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    Profiling pre-symptomatic and asymptomatic TRANS cases with confirmed TRANS SARS-CoV-2 infection MESHD in Mexico City

    Authors: Omar Yaxmehen Bello-Chavolla; Neftali Eduardo Antonio-Villa; Arsenio Vargas-Vázquez; Carlos A. Fermín-Martínez; Alejandro Márquez-Salinas; Jessica Paola Bahena-López

    doi:10.1101/2020.07.02.20145516 Date: 2020-07-04 Source: medRxiv

    BACKGROUND: Asymptomatic TRANS SARS-CoV-2 infections MESHD are potential sources for transmission TRANS. OBJECTIVES: Here, we aimed to profile pre-symptomatic/ asymptomatic TRANS SARS-CoV-2 infections MESHD in Mexico City, its associated comorbidities and outcomes. METHODS: Prospective observational study of SARS-CoV-2 cases assessed by contact tracing TRANS within the National Epidemiological Surveillance System in Mexico City. We classified subjects as cases with and without respiratory and non-respiratory symptoms ( RS MESHD, NRS, respectively) assessed for SARS-CoV-2 using real time RT-PCR from nasopharyngeal swabs to evaluate clinical characteristics as well as features associated with severe COVID-19. RESULTS: Amongst 80735 cases with confirmed TRANS SARS-CoV-2 infection MESHD as of July 23th, 2020, we identified 9659 cases without RS MESHD (12.0%), 5605 had only NRS (6.9%) and 4054 who were initially asymptomatic TRANS (5.1%). Compared to asymptomatic TRANS cases, those with NRS and those with RS MESHD+NRS had higher rates of severe COVID-19 outcomes including hospitalization, ICU admission, and intubation (p<0.001). Mortality was higher for cases with RS MESHD+NRS (HR 7.58, 95%CI 4.56-12.58) or NRS (HR 3.13, 95%CI 1.80-5.45) compared to asymptomatic TRANS cases, adjusted for age TRANS, sex and comorbidities. Predictors for mortality in asymptomatic TRANS SARS-Co-V-2 infections MESHD infections, chronic HP chronic kidney disease MESHD, previous exposure with suspected infection MESHD cases and older age TRANS were predictors for lethality. CONCLUSIONS: Definition of pre-symptomatic/ asymptomatic TRANS cases has relevant implications for SARS-CoV-2 infection MESHD outcomes. Older age TRANS and comorbidity impact on the probability of developing severe complications for cases who were asymptomatic TRANS or had only NRS at evaluation and were sent for domiciliary treatment. Extending testing for detection of asymptomatic TRANS cases must be considered in Mexico to better understand the impact of the pandemic.

    Factors Affecting SARS-CoV-2 (COVID-19) Pandemic, including Zoonotic, Human Transmission and Chain TRANS of Infection. Reducing Public Health Risk by Serum SERO Antibody Testing SERO, Avoiding Screening in Unhygienic Places and False PCR Reporting. A Scientific Review

    Authors: Kamran Mahmood Ahmed Aziz; Abdullah Othman; Waleed Alqahtani; Sumaiya Azhar

    id:10.20944/preprints202006.0284.v1 Date: 2020-06-23 Source: Preprints.org

    Since December 2019, a rapid increase in the number of SARS-CoV-2 (COVID-19) cases was reported worldwide, despite strict infection control and lock down measures. Current paper investigated the actual facts behind this rapid increase in the number of cases. Study of genomic sequence reveals that domestic and wild animals were likely ancestors and zoonotic source for SARS-CoVs MESHD, MERS-CoVs, and SARS-CoV-2. Strong evidence suggest that these viruses already existed and replicated in animals and humans during past several decades, exhibiting diverse mutations, evolutions and self-limiting diseases, except during outbreaks. Serious zoonotic reservoir investigations are required to investigate animal transmission TRANS of SARS-CoVs and SARS-CoV-2 MESHD to limit current pandemic. This might be the reason of increasing number of cases via animals. SARS-CoV-2 has been retrospectively isolated in different studies in August 2019, several months before Wuhan announced. Hence, there is a possibility that viruses existed, went undetected, infecting subclinically, in past several years, and SARS-CoV-2 antigens and neutralizing antibodies SERO may have been present in humans since long time. This might be another reason of increasing number of cases by screening as mass screening and antigen or antibody testing SERO was not carried out in the past years. Randomized controlled trials are required to investigate human to human transmission TRANS by touch, as the current evidence is limited with conflicting results. As all SARS-CoVs MESHD are basically respiratory viruses, droplet precautions and infection MESHD control measures are essential, especially for hospital staff. Increased number of SARS-CoV-2 asymptomatic TRANS, or subclinical cases are detected worldwide. This silent phase of transmission TRANS can be beneficial for humans. Lack of symptoms eventually lessen virus transmission TRANS and reduce the pathogen's long-term survival and provide humoral herd immunity up to several years. Hence, seropositivity with diverse antibodies SERO develops against mutating SARS-CoVs which will confer strong immunity during epidemics. Strategies such as identification, contact tracing TRANS and quarantine are costly and practically difficult. Hence, asymptomatic TRANS persons can continue their work with droplet precautions and standard infection control procedures, while symptomatic or sick persons can isolate themselves in their homes without the need for strict quarantine until clinical recovery, with reduced hospital visits and minimizing chances of hospital acquired infections. RT-PCR has low sensitivity SERO and specificity, carries a high risk of handling live virus antigens, and requires difficult protocols. As viral load also sharply declines after few days of onset of infection MESHD, this technique might overlook infection MESHD. Furthermore, SARS-CoV-2 infection MESHD may be present in blood SERO when oropharyngeal swabs are negative by RT-PCR. Additionally, RT-PCR usually gives false negative and false positive results and must be interpreted cautiously. This might be again a reason of increasing number of cases by false positive RT-PCR reporting. Moreover, antibodies SERO against SARS-CoVs develop robustly in serum SERO even by reduced amount of antigens. In contrast to RT-PCR, ELISA SERO for diagnosing antibodies SERO against SARS-CoV-2 demonstrates 100% specificity and 100% sensitivity SERO, even in clinically asymptomatic TRANS individuals. These antibodies SERO can be used for serologic surveys SERO, monitoring and screening. However, screening tests for SARS-COV-2 should be avoided in unhygienic public places by nasopharyngeal swabs, which carry a high risk of further transmission TRANS, co-infection MESHD or superinfection. Such highly infectious virus must be isolated and tested in highly sterilized laboratory. Further strict international laws and policies are required to stop the possible spread of experimental viruses, biological warfare and bioterrorism.

    High viral load suggests increased COVID-19 severity in a longitudinal cohort

    Authors: Yuanlin He; Xin Xu; Qun Lu; Zhiliang Hu; Yue Jiang; Ci Song; Wei Chen; Peipei Li; Weixiao Wang; Chuanjun Xu; Yuting Ma; Yuan Lin; Zhibin Hu; Yongxiang Yi; Hongbing Shen

    doi:10.21203/rs.3.rs-34267/v1 Date: 2020-06-08 Source: ResearchSquare

    Background: An outbreak caused by the 2019 novel coronavirus (2019-nCoV) has spread globally. However, the viral dynamics, co-infection MESHD and their associations with clinical severity, have not been well explored.Methods: We longitudinally enrolled 23 (Five severe-type, ten common-type and eight asymptomatic TRANS-type patients) hospitalized 2019-nCov-infected patients in Jiangsu between January 21 and February 11, 2020. Medical records and pharyngeal swab specimens, were collected to analyze the association between viral dynamic and disease severity.Results: Five severe-type, ten common-type and eight asymptomatic TRANS-type patients were enrolled. Linear mixed effects models revealed that the common and severe-type patients had a higher level of viral load (3.08 points, 95% CI, 0.51-5.65, P = 0.019; 6.07 points, 95% CI, 2.79-9.35, P < 0.001) and maintained a higher peak viral load ( P = 0.066 and 0.022, respectively), when compared with the asymptomatic TRANS group. Viral load shedding among older patients ( aged TRANS ≥ 60) processed slower than that among younger patients ( P = 0.047). RNA virome sequencing identified two co-infected MESHD RNA viruses, Human endogenous retrovirus H (HERV) and Human picobirnavirus (HPBV). Of note, HPBV was detected in one severe-type and two common-type patients, while was not detected in all the asymptomatic TRANS cases.Conclusion: Higher viral load was positively associated with disease severity. This finding highlights the importance of monitoring the viral kinetics to identify patients at greater risk of progressing to severe pneumonia HP pneumonia MESHD.

    SARS-CoV-2 infection MESHD, clinical features and outcome of COVID-19 in United Kingdom nursing homes

    Authors: Neil SN Graham; Cornelia Junghans; Rawlda Downes; Catherine Sendall; Helen Lai; Annie McKirdy; Paul Elliott; Robert Howard; David Wingfield; Miles Priestman; Marta Ciechonska; Loren Cameron; Marko Storch; Michael Crone; Paul Freemont; Paul Randell; Robert McLaren; Nicola Lang; Shamez Ladhani; Frances Sanderson; David J Sharp

    doi:10.1101/2020.05.19.20105460 Date: 2020-05-26 Source: medRxiv

    Objectives: To understand SARS-Co-V-2 infection MESHD and transmission TRANS in UK nursing homes in order to develop preventive strategies for protecting the frail elderly TRANS residents. Design: An outbreak investigation. Setting: 4 nursing homes affected by COVID-19 outbreaks in central London. Participants: 394 residents and 70 staff in nursing homes. Interventions: Two point- prevalence SERO surveys one week apart where residents underwent SARS-CoV-2 testing and had relevant symptoms documented. Asymptomatic TRANS staff from three of the four homes were also offered SARS-CoV-2 testing. Main outcome measures: All-cause mortality, and mortality attributed to COVID-19 on death certificates. Prevalence SERO of SARS-CoV-2 infection MESHD and symptoms in residents and staff. Results: Overall, 26% (95% confidence interval 22 to 31) of residents died over the two-month period. All-cause mortality increased by 203% (95% CI 70 to 336). Systematic testing identified 40% (95% CI 35 to 46) of residents, of whom 43% (95% CI 34 to 52) were asymptomatic TRANS and 18% (95% CI 11 to 24) had atypical symptoms, as well as 4% (95% CI -1 to 9) of asymptomatic TRANS staff who tested positive for SARS-CoV-2. Conclusions: The SARS-CoV-2 outbreak was associated with a very high mortality rate in residents of nursing homes. Systematic testing of all residents and a representative sample of staff identified high rates of SARS-CoV-2 positivity across the four nursing homes, highlighting a potential for regular screening to prevent future outbreaks.

    What do we know about SARS-CoV-2 transmission TRANS? A systematic review and meta-analysis of the secondary attack rate TRANS, serial interval TRANS, and asymptomatic TRANS infection MESHD

    Authors: Wee Chian Koh; Lin Naing; Muhammad Ali Rosledzana; Mohammad Fathi Alikhan; Liling Chaw; Matthew Griffith; Roberta Pastore; Justin Wong

    doi:10.1101/2020.05.21.20108746 Date: 2020-05-23 Source: medRxiv

    Background Current SARS-CoV-2 containment measures rely on the capacity to control person-to-person viral transmission TRANS. Effective prioritization of these measures can be determined by understanding SARS-CoV-2 transmission TRANS dynamics. We conducted a systematic review and meta-analyses of three parameters: (i) secondary attack rate TRANS ( SAR TRANS) in various settings, (ii) clinical onset serial interval TRANS (SI), and (iii) the proportion of asymptomatic TRANS infection MESHD. Methods and Findings We searched PubMed, medRxiv, and bioRxiv databases between January 1, 2020, and May 15, 2020, for articles describing SARS-CoV-2 attack rate TRANS, SI, and asymptomatic TRANS infection MESHD. Studies were included if they presented original data for estimating point estimates and 95% confidence intervals of the three parameters. Random effects models were constructed to pool SAR TRANS, mean SI, and asymptomatic TRANS proportion. Risk ratios were used to examine differences in transmission risk TRANS by setting, type of contact, and symptom status of the index case. Publication and related bias were assessed by funnel plots and Egger's meta-regression test for small-study effects. Our search strategy for SAR TRANS SAR MESHD, SI, and asymptomatic TRANS infection MESHD identified 459, 572, and 1624 studies respectively. Of these, 20 studies met the inclusion criteria for SAR TRANS, 18 studies for SI, and 66 studies for asymptomatic TRANS infection MESHD. We estimated the pooled household SAR TRANS at 15.4% (95% CI: 12.2%, 18.7%) compared to 4.0% (95% CI: 2.8%, 5.2%) in non-household settings. We observed variation across settings; however, the small number of studies limited power to detect associations and sources of heterogeneity. SAR TRANS of symptomatic index cases is significantly higher than cases that were symptom-free at diagnosis (RR 2.55, 95% CI: 1.47, 4.45). Adults TRANS appear to be more susceptible to transmission TRANS than children TRANS (RR 1.40, 95% CI: 1.00, 1.96). The pooled mean SI is estimated at 4.87 days (95% CI: 3.98, 5.77). The pooled proportion of cases who had no symptoms at diagnosis is 25.9% (95% CI: 18.8%, 33.1%). Conclusions Based our pooled estimates, 10 infected symptomatic persons living with 100 contacts would result in 15 additional cases in <5 days. To be effective, quarantine of contacts should occur within 3 days of symptom onset TRANS. If testing and tracing TRANS relies on symptoms, one-quarter of cases would be missed. As such, while aggressive contact tracing TRANS strategies may be appropriate early in an outbreak, as it progresses, control measures should transition to account for SAR TRANS variability across settings. Targeted strategies focusing on high-density enclosed settings may be effective without overly restricting social movement.

    A Mini Review on Current Clinical and Research Findings for Children TRANS Suffering from COVID-19

    Authors: Xiao Li; Kun Qian; Ling-ling Xie; Xiu-juan Li; Min Cheng; Li Jiang; Bjoern W. Schuller

    doi:10.1101/2020.03.30.20044545 Date: 2020-04-04 Source: medRxiv

    Background: As the novel coronavirus triggering COVID-19 has broken out in Wuhan, China and spread rapidly worldwide, it threatens the lives of thousands of people and poses a global threat on the economies of the entire world. However, infection MESHD with COVID-19 is currently rare in children TRANS. Objective To discuss the latest findings and research focus on the basis of characteristics of children TRANS confirmed with COVID-19, and provide an insight into the future treatment and research direction. Methods: We searched the terms "COVID-19 OR coronavirus OR SARS-CoV-2" MESHD AND "Pediatric OR children TRANS" on PubMed, Embase, Cochrane library, NIH, CDC, and CNKI. The authors also reviewed the guidelines published on Chinese CDC and Chinese NHC. Results: We included 25 published literature references related to the epidemiology, clinical manifestation, accessary examination, treatment, and prognosis of pediatric patients with COVID-19. Conclusion: The numbers of children TRANS with COVID-19 pneumonia HP pneumonia MESHD infection are small, and most of them come from family aggregation. Symptoms are mainly mild or even asymptomatic TRANS, which allow children TRANS to be a risk factor for transmission TRANS. Thus, strict epidemiological history screening is needed for early diagnosis and segregation. This holds especially for infants, who are more susceptible to infection MESHD than other age groups TRANS in pediatric age TRANS, but have most likely subtle and unspecific symptoms. They need to be paid more attention to. CT examination is a necessity for screening the suspected cases, because most of the pediatric patients are mild cases, and plain chest X-ray do not usually show the lesions or the detailed features. Therefore, early chest CT examination combined with pathogenic detection is a recommended clinical diagnosis scheme in children TRANS. The risk factors which may suggest severe or critical progress for children TRANS are: Fast respiratory rate and/or; lethargy HP and drowsiness HP mental state and/or; lactate progressively increasing and/or; imaging showed bilateral or multi lobed infiltration, pleural effusion HP pleural effusion MESHD or rapidly expending of lesions in a short period of time and/or; less than 3 months old or those who underly diseases. For those critical pediatric patients with positive SARS-CoV-2 diagnosis, polypnea may be the most common symptom. For treatment, the elevated PCT seen in children TRANS in contrast to adults TRANS suggests that the underlying coinfection/ secondary infection MESHD may be more common in pediatric patients and appropriate antibacterial treatment should be considered. Once cytokine storm is found in these patients, anti-autoimmune or blood SERO-purifying therapy should be given in time. Furthermore, effective isolation measures and appropriate psychological comfort need to be provided timely.

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MeSH Disease
Human Phenotype
Transmission
Seroprevalence


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