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1.
Am J Prev Med ; 61(3): 369-376, 2021 09.
Article in English | MEDLINE | ID: covidwho-1258300

ABSTRACT

INTRODUCTION: The COVID-19 pandemic has disrupted healthcare services, reducing opportunities to conduct routine hepatitis C virus antibody screening, clinical care, and treatment. Therefore, people living with undiagnosed hepatitis C virus during the pandemic may later become identified at more advanced stages of the disease, leading to higher morbidity and mortality rates. Further, unidentified hepatitis C virus-infected individuals may continue to unknowingly transmit the virus to others. METHODS: To assess the impact of the COVID-19 pandemic, data were evaluated from a large national reference clinical laboratory and from national estimates of dispensed prescriptions for hepatitis C virus treatment. Investigators estimated the average number of hepatitis C virus antibody tests, hepatitis C virus antibody-positive test results, and hepatitis C virus RNA-positive test results by month in January-July for 2018 and 2019, compared with the same months in 2020. To assess the impact of hepatitis C virus treatment, dispensed hepatitis C virus direct-acting antiretroviral medications were examined for the same time periods. Statistical analyses of trends were performed using negative binomial models. RESULTS: Compared with the 2018 and 2019 months, hepatitis C virus antibody testing volume decreased 59% during April 2020 and rebounded to a 6% reduction in July 2020. The number of hepatitis C virus RNA-positive results fell by 62% in March 2020 and remained 39% below the baseline by July 2020. For hepatitis C virus treatment, prescriptions decreased 43% in May, 37% in June, and 38% in July relative to the corresponding months in 2018 and 2019. CONCLUSIONS: During the COVID-19 pandemic, continued public health messaging, interventions and outreach programs to restore hepatitis C virus testing and treatment to prepandemic levels, and maintenance of public health efforts to eliminate hepatitis C infections remain important.


Subject(s)
COVID-19 , Hepatitis C , Hepacivirus , Hepatitis C/diagnosis , Hepatitis C/drug therapy , Hepatitis C/epidemiology , Humans , Pandemics , SARS-CoV-2
2.
Popul Health Manag ; 24(S1): S35-S42, 2021 02.
Article in English | MEDLINE | ID: covidwho-1236196

ABSTRACT

Serologic tests for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) provide information on past infection and immune response. To better understand the persistence of immune response and the proportion of the population who can develop one, the authors assessed patterns of immunoglobulin G (IgG) positivity over time in individuals tested for SARS-CoV-2 RNA or IgG at a large national reference laboratory. More than 2.4 million SARS-CoV-2 IgG serology (initiated April 21, 2020) and 6.6 million nucleic acid amplification testing (NAAT) (initiated March 9, 2020) results on persons from across the United States as of July 10, 2020 were analyzed. Additional IgG serology results through August 11, 2020 were used for one household analysis. SARS-CoV-2 IgG positivity was observed in 91% (19,434/21,452) of individuals tested after a positive NAAT result and in 10% (7,831/80,968) after a negative NAAT result. Factors associated with seropositivity include age, region of patient residence, and interval between NAAT and IgG serology. The probability of persistent IgG seropositivity declined from 98.6% after 1 week to 74.3% after 2 months, less so in individuals ages ≥55 years than in younger groups. Specimens within 2 days from pairs of same-household members showed 92% IgG antibody concordance. Household adults were more frequently IgG positive prior to household children testing positive (36% versus 8%). IgG serology testing can identify an immune response to SARS-CoV-2 that varies based on age, sex, and duration since exposure. Loss of detectable IgG seropositivity occurs, in some patients, over weeks or months. Adults may be infecting household children.


Subject(s)
Antibodies, Viral/blood , COVID-19 , Immunoglobulin G/blood , SARS-CoV-2 , Adolescent , Adult , COVID-19/epidemiology , COVID-19/immunology , COVID-19/virology , Child , Child, Preschool , Female , Humans , Laboratories , Male , Middle Aged , Nucleic Acid Amplification Techniques , Retrospective Studies , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Serologic Tests , United States , Young Adult
3.
JAMA Intern Med ; 181(5): 672-679, 2021 05 01.
Article in English | MEDLINE | ID: covidwho-1098863

ABSTRACT

Importance: Understanding the effect of serum antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on susceptibility to infection is important for identifying at-risk populations and could have implications for vaccine deployment. Objective: The study purpose was to evaluate evidence of SARS-CoV-2 infection based on diagnostic nucleic acid amplification test (NAAT) among patients with positive vs negative test results for antibodies in an observational descriptive cohort study of clinical laboratory and linked claims data. Design, Setting, and Participants: The study created cohorts from a deidentified data set composed of commercial laboratory tests, medical and pharmacy claims, electronic health records, and hospital chargemaster data. Patients were categorized as antibody-positive or antibody-negative according to their first SARS-CoV-2 antibody test in the database. Main Outcomes and Measures: Primary end points were post-index diagnostic NAAT results, with infection defined as a positive diagnostic test post-index, measured in 30-day intervals (0-30, 31-60, 61-90, >90 days). Additional measures included demographic, geographic, and clinical characteristics at the time of the index antibody test, including recorded signs and symptoms or prior evidence of coronavirus 2019 (COVID) diagnoses or positive NAAT results and recorded comorbidities. Results: The cohort included 3 257 478 unique patients with an index antibody test; 56% were female with a median (SD) age of 48 (20) years. Of these, 2 876 773 (88.3%) had a negative index antibody result, and 378 606 (11.6%) had a positive index antibody result. Patients with a negative antibody test result were older than those with a positive result (mean age 48 vs 44 years). Of index-positive patients, 18.4% converted to seronegative over the follow-up period. During the follow-up periods, the ratio (95% CI) of positive NAAT results among individuals who had a positive antibody test at index vs those with a negative antibody test at index was 2.85 (95% CI, 2.73-2.97) at 0 to 30 days, 0.67 (95% CI, 0.6-0.74) at 31 to 60 days, 0.29 (95% CI, 0.24-0.35) at 61 to 90 days, and 0.10 (95% CI, 0.05-0.19) at more than 90 days. Conclusions and Relevance: In this cohort study, patients with positive antibody test results were initially more likely to have positive NAAT results, consistent with prolonged RNA shedding, but became markedly less likely to have positive NAAT results over time, suggesting that seropositivity is associated with protection from infection. The duration of protection is unknown, and protection may wane over time.


Subject(s)
COVID-19 Nucleic Acid Testing , COVID-19 Serological Testing , COVID-19 , Disease Susceptibility , SARS-CoV-2 , Adult , Age Factors , Antibodies, Viral/isolation & purification , COVID-19/blood , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Nucleic Acid Testing/methods , COVID-19 Nucleic Acid Testing/statistics & numerical data , COVID-19 Serological Testing/methods , COVID-19 Serological Testing/statistics & numerical data , Correlation of Data , Disease Susceptibility/diagnosis , Disease Susceptibility/epidemiology , Disease Susceptibility/immunology , Female , Humans , Male , Middle Aged , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Seroepidemiologic Studies , Symptom Assessment/methods , Symptom Assessment/statistics & numerical data , United States/epidemiology , Virus Shedding/immunology
4.
JAMA Intern Med ; 181(4): 450-460, 2021 04 01.
Article in English | MEDLINE | ID: covidwho-965464

ABSTRACT

Importance: Case-based surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection likely underestimates the true prevalence of infections. Large-scale seroprevalence surveys can better estimate infection across many geographic regions. Objective: To estimate the prevalence of persons with SARS-CoV-2 antibodies using residual sera from commercial laboratories across the US and assess changes over time. Design, Setting, and Participants: This repeated, cross-sectional study conducted across all 50 states, the District of Columbia, and Puerto Rico used a convenience sample of residual serum specimens provided by persons of all ages that were originally submitted for routine screening or clinical management from 2 private clinical commercial laboratories. Samples were obtained during 4 collection periods: July 27 to August 13, August 10 to August 27, August 24 to September 10, and September 7 to September 24, 2020. Exposures: Infection with SARS-CoV-2. Main Outcomes and Measures: The proportion of persons previously infected with SARS-CoV-2 as measured by the presence of antibodies to SARS-CoV-2 by 1 of 3 chemiluminescent immunoassays. Iterative poststratification was used to adjust seroprevalence estimates to the demographic profile and urbanicity of each jurisdiction. Seroprevalence was estimated by jurisdiction, sex, age group (0-17, 18-49, 50-64, and ≥65 years), and metropolitan/nonmetropolitan status. Results: Of 177 919 serum samples tested, 103 771 (58.3%) were from women, 26 716 (15.0%) from persons 17 years or younger, 47 513 (26.7%) from persons 65 years or older, and 26 290 (14.8%) from individuals living in nonmetropolitan areas. Jurisdiction-level seroprevalence over 4 collection periods ranged from less than 1% to 23%. In 42 of 49 jurisdictions with sufficient samples to estimate seroprevalence across all periods, fewer than 10% of people had detectable SARS-CoV-2 antibodies. Seroprevalence estimates varied between sexes, across age groups, and between metropolitan/nonmetropolitan areas. Changes from period 1 to 4 were less than 7 percentage points in all jurisdictions and varied across sites. Conclusions and Relevance: This cross-sectional study found that as of September 2020, most persons in the US did not have serologic evidence of previous SARS-CoV-2 infection, although prevalence varied widely by jurisdiction. Biweekly nationwide testing of commercial clinical laboratory sera can play an important role in helping track the spread of SARS-CoV-2 in the US.


Subject(s)
COVID-19/diagnosis , COVID-19/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19 Serological Testing , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Prevalence , Seroepidemiologic Studies , United States/epidemiology , Young Adult
5.
J Clin Microbiol ; 58(11)2020 10 21.
Article in English | MEDLINE | ID: covidwho-721186

ABSTRACT

A total of 1,200 serum samples that were tested for SARS-CoV-2 IgG antibody using the Abbott Architect immunoassay targeting the nucleocapsid protein were run in 3 SARS-CoV-2 IgG immunoassays targeting spike proteins (DiaSorin Liaison, Ortho Vitros, and Euroimmun). Consensus-positive and consensus-negative interpretations were defined as qualitative agreement in at least 3 of the 4 assays. Agreement of the 4 individual assays with a consensus-negative interpretation (n = 610) ranged from 96.7% to 100%, and agreement with a consensus-positive interpretation (n = 584) ranged from 94.3% to 100%. Laboratory-developed inhibition assays were utilized to evaluate 49 consensus-negative samples that were positive in only one assay; true-positive reactivity was confirmed in only 2 of these 49 (4%) samples. These findings demonstrate very high levels of agreement among 4 SARS-CoV-2 IgG assays authorized for emergency use, regardless of antigen target or assay format. Although false-positive reactivity was identified, its occurrence was rare (no more than 1.7% of samples for a given assay).


Subject(s)
Coronavirus Infections , Nucleocapsid , Pandemics , Pneumonia, Viral , SARS Virus , Antibodies, Viral , Betacoronavirus , COVID-19 , COVID-19 Testing , Clinical Laboratory Techniques , Coronavirus Infections/diagnosis , Humans , Immunoassay , Immunoglobulin G , SARS-CoV-2 , Sensitivity and Specificity , Spike Glycoprotein, Coronavirus
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