in play during the course of P. knowlesi malaria infections, which also may be relevant across Plasmodium species. Here we contrast P. knowlesi sporozoite-initiated infections in Macaca mulatta and Macaca fascicularis using whole blood RNA-sequencing and transcriptomic analysis. These macaque hosts are evolutionarily close, yet malaria-naïve M. mulatta will succumb to blood-stage infection without treatment, whereas malaria-naïve M. fascicularis controls parasitemia without treatment. This comparative analysis reveals transcriptomic differences as early as the liver phase of infection, in the form of signaling pathways that are activated in M. fascicularis, but not M. mulatta. Additionally, while most immune responses are initially similar during the acute stage of the blood infection, significant differences arise subsequently. The observed differences point to prolonged inflammation and anti-inflammatory effects of IL10 in M. mulatta, while M. fascicularis undergoes a transcriptional makeover towards cell proliferation, consistent with its recovery. Together, these findings suggest that timely detection of P. knowlesi in M. fascicularis, coupled with control of inflammation while initiating the replenishment of key cell populations, helps contain the infection. Overall, this study points to specific genes and pathways that could be investigated as a basis for new drug targets that support recovery from acute malaria.

A review on Infectious Coryza in Chickens: Emergence, Diagnostic Tools, Prophylaxis and Therapy

Haemophilus paragallinarum (H. paragallinarum) or Avibacterium paragallinarum (A. paragallinarum) is a Gram-negative bacterium causing infectious coryza (IC) in chickens. Infectious coryza is an acute upper respiratory infection that causes significant economic and productivity losses worldwide. Despite the use of prophylactic measures and treatment, the infection persists due to antibiotic resistance and a superior advantage in its outer protective antigen, resulting in a complicated disease pattern. Definitive diagnosis of the disease is hindered due to major challenges that are related to the complicated bacteriological isolation of the bacterium, which could be isolated only during the acute stage of infection, in addition to the fastidious and slow growth pattern of the organism. Egypt, as a key supporter of the chicken sector, is constantly threatened by this insidious infection, necessitating the development of new technology to combat it. The significance of A. paragallinarum infection, the prevalence of serotypes, clinical signs, characterization, diagnostic tools, prophylactic approaches, and therapies are discussed in this review. This article aims to provide more knowledge about the disease organism, newer diagnostic and therapeutic techniques for efficient containment of the organism therefore reducing the disease's negative economic impact.

CXCL17 Is Dispensable during Hypervirulent Mycobacterium tuberculosis HN878 Infection in Mice.

CXCL17 is a novel mucosal chemokine that mediates myeloid cell recruitment and bactericidal activity and highly expressed in the respiratory tract. However, its role in tuberculosis (TB) immunopathogenesis or protection remains unknown. In this study, we evaluated the function of CXCL17 in a mouse model of aerosol infection with the clinical W-Beijing lineage Mycobacterium tuberculosis hypervirulent HN878 strain. Our results show that CXCL17 production increases in the lung of M. tuberculosis–infected mice during acute and chronic stages of infection. Moreover, in vitro M. tuberculosis infection of epithelial cells and myeloid cells induces production of CXCL17. In humans, lower serum CXCL17 levels are observed among active pulmonary TB patients when compared with subjects with latent TB infection and healthy controls, suggesting a protective role. However, mice treated with rCXCL17 show similar lung bacterial burden and inflammation compared with control animals, despite an increased lung myeloid cell accumulation. Finally, CXCL17−/− mice are not more susceptible to TB than wild-type animals. These findings suggest that CXCL17 is induced in both murine epithelial and myeloid cells upon M. tuberculosis infection and increased expression during human latent TB infection. However, CXCL17 may have a dispensable role during pulmonary TB.

Rapid Clinical Progression and Its Correlates Among Acute HIV Infected Men Who Have Sex With Men in China： Findings From a 5-Year Multicenter Prospective Cohort Study.

BackgroundIn the “treat all” era, there are few data on the nature of HIV clinical progression in middle-income countries. The aim of the current study was to prospectively analyze the clinical progression of HIV and its indicators among men in China with acute HIV who have sex with men.MethodsFrom 2009–2014 a total of 400 men with acute HIV infection (AHI) were identified among 7,893 men who have sex with men via periodic pooled nucleic acid amplification testing, and they were assigned to an AHI prospective cohort in Beijing and Shenyang, China. Rapid progression was defined as two consecutive CD4+ T cell counts < 350/µL within 3–24 months post-infection. Kaplan−Meier and Cox-regression analyses were conducted to identify predictors of rapid progression.ResultsAmong 400 men with AHI 46.5% were rapid progressors, 35.1% reached rapid progressor status by 12 months post-infection, and 63.9% reached rapid progressor status by 24 months. Rapid progression was associated with herpes simplex-2 virus coinfection (adjusted hazard ratio [aHR] 1.7, 95% confidence interval [CI] 1.2–2.3], depression (aHR 1.9, 95% CI 1.5–2.6), baseline CD4+ T cell count < 500/μL (aHR 3.5, 95% CI 2.4–5.1), higher baseline HIV viral load (aHR 1.6, 95% CI 1.2–2.3), acute symptoms lasting ≥ 2 weeks (aHR 1.6, 95% CI 1.1–2.2), higher body mass index (aHR 0.9, 95% CI 0.9–1.0), higher HIV viral load (aHR 1.7, 95% CI 1.4–2.1), set point viral load at 3 months (aHR 2.0, 95% CI 1.6–2.5), each 100-cell/μL decrease in CD4+ T cell count at 3 months (aHR 2.2, 95% CI 1.9–2.5), and baseline routine blood tests including white blood cell count < 5.32, hemoglobin ≥ 151, mean corpuscular hemoglobin ≥ 30.5, hemoglobin concentration ≥ 342, mean platelet count ≥ 342, lymphocytes ≥ 1.98, and mixed cell count ≥ 0.4 (all p < 0.05).ConclusionAlmost half of the patients underwent rapid clinical progression within 2 years after HIV infection. A treat-all policy is necessary and should be strengthened globally. Rapid progression was correlated with herpes simplex-2 virus coinfection, depression, low CD4+ T cell counts, and high set point viral load in acute infection stage. Rapid progression can be identified via simple indicators such as body mass index and routine blood test parameters in low and middle-income countries.

Quantitative Peptidomics of Mouse Brain After Infection With Cyst-Forming Toxoplasma gondii.

Toxoplasma gondii is an obligate intracellular parasite capable of establishing persistent infection within the host brain and inducing severe neuropathology. Peptides are important native molecules responsible for a wide range of biological functions within the central nervous system. However, peptidome profiling in host brain during T. gondii infection has never been investigated. Using a label-free peptidomics approach (LC–MS/MS), we identified a total of 2,735 endogenous peptides from acutely infected, chronically infected and control brain samples following T. gondii infection. Quantitative analysis revealed 478 and 344 significantly differentially expressed peptides (DEPs) in the acute and chronic infection stages, respectively. Functional analysis of DEPs by Gene Ontology suggested these DEPs mainly originated from cell part and took part in cellular process. We also identified three novel neuropeptides derived from the precursor protein cholecystokinin. These results demonstrated the usefulness of quantitative peptidomics in determining bioactive peptides and elucidating their functions in the regulation of behavior modification during T. gondii infection.

COVID-19 dermatological manifestations

COVID-19 is an ongoing multisystemic viral infection, which affects both adults and children. The virus has a complicated and not fully understood pathophysiological mechanism of damaging different organs and systems, including the skin. Cutaneous manifestations classification is complicated by the great variety of lesions and histological appearances, neither specific. Herein, a thorough overview of the clinical and pathological peculiarities of skin changes observed in the acute and re-convalescent stages of COVID-19 infection, is highlighted. The pathophysiological mechanisms, suggested to trigger and sustain the dermatological dysfunction, are also considered in the vicinity of authors’ personal experience.

Limited Impact of the Inhibitory Receptor TIGIT on NK and T Cell Responses during Toxoplasma gondii Infection.

Resistance to the parasite Toxoplasma gondii is mediated by NK and T cell production of IFN-γ, but the failure to contract this response can lead to severe T cell-dependent immunopathology. Although the cytokines IL-10 and IL-27 prevent immune hyperactivity during toxoplasmosis, inhibitory receptors, expressed by NK and T cells, are also implicated in this process. The inhibitory receptor TIGIT is expressed on NK and T cells and competes with the costimulatory receptor CD226 for binding of the ligand CD155. During toxoplasmosis, the activation of NK and T cells is associated with increased expression of CD226 and TIGIT, whereas DCs express increased levels of CD155. To determine if the loss of TIGIT impacts NK and T cell activities, wild-type and TIGIT knockout mice were infected with T. gondii During the acute stage of infection, wild-type and TIGIT knockout mice had comparable parasite burdens and similar NK and T cell responses. Likewise, during the chronic phase of this infection, the loss of TIGIT did not affect the magnitude or phenotype of the T cell response nor the ability to control pathogen load. These data suggest that during toxoplasmosis, despite upregulation of relevant ligands, TIGIT signaling does not limit NK and T cell activities. Thus, TIGIT-independent mechanisms dominate the restraint of the immune response during toxoplasmosis.

Endoscopic coblation treatment for congenital pyriform sinus fistula in children.

Congenital pyriform sinus fistula (CPSF) is a very rare branchial apparatus malformation. Traditional open surgery for fistulectomy might fail to excise the lesion completely, leading to continual recurrence. Herein, we report our experience of endoscopic coblation technique for treatment of CPSF in children.To observe the clinical efficacy of endoscopic coblation treatment of CPSF in children, especially for those in acute infection stage.Retrospective case series with 54 patients (including 20 cases in acute infection stage and 34 cases in non infection stage) who were diagnosed with CPSF between October 2017 to November 2019, all patients were treated with endoscopic coblation to close the piriform fossa fistula, neck abscess incision and drainage performed simultaneously for acute infection stage cases. Data collected including age of diagnosis, presenting symptoms, diagnostic methods, prior and subsequent treatments, length of hospitalization, and recurrence were analyzed.Of the 20 cases in acute infection stage, there were 3 children with transient vocal cord paresis all of which resolved with 1 month. Four children of the 34 cases in non infection stage appeared reddish swelling of the neck on the 4th, 5th, 6th, and 7th days after coblation and then underwent abscess incision and drainage. All cases experienced no recurrence, vocal cord paralysis, pharyngeal fistula and massive hemorrhage after their first endoscopic coblation of the sinus tract in the follow up of 3 to 28 months.Endoscopic coblation is an effective and safe approach for children with CPSF, neck abscess incision and drainage could be performed simultaneously in acute infection stage. We advocate using this minimally invasive technique as first line of treatment for CPSF.

The effect of passive immunization on the acute phase of infection in a murine model of EHV‐1.

Equine herpes virus 1 causes respiratory infection in equine world-wide. Virus replicates in the respiratory tissues in ciliated and non-ciliated epithelial cells lining the nasal turbinate bones, trachea, bronchi, bronchioles, and type I and type II pneumocytes, and becomes viraemic causing myeloencephalopathy (paresis) and retinopathy. The virus later becomes latent. While active the virus crosses the placenta and leads to abortion of dead or dying foetuses and neonatal death. Infected horses show transient immunity after natural or experimental infection and immune responses to EHV-1 begin to decline after a few months of infection. Due to the transient nature of the immune response, horses are prone to subsequent reinfection and as a result development of an effective vaccine continues to be a challenge till to date. In order to discover the role of neutralizing antibodies in the pathogenesis of EHV-1 infection, we studied the role of neutralizing antibodies in a murine model of infection during the acute stage of infection by passively immunizing mice by the subcutaneous route with a pre-immune or hyperimmune polyclonal rabbit neutralizing serum 24 hours before virus infection. Mice were challenged intranasally with live EHV-1 virus and virus replication in the respiratory tissues was studied on day 3 and 5 post infection (p.i., acute stage of infection). The effect of passive immunization was also studied on viraemia by infectious centers assays from buffy coat cells. Slight reduction in virus titres in the respiratory tissues and level of viraemia was noted on day 3 p.i, but this difference was not significant. However significant reduction was seen in virus titres both in respiratory tissues and on the state of viraemia on day 5 in passively immunized animals compared with the controls given pre-immune sera from the same rabbit. The sera of passively transferred mice were also tested for presence of rabbit neutralizing antibodies on day 3 and 5 (days 4 and 6) of antibody transfer, suggesting that for complete protection neutralizing IgA may be required at the mucosal surface to stop or otherwise inhibit the viral attachment and thereby explain the differences in viral titres. These results of antibody transfer at an acute stage of infection will be discussed in this communication.

Salivary microbial diversity at different stages of human immunodeficiency virus infection

Human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) disrupts the host microbial balance. During disease progression, the oral microbial environment is altered in untreated people living with HIV/AIDS (PLWHA); however, no studies have reported changes in salivary microbial diversity during different stages of HIV infection. Therefore, in this study, we aimed to assess the relationships between immune dysfunction and changes in saliva microbiota. To this end, we collected saliva samples from 11 HIV-negative individuals and 44 PLWHA during different stages based on the Centers for Disease Control and Prevention criteria (stage 0, early stage during the first 6 months after infection; stages 1, 2, and 3 associated with CD4+ T-lymphocyte counts of ≥500, 200–499, and ≤200 or opportunistic infection, respectively). We analyzed salivary microbial community diversity using polymerase chain reaction amplification and Illumina MiSeq sequencing. We found that HIV-positive individuals had significantly greater alpha-diversity in the microbial community composition compared with HIV-negative controls (P < 0.05) except for AIDS (stage 3); however, the predominant salivary microbiota in the five groups remained similar. Porphyromonas in the four positive groups was the only genus that was significantly less abundant in the HIV-positive groups than in the control group (P < 0.05). There were some consistencies between the general abundance of salivary microbiota and AIDS disease progression. Lots of bacterial abundances in the saliva increased dramatically during the acute HIV infection (stage 0), and some of the negligible and abnormally proliferating bacteria in the asymptomatic stage showed a downward trend. Additionally, in the AIDS stage, partial inhibition was observed. Notably, Porphyromonas was closely related to the immune activation of HIV, showing a decline in abundance once infected with HIV. Solobacterium, which induces inflammation, was negatively correlated with CD4 counts. Overall, our findings provided important insights into changes in salivary microbial diversity in PLWHA.

Establishment of infection mode and Penaeus monodon hemocytes transcriptomics analysis under decapod iridescent virus 1 (DIV1) challenge

With the increasing density of shrimp breeding, environmental deterioration and stress associated with intensification have caused diseases occurred frequently. Due to the high fatality rate of decapod iridescent virus 1 (DIV1), a new type of virus discovered in shrimp in recent years, it has caused serious damage to the shrimp farming industry. Penaeus monodon is one of the commonly cultivated species of prawns in the world. In the current study, LD50 was calculated to evaluate the virulence of DIV1 and the DIV1 copies in five tissues were quantitatively detected, which proved that P. monodon could be a host of DIV1. On these basis, a stable and effective DIV1 infection (including latent infection and acute infection) model was established for the first time. In addition, RNA-Seq platform and bioinformatics analysis were used to investigate the hemocyte immune response to DIV1 infection in P. monodon. A total of 31,657 unigenes were find significant assembled when compared to known sequences in major databases, and a total of 29,820 SSRs were obtained in the hemocytes transcriptome. A total of 6236 differentially expressed genes (DEGs) were identified, including 3140 up-regulated genes and 3096 down-regulated genes. Through the KEGG pathway enrichment analysis of DEGs, six immune-related pathways were enriched significantly, including Toll and Imd signaling pathway, PI3K-Akt signaling pathway, NF-kappa B signaling pathway, NOD-like receptor signaling pathway, Lysosome and MAPK signaling pathway. Moreover, many DEGs associated with Cholesterol metabolism, Pyruvate metabolism, Arginine and proline metabolism, Nicotinate and nicotinamide metabolism, Pyrimidine metabolism, Tyrosine metabolism and Alanine, aspartate and glutamate metabolism were also significantly modified. Moreover, Glycolysis / Gluconeogenesis and Pentose phosphate pathway, as the markers of Warburg effect, were significantly up-regulated after DIV1 infection. This study provides an ideal infection model for studying the molecular mechanism of P. monodon from the latent infection stage to the acute infection stage, initially reveals the molecular mechanism of DIV1 infection in P. monodon and provides valuable genetic resources and research methods for following molecular marker development and screening the families of P. monodon resistant to DIV1. The ultimate goal is to develop methods to avoid disease outbreaks in farmed shrimp.

A Family of Toxoplasma gondii Genes Related to GRA12 Regulate Cyst Burdens and Cyst Reactivation.

ABSTRACTToxoplasma gondii causes a chronic infection that renders the immunocompromised human host susceptible to toxoplasmic encephalitis triggered by cyst reactivation in the central nervous system. The dense granule protein GRA12 is a major parasite virulence factor required for parasite survival during acute infection. Here, we characterized the role of four GRA12-related genes in acute and chronic stages of infection. While GRA12A, GRA12B, and GRA12D were highly expressed in asexual stage tachyzoites and bradyzoites, expression of GRA12C appeared to be restricted to the sexual stages. In contrast to deletion of GRA12 (Δgra12), no major defects in acute virulence were observed in Δgra12A, Δgra12B, or Δgra12D parasites, though Δgra12B parasites exhibited an increased tachyzoite replication rate. Bradyzoites secreted GRA12A, GRA12B, and GRA12D and incorporated these molecules into the developing cyst wall, as well as the cyst matrix in distinct patterns. Similar to GRA12, GRA12A, GRA12B, and GRA12D colocalized with the dense granules in extracellular tachyzoites, with GRA2 and the intravacuolar network in the tachyzoite stage parasitophorous vacuole and with GRA2 in the cyst matrix and cyst wall. Chronic stage cyst burdens were decreased in mice infected with Δgra12A parasites and were increased in mice infected with Δgra12B parasites. However, Δgra12B cysts were not efficiently maintained in vivo. Δgra12A, Δgra12B, and Δgra12D in vitro cysts displayed a reduced reactivation efficiency, and reactivation of Δgra12A cysts was delayed. Collectively, our results suggest that a family of genes related to GRA12 play significant roles in the formation, maintenance, and reactivation of chronic stage cysts.IMPORTANCE If host immunity weakens, Toxoplasma gondii cysts recrudesce in the central nervous system and cause a severe toxoplasmic encephalitis. Current therapies target acute stage infection but do not eliminate chronic cysts. Parasite molecules that mediate the development and persistence of chronic infection are poorly characterized. Dense granule (GRA) proteins such as GRA12 are key virulence factors during acute infection. Here, we investigated four GRA12-related genes. GRA12-related genes were not major virulence factors during acute infection. Instead, GRA12-related proteins localized at the cyst wall and cyst matrix and played significant roles in cyst development, persistence, and reactivation during chronic infection. Similar to GRA12, the GRA12-related proteins selectively associated with the intravacuolar network of membranes inside the vacuole. Collectively, our results support the hypothesis that GRA12 proteins associated with the intravacuolar membrane system support parasite virulence during acute infection and cyst development, persistence, and reactivation during chronic infection.

A Highly Sensitive and Specific Probe-Based Real-Time PCR for the Detection of Avibacterium paragallinarum in Clinical Samples From Poultry.

Avibacterium paragallinarum (historically called Hemophilus paragallinarum) causes infectious coryza (IC), which is an acute respiratory disease of chickens. Recently, outbreaks of IC have been reported in Pennsylvania (PA) in broilers, layer pullets, and laying hens, causing significant respiratory disease and production losses. A tentative diagnosis of IC can be made based on history, clinical signs, and characteristic gross lesions. However, isolation and identification of the organism are required for a definitive diagnosis. Major challenges with the bacteriological diagnosis of A. paragallinarum include that the organism is difficult to isolate, slow-growing, and can only be successfully isolated during the acute stage of infection and secondary bacterial infections are also common. As there were very limited whole genomes of A. paragallinarum in the public databases, we carried out whole-genome sequencing (WGS) of PA isolates and based on the WGS data analysis; we designed a novel probe-based PCR assay targeting a highly conserved sequence in the recN, the DNA repair protein gene of A. paragallinarum. The assay includes an internal control, with a limit of detection (LOD) of 3.93 genomic copies. The PCR efficiency ranged between 90 and 97%, and diagnostic sensitivity of 98.5% compared with conventional gel-based PCR. The test was highly specific, and no cross-reactivity was observed with other species of Avibacterium and a range of other common poultry respiratory viral and bacterial pathogens. Real-time PCR testing on 419 clinical samples from suspected flocks yielded 94 positives and 365 negatives in agreement with diagnostic bacterial culture-based detection. We also compared the recN PCR assay with a previous HPG-2 based real-time PCR assay which showed a PCR efficiency of 79%.

Dual VP28 and VP37 dsRNA encapsulation in IHHNV virus-like particles enhances shrimp protection against white spot syndrome virus

Accumulative evidence of using double stranded (ds) RNA encapsulated into virus like particle (VLP) nanocarrier has open feasibility to fight against shrimp viral infection in aquaculture field. In this study, we co-encapsulated VP37 and VP28 dsRNA into hypodermal and hematopoietic necrosis virus (IHHNV) like particle and investigated its protection against white spot syndrome virus (WSSV). Five micrograms of each dsRNA were used as starting materials to load into VLP, while the loading efficiency was slightly different, i.e, VP37 dsRNA had somewhat a better load into VLP's cavity. It was apparent that co-encapsulation of dual dsRNA showed a superior WSSV silencing ability than the single dsRNA counterpart as evidence by the lower WSSV gene expression and its copy number in the gill tissues. Besides, we also demonstrated that co-encapsulated dual dsRNA into IHHNV-VLP stimulated the increased number of hemocytes and the corresponding PO activity as well as up-regulated proPO gene expression in hemocytes to resist viral invasion after an acute stage of WSSV infection. This synergistic action of dual dsRNA encapsulated into IHHNV-VLPs could thus act to delay time of shrimp death and reduced shrimp cumulative mortality greater than the single, naked dsRNA treatment and positive control groups. The obtaining results would encourage the feasibility to use it as a new weapon to fight WSSV infection in shrimp aquaculture.

Long Term Health Sequelae of COVID-19: A Review

The outbreak of Coronavirus disease 19 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was declared a pandemic by World Health Organization (WHO) on 11th March, 2020. COVID-19 infection predominantly manifests as pulmonary symptoms that may progress to acute respiratory distress syndrome. The data on extra-pulmonary manifestations of acute COVID-19 are available. Most patients who have COVID-19 recover well within months. Currently, more than 50 million people have recovered globally. Many reports of patients with persistent severe symptoms and significant end-organ damage after SARS-CoV-2 infection have also been observed. As COVID-19 is a relatively new disease, future sequelae aren’t well established. Major adverse outcomes were found to affect different body systems: respiratory system (lung fibrosis and pulmonary thromboembolism), cardiovascular system (cardiomyopathy), and neurological system (sensory dysfunction and stroke). Mental health of COVID-19 patients were also found to be adversely affected. This review describes the effects of SARS-CoV-2 taking into account the previous experiences with SARS-CoV-2 and the Middle East Respiratory Syndrome (MERS) coronavirus that caused SARS in 2003 and MERS in 2012 respectively. This review aims to update on the long-term sequelae of SARS-CoV-2 infection and highlight the necessity for patient monitoring following the acute stage of infection with SARS-CoV-2 to provide ground for the prevention, diagnosis, and management of these potential long-term sequelae and to complete the natural history of COVID-19.

Airway gene-expression classifiers for respiratory syncytial virus (RSV) disease severity in infants

BackgroundA substantial number of infants infected with RSV develop severe symptoms requiring hospitalization. We currently lack accurate biomarkers that are associated with severe illness.MethodWe defined airway gene expression profiles based on RNA sequencing from nasal brush samples from 106 full-tem previously healthy RSV infected subjects during acute infection (day 1–10 of illness) and convalescence stage (day 28 of illness). All subjects were assigned a clinical illness severity score (GRSS). Using AIC-based model selection, we built a sparse linear correlate of GRSS based on 41 genes (NGSS1). We also built an alternate model based upon 13 genes associated with severe infection acutely but displaying stable expression over time (NGSS2).ResultsNGSS1 is strongly correlated with the disease severity, demonstrating a naïve correlation (ρ) of ρ = 0.935 and cross-validated correlation of 0.813. As a binary classifier (mild versus severe), NGSS1 correctly classifies disease severity in 89.6% of the subjects following cross-validation. NGSS2 has slightly less, but comparable, accuracy with a cross-validated correlation of 0.741 and classification accuracy of 84.0%.ConclusionAirway gene expression patterns, obtained following a minimally-invasive procedure, have potential utility for development of clinically useful biomarkers that correlate with disease severity in primary RSV infection.

The evaluation of myocardial performance index in patients with COVID-19: An echocardiographic follow-up study

Funding AcknowledgementsType of funding sources: None.IntroductionThe epidemic of pneumonia caused by a new coronavirus rapidly spread all over the world. World Health Organization called the condition as coronavirus disease 2019 (COVID-19). COVID-19 has become a life-threatening public health emergency internationally. COVID-19 mostly presents by respiratory tract symptoms including fever, dry cough, and dyspnea. The disease progression causes pneumonia and acute respiratory distress syndrome. Pathophisyology of cardiovascular effects of COVID-19 have not been well known yet. Myocardial dysfunction may occur in cytokine-originated immune reactions. Myocardial performance index (MPI) is a feasible parameter that reflects systolic and diastolic cardiac functions.PurposeWe aimed to evaluate the MPI in patients with COVID-19.MethodsThe study consisted of 40 patients diagnosed with COVID-19 who had mild pneumonia and had not needed intensive care treatment. Transthoracic echocardiographic examination was performed in all patients at the acute stage of infection and after clinical recovery. The average time interval between the baseline and recovery echocardiography exam was about 28 ± 3,4 days. Blood samples were studied on day 0 and on days 7, 14, 21, and 28. Immunofluorescence assay was used for COVID-19 antibody titers. Respiratory secretions were sent for RT-PCR tests.ResultsThe mean age was 54 ± 11 years ( male 26 (65% ) ). Statistically significant higher MPI (0.56 ± 0.09 versus 0.44 ± 0.07, p < 0.001), longer isovolumic relaxation time (112.3 ± 13.4 versus 91.8 ± 12.1ms, p < 0.001), longer deceleration time (182.1 ± 30.6 versus 161.5 ± 43.5ms, p = 0.003), shorter ejection time (279.6 ± 20.3 versus 298.8 ± 36.8ms, p < 0.001) and higher E/A ratio (1.53 ± 0.7 versus 1.22 ± 0.4, p < 0.001), were observed during acute period of infection compared to ones after clinical recovery. Compared with basal values, no significant change in left ventricular systolic ejection fraction was observed after clinical recovery (60.3± 3.2% versus 61.7 ± 2.4%, p > 0.05). Isovolumic contraction time was similar at acute infection and after clinical recovery ( 44.3 ± 7.8 versus 40.6 ± 9.7ms, p > 0.05)ConclusionIn conclusion, our study suggests global reversible LV dysfunction in COVID-19 patients with preserved LV systolic function based on tissue Doppler derived MPI. This could be due to isolated subclinical diastolic dysfunction. To our knowledge, this study is the first echocardiographic follow-up study that evaluated the systolic and diastolic function of the left ventricle in COVID -19 patients. The underlying mechanism and its clinical significance can be established by further studies.

Dynamics in myocardial deformation as an indirect marker of myocardial involvement in acute myocarditis due to HIV infection: a case report.

BackgroundThe diagnosis of acute myocarditis (AM) is often challenging and mainly performed by cardiac magnetic resonance (CMR).Case summaryThe present case describes echocardiographic findings of a 38-year-old male patient with exertional dyspnoea probably due to myocardial involvement of previously undiagnosed acute human immunodeficiency virus (HIV) infection. Myocardial deformation imaging might be helpful to detect early stages of myocardial dysfunction in patients with AM and/or systemic infectious diseases by documentation of patchy abnormalities of longitudinal, circumferential and rotational left ventricular (LV) deformation.DiscussionCMR still represents the gold standard to diagnose AM, which has been confirmed by myocardial oedema and hyperaemia in the present case. However, speckle tracking echocardiography seems to be useful to detect myocardial involvement in HIV infection by dynamic alterations of different components of LV deformation. This was documented by comparing echocardiographic findings at the acute stage of HIV infection to findings at follow-ups during antiviral treatment. The diagnostic option to detect myocardial involvement by deformation imaging in a patient with HIV infection is described for the first time.