Antibody Test Results Research Articles

False reactive HIV rapid antibody test in pregnancy

Background: Universal screening of HIV infection in pregnant women is recommended by CDC as well as Indonesia Ministry of Health to prevent mother-to-child HIV transmission. Algorithm of HIV testing in pregnant women in Indonesia is similar to that in Integrated Counseling and Testing Centre (ICTC) which refes to WHO HIV Testing Strategy III. Pregnancy has been observed to be associated with false positive HIV testing that can cause serious emotional distress and unnecessary follow-up. Case Description: A 21 y old pregnant woman was referred to a tertiary hospital with premature rupture of the membranes. Before C-section, preoperative laboratory test panels were ordered, including for HIV to which she consented. A rapid HIV test (A1) was performed and tested reactive for antibodies against HIV. The second (A2) and third (A3) rapid tests were then performed and yielded non-reactive results, concluding the final result as negative. Reassessment of the patients showed no risk factors for HIV infection. This was the third case of reactive A1 with non-reactive A2 and A3 within the last year in the hospital. After confirmatory tests, which came back non-reactive and negative for fourth-generation HIV test and Western Blot, respectively, the A1 test was considered as false positive. Discussion: Based on several reports, there are alloantibodies in pregnancy, transfusions, transplantations, and autoimmune diseases that account for the increased false positive rate. Positive HIV antibody test results can occur in the absence of infection due to cross-reactivity between viral proteins and tested specimens, but such cross-reactivity is less common using current peptide-based EIAs which contain fewer antigens than previous viral lysate-based EIAs. However, clinicians should be aware that when HIV prevalence is low, as is often the case among pregnant women, a reactive EIA result is more likely to be false positive. Conclusion: Counselling and HIV test should be integrated in antenatal care. Diagnostic procedure of HIV test in pregnant women refers to WHO Testing Strategy III. Because the positive predictive value of HIV test in obstetric population is low, positive screening results should be handled carefully and appropriate confirmatory testing should always be pursued.

Study on the effect of direct anti-human globulin test positive strength on patients' red blood cell transfusion

Objective: To investigate the effect of direct antiglobulin test (DAT) positive strength on the clinical effect of red blood cell transfusion. Methods: The clinical data was collected on blood transfusion compatibility test and clinical transfusion of patients who underwent DAT testing from January 2015 to March 2019 in the Department of Blood Transfusion, Beijing Shijitan Hospital affiliated to Capital Medical University. A retrospective cohort study method was used to analyze the correlation between the DAT positive strength and the blood match results, irregular antibody test results, bilirubin value after blood transfusion, and red blood cell transfusion effect. Results: According to the blood matching test results, the minor cross-matching results were significantly correlated with the DAT strength (r=0.58, P<0.01). The DAT strength of the antibody-screening positive patients was greater (χ(2)=126.810, P<0.01). DAT-positive strength influences the direct bilirubin, the higher the DAT-positive strength, the higher the direct bilirubin concentration of the patients (χ(2)=32.069, P<0.01). DAT-positive strength also had an effect on patients' total bilirubin value (χ(2)=17.981, P=0.001). From the effect of red blood cell transfusion, patients with a DAT positive strength of 0.5 had a lower effective rate of transfusion (28.6%). The remaining DAT strength had no relation to the effect of red blood cell transfusion, and the efficiency of blood transfusion in patients with different DAT-positive strengths (1, 2, 3, 4) was 57.0%, 60.1%, 65.6% and 60.0%, respectively. With the same DAT strength, the patient's transfusion efficiency was higher (χ(2)=41.071, P=0.009). Conclusion: Different DAT-positive strengths are correlated with the patient's minor cross-match results and bilirubin content, while the effect of red blood cell transfusion has no significant correlation with DAT-positive strength. However, with the increase of DAT positive strength, patients are more likely to have irregular antibodies.

HIV antibody screening and ways to improve it to address the problem of containing the spread of HIV infection

The purpose of the study is to determine the current trends in the development of the HIV epidemic process for individual subjects of the Ural Federal district (UFD) and the possibility of corrective measures to update the practice based on the results of screening tests for HIV antibodies.Materials and methods. The study used information from form 4 of the Federal statistical observation «Information on the results of blood tests for HIV antibodies» in the amount of 26,1 million studies for 2009–2018, information from 2,488 questionnaires from two biopsychological studies among commercial sex workers (CSR) and persons in prison. Research result. It was found that, despite the increase in the incidence of HIV infection in the period 2009–2018, the estimated Hurst indicator for the studied time period characterized the long-term dynamics of the incidence as antipersistent. Among MSM and patients with STIs, there is a marked tendency to increase the detection of HIV infection. Among commercial sex workers (CSR) and people in prison, the results of a sentinel bio-behavioral study found high detection of HIV antibodies against the background of risky sexual behavior.According to the indicators of the frequency of detection of antibodies to HIV in screening studies, the territories of the greatest potential risk of HIV infection were determined. In dynamics, there was an increase in the number of studies and the detection of HIV infection among those examined for clinical and epidemic indications (codes 113, 120) and stabilization of the detection of HIV infection among injecting drug users (code 102).Conclusion. In the period 2016–2018, the sexual route of infection became predominant among HIV-infected people. The greatest intensity of HIV infection was observed among such categories of the population covered by official statistics and who are representatives of groups with a predominant HIV infection, such as MSM and patients with STIs. At the same time, there was a decrease in HIV surveys among these populations with an increase in detection.The results of behavioral studies among DCS and persons in prison demonstrate high detection of HIV antibodies among them, as well as the presence of risky sexual behavior. Screening for HIV infection requires additional optimization.

Routine Screening and Linkage to Care for Hepatitis C Virus in an Urban Safety-Net Health System, 2017-2019.

Hepatitis C virus (HCV) is a major threat to public health in the United States. We describe and evaluate an HCV screening and linkage-to-care program, including emergency department, inpatient, and outpatient settings, in an urban safety-net health system in Chicago. Sinai Health System implemented a universal HCV screening program in September 2016 that offered patient navigation services (ie, linkage to care) to patients with a positive result for HCV on an RNA test. We collected data from February 1, 2017, through January 31, 2019, on patient demographic characteristics, risk factors, and various outcomes (eg, number of patients screened, test results, proportions of new diagnoses, number of patients eligible for patient navigation services, and proportion of patients who attended their first medical appointment). We also examined outcomes by patients' knowledge of infection. Of 21 018 people screened for HCV, 6% (1318/21 018) had positive test results for HCV antibody, 68% (878/1293) of whom had positive HCV RNA test results. Of these 878 patients, 68% were born during 1945-1965, 68% were male, 65% were Black, 19% were Latino, 55% were newly diagnosed, and 64% were eligible for patient navigation services. Risk factors included past or current drug use (53%), unemployment (30%), and ever incarcerated (21%). Of 562 patients eligible for navigation services, 281 (50%) were navigated to imaging services, and 203 (72%) patients who completed imaging attended their first medical appointment. Patient navigation played a critical role in linkage success, but securing stable, long-term financial support for patient navigators is a challenge.

The first results of laboratory tests for antibodies to SARS-CoV-2 of the medical personnel of the Mezhdurechensk city hospital

The emergence of a new coronavirus infection COVID-19 has led to an enormous burden on the health service and an increase in the risk of infection of medical workers with the SARS-CoV-2 virus. Purpose of the study. To study the level of humoral immunity to SARS-CoV-2 in hospital medical personnel. Materials and methods . For August-September 2020. 368 studies were carried out for the qualitative determination of IgM and IgG to SARS-CoV-2. 254 hospital employees were examined: 54 doctors (21,3%), 193 nurses (76%), 7 nurses (2,7%). Results . It was found that among doctors and nurses there is approximately the same proportion of people with an immune response to the previous SARS-CoV-2 infection – 16,7% and 18,1%, respectively. The largest number of newly diagnosed patients from among those surveyed – among the nursing staff of therapeutic departments. Conclusion. Out of 254 medical workers examined in August-September 2020 in the hospital laboratory, 45 people (17,7%) have antibodies to SARS-CoV-2. It is necessary to continue testing employees with a broad involvement of the outpatient service and other departments and contingents of personnel.

Screening for SARS-CoV-2: Health Policy Implications in Low- and Middle-Income Countries

Screening for SARS-CoV-2: Health Policy Implications in Low- and Middle-Income Countries

Nucleic acid and antibody assay results in Chinese patients with coronavirus disease 2019 (COVID-19)

AimTo evaluate the nucleic acid and antibody test results of patients with Coronavirus Disease 2019 (COVID-19) in China. MethodsAll patients with laboratory-confirmed SARS-CoV-2 infection from Jan to Apr 2020were retrospectively analyzed. Clinical characteristics and laboratory test results were obtained from electronic medical records. Patients were divided into three groups based on antibody production, and compared for laboratory test results. ResultsOf 73 patients aged11–82 years, 12 (16.4%), 28 (38.4%), 25 (34.2%) and 8 (11.0%)were ≤ 30, 31–50, 51–70,and ≥ 71 years old, respectively. Thirty-four (46.6%) patients were male. Most individuals had mild symptoms, and no patient died during treatment. All patients were tested positive for SARS-CoV-2 in sputum and nasopharyngeal samples, and 40 (54.8%) were also tested positive in stool. Nine(12.3%) patients were re-positivefor SARS-CoV-2, as assessed by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) after discharge. Sixty-five (89.0%) patients had IgM or IgG antibodies against SARS-CoV-2.Among the four age groups, there was no difference in IgG antibody production (P = 0.664).CD3, CD4, CD8 and CD19 cell counts between the antibody producing and non-producing groups showed no significant differences (all P > 0.05).The antibodies disappeared within two months in four patients. Lymphocyte count, C-reactive protein, IL-6, lactate dehydrogenase, alanine aminotransferase, creatinine and D-Dimer levels were similar in the three groups (all P > 0.05). ConclusionsPatients after recovery from COVID-19 can be tested positive for SARS-CoV-2.Some patients may produce antibodies only for a short time, or even no antibodies at all.

Study Protocol: Understanding SARS-Cov-2 infection, immunity and its duration in care home residents and staff in England (VIVALDI)

Global infection and mortality rates from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are disproportionately high in certain populations, including the elderly. Care home residents are frequently exposed to infection due to contact with staff and other residents, and are highly susceptible to infection due to their age and co-morbidity. In England, official statistics suggest that at least 25% of all deaths in care home residents since the start of pandemic are linked to coronavirus disease 2019 (COVID-19), but limited testing for SARS-CoV-2 early in the pandemic means estimates of the true burden of disease are lacking. Additionally, little is known about patterns of transmission between care homes, the community and hospitals, or the relationship between infection and immunity in care home staff and residents. The VIVALDI study plans to address these questions. VIVALDI is a prospective cohort study aiming to recruit 6,500 staff and 5000 residents from 105 care homes across England. Successive rounds of testing for infection will be performed over a period of 12 months. Nasopharyngeal swabs will detect evidence of viral RNA and therefore active infection (accompanied by collection of data on symptoms), whereas blood tests will detect antibodies and evidence of cellular immunity to SARS-CoV-2. Whole genome sequencing of viral isolates to investigate pathways of transmission of infection is planned in collaboration with the COVID-19 Genomics UK Consortium. Qualitative interviews with care home staff will investigate the impact of the pandemic on ways of working and how test results influence infection control practices and behaviours. Data from residents and staff will be linked to national datasets on hospital admissions, antibody and PCR test results, mortality and care home characteristics. Data generated will support national public health efforts to prevent transmission of COVID-19 and protect care home staff and residents from infection. Protocol registration: ISRCTN14447421 05/06/2020

Clinical outcomes of pediatric Anti-NMDA receptor encephalitis.

To investigate the clinical features and long-term outcomes of pediatric Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. Thirty-two anti-NMDAR encephalitis patients with positive anti-NMDAR antibody test results were recruited. Clinical outcomes were evaluated using the Clinical Assessment Scale in Autoimmune Encephalitis (CASE) and the modified Rankin Scale (mRS). The median age of onset was 9.0 years (range, 0.7-17.2 years). Twenty-four patients (75.0%) were female. All patients received first-line immunotherapy including intravenous immunoglobulin and/or steroid therapy. The second-line immunotherapy was administered to 22 patients (68.8%). Clinical outcomes were evaluated in 27 patients who were followed for longer than 6 months after onset, among whom the median follow-up duration was 31.2 months (range, 6.3-82.9 months). The proportion of patients with ≤2 points on the mRS at their 12-month follow-up was 79.2% (19/24). The CASE scores of these 19 patients ranged from 0 to 5, with language and memory deficits accounting for most of these disabilities. When the outcome was assessed according to onset age (<12 years or 12-18 years), the younger group tended to show a slower recovery over their clinical course. Despite overall favorable clinical outcomes, mild cognitive problems, including language and memory, may persist in pediatric anti-NMDAR encephalitis patients. A specific outcome measure, such as CASE, should be adopted to delineate clinical outcomes and aid the development of individualized treatment plans.

Clinical Ordering Practices of the SARS-CoV-2 Antibody Test at a Large Academic Medical Center.

BackgroundThe novel severe acute respiratory coronavirus 2 (SARS-CoV-2) that causes coronavirus disease 2019 (COVID-19) originated in December 2019 and has now infected almost 5 million people in the United States. In the spring of 2020, private laboratories and some hospitals began antibody testing despite limited evidence-based guidance.MethodsWe conducted a retrospective chart review of patients who received SARS-CoV-2 antibody testing from May 14, 2020, to June 15, 2020, at a large academic medical center, 1 of the first in the United States to provide antibody testing capability to individual clinicians in order to identify clinician-described indications for antibody testing compared with current expert-based guidance from the Infectious Diseases Society of America (IDSA) and the Centers for Disease Control and Prevention (CDC).ResultsOf 444 individual antibody test results, the 2 most commonly described testing indications, apart from public health epidemiology studies (n = 223), were for patients with a now resolved COVID-19-compatible illness (n = 105) with no previous molecular testing and for asymptomatic patients believed to have had a past exposure to a person with COVID-19-compatible illness (n = 60). The rate of positive SARS-CoV-2 antibody testing among those indications consistent with current IDSA and CDC guidance was 17% compared with 5% (P < .0001) among those indications inconsistent with such guidance. Testing inconsistent with current expert-based guidance accounted for almost half of testing costs.ConclusionsOur findings demonstrate a dissociation between clinician-described indications for testing and expert-based guidance and a significantly different rate of positive testing between these 2 groups. Clinical curiosity and patient preference appear to have played a significant role in testing decisions and substantially contributed to testing costs.

HEPCARE EUROPE- A case study of a service innovation project aiming at improving the elimination of HCV in vulnerable populations in four European cities

ObjectivesHepatitis C Virus (HCV) is a significant cause of chronic liver disease. Among at-risk populations, access to diagnosis and treatment is challenging. We describe an integrated model of care, Hepcare Europe, developed to address this challenge. MethodsUsing a case-study approach, we describe the cascade of care outcomes at all sites. Cost analyses estimated the cost per person screened and linked to care. ResultsA total of 2608 participants were recruited across 218 clinical sites. HCV antibody test results were obtained for 2568(98•5%); 1074(41•8%) were antibody-positive, 687(60•5%) tested positive for HCV-RNA, 650(60•5%) were linked to care, and 319(43•5%) started treatment. 196(61•4%) of treatment initiates achieved a Sustained Viral Response (SVR) at dataset closure, 108(33•9%) were still on treatment, eight (2•7%) defaulted from treatment, and seven (2•6%) had virologic failure or died. The cost per person screened varied from €194 to €635, while the cost per person linked to care varied from €364 to €2035. ConclusionsHepcare enhanced access to HCV treatment and cure, and costs were affordable in all settings, offering a framework for scale-up and reproducibility.

Concurrent minimal change nephrotic syndrome and type 1 diabetes mellitus in an adult Japanese woman: a case report

BackgroundConcurrent type 1 diabetes mellitus (T1DM) and idiopathic nephrotic syndrome is rare, and most previously reported cases were in children. We report the case of an adult woman who developed T1DM and minimal change nephrotic syndrome (MCNS) nearly simultaneously.Case presentationA 24-year-old woman had first presented to another hospital with nausea, vomiting, and fatigue. She was diagnosed with diabetic ketoacidosis and T1DM on the basis of her hyperglycemia, ketoacidosis, and positive anti-glutamic acid decarboxylase antibody test result. Rapid infusion of normal saline and insulin administration alleviated hyperglycemia and ketoacidosis. Two weeks after admission, however, she developed nephrotic syndrome (NS) with rapidly decreasing urine volume. She was referred to our hospital with a diagnosis of acute kidney injury. Although she temporarily required dialysis and high doses of insulin, within 1 month NS and acute kidney injury had been alleviated by oral prednisolone and low-density lipoprotein apheresis. Renal biopsy showed minor glomerular abnormalities without diabetic nephropathy, so we diagnosed her with MCNS. Seven weeks after the discharge, NS relapsed, and cyclosporine was added to prednisolone. However, NS relapsed twice within the next 4 months, so we started her on rituximab. At 6 months after initiating rituximab therapy, she remained in complete remission.Her mother also had T1DM but not MCNS. The patient had HLA-DRB1*09:01/09:01, DQB1*03:03/03:03, and her mother had HLA-DRB1*04:05/09:01, DQB1*03:03/04:01.ConclusionsConcurrent T1DM and MCNS is rare and their coexistence might be coincidental. Alternatively, they might have been caused by an underlying, unidentified genetic predisposition. Previous reports and our patient’s findings suggest that specific HLA alleles and haplotypes or a Th1/Th2 imbalance might be associated with T1DM and MCNS that occurred nearly simultaneously.

Pruebas rápidas de anticuerpos contra el SARS-CoV-2: reporte de una experiencia en un Servicio de Emergencia

Objetivo: Determinar la positividad y los patrones de los resultados positivos de las pruebas rápidas de anticuerpos contra el SARS-CoV-2 en los pacientes atendidos en un Servicio de Emergencia. Materiales y métodos: Evaluación retrospectiva de las pruebas rápidas de anticuerpos contra el SARS-CoV-2 aplicadas durante el mes de junio/2020 en el Servicio de Emergencia del Hospital EsSalud G. Almenara, Lima, Perú. Resultados: Fueron evaluadas 1 805 pruebas realizadas en igual número de pacientes. En 864 (48%) de las pruebas fueron positivas, en el siguiente orden: patrón combinado de IgM-IgG en 635 (73%), IgM en 134 (16%) y, finalmente, de IgG en 95 (11%). Conclusiones: La positividad de las pruebas rápidas de anticuerpos contra el SARS-CoV-2 fue de 48%, y el patrón combinado de IgM-IgG fue el más frecuente, en tres cuartas partes de los casos confirmados.

Timing of PCR and antibody testing in patients with COVID-19–associated dermatologic manifestations

Timing of PCR and antibody testing in patients with COVID-19–associated dermatologic manifestations

Diagnosis and Treatment of 43 Patients with IgG4-related Disease

To summarize the clinicopathological characteristics, diagnosis and treatment of IgG4-related disease (IgG4-RD). The clinical data of 43 cases with IgG4-RD diagnosed from January 2013 to December 2017 were retrospectively analyzed. The clinical data of the patients including clinical characteristics, accessory examinations, diagnosis, and treatment were collected. Among the 43 patients with IgG4-RD, the ratio of male to female was 3∶1, the mean age was (51.3±15.9) years. Eleven patients had gastrointestinal symptoms, including 5 cases of IgG4-related cholangitis with the feature of dilation of the biliary system and narrowing of the lumen in the abdominal enhanced CT scans, and 6 cases of IgG4-related autoimmune pancreatitis with the feature of pancreatic enlargement or soft tissue density shadow in the abdominal enhanced CT scans. There were 10 cases (23.3%) with periorbital involvement, with the feature of intraorbital soft tissue nodule in the CT scan. Besides, 9 cases (20.9%) had lymphadenopathy, 6 cases (14.0%) had fever. The results of autoimmune antibody tests showed that 14 of 42 patients had increased antinuclear antibody (ANA). Among 40 patients who underwent immunoglobulin tests, 25 cases had elevated IgG, 12 cases had increased IgA, and 29 cases had increased IgE. Coombs test were performed for 6 cases and 4 patients were positive. Serum immunoglobulin G4 subtypes showed that the IgG4 levels of 35 patients were higher than 1 350 mg/L. The immunohistochemistry showed that IgG4 (+) cells (3->500/HPF) were infiltrated, with the CD20 (+), CD3ε (+) or CD138 (+). Among the 43 patients, 5 patients underwent operations due to misdiagnosis. All patients were treated with steroid and immunosuppressive agents after diagnosis, and their clinical symptoms were improved. The clinical symptoms of IgG4-RD are various, involving multiple organs. Therefore, the standardized diagnosis and treatment of IgG4-RD should be strengthened.

Observational study of SARS-CoV-2 antibody immune response in a cohort of patients at a North Suburban Chicago, Illinois, in a physician’s practice

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic. The application of point of care serological testing can help determine past infection and assist healthcare workers assess patient risk. Method: An observational study of 114 subjects in North Suburban Chicago, Illinois, was performed using the Clungene® lateral flow immunoassay (LFI). Patients’ PCR test results and clinical symptoms were used to compare the seroconversion rate of this patient population with the surrounding community. Results: Excluding 1 aberrant result, there was 100% positive agreement (10) between PCR and antibody (IgG or IgM) test results. There were 7 patients who did not have a prior PCR test who were positive for IgG; 5 of the 7 had clinical symptoms consistent with possible exposure and 2 were asymptomatic. There was 1 person with a suspected exposure to an infected person who was IgM positive. Ninety-five asymptomatic patients were seronegative. The overall rate of 15.9% seroconversion (IgG or IgM) is consistent with other community-based testing results in the North Suburban Chicago, Illinois area. Conclusion: Rapid screening tests to identify antibody positive patients recovered from coronavirus disease-2019 can be a useful tool for healthcare professionals to determine or confirm past infection. Statement of novelty: Limited data is available on the use of point of care serological testing to assist healthcare professionals with the assessment of their patient population regarding past SARS-CoV-2 infectivity and seroconversion. The present study successfully investigated the use of a point of care antibody test in a physician’s office to determine which patients have developed antibodies, indicating an immune response to SARS-CoV-2, and to assist with decisions on whether patients should pursue normal social and workplace activities.

New-onset graves\u2019 disease after the initiation of nivolumab therapy for gastric cancer: a case report

BackgroundImmune checkpoint inhibitors (ICIs) can induce immune-related adverse events (irAEs) including thyroid dysfunction. There are only a few reports on Graves’ disease induced by ICIs. We report a case of new-onset Graves’ disease after the initiation of nivolumab therapy in a patient receiving gastric cancer treatment.Case presentationThe patient was a 66-year-old Japanese man, who was administered nivolumab (240 mg every 3 weeks) as a third-line therapy for stage IVb gastric cancer. His thyroid function was normal before the initiation of nivolumab therapy. However, he developed thyrotoxicosis before the third administration of nivolumab. Elevated, bilateral, and diffuse uptake of radioactive tracer was observed in the 99mTc-pertechnetate scintigraphy. Furthermore, the thyroid-stimulating hormone receptor antibody (TRAb) and thyroid-stimulating antibody (TSAb) test results, which were negative before the first administration of nivolumab, were positive after starting the therapy. The patient was diagnosed with Graves’ disease, and the treatment with methimazole and potassium iodide restored thyroid function.ConclusionsThis is the first complete report of a case of new-onset Graves’ disease after starting nivolumab therapy, confirmed by diffusely increased thyroid uptake in scintigraphy and the positive conversion of antibodies against thyroid-stimulating hormone receptor. It is important to perform thyroid scintigraphy and ultrasonography to accurately diagnose and treat ICI-induced thyrotoxicosis, because there are various cases in which Graves’ disease is developed with negative and positive TRAb titres.

Protocol for a national probability survey using home specimen collection methods to assess prevalence and incidence of SARS-CoV-2 infection and antibody response

PurposeThe U.S. response to the SARS-CoV-2 epidemic has been hampered by early and ongoing delays in testing for infection; without data on where infections were occurring and the magnitude of the epidemic, early public health responses were not data-driven. Understanding the prevalence of SARS-CoV-2 infections and immune response is critical to developing and implementing effective public health responses. Most serological surveys have been limited to localities that opted to conduct them and/or were based on convenience samples. Moreover, results of antibody testing might be subject to high false positive rates in the setting of low prevalence of immune response and imperfect test specificity. MethodsWe will conduct a national serosurvey for SARS-CoV-2 PCR positivity and immune experience. A probability sample of U.S. addresses will be mailed invitations and kits for the self-collection of anterior nares swab and finger prick dried blood spot specimens. Within each sampled household, one adult 18 years or older will be randomly selected and asked to complete a questionnaire and to collect and return biological specimens to a central laboratory. Nasal swab specimens will be tested for SARS-CoV-2 RNA by RNA PCR; dried blood spot specimens will be tested for antibodies to SARS-CoV-2 (i.e., immune experience) by enzyme-linked immunoassays. Positive screening tests for antibodies will be confirmed by a second antibody test with different antigenic basis to improve predictive value of positive (PPV) antibody test results. All persons returning specimens in the baseline phase will be enrolled into a follow-up cohort and mailed additional specimen collection kits 3 months after baseline. A subset of 10% of selected households will be invited to participate in full household testing, with tests offered for all household members aged ≥3 years. The main study outcomes will be period prevalence of infection with SARS-CoV-2 and immune experience, and incidence of SARS-CoV-2 infection and antibody responses. ResultsPower calculations indicate that a national sample of 4000 households will facilitate estimation of national SARS-CoV-2 infection and antibody prevalence with acceptably narrow 95% confidence intervals across several possible scenarios of prevalence levels. Oversampling in up to seven populous states will allow for prevalence estimation among subpopulations. Our 2-stage algorithm for antibody testing produces acceptable PPV at prevalence levels ≥1.0%. Including oversamples in states, we expect to receive data from as many as 9156 participants in 7495 U.S. households. ConclusionsIn addition to providing robust estimates of prevalence of SARS-CoV-2 infection and immune experience, we anticipate this study will establish a replicable methodology for home-based SARS-CoV-2 testing surveys, address concerns about selection bias, and improve positive predictive value of serology results. Prevalence estimates of SARS-CoV-2 infection and immune experience produced by this study will greatly improve our understanding of the spectrum of COVID-19 disease, its current penetration in various demographic, geographic, and occupational groups, and inform the range of symptoms associated with infection. These data will inform resource needs for control of the ongoing epidemic and facilitate data-driven decisions for epidemic mitigation strategies.

Value of Viral Nucleic Acid in Sputum and Feces and Specific IgM/IgG in Serum for the Diagnosis of Coronavirus Disease 2019.

A new type of coronavirus-induced pneumonia eventually termed “coronavirus disease 2019” (COVID-19) was diagnosed in patients in Wuhan (Hubei Province, China) in December 2019, and soon spread worldwide. To improve the detection rate of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), we analyzed the results of viral nucleic acid and serum-specific antibody tests on clinical samples from 20 patients with SARS-CoV-2 infection diagnosed at the First Affiliated Hospital of Guangzhou Medical University in China. By comparing various sample types collected from COVID-19 patients, we revealed multiple pathways for SARS-CoV-2 shedding, and a prolonged detectable period for viral nucleic acid test in sputum specimens, demonstrating that the timeline of the viral shedding is of great value in determining the time of release from quarantine or discharge from hospital. We also recommend for the application of serological test to assist in confirming SARS-CoV-2 infection judged by viral nucleic acid test, especially when COVID-19-related symptoms have appeared and the viral nucleic acid test was negative. Our findings are critical for the diagnosis of SARS-CoV-2 infection and for determining deadline of restriction measures to prevent transmission caused by convalescent patients with COVID-19.

Air and surface contamination by SARS-CoV-2 virus in a tertiary hospital in Wuhan, China

BackgroundFew studies have explored air and surface contamination by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in healthcare settings. MethodsAir and surface samples were collected from the isolation wards and intensive care units designated for coronavirus disease 2019 (COVID-19) patients. Clinical data and the results of nasopharyngeal specimen and serum antibody testing were also collected for the patient sample. ResultsA total of 367 air and surface swab samples were collected from the patient care areas of 15 patients with mild COVID-19 and nine patients with severe/critical COVID-19. Only one air sample taken during the intubation procedure tested positive. High-touch surfaces were slightly more likely to be contaminated with SARS-CoV-2 RNA than low-touch surfaces. Contamination rates were slightly higher near severe/critical patients than near mild patients, although this difference was not statistically significant (p > 0.05). Surface contamination was still found near the patients with both positive IgG and IgM. ConclusionsAir and surface contamination with viral RNA was relatively low in these healthcare settings after the enhancement of infection prevention and control. Environmental contamination could still be found near seroconverted patients, suggesting the need to maintain constant vigilance in healthcare settings to reduce healthcare-associated infection during the COVID-19 pandemic.