Rate Of Asymptomatic Infection Research Articles

Tenofovir-based PrEP for COVID-19: an untapped opportunity?

Tenofovir-based PrEP for COVID-19: an untapped opportunity?

The seroprevalence of SARS-CoV-2 among residents of the Khabarovsk Krai during the COVID-19 epidemic

Introduction. The coronavirus disease (COVID-19) pandemic was announced by WHO in February 2020. In the Khabarovsk Krai, the first three cases of the disease were diagnosed on March 19, 2020, these cases were imported from Argentina (transit through Italy). The epidemic process of COVID-19 in the Khabarovsk Krai is characterized by a slow increase in the incidence. During the period of time when the SARS-CoV-2 seroprevalence study was conducted the incidence rates varied from 35.9 to 39.1 per 100 thousand population. Within the next 5 weeks the incidence continued to increase, the maximum level was 67.3 per 100 thousand population. A statistically significant decrease in the incidence is noted in the first decade of August. The study of the SARS-CoV-2 seroprevalence among residents of the region was carried out from June 9 to June 21, 2020 during the period of increasing intensity of the epidemic process of COVID-19 infection.Aim. To determine the level and structure of herd immunity to SARS-CoV-2 virus among the population of the Khabarovsk Krai during the period of intensive spread of COVID-19.Materials and methods. The study was conducted as a part of the first stage of a large-scale Rospotrebnadzor project to assess the herd immunity to SARS-CoV-2 virus among the population of the Russian Federation, taking into consideration the protocol recommended by WHO. The selection of volunteers for the study was carried out by the method of questionnaires and randomization by random sampling. The results of a survey of 2675 individuals were included into analysis. The number of volunteers in all age groups was similar.Results. The results of the study showed that the herd immunity to SARS-CoV-2 in the total population of the Khabarovsk Krai was 19.6%. The maximum level of herd immunity was observed in children 14–17 years old (34.4%), children 7–13 years old (24.8%), and people over 70 years (22.6%). The highest level of seropositivity, except for the children and the elderly, was found among educational workers (26.7%). The lowest level of seropositivity was found in the military (8.7%) and the unemployed (8.3%). There were no statistically significant differences in the level of seroprevalence between men and women.Conclusions. The results of the seroepidemiological study demonstrated that in the Khabarovsk Krai, the presence of the contacts with COVID-19 patients is associated with the 1.4-fold increase in the likelihood of the seroconversion. Antibodies were detected in 58.9% of the past COVID-19 cases. In individuals with the previous positive PCR test result, antibodies were detected in 50% of cases. A high rate of asymptomatic infection, up to 93.7%, was observed among seropositive volunteers.

COVID-19 Antibodies and Outcomes among Outpatient Maintenance Hemodialysis Patients.

Patients on maintenance hemodialysis are particularly vulnerable to infection and hospitalization from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Due to immunocompromised patients and the clustering that occurs in outpatient dialysis units, the seroprevalence of COVID-19 antibodies in this population is unknown and has significant implications for public health. Also, little is known about their risk factors for hospitalization. Three outpatient maintenance hemodialysis units affiliated with a major teaching hospital in the New York area were studied. We determined rates of SARS-CoV-2 positivity via nasopharyngeal, real-time, reverse-transcriptase PCR (RT-PCR); SARS-CoV-2 IgG seropositivity; hospitalization; and mortality. Of 367 patients, 28% had either SARS-CoV-2 seropositivity or PCR positivity. Prevalence across the three respective units was 7%, 32%, and 70%. Those who were either antibody or PCR positive were significantly younger (65 versus 69 years, P=0.05), and had a higher prevalence of Black race (43% versus 30%, P=0.001) and Hispanic ethnicity (32% versus 12%, P<0.001) compared with those who tested negative. Higher positivity rates were also observed among those who took taxis and ambulettes to and from dialysis, compared with those who used personal transportation. Antibodies were detected in all of the patients with a positive PCR result who underwent serologic testing. Of those that were seropositive, 32% were asymptomatic. The hospitalization rate on the basis of either antibody or PCR positivity was 35%, with a hospital mortality rate of 33%. Aside from COPD, no other variables were more prevalent in patients who were hospitalized. We observed significant differences in rates of COVID-19 infection within three outpatient dialysis units, with universal seroconversion. Among patients with ESKD, rates of asymptomatic infection appear to be high, as do hospitalization and mortality rates.

Nasal interferon responses to community rhinovirus infections are similar in controls and children with asthma

BackgroundRhinovirus (RV) is the main cause of asthma exacerbations in children. Some studies reported that persons with asthma have attenuated interferon (IFN) responses to experimental RV infection compared with healthy individuals. However, responses to community-acquired RV infections in controls and children with asthma have not been compared. ObjectiveTo evaluate nasal cytokine responses after natural RV infections in people with asthma and healthy children. MethodsWe compared nasal cytokine expression among controls and children with asthma during healthy, virus-negative surveillance weeks and self-reported RV-positive sick weeks. A total of 14 controls and 21 patients with asthma were studied. Asthma disease severity was based on symptoms and medication use. Viral genome was detected by multiplex polymerase chain reaction. Nasal cytokine protein levels were determined by multiplex assays. ResultsTwo out of 47 surveillance weeks tested positive for RV, illustrating an asymptomatic infection rate of 5%. A total of 38 of 47 sick weeks (81%) tested positive for the respiratory virus. Of these, 33 (87%) were positive for RV. During well weeks, nasal interleukin 8 (IL-8), IL-12, and IL-1β levels were higher in children with asthma than controls. Compared with healthy virus-negative surveillance weeks, IL-8, IL-13, and interferon beta increased during colds only in patients with asthma. In both controls and children with asthma, the nasal levels of interferon gamma, interferon lambda-1, IL-1β, IL-8, and IL-10 increased during RV-positive sick weeks. During RV infection, IL-8, IL-1β, and tumor necrosis factor-α levels were strongly correlated. ConclusionIn both controls and patients with asthma, natural RV infection results in robust type II and III IFN responses.

Infection and transmission of SARS-CoV-2 in London care homes reporting no cases or outbreaks of COVID-19: Prospective observational cohort study, England 2020.

BackgroundCare homes have been disproportionately affected by the COVID-19 pandemic. We investigated the potential role of asymptomatic infection and silent transmission in London care homes that reported no cases of COVID-19 during the first wave of the pandemic.MethodsFive care homes with no cases and two care homes reporting a single case of COVID-19 (non-outbreak homes) were investigated with nasal swabbing for SARS-CoV-2 RT-PCR and serology for SARS-CoV-2 antibodies five weeks later. Whole genome sequencing (WGS) was performed on RT-PCR positive samples. Serology results were compared with those of six care homes with recognised outbreaks.FindingsAcross seven non-outbreak homes, 718 (387 staff, 331 residents) individuals had a nasal swab and 651 (386 staff, 265 residents) had follow-up serology. Sixteen individuals (13 residents, 3 staff) in five care homes with no reported cases were RT-PCR positive (care home positivity rates, 0 to 7.6%) compared to 13 individuals (3.0 and 10.8% positivity) in two homes reporting a single case.Seropositivity across these seven homes varied between 10.7-56.5%, with four exceeding community seroprevalence in London (14.8%). Seropositivity rates for staff and residents correlated significantly (rs 0.84, [95% CI 0.51-0.95] p <0.001) across the 13 homes. WGS identified multiple introductions into some homes and silent transmission of a single lineage between staff and residents in one home.InterpretationWe found high rates of asymptomatic infection and transmission even in care homes with no COVID-19 cases. The higher seropositivity rates compared to RT-PCR positivity highlights the true extent of the silent outbreak.FundingPHE

An Epidemiological Cohort Study of SARS-CoV-2 and COVID-19 in German Healthcare Workers – Interim Analysis After Six Months of Follow-Up

Background: Healthcare workers (HCWs) are at increased risk of SARS-CoV-2 infection. We followed a large cohort of HCWs in Germany to assess the incidence of SARS-CoV-2 infection and COVID-19 disease before the introduction of COVID-19 vaccines.Methods: We present interim data, collected from August 2020 to January 2021 in the ′CPMprevac′ study, an ongoing prospective observational cohort study including HCWs at the University Medical Centre of Mainz in Germany. Antibody status was assessed at baseline and every 6 weeks (±2 weeks). Daily self-reported COVID-19 symptoms were collected using a smartphone application, and symptomatic HCWs were tested using RT-PCR. We estimated the rates of symptomatic and asymptomatic SARS-CoV-2 infections. The rates of confirmed COVID-19 disease were estimated based on two case definitions of varying sensitivity and specificity.Findings: 3664 HCWs were enrolled in the study with a median follow-up of 101 days. The seroprevalence of anti-SARS-CoV-2 IgM and/or IgG increased from 2·7% at baseline to 3·8%, with the number of seroconversions (65) outweighing seroreversions (26) by the end of follow-up. Among HCWs who seroconverted, 12 (~19%) did not report any symptoms. The incidence rate was estimated to be 4·5 per 1000 person-months. Among the 53 incident cases, none developed severe COVID-19 disease, however, one subject (1·8%) was hospitalized. The most common symptom reported was smell or taste dysfunction, with or without other symptoms. With a median follow up of 100 days, anti-SARS-CoV-2 antibodies fell below diagnostic cut-off value in a third of those positive at baseline and in only one incident case.Interpretation: We observed increasing rates of COVID-19 disease infections among HCWs during a period of accelerated community transmission. The rate of asymptomatic infections, however, was lower than estimates from cross-sectional studies. Nearly one third of seropositive HCWs at baseline reverted by the end of follow-up, however, we did not detect evidence of reinfection.Registration: European Union’s electronic register of Post-Authorisation Studies (EU PAS register number EUPAS37174).Funding: This study was funded by CureVac AG, Tübingen, Germany.Declaration of Interests: Thomas Verstraeten is the managing director of P95, and also a paid consultant at CureVac AG, fulfilling the role of Safety Physician. Stephan Gehring and Frank Kowalzik are employees of UM Mainz and in addition paid for this study as Principal Investigator and Co-Investigator, respectively, by CureVac AG. Omar Okasha, Anirudh Thomer and Wendy Hartig-Merkel are paid employees of P95 and state no conflict of interest. Lidia Oostvogels is a paid employee of CureVac AG.Ethics Approval Statement: The study was approved by the relevant Independent Ethical Committee (IEC; Ethik-Kommission bei der Landesärztekammer Rheinland-Pfalz, Germany).

Universal Sars-Cov-2 Screening in Pregnant Women: Experience from the Italian Epidemic Outbreak.

Background and aim:Sars-CoV-2 infection has rapidly spread worldwide following the first cases reported in China. Piacenza is one of the most affected cities in Italy. Many infections occurred in the hospital due to the high frequency of patients and healthcare professionals interaction. The aim of the work is to evaluate advantages of universal screening for Sars-Cov-2 in pregnant women admitted to a hospital setting and calculate frequency of infection in an obstetrical population.Methods:all pregnant women attending Guglielmo da Saliceto Hospital in Piacenza from 22nd April to 18th June 2020 were screened for Sars-Cov-2 using a nasopharyngeal swab.Results:240 pregnant women were tested upon admission: all twelve (5%) testing positive were asymptomatic. None of the positive asymptomatic women developed COVID-19 symptoms or adverse perinatal outcomes.Conclusions:the diagnosis of asymptomatic pregnant women through universal screening provides the opportunity to protect mothers, babies and heath care workers. In accordance with other studies, our findings add to the growing body of evidence showing high rates of asymptomatic infection in the healthcare setting and highlight a critical need for universal screening of pregnant women. (www.actabiomedica.it)

Assessment of global asymptomatic SARS-CoV-2 infection and management practices from China.

With ongoing research, it was found that asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was widespread in coronavirus disease 2019 (COVID-19) populations. Studies have confirmed asymptomatic patients with COVID-19 have potential infectivity, and most of the transmission occurred before symptoms appear. Asymptomatic infection rates varied widely in different countries and regions. Identifying the asymptomatic infected persons and cutting off the infection source is an effective way to prevent the spread of this disease. However, asymptomatic patients have hidden clinical symptoms, and screening based only on the clinical symptoms of COVID-19 can easily lead to a missed diagnosis. Therefore, determining asymptomatic infection patients by SARS-CoV-2 nucleic acid testing is the gold standard. A series of prevention and control measures adopted by the Chinese government, especially the “Four Early” policy, have achieved outstanding achievements, which are worth learning from by other countries.

BNT162b2 Vaccine Effectiveness in Preventing Asymptomatic Infection with SARS-CoV-2 Virus: A Nationwide Historical Cohort Study

Background: There is strong evidence regarding the efficacy and effectiveness of BNT162b2 vaccine in preventing symptomatic infection with SARS-CoV-2 virus. There is a paucity of data regarding effectiveness in prevention of asymptomatic infection. Methods: In this real-world study, we identified a sub-population of patients in a large health maintenance organisation who were repeatedly tested for SARS-CoV-2 infection using a PCR test. We used these patients as the cohort for the study, and compared individuals who were vaccinated with BNT162b2 mRNA vaccine to the unvaccinated ones. A positive SARS-CoV-2 PCR test result was used as the outcome. Follow-up period was from Jan 1,2021 until Feb 11, 2021. Findings: 6,286 individuals were included in the cohort. Seven days following the second vaccine dose, a rate of six positive PCR tests per 10,000 patient-days was recorded, compared with a rate of 53 positive tests per 10,000 patient-days for the unvaccinated group. The estimated vaccine effectiveness against infection with SARS-CoV-2 virus after two vaccine doses was 89% (confidence interval 82%-94%). The estimated effectiveness two weeks following the first vaccine dose was 61% (confidence interval 49%-71%). Interpretation: In this study, vaccination with BNT162b2 reduced infection rates among individuals who underwent screening by frequent SARS-CoV-2 PCR testing. Using a cohort of frequently tested individuals reduced the indication bias for the PCR testing, which enabled estimation of asymptomatic infection rates. Funding: This study received no funding. Declaration of Interests: DS reports receiving personal fees from Pfizer, outside the submitted work (advisory board on Trumenba); and Consultation fees from GSK and Gilead. The other authors declare no competing interests. Ethics Approval Statement: This study was approved by MHMO’s institutional review board number 03-17-02- 21, and investigators were exempt from requesting informed consent.

Universal SARS-CoV-2 Testing for Obstetric Inpatient Units Across the United States

Background: The purpose of this study was to estimate prevalence of asymptomatic SARS-CoV-2 infection among patients admitted to obstetric inpatient units throughout the United States as detected by universal screening. We sought to describe the relationship between obstetric inpatient asymptomatic infection rates and publicly available surrounding community infection rates. Methods: This was a cross-sectional study in which medical centers reported rates of positive SARS-CoV-2 testing in asymptomatic pregnant and immediate postpartum patients over a 1-3 month time span in 2020. Publicly reported SARS-CoV-2 case rates from the relevant county and state for each center were collected from the COVID Act Now dashboard and the COVID Tracking Project for correlation analysis. Findings: Data were collected from nine health centers, encompassing 18 hospitals. Participating health centers were located in Alabama, California, Illinois, Louisiana, New Jersey, North Carolina, Pennsylvania, Rhode Island, Utah, and Washington State. Each hospital had an active policy for universal SARS-CoV-2 testing on obstetric inpatient unit. A total of 10,147 SARS-CoV-2 tests were administered, of which 124 were positive (1·2%). Positivity rates varied by site, ranging from 0-3·2%. While SARS-CoV-2 infection rates were lower in asymptomatic obstetric inpatient groups than the surrounding communities, there was a positive correlation between positivity rates in obstetric inpatient units and their surrounding county (p=·003, r=·782) and state (p=·007, r=·708). Interpretation: Given the correlation between community and obstetric inpatient rates, the necessity of SARS-CoV-2 related healthcare resource utilization in obstetric inpatient units may be best-informed by surrounding community infection rates. Funding Information: Internal funding was used.Declaration of Interests: None to declare. Ethics Approval Statement: The study was IRB approved or determined exempt at each center.

The risk for severe COVID 19 in patients with autoimmune and/or inflammatory diseases: First wave lessons.

Data regarding the risk for severe COVID19 in patients with autoimmune or inflammatory diseases are scarce. To estimate the risk of those patients to develop a more severe COVID19 infection All active patients and those with dermatologic and/or rheumatologic autoimmune/inflammatory diseases were identified in a single tertiary center. The charts of those tested positive for COVID19 between 1 March 2020 and 31 May 2020 reviewed including demographics, co‐morbidities, and medications. COVID19 outcome of those with dermatologic and/or rheumatologic autoimmune/inflammatory diseases were compared to COVID19 infected matched controls without an autoimmune/inflammatory background. Overall, 974 of 381 268 active patients were tested positive for COVID19, including 35 out of 13 225 with dermatologic and/or rheumatologic autoimmune/inflammatory diseases. No statistically significant difference in severity of COVID19 infection or mortality rate was found. The rate of asymptomatic, mild, moderate, severe/critical and fatal COVID19 infection was 11.4%, 37.1%, 22.8%, 11.4%, and 17.1%, respectively, for the patients with autoimmune diseases and 17.8%, 45.8%, 10.9%, 6.8%, and 18.4%, respectively for the controls . Patients with autoimmune/inflammatory diseases seem not to develop a more severe COVID19 infection than controls.

Evaluation of the Clinical Features of 81 Patients with COVID-19: An Unpredictable Disease in Children

Abstract Objective Data on the prognosis of clinical features of pediatric patients affected by the coronavirus disease 2019 (COVID-19) pandemic is insufficient. This study aimed to examine the clinical, laboratory, and radiology findings of pediatric patients diagnosed with COVID-19. Methods A total of 81 pediatric patients with a confirmed diagnosis of COVID-19 who were admitted to the pediatric clinics of our tertiary care hospital in Istanbul between March 22 and May 1, 2020, were included in the study. Results Of the patients, 40 (49.6%) were boys and 41 (50.6%) were girls. The mean age of the patients was 9.3 ± 5.5 years (range: 1 month–16 years). The most common symptoms were cough (28.4%) and fever (25.9%). A total of 26 patients (32.1%) had pharyngeal erythema. There was no significant difference between age groups in terms of symptoms, findings, clinical picture, history of contact, and clinical course (p &gt; 0.001 for each). Abnormal findings were observed in seven (8.6%) patients on chest X-ray, and in four patients (4.9%) on thorax computed tomography. Only three of the patients were hospitalized and all of them discharged with healing. Conclusion The present study is the most comprehensive study on children diagnosed with COVID-19 in our country, which showed that the COVID-19 picture was mild in pediatric patients, but the signs and symptoms in children were not specific to the disease. Our findings also showed that the rate of asymptomatic infection in children was high and that it was difficult to recognize COVID-19 in children.

High prevalence of asymptomatic nosocomial candiduria due to Candida glabrata among hospitalized patients with heart failure: a matter of some concern?

Background and Purpose: Heart failure is a leading cause of hospitalization, and asymptomatic candiduria is common in hospitalized patients with low morbidity. However, in most patients, it is resolved spontaneously on the removal of the catheter. Despite the publication of guidelines, there are still controversies over the diagnosis and management of candiduria. However, in hospitalized patients with heart failure, the decision to treat candiduria is especially important since the nosocomial infections are associated with an increase in morbidity, mortality, length of hospital stay, and healthcare costs. Some species of Candida, such as Candida glabrata, are increasingly resistant to the first-line and second-line antifungal medications. The present study aimed to investigate the incidence of asymptomatic Candida urinary tract infection due to C. glabrata and antifungal susceptibility of Candida isolates in hospitalized patients with heart failure.Materials and Methods: In total, 305 hospitalized patients with heart failure were studied to identify asymptomatic nosocomial candiduria during 2016-17 in one private hospital in the north of Iran. The Sabouraud’s dextrose agar culture plates with a colony count of >104 colony-forming unit/ml of urine sample were considered as Candida urinary tract infection. Candida species were identified based on the morphology of CHROMagar Candida (manufactured by CHROMagar, France) and PCR-RFLP method with MspI restriction enzyme. Antifungal susceptibility testing of the isolates was performed using five mediations, including itraconazole, voriconazole, fluconazole, amphotericin B, and caspofungin by broth microdilution method according to CLSI M27-S4.Results: In this study, the rate of asymptomatic Candida urinary tract infection was 18.8%, which was more common in people above 51 years old and females (70%). In addition to the urinary and intravascular catheter, the occurrence of candiduria in hospitalized patients had significant relationships with a history of surgical intervention, diastolic heart failure, and use of systemic antibiotics (P>0.05). Among Candida spp., non-albicans Candida species was the most common infectious agent (59.7%). Moreover, C. glabrata (n=27, 40.3%) (alone or with other species) and Candida albicans (n=27, 40.3%) were the most common agents isolated in Candida urinary tract infection. Based on the results of the in vitro susceptibility test, the C. glabrata isolates were 15%, 59%, 70%, 74%, and 85% susceptible to caspofungin, amphotericin B, itraconazole, voriconazole, and fluconazole, respectively.Conclusion: According to the findings, there was a high prevalence of asymptomatic Candida urinary tract infection in hospitalized patients with heart failure. Besides, it was suggested that there was a shift towards non-albicans Candida, especially C. glabrata, in these patients. Therefore, asymptomatic candiduria in hospitalized patients with heart failure should be considered significant. Furthermore, the identification of Candida species along with antifungal susceptibility is essential and helps the clinicians to select the appropriate antifungal agent for better management of such cases.

Severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infection among hospital workers in a severely affected institution in Madrid, Spain: A surveillance cross-sectional study.

To analyze the impact of the coronavirus disease 2019 (COVID-19) pandemic in workers of a hospital located in one of the most affected areas in Spain. Cross-sectional study performed between March and May 2020 over all workers of a secondary hospital in Madrid, Spain. We employed polymerase chain reaction (PCR, for symptomatic individuals) and serology (for both PCR-negative symptomatic workers and asymptomatic workers) as diagnostic tests for severe acute respiratory coronavirus virus 2 (SARS-CoV-2). We analyzed the prevalence of the virus in healthcare workers (HCWs) and nonhealthcare workers (nHCWs). We also collected information about the use of personal protective equipment (PPEs) and possible contacts prior to infection. In total, 2,963 workers were included: 1,092 were symptomatic, and of these, 539 were positive by PCR (49.4% of symptomatic workers). From the remaining symptomatic workers, 197 (35.6%) were positive by serology. Regarding asymptomatic workers, 345 were positive by serology (31.9% of infected workers). In total, 1,081 (36.5%) presented a positive diagnostic test for SARS-CoV-2. Infection rates were different between HCWs (37.4%) and nHCWs (29.8%) (P = .006). In the multivariate logistic regression analysis, the use of PPE (protective: OR, 0.56; 95% CI, 0.44-0.72; P < .001) and previous contact with COVID-19 patients (risk factor: OR, 1.69; 95% CI, 1.28-2.24; P < .001) were independent factors that were associated with SAS-CoV-2 infection. Overall, >36% of our workers became infected with SARS-CoV-2, and the rate of asymptomatic infections accounted for almost 32% of all SARS-CoV-2 infections. We detected differences in the rates of infection between HCWs and nHCWs. The use of PPE and previous contact with COVID-19 patients were associated with SARS-CoV-2 infection.

Universal COVID-19 screening of 4040 health care workers in a resource-limited setting: an Egyptian pilot model in a university with 12 public hospitals and medical centers.

BackgroundThe scale of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among health care workers (HCWs), particularly in resource-limited settings, remains unclear. To address this concern, universal (non-symptom-based) screening of HCWs was piloted to determine the proportion of SARS-CoV-2 infection and the associated epidemiological and clinical risk factors at a large public health care facility in Egypt.MethodsBaseline voluntary screening of 4040 HCWs took place between 22 April and 14 May 2020 at 12 hospitals and medical centres in Cairo. Epidemiological and clinical data were collected using an online survey. All participants were tested for SARS-CoV-2 using reverse transcription polymerase chain reaction (RT-PCR) and rapid IgM and IgG serological tests.ResultsOf the 4040 HCWs screened, 170 [4.2%; 95% confidence interval (CI): 3.6-4.9] tested positive for SARS-CoV-2 by either of the three tests (i.e. infected); 125/170 (73.5%) tested PCR-positive. Most infected HCWs were nurses (97/170, 57.5%). Median age of infected HCWs was 31.5 [interquartile range (IQR): 27.0–41.3] years. Of infected HCWs, 78 (45.9%) reported contact with a suspected case and 47 (27.6%) reported face-to-face contact within 2 m with a confirmed case. The proportion of infection among symptomatic HCWs (n = 54/616) was 8.8% (95% CI: 6.7-11.3); 6/54 (11.1%) had fever ≥38°C and 7/54 (13.0%) reported severe symptoms. Most infected HCWs were asymptomatic (116/170, 68.2%). The proportion of infection among asymptomatic HCWs (n = 116/3424) was 3.4% (95% CI: 2.8-4.0).ConclusionsThe high rate of asymptomatic infections among HCWs reinforces the need for expanding universal regular testing. The infection rate among symptomatic HCWs in this study is comparable with the national rate detected through symptom-based testing. This suggests that infections among HCWs may reflect community rather than nosocomial transmission during the early phase of the COVID-19 epidemic in Egypt.

Coronavirus testing in women attending antenatal care

BackgroundUniversal screening has been proposed as a strategy to identify asymptomatic individuals infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and mitigate transmission. AimTo investigate the rate of positive tests among pregnant women in Melbourne, Australia. MethodsWe performed a cross-sectional prevalence study at three maternity hospitals (one tertiary referral hospital and two secondary maternities) in Melbourne, Australia. SARS-CoV-2 testing was offered to all pregnant women attending face-to-face antenatal visits and to those attending the hospital with symptoms of possible coronavirus disease, between 6th and 19th of May 2020. Testing was performed by multiplex-tandem polymerase chain reaction (PCR) on combined oropharyngeal and nasopharyngeal swabs. The primary outcome was the proportion of positive SARS-CoV-2 tests. FindingsSARS-CoV-2 testing was performed in 350 women, of whom 19 had symptoms of possible COVID-19. The median maternal age was 32 years (IQR 28–35 years), and the median gestational age at testing was 33 weeks and four days (IQR 28 weeks to 36 weeks and two days). All 350 tests returned negative results (p̂=0%, 95% CI 0–1.0%). ConclusionIn a two-week period of low disease prevalence, the rate of asymptomatic coronavirus infection among pregnant women in Australia during the study period was negligible, reflecting low levels of community transmission.

In-patient psychiatry management of COVID-19: rates of asymptomatic infection and on-unit transmission.

New York City's first case of SARS-associated coronavirus (SARS-CoV-2) disease 2019 (COVID-19) was identified on 1 March 2020, prompting rapid restructuring of hospital-based services to accommodate the increasing numbers of medical admissions. Non-essential services were eliminated but in-patient treatment of psychiatric illnesses was necessarily maintained. To detail the response of the NYU Langone Health in-patient psychiatric services to the COVID-19 outbreak from 1 March to 1 May 2020. Process improvement/quality improvement study. Over this time period, our two in-patient psychiatric units (57 total beds) treated 238 patients, including COVID-19-positive and -negative individuals. Testing for COVID-19 was initially limited to symptomatic patients but expanded over the 62-day time frame. In total, 122 SARS-CoV-2 polymerase chain reaction (PCR) tests were performed in 98 patients. We observed an overall rate of COVID-19 infection of 15.6% in the patients who were tested, with an asymptomatic positive rate of 13.7%. Although phased roll-out of testing impaired the ability to fully track on-unit transmission of COVID-19, 3% of cases were clearly identified as results of on-unit transmission. Our experience indicates that, with appropriate precautions, patients in need of in-patient psychiatric admission who have COVID-19 can be safely managed. We provide suggested guidelines for COVID-19 management on in-patient psychiatric units which incorporate our own experiences as well as published recommendations.

The Potential Role of Immune Alteration in the Cancer-COVID19 Equation-A Prospective Longitudinal Study.

Background: The risk of cancer patients to develop COVID19 infection is unclear. We aimed to prospectively study cancer patients and oncology healthcare workers for COVID19 serology. In IgG+ cases, immune profile was determined to portray the pattern of immune response to SARS-CoV2. Methods: Cancer patients on active treatment and healthcare workers were enrolled. During the study period (3/2020-6/2020), demographic data and blood were collected at three time points. Expression of IgG, IgM, and IgA were assessed. In SARS-CoV-2 IgG+ cases and matched negative cases, we performed mass cytometry time of flight (CyTOF) analysis on the basis of the expression of surface markers. Results: The study included 164 cancer patients on active intravenous treatment and 107 healthcare workers at the cancer center. No symptomatic cases were reported during the study period. Serology analysis revealed four IgG+ patients (2.4%) and two IgG+ healthcare workers (1.9%)-all were asymptomatic. CyTOF analysis demonstrated substantial reduction in myeloid cells in healthcare workers who were SARS-CoV-2 IgG+ compared to those who were SARS-CoV-2 IgG-, whereas in cancer patients, the reduction was relatively milder (≈50% reduction in SARS-CoV-2 IgG+ cancer patients compared with ≈90% reduction in SARS-CoV-2 IgG+ workers). Conclusion: Our results indicate a similar rate of asymptomatic COVID19 infection in cancer patients and healthcare workers in a longitudinal study throughout the pandemic time. Due to differential immune cell profiles of cancer patients who are treated with immunomodulatory agents, the host response to the SARS-COV2 may play a role in COVID19 course and representation. The immunological perspective of cancer treatments on the risk for COVID19 infection should be further explored.

Proportion of asymptomatic coronavirus disease 2019: A systematic review and meta-analysis.

We aim to systematically review the characteristics of asymptomatic infection in the coronavirus disease 2019 (COVID‐19). PubMed and EMBASE were electronically searched to identify original studies containing the rate of asymptomatic infection in COVID‐19 patients before 20 May 2020. Then mate‐analysis was conducted using R version 3.6.2. A total of 50 155 patients from 41 studies with confirmed COVID‐19 were included. The pooled percentage of asymptomatic infection is 15.6% (95% CI, 10.1%‐23.0%). Ten included studies contain the number of presymptomatic patients, who were asymptomatic at screening point and developed symptoms during follow‐up. The pooled percentage of presymptomatic infection among 180 initially asymptomatic patients is 48.9% (95% CI, 31.6%‐66.2%). The pooled proportion of asymptomatic infection among 1152 COVID‐19 children from 11 studies is 27.7% (95% CI, 16.4%‐42.7%), which is much higher than patients from all aged groups. Abnormal CT features are common in asymptomatic COVID‐19 infection. For 36 patients from 4 studies that CT results were available, 15 (41.7%) patients had bilateral involvement and 14 (38.9%) had unilateral involvement in CT results. Reduced white blood cell count, increased lactate dehydrogenase, and increased C‐reactive protein were also recorded. About 15.6% of confirmed COVID‐19 patients are asymptomatic. Nearly half of the patients with no symptoms at detection time will develop symptoms later. Children are likely to have a higher proportion of asymptomatic infection than adults. Asymptomatic COVID‐19 patients could have abnormal laboratory and radiational manifestations, which can be used as screening strategies to identify asymptomatic infection.

Asymptomatic infection by SARS-CoV-2 in healthcare workers: A study in a large teaching hospital in Wuhan, China

ObjectivesTo investigate the proportion and characteristics of asymptomatic infection among healthcare workers (HCWs). MethodsThis study retrospectively investigated 1407 HCWs who were screened for COVID-19 by chest computed tomography (CT) scans and nasopharyngeal swabs for SARS-CoV-2 nucleic acid. Demographics, CT features, nasopharyngeal swabs, baseline symptoms, and laboratory data were collected. ResultsOf 1407 HCWs, 235 had symptoms and 1172 were asymptomatic close contacts, of which, 107 were symptomatic cases and 84 were close contacts who had abnormal CT findings. Of 152 symptomatic individuals and 908 close contacts tested for SARS-CoV-2 nucleic acid, 122 symptomatic cases and 38 close contacts had positive reverse-transcriptase real-time polymerase chain (RT-PCR) test results. The rate of confirmed asymptomatic infections was 4.2% (38/908). Both symptomatic and asymptomatic infected cases had high titrations of specific IgG or had ≥four-fold increase in IgG during convalescence compared with the acute phase. Combining the RT-PCR tests and serological findings, the rate of asymptomatic infections was 9.7% (88/908). In terms of the duration of viral shedding, there was no significant difference between symptomatic mild/moderate participants and asymptomatic infections. ConclusionsThe findings demonstrated that a high rate of asymptomatic SARS-CoV-2 carriers existed among healthcare worker close contacts during the outbreak of COVID-19.