Shedding Period Research Articles

Evaluation of the Effects of Papain on Schistosoma mansoni: Miracidial Infection Capacity, Infection Prevalence, Cercarial Shedding and Molecular Changes in Biomphalaria alexandrina.

The aim of the present study is to assess the molluscicidal, larvicidal and genotoxicological activities of papain and how it can affect the host-parasite interactions. Toxicity of papain on snails by making series of concentrations to calculate LC50, and then study its larvicide effect on the free larval stages of S. mansoni and infection rate of snails. Papain has a molluscicidal activity on adult snails of Biomphalaria alexandrina with a lethal concentration LC50 equals to 43.1mg/L. In addition, it has activity on miracidia with half Lethal time (LT50) of 16.11min., and on cercariae with 12.1min. compared to control ones. The sub lethal concentration LC10 and LC25 (6.9 or 24.1mg/L, respectively) decreased the survival rate of snails at the first cercarial shedding, the rate of infection, the average total number of cercariae per snail, the shedding period and the life span of snails, while the prepatent period was significantly increased than the control ones. The morphological alterations in cercariae after exposure to papain were occurred where the cercariae lacked motility and some had a dark tail with complete detachment of head and tail. Compared to the control group, the levels of cytochrome oxidase subunit I (COI) and (ND1) genes significantly decreased in snails after exposure to papain. Papain could be used as a potential molluscicide for elimination of schistosomiasis and decrease its transmission and deterioration of host-parasite interaction.

SARS-CoV-2 delta variant in African lions (Panthera leo) and humans at Utah's Hogle Zoo, USA, 2021-22.

We conducted a One Health investigation to assess the source and transmission dynamics of SARS-CoV-2 infection in African lions (Panthera leo) at Utah's Hogle Zoo in Salt Lake City from October 2021 to February 2022. Following observation of respiratory illness in the lions, zoo staff collected pooled faecal samples and individual nasal swabs from four lions. All specimens tested positive for SARS-CoV-2 by reverse transcription-polymerase chain reaction (RT-PCR). The resulting investigation included: lion observation; RT-PCR testing of lion faeces every 1-7 days; RT-PCR testing of lion respiratory specimens every 2-3 weeks; staff interviews and RT-PCR testing; whole-genome sequencing of viruses from lions and staff; and comparison with existing SARS-CoV-2 human community surveillance sequences. In addition to all five lions, three staff displayed respiratory symptoms. All lions recovered and no hospitalizations or deaths were reported among staff. Three staff reported close contact with the lions in the 10 days before lion illness onset, one of whom developed symptoms and tested positive for SARS-CoV-2 on days 3 and 4, respectively, after lion illness onset. The other two did not report symptoms or test positive. Two staff who did not have close contact with the lions were symptomatic and tested positive on days 5 and 8, respectively, after lion illness onset. We detected SARS-CoV-2 RNA in lion faeces for 33 days and in lion respiratory specimens for 14 weeks after illness onset. The viruses from lions were genetically highly related to those from staff and two contemporaneous surveillance specimens from Salt Lake County; all were delta variants (AY.44). We did not determine the sources of these infections, although human-to-lion transmission likely occurred. The observed period of respiratory shedding was longer than in previously documented SARS-CoV-2 infections in large felids, indicating the need to further assess duration and potential implications of shedding.

Matched Three-Dimensional Organoids and Two-Dimensional Cell Lines of Metastatic Melanoma to the Brain Mirrors Response to Targeted Molecular Therapy

INTRODUCTION: Metastatic melanoma to the brain (MMB) represents a significant treatment challenge. Limitations in preclinical models, namely the lack of heterogeneity in cell lines and low throughput of xenograft models, have thwarted novel therapeutic development. Surgically eXplanted Organoids (SXOs) are ex vivo, three-dimensional models that recapitulate genotypic and phenotypic features of parent tumors with minimal extracranial processing. We aim to develop the first known matched patient-derived SXO and cell line of BRAF-mutant MMB to investigate responses to targeted therapy. METHODS: MMB SXOs were created by a novel protocol incorporating techniques for creating glioma and cutaneous melanoma organoids. A BRAFV600K-mutant MMB sample was collected and processed within 30 minutes of resection. SXOs were created using a 1.0 mm biopsy punch. Organoids were cultured in low-adherence plates in an optimized culture medium under continuous orbital rotation without an artificial extracellular scaffold. Organoid media was changed every 48 hours. Concurrently, matched patient-derived cell lines were created and passaged weekly. Drug screens were conducted with the CellTiter-Glo Luminescence Viability Assay (cell line) and ReadyProbe Cell Viability Imaging Kit (SXOs). RESULTS: After an initial shedding period, organoid growth was observed within 3-4 weeks. MMB SXOs retained histological phenotypes of the parent tissue, including pleomorphic epithelioid cells with abundant cytoplasm, large nuclei, focal melanin accumulation, strong Sox10 positivity, and HMB45 positivity. After sufficient growth, organoids could be manually parcellated to increase the number of replicates. Matched SXOs and cell lines demonstrated sensitivity to BRAF-V600 and MEK inhibitors. CONCLUSIONS: Here, we outline the creation of the first known scaffold-free organoid model of MMB. Further study using SXOs will improve the translational relevance of preclinical studies and enable the study of the melanoma tumor microenvironment.

Strongyle egg shedding and egg reappearance periods in horses with pituitary pars intermedia dysfunction

Pituitary pars intermedia dysfunction (PPID) is the most common endocrine disorder of older horses. Immune dysfunction in horses with PPID could increase susceptibility to infectious diseases, including strongyle infections; however, few data are available. The aim of this study was to determine if horses with PPID had increased strongyle faecal egg counts (FEC) compared with control horses, over a fourteen-week period in Victoria, Australia. Clinical signs and plasma adrenocorticotropic hormone (ACTH) concentrations were used to categorise horses into PPID (n=14) or control (n=31) groups. Faecal samples were collected for FEC determination prior to anthelmintic treatment, and fortnightly post-treatment for each horse. Generalised linear mixed modelling, using a gamma distribution, was used to compare differences between groups in the repeated measures study. The confounding variable of age was controlled for as a fixed effect. Following anthelmintic treatment, mean FEC was greater for the PPID group compared to the control group on day 56 (405 ± 756 eggs per gram [EPG] vs 40 ± 85 EPG, p=0.05) and day 70 (753 ±1598 EPG vs 82 ±141 EPG, p=0.04). There were no differences in mean FEC between groups on days 84 and 98. Cumulative FEC (day 14 to day 98) was significantly greater for the PPID horses than control horses (2118 ± 4016 EPG vs 798 ± 768 EPG, p<0.0001). Group egg reappearance period was shorter for PPID horses (day 56 post-anthelmintic treatment) compared to control horses (day 70) and 30% of the PPID horses reached a FEC threshold of >200 EPG on day 42, compared to 0% of control horses (p=0.02). These results suggest that the rate of a re-established patent infection between groups could be different due to a comprised immune response in PPID horses or differences in the host-parasite relationship regarding encysted stage larvae. However, despite differences between groups, some horses with PPID consistently had no detectable or low FEC (<200 EPG) during the study period. These findings highlight the importance of individual FEC monitoring to determine if anthelmintic treatment is required, in line with sustainable parasite management practices.

Effect of enrofloxacin on clinical parameters and mucociliary system of broilers challenged with H9N2 avian influenza/infectious bronchitis viruses.

Effect of antibacterials on mucociliary system and clinical outcome of chickens with mixed viral respiratory conditions is not properly addressed. We evaluated enrofloxacin effects on clinical parameters and mucociliary system of broilers challenged with H9N2/IB viruses. Broilers (105), at the age of 25 days, were randomly allocated into three groups: Group 1 (negative control), no treatment; Group 2 (positive control [PC]) challenged by intranasal and intraocular route. Group 3 (antibiotic [AB]-treated) challenged and also received enrofloxacin started after manifestation of clinical signs (day 2 post-challenge [pc]) and continued for 5 days. Administration of AB was not associated with appreciable changes in body weight, feed conversion ratio (FCR) or the severity of clinical signs although it slightly reduced mortality rate as compared to PC group (p>0.05). Virus shedding period and number of virus positive tracheal and caecal tonsil samples were also statistically similar between PC and AB groups. In necropsy, the most profound effect of AB was decreased pleuropneumonia severity score on day 12 pc. Histopathological lesion scores were statistically the same between PC and AB groups. However, the administration of AB increased the number of tracheal goblet cells, with no effect on ciliostasis. We found a weak positive effect of enrofloxacin administration in H9N2/IB-infected chickens. Considering the risks of AB treatment in broiler chickens, the results of this small-scale study do not encourage the benefit of enrofloxacin use in these viral diseases.

Severe Acute Respiratory Syndrome Coronavirus 2 Omicron Variant Kinetics in Natural Infection: A Case Study

Background Omicron has become the mainstream epidemic variant of severe acute respiratory syndrome coronavirus 2 worldwide. One reason for the high infectivity of this variant is its ability to multiply rapidly in the human body. It has been speculated that, in general, the short period required for virus multiplication affects the incubation period and timing of viral shedding that begins during the incubation period. However, it is unclear whether these effects can be related to the Omicron variant. Similar to a recent human challenge study, in this study, patients with known timing of Omicron infection were followed up in a hospital before the onset of the disease. &#x0D; Methods In two patients, the viral shedding was investigated and analysed along with symptoms before and after the disease onset.&#x0D; Results The incubation period for Omicron was 30-36 h; this was shorter than the average incubation period of the alpha variant in the human challenge study and that reported in a systematic review and meta-analysis (3.5 days). Viral shedding at the nasal site began 19-22 h after infection, approximately 10 h before symptom onset.&#x0D; Conclusion The results of this study demonstrated that in some instances with Omicron (BA.5), the time to viral shedding and the time to disease onset were considerably shorter after infection than those previously reported for Omicron and Alpha variants. We showed the importance of early detection of the viral antigen after viral exposure and early isolation initiation to prevent infection spread.

Transmission characteristics and inactivated vaccine effectiveness against transmission of the SARS-CoV-2 Omicron BA.2 variant in Shenzhen, China.

We conducted a retrospective cohort study to evaluate the transmission risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron BA.2 variant and the effectiveness of inactivated COVID-19 vaccine boosters in Shenzhen during a BA.2 outbreak period from 1 February to 21 April 2022. A total of 1,248 individuals were infected with the BA.2 variant, and 7,855 close contacts were carefully investigated. The risk factors for the high secondary attack rate of SARS-CoV-2 infection were household contacts [adjusted odds ratio (aOR): 1.748; 95% confidence interval (CI): 1.448, 2.110], younger individuals aged 0-17 years (aOR: 2.730; 95% CI: 2.118, 3.518), older persons aged ≥60 years (aOR: 1.342; 95% CI: 1.135, 1.588), women (aOR: 1.442; 95% CI: 1.210, 1.718), and the subjects exposed to the post-onset index cases (aOR: 8.546; 95% CI: 6.610, 11.050), respectively. Compared with the unvaccinated and partially vaccinated individuals, a relatively low risk of secondary attack was found for the individuals who received booster vaccination (aOR: 0.871; 95% CI: 0.761, 0.997). Moreover, a high transmission risk was found for the index cases aged ≥60 years (aOR: 1.359; 95% CI: 1.132, 1.632), whereas a relatively low transmission risk was observed for the index cases who received full vaccination (aOR: 0.642; 95% CI: 0.490, 0.841) and booster vaccination (aOR: 0.676; 95% CI: 0.594, 0.770). Compared with full vaccination, booster vaccination of inactivated COVID-19 vaccine showed an effectiveness of 24.0% (95% CI: 7.0%, 37.9%) against BA.2 transmission for the adults ≥18 years and 93.7% (95% CI: 72.4%, 98.6%) for the adults ≥60 years, whereas the effectiveness was 51.0% (95% CI: 21.9%, 69.3%) for the individuals of 14 days to 179 days after booster vaccination and 51.2% (95% CI: 37.5%, 61.9%) for the non-household contacts. The estimated mean values of the generation interval, serial interval, incubation period, latent period, and viral shedding period were 2.7 days, 3.2 days, 2.4 days, 2.1 days, and 17.9 days, respectively. In summary, our results confirmed that the main transmission route of Omicron BA.2 subvariant was household contact, and booster vaccination of the inactivated vaccines was relatively effective against BA.2 subvariant transmission in older people.

Vaccination Shapes Within-Host SARS-CoV-2 Diversity of Omicron BA.2.2 Breakthrough Infection.

Low-frequency intrahost single-nucleotide variants of SARS-CoV-2 have been recognized as predictive indicators of selection. However, the impact of vaccination on the intrahost evolution of SARS-CoV-2 remains uncertain at present. We investigated the genetic variation of SARS-CoV-2 in individuals who were unvaccinated, partially vaccinated, or fully vaccinated during Shanghai's Omicron BA.2.2 wave. We substantiated the connection between particular amino acid substitutions and immune-mediated selection through a pseudovirus neutralization assay or by cross-verification with the human leukocyte antigen-associated T-cell epitopes. In contrast to those with immunologic naivety or partial vaccination, participants who were fully vaccinated had intrahost variant spectra characterized by reduced diversity. Nevertheless, the distribution of mutations in the fully vaccinated group was enriched in the spike protein. The distribution of intrahost single-nucleotide variants in individuals who were immunocompetent did not demonstrate notable signs of positive selection, in contrast to the observed adaptation in 2 participants who were immunocompromised who had an extended period of viral shedding. In SARS-CoV-2 infections, vaccine-induced immunity was associated with decreased diversity of within-host variant spectra, with milder inflammatory pathophysiology. The enrichment of mutations in the spike protein gene indicates selection pressure exerted by vaccination on the evolution of SARS-CoV-2.

Flow topology in the gap and wake of convex curved tandem cylinders

Flow around curved tandem cylinders in the convex configuration has been studied by means of direct numerical simulations, for a Reynolds number of 500 and a nominal gap ratio of 3.0. Spanwise variation of flow regimes, as well as curvature-induced axial velocity, leads to an exceedingly complex vortex dynamics in the wake. Both parallel and oblique vortex shedding are observed. Oblique shedding is connected to repeated occurrences of dislocations. The dislocations are caused by two main mechanisms: frequency differences in the upper part of the curved geometry and shedding of gap vortices into the lower near wake. Both types of dislocations are closely associated with a mode switch in the gap. In parts of the gap, there is low-frequency quasi-periodic asymmetry of the gap vortices, where the flow is biased to one side of the gap for intervals of several wake vortex shedding periods. The switch from side to side is associated with a surge of the vertical velocity, and the frequency of the switch is similar to that of long-term variation of the recirculation length in the lower gap.

Pathogenicity in Chickens and Turkeys of a 2021 United States H5N1 Highly Pathogenic Avian Influenza Clade 2.3.4.4b Wild Bird Virus Compared to Two Previous H5N8 Clade 2.3.4.4 Viruses.

Highly pathogenic avian influenza viruses (HPAIVs) of subtype H5 of the Gs/GD/96 lineage remain a major threat to poultry due to endemicity in wild birds. H5N1 HPAIVs from this lineage were detected in 2021 in the United States (U.S.) and since then have infected many wild and domestic birds. We evaluated the pathobiology of an early U.S. H5N1 HPAIV (clade 2.3.4.4b, 2021) and two H5N8 HPAIVs from previous outbreaks in the U.S. (clade 2.3.4.4c, 2014) and Europe (clade 2.3.4.4b, 2016) in chickens and turkeys. Differences in clinical signs, mean death times (MDTs), and virus transmissibility were found between chickens and turkeys. The mean bird infective dose (BID50) of the 2021 H5N1 virus was approximately 2.6 log10 50% embryo infective dose (EID50) in chickens and 2.2 log10 EID50 in turkeys, and the virus transmitted to contact-exposed turkeys but not chickens. The BID50 for the 2016 H5N8 virus was also slightly different in chickens and turkeys (4.2 and 4.7 log10 EID50, respectively); however, the BID50 for the 2014 H5N8 virus was higher for chickens than turkeys (3.9 and ~0.9 log10 EID50, respectively). With all viruses, turkeys took longer to die (MDTs of 2.6-8.2 days for turkeys and 1-4 days for chickens), which increased the virus shedding period and facilitated transmission to contacts.

Viral maintenance and excretion dynamics of coronaviruses within an Egyptian rousette fruit bat maternal colony: considerations for spillover

Novel coronavirus species of public health and veterinary importance have emerged in the first two decades of the twenty-first century, with bats identified as natural hosts for progenitors of many coronaviruses. Targeted wildlife surveillance is needed to identify the factors involved in viral perpetuation within natural host populations, and drivers of interspecies transmission. We monitored a natural colony of Egyptian rousette bats at monthly intervals across two years to identify circulating coronaviruses, and to investigate shedding dynamics and viral maintenance within the colony. Three distinct lineages were detected, with different seasonal temporal excretion dynamics. For two lineages, the highest periods of coronavirus shedding were at the start of the year, when large numbers of bats were found in the colony. Highest peaks for a third lineage were observed towards the middle of the year. Among individual bat-level factors (age, sex, reproductive status, and forearm mass index), only reproductive status showed significant effects on excretion probability, with reproductive adults having lower rates of detection, though factors were highly interdependent. Analysis of recaptured bats suggests that viral clearance may occur within one month. These findings may be implemented in the development of risk reduction strategies for potential zoonotic coronavirus transmission.

Factors associated with household transmission of SARS-CoV-2 omicron variant to health care workers: A retrospective cohort study.

The aim of this study was to determine the risk factors for household transmission of the omicron variant of SARS-CoV-2. The household infection rate has been reported to be higher for the omicron variant than for non-omicron variants of SARS-CoV-2. Determination of the risk factors for household transmission of the omicron variant is therefore important. A Retrospective Cohort Study was conducted. When family members of health care workers (HCWs) were found to be infected with SARS-CoV-2, the HCWs had to receive two nucleic acid amplification tests for SARS-CoV-2: immediately after and 5 to 10 days after the onset of COVID-19 in the family members. Risk factors of household transmission were analysed by comparing cases (HCWs infected with SARS-CoV-2) and controls (HCWs not infected with SARS-CoV-2) using multivariable analysis. Unvaccinated status (OR: 3.97), age of index cases (≤6 years) (OR: 1.94) and staying at home with index cases (OR: 10.18) were risk factors for household transmission. If there is a strong desire to avoid household infection, family members infected with SARS-CoV-2 should live separately during the period of viral shedding.

Information-Based Sensor Placement for Data-Driven Estimation of Unsteady Flows

Estimation of unsteady flowfields around flight vehicles may improve flow interactions and lead to enhanced vehicle performance. Although flowfield representations can be very high-dimensional, their dynamics can sometimes have low-order representations that may be estimated using a few, appropriately placed measurements. This paper presents a sensor-selection framework for the intended application of data-driven, flowfield estimation. This framework combines data-driven modeling, steady-state Kalman filter design, and sparse, sequential sensor selection. This paper also uses the sensor selection framework to design sensor arrays that can perform well for a collection of operating conditions. Flow estimation results on numerical data show that the proposed framework produces arrays that are highly effective at flowfield estimation for the flow behind and an airfoil at a high angle of attack using embedded pressure sensors. Analysis of the flowfields reveals that paths of impinging stagnation points along the airfoil’s surface during a shedding period of the flow are highly informative locations for placement of pressure sensors.

SARS-CoV-2 Seroprevalence Studies in Pets, Spain.

SARS-CoV-2 can infect domestic animals such as cats and dogs. The zoonotic origin of the disease requires surveillance on animals. Seroprevalence studies are useful tools for detecting previous exposure because the short period of virus shedding in animals makes detection of the virus difficult. We report on an extensive serosurvey on pets in Spain that covered 23 months. We included animals with exposure to SARS-CoV-2-infected persons, random animals, and stray animals in the study. We also evaluated epidemiologic variables such as human accumulated incidence and spatial location. We detected neutralizing antibodies in 3.59% of animals and showed a correlation between COVID-19 incidence in humans and positivity to antibody detection in pets. This study shows that more pets were infected with SARS-CoV-2 than in previous reports based on molecular research, and the findings highlight the need to establish preventive measures to avoid reverse zoonosis events.

Minimal vertical transmission of Equid alphaherpesvirus 1 (EHV-1) in normal developing foals during a naturally occurring abortion outbreak

Equid alphaherpesvirus 1 (EHV-1) is a major cause of abortion or neonatal death in horses worldwide. Using an experimental EHV-1 abortion model, only a fraction of mares aborted and the remaining foals were delivered normally, with a normal neonatal development beyond day 10 (Gardiner et al. Vaccine 2012;30:6564-72). Interestingly, high EHV-1 (genome) abundance was identified in the fetal membranes of the normal foals. It was suggested that vertical viral transmission from dam to foal had occurred without apparent impairment of the foal. During a vast EHV-1 abortion outbreak among approximately 1000 broodmares on a single operation, approximately one quarter of the expected foal crop was lost. There were (late trimester) abortions or foals that died/were euthanized within 24 hours postpartum (pp) due to severe respiratory distress syndrome (group 1). There was a (for this farm) disproportionally large group of foals that died or were euthanized due to signs of maladjustment/placental insufficiency within 96 hours after parturition (group 2). Normal foals were also born which lived beyond 10 days without complications (group 3). Our aim was to test the following hypothesis, namely whether there is evidence of natural vertical EHV-1 transmission in foals with uncomplicated parturitions and normal pp development during an abortion outbreak. During this EHV-1abortion outbreak, we collected fetal membranes from any pregnancy outcome of groups 1 – 3. With pregnancies grouped according to gestational age in paddocks of 40 - 50 mares, unfavorable pregnancy outcome varied between paddocks. To avoid sampling bias, we matched for any group 1 or 2 pregnancy outcome within the same paddock with two group 3 outcome samples. Samples were fixed in formaldehyde and paraffin embedded. Tissue sections were prepared for DNA extraction, and EHV-1 genome abundance was determined by semiquantitative PCR assay (Hussey.et.al. J Vet Diagn Invest. 2006;18:335-42). Results were reported as ‘moderate abundance’ at cycle threshold (CT) <34; ‘low’ at CT (34-37), and negligible at CT>37-39. Samples were considered ‘undetectable’ if CT≥39. Viral genome copy numbers are reported as (moderate/low/negligible) abundance and the total number of samples per group. In group 1 abundance was 2/9/1 in 22 samples (54.4%); group 2: 0/3/0 in 15 samples (20.0%), and 0/2/4 in 85 samples (7.1%) in group 3. We conclude that there is minimal vertical EHV-1 carry-over in those foals that develop normally post-partum during an EHV-1 abortion outbreak. Whether carry-over is limited to the fetal membranes or whether EHV-1 reaches the respiratory tract for a productive period of shedding in the foals could now be investigated.

Economic and environmental analysis of a grid-connected hybrid power system for a University Campus

BackgroundThe generation of clean and affordable energy by 2030 is a challenging task, necessitating the integration of renewable energy sources to reduce greenhouse gas emissions associated with coal, crude oil, and natural gas. This study examines the optimization and performance analysis of a hybrid microgrid for a university campus as a potential solution to achieve this goal. The primary objective is to decrease the cost of energy and reduce CO2 emissions on the campus using a hybrid approach.ResultsThe Howard college campus of the University of KwaZulu Natal (UKZN) was used as a case study, with meteorological data obtained from NASA and real hourly electrical load data for 2019 from the university smart meters. HOMER, an optimization software, was employed to model and simulate the case study. The results demonstrated significant savings of R15.7 million (approximately $ 820 000) in annual utility bills, a 51% reduction in CO2 emissions, a return on investment of 20%, and a payback period of 4 years.ConclusionThe study's findings suggest that universities can become self-sustaining during load shedding periods, as recently experienced in South Africa. The implementation of a hybrid microgrid system on a university campus offers considerable economic and environmental benefits, providing a potential blueprint for other large institutions seeking to achieve similar sustainability goals.

Investigation of symptoms and lesions of chickens infected with Eimeria species at low infectious doses

The study aimed to determine the prevalence, symptoms and lesions of coccidiosis in chickens experimentally infected with coccidial oocysts at low doses. Chickens (n = 40, 14 days old, coded MD02 from Minh Du company) were randomly assigned to four equal groups. Group 1, group 2 and group 3 chickens were orally inoculated with 1, 10 &amp; 300 isolated oocysts of Eimeria species, respectively. Meanwhile, the chickens in group 4 were inoculated with phosphate-buffered saline as the control. Chickens in each treatment were raised individually. Fecal samples were collected individually every day after infection for oocysts counting. The results showed that chickens were infected with coccidial oocysts and had typical symptoms and lesions, even chickens were inoculated with one oocyst only. The prevalence of coccidiosis increased gradually with increasing levels of infectious dose, reaching 100% in group 3. The period of oocyst shedding was from 4 to 10 days post-inoculation. The number of oocysts was highest on day 6 post-inoculation. The oocyst counts were positively correlated with the infectious dose. Symptoms of anorexia, lethargy, wing drop and whitish, watery and bloody diarrhea were observed in infected chickens. The major lesions recorded were hemorrhages in the ceca (75 - 100%) and small intestines (100%).

Clinical features of Omicron variant infection in 445 patients with coronavirus 19 disease.

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) can mutate frequently and many new strains have emerged thus far. The clinical and epidemiological characteristics differ with each dominant strain. Obtain an understanding of the clinical characteristics of patients infected with the Omicron variants of the SARS CoV-2. Retrospective cohort SETTINGS: Teaching hospital in China. Data on sociodemography, signs/symptoms, hospital stay, viral shedding period, comorbidities, treatment options and final outcome were retrieved from hospital electronic medical record. We collected nasopharyngeal samples, laboratory data, and clinical data from patients admitted to the hospital with SARS CoV-2. Clinical characteristics of the patients infected with Omicron variant of SARS CoV-2. 445 patients RESULTS: The median age was 43.0 years with a range from 2 to 75 years. Two-thirds of the participants were male and one-third were female. Almost half of the participants (51.9%) had no symptoms, whereas 48.1% had at least one symptom. Of symptomatic patients, 26.7% had mild symptoms and 21.3% had moderate symptoms. No patients were admitted with severe or critical symptoms. All patients discharged from the hospital after complete recovery without any serious complications or death. The most common symptom was cough followed by sore throat and fever. Less common symptoms were having sputum, stuffy nose, and muscle pain. Rare symptoms were weakness, headache, diarrhea, hemoptysis and nausea/vomiting. All patients had mild to moderate symptoms. Shortness of breath was not a common symptom among the study group. No patients needed invasive oxygen therapy in this cohort. Single center and retrospective design. None.

Co-planning of transmission and energy storage by iteratively including extreme periods in time-series aggregation

The co-planning problem of transmission and energy storage system (ESS) requires a large amount of historical and forecasted input data to account for the volatility of renewable energy and loads. However, the large input data usually make the planning problem difficult to solve, so time series aggregation is often used to reduce the computational complexity. Nevertheless, it is difficult to guarantee the reliability of operation on the whole input data. Therefore, this paper proposes an iterative method to select extreme scenarios, and designs two indicators to select extreme scenarios, considering the system power balance and peak shaving capacity situation. Based on these two indicators, the periods of maximum load shedding and the periods of maximum renewable energy curtailment will be selected as extreme scenarios in the results of the operational optimization problem. We iteratively add extreme scenarios to the set of scenarios of the planning problem until the reliability of system operation can be adequately met. At the same time, in order to ensure the effectiveness of extreme scenarios, the operation statuses of thermal units in those periods are also taken into account. Our method is tested on an IEEE RTS-24 system with some modification. The results show that our method can guarantee the reliability of the whole system and is superior to the method that simply selects extreme scenarios. Meanwhile, we also perform a sensitivity analysis of the price of energy storage.

Comparison of culture-competent virus shedding duration of SARS-CoV-2 Omicron variant in regard to vaccination status: A prospective cohort study.

Previous studies have shown that fully vaccinated patients with SARS-CoV-2 Delta variants has shorter viable viral shedding period compared to unvaccinated or partially vaccinated patients. However, data about effects of vaccination against the viable viral shedding period in patients with SARS-CoV-2 Omicron variants were limited. We compared the viable viral shedding period of SARS-CoV-2 omicron variant regard to vaccination status. Saliva samples were obtained daily from patients with SARS-CoV-2 Omicron variant, and genomic assessments and virus culture was performed to those samples. We found no difference in viable viral shedding period between fully vaccinated and not or partially vaccinated, nor between 1st boostered vs non-boostered patients with SARS-CoV-2 Omicron variant.