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1.
J Infect Dis ; 224(11): 1873-1877, 2021 12 01.
Article in English | MEDLINE | ID: covidwho-1545974

ABSTRACT

We estimated the distributions of duration of SARS-CoV-2 nucleic acid shedding and time to reinfection among 137 persons with at least 2 positive nucleic acid amplification test (NAAT) results from March to September 2020. We analyzed gaps of varying length between subsequent positive and negative NAAT results and estimated a mean duration of nucleic acid shedding of 30.1 days (95% confidence interval [CI], 26.3-34.5). Mean time to reinfection was 89.1 days (95% CI, 75.3-103.5). Together, these indicate that a 90-day period between positive NAAT results can reliably define reinfection in immunocompetent persons although reinfection can occur at shorter intervals.


Subject(s)
COVID-19 , Emergency Responders , Health Personnel , Reinfection , Virus Shedding , Humans , RNA, Viral , SARS-CoV-2
2.
Clin Infect Dis ; 2021 Nov 15.
Article in English | MEDLINE | ID: covidwho-1522159

ABSTRACT

BACKGROUND: SARS-CoV-2 virus testing among first responders and healthcare personnel who participated in a May-August 2020 serosurvey which assessed spike protein antibodies (S1 region) provided an opportunity to assess reinfection. METHODS: Serology survey data were merged with virus testing results from Rhode Island (March 1, 2020-February 17, 2021) and New York City (March 10-December 14, 2020). Participants with a positive virus test ≥14 days before their serology test were included. Reinfection was defined as a second positive SARS-CoV-2 test result ≥90 days after the first positive test. The association between serostatus and reinfection was assessed with a proportional hazards model adjusting for demographics, exposures, and virus testing frequency. RESULTS: Among 1,572 previously infected persons, 40 (2.5%) were reinfected. Reinfection differed by serostatus: 8.4% among seronegative versus 1.9% among seropositive participants (p<0.0001). Most reinfections occurred among Rhode Island nursing home and corrections (RINHC) personnel (n=30) who were most frequently tested (mean 30.3 tests versus 4.6 for other Rhode Island and 2.3 for New York City participants). The adjusted hazard ratio (aHR) for reinfection in seropositive versus seronegative persons was 0.41 (95% CI 0.20, 0.81). Exposure to a household member with COVID-19 before the serosurvey was also protective (aHR 0.34, 95% CI 0.13, 0.89). CONCLUSIONS: Reinfections were uncommon among previously infected persons over a 9-month period that preceded widespread variant circulation. Seropositivity decreased reinfection risk. Lower reinfection risk associated with exposure to a household member with COVID-19 before the serosurvey may reflect subsequently reduced household transmission among members of previously infected households.

3.
Clin Infect Dis ; 73(9): e3066-e3073, 2021 11 02.
Article in English | MEDLINE | ID: covidwho-1501031

ABSTRACT

BACKGROUND: Reports suggest that some persons previously infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lack detectable immunoglobulin G (IgG) antibodies. We aimed to determine the proportion IgG seronegative and predictors for seronegativity among persons previously infected with SARS-CoV-2. METHODS: We analyzed serologic data collected from healthcare workers and first responders in New York City and the Detroit metropolitan area with a history of a positive SARS-CoV-2 reverse-transcription polymerase chain reaction (RT-PCR) test result and who were tested for IgG antibodies to SARS-CoV-2 spike protein at least 2 weeks after symptom onset. RESULTS: Of 2547 persons with previously confirmed SARS-CoV-2 infection, 160 (6.3%) were seronegative. Of 2112 previously symptomatic persons, the proportion seronegative slightly increased from 14 to 90 days post symptom onset (P = .06). The proportion seronegative ranged from 0% among 79 persons previously hospitalized to 11.0% among 308 persons with asymptomatic infections. In a multivariable model, persons who took immunosuppressive medications were more likely to be seronegative (31.9%; 95% confidence interval [CI], 10.7%-64.7%), while participants of non-Hispanic Black race/ethnicity (vs non-Hispanic White; 2.7%; 95% CI, 1.5%-4.8%), with severe obesity (vs under/normal weight; 3.9%; 95% CI, 1.7%-8.6%), or with more symptoms were less likely to be seronegative. CONCLUSIONS: In our population with previous RT-PCR-confirmed infection, approximately 1 in 16 persons lacked IgG antibodies. Absence of antibodies varied independently by illness severity, race/ethnicity, obesity, and immunosuppressive drug therapy. The proportion seronegative remained relatively stable among persons tested up to 90 days post symptom onset.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Viral , Cohort Studies , Humans , Spike Glycoprotein, Coronavirus
4.
Clin Infect Dis ; 73(3): e822-e825, 2021 08 02.
Article in English | MEDLINE | ID: covidwho-1338686

ABSTRACT

A severe acute respiratory syndrome coronavirus 2 serosurvey among first responder/healthcare personnel showed that loss of taste/smell was most predictive of seropositivity; percent seropositivity increased with number of coronavirus disease 2019 symptoms. However, 22.9% with 9 symptoms were seronegative, and 8.3% with no symptoms were seropositive. These findings demonstrate limitations of symptom-based surveillance and importance of testing.


Subject(s)
COVID-19 , Emergency Responders , Delivery of Health Care , Humans , SARS-CoV-2 , Seroepidemiologic Studies
5.
Emerg Infect Dis ; 27(5): 1505-1508, 2021 05.
Article in English | MEDLINE | ID: covidwho-1262597

ABSTRACT

We evaluated nucleic acid amplification testing (NAAT) for Zika virus on whole-blood specimens compared with NAAT on serum and urine specimens among asymptomatic pregnant women during the 2015-2016 Puerto Rico Zika outbreak. Using NAAT, more infections were detected in serum and urine than in whole blood specimens.


Subject(s)
Pregnancy Complications, Infectious , Zika Virus Infection , Zika Virus , Disease Outbreaks , Female , Humans , Pregnancy , Pregnancy Complications, Infectious/epidemiology , Puerto Rico , Zika Virus Infection/epidemiology
6.
Emerg Infect Dis ; 27(3): 823-834, 2021 03.
Article in English | MEDLINE | ID: covidwho-1100027

ABSTRACT

Healthcare personnel are recognized to be at higher risk for infection with severe acute respiratory syndrome coronavirus 2. We conducted a serologic survey in 15 hospitals and 56 nursing homes across Rhode Island, USA, during July 17-August 28, 2020. Overall seropositivity among 9,863 healthcare personnel was 4.6% (95% CI 4.2%-5.0%) but varied 4-fold between hospital personnel (3.1%, 95% CI 2.7%-3.5%) and nursing home personnel (13.1%, 95% CI 11.5%-14.9%). Within nursing homes, prevalence was highest among personnel working in coronavirus disease units (24.1%; 95% CI 20.6%-27.8%). Adjusted analysis showed that in hospitals, nurses and receptionists/medical assistants had a higher likelihood of seropositivity than physicians. In nursing homes, nursing assistants and social workers/case managers had higher likelihoods of seropositivity than occupational/physical/speech therapists. Nursing home personnel in all occupations had elevated seropositivity compared with hospital counterparts. Additional mitigation strategies are needed to protect nursing home personnel from infection, regardless of occupation.


Subject(s)
COVID-19/epidemiology , Health Personnel/statistics & numerical data , Hospitals/statistics & numerical data , Nursing Homes/statistics & numerical data , Adolescent , Adult , Aged , COVID-19/diagnosis , COVID-19/transmission , Female , Humans , Male , Middle Aged , Occupational Exposure/statistics & numerical data , Odds Ratio , Personal Protective Equipment/statistics & numerical data , Rhode Island/epidemiology , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Seroepidemiologic Studies , Young Adult
7.
Emerg Infect Dis ; 27(2): 669-672, 2021 Feb.
Article in English | MEDLINE | ID: covidwho-1048942

ABSTRACT

Despite mitigation efforts, 2 coronavirus disease outbreaks were identified among office workers in Washington, DC. Moderate adherence to workplace mitigation efforts was reported in a serologic survey; activities outside of the workplace were associated with infection. Adherence to safety measures are critical for returning to work during the pandemic.


Subject(s)
COVID-19 Serological Testing/statistics & numerical data , COVID-19/epidemiology , Disease Outbreaks/prevention & control , Infection Control/statistics & numerical data , Workplace/statistics & numerical data , Adult , Antibodies, Viral/blood , COVID-19/blood , COVID-19/diagnosis , District of Columbia/epidemiology , Female , Health Plan Implementation , Humans , Infection Control/methods , Male , Middle Aged , SARS-CoV-2/immunology , Seroepidemiologic Studies
8.
Emerg Infect Dis ; 27(3): 796-804, 2021 03.
Article in English | MEDLINE | ID: covidwho-1045534

ABSTRACT

We conducted a serologic survey in public service agencies in New York City, New York, USA, during May-July 2020 to determine prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among first responders. Of 22,647 participants, 22.5% tested positive for SARS-CoV-2-specific antibodies. Seroprevalence for police and firefighters was similar to overall seroprevalence; seroprevalence was highest in correctional staff (39.2%) and emergency medical technicians (38.3%) and lowest in laboratory technicians (10.1%) and medicolegal death investigators (10.8%). Adjusted analyses demonstrated association between seropositivity and exposure to SARS-CoV-2-positive household members (adjusted odds ratio [aOR] 3.52 [95% CI 3.19-3.87]), non-Hispanic Black race or ethnicity (aOR 1.50 [95% CI 1.33-1.68]), and severe obesity (aOR 1.31 [95% CI 1.05-1.65]). Consistent glove use (aOR 1.19 [95% CI 1.06-1.33]) increased likelihood of seropositivity; use of other personal protective equipment had no association. Infection control measures, including vaccination, should be prioritized for frontline workers.


Subject(s)
Antibodies, Viral/blood , COVID-19/epidemiology , Emergency Responders/statistics & numerical data , Adolescent , Adult , Aged , COVID-19 Serological Testing , Female , Humans , Male , Middle Aged , New York City/epidemiology , Obesity/epidemiology , Personal Protective Equipment , Prevalence , Seroepidemiologic Studies , Young Adult
9.
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
10.
Open Forum Infect Dis ; 8(1): ofaa555, 2021 Jan.
Article in English | MEDLINE | ID: covidwho-933880

ABSTRACT

BACKGROUND: There is a need for validated and standardized severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) quantitative immunoglobulin G (IgG) and neutralization assays that can be used to understand the immunology and pathogenesis of SARS-CoV-2 infection and support the coronavirus disease 2019 (COVID-19) pandemic response. METHODS: Literature searches were conducted to identify English language publications from peer-reviewed journals and preprints from January 2020 through November 6, 2020. Relevant publications were reviewed for mention of IgG or neutralization assays for SARS-CoV-2, or both, and the methods of reporting assay results. RESULTS: Quantitative SARS-CoV-2 IgG results have been reported from a limited number of studies; most studies used in-house laboratory-developed tests in limited settings, and only two semiquantitative tests have received US Food and Drug Administration (FDA) Emergency Use Authorization (EUA). As of November 6, 2020, there is only one SARS-CoV-2 neutralization assay with FDA EUA. Relatively few studies have attempted correlation of quantitative IgG titers with neutralization results to estimate surrogates of protection. The number of individuals tested is small compared with the magnitude of the pandemic, and persons tested are not representative of disproportionately affected populations. Methods of reporting quantitative results are not standardized to enable comparisons and meta-analyses. CONCLUSIONS: Lack of standardized SARS-CoV-2 quantitative IgG and neutralization assays precludes comparison of results from published studies. Interassay and interlaboratory validation and standardization of assays will support efforts to better understand antibody kinetics and longevity of humoral immune responses postillness, surrogates of immune protection, and vaccine immunogenicity and efficacy. Public-private partnerships could facilitate realization of these advances in the United States and worldwide.

11.
Emerg Infect Dis ; 26(12): 2863-2871, 2020 12.
Article in English | MEDLINE | ID: covidwho-781934

ABSTRACT

To estimate seroprevalence of severe acute respiratory syndrome 2 (SARS-CoV-2) among healthcare, first response, and public safety personnel, antibody testing was conducted in emergency medical service agencies and 27 hospitals in the Detroit, Michigan, USA, metropolitan area during May-June 2020. Of 16,403 participants, 6.9% had SARS-CoV-2 antibodies. In adjusted analyses, seropositivity was associated with exposure to SARS-CoV-2-positive household members (adjusted odds ratio [aOR] 6.18, 95% CI 4.81-7.93) and working within 15 km of Detroit (aOR 5.60, 95% CI 3.98-7.89). Nurse assistants (aOR 1.88, 95% CI 1.24-2.83) and nurses (aOR 1.52, 95% CI 1.18-1.95) had higher likelihood of seropositivity than physicians. Working in a hospital emergency department increased the likelihood of seropositivity (aOR 1.16, 95% CI 1.002-1.35). Consistently using N95 respirators (aOR 0.83, 95% CI 0.72-0.95) and surgical facemasks (aOR 0.86, 95% CI 0.75-0.98) decreased the likelihood of seropositivity.


Subject(s)
COVID-19/epidemiology , Emergency Responders/statistics & numerical data , Health Personnel/statistics & numerical data , Personal Protective Equipment/statistics & numerical data , Adolescent , Adult , Aged , COVID-19/blood , COVID-19/transmission , COVID-19 Serological Testing , Female , Humans , Male , Michigan/epidemiology , Middle Aged , Pandemics/statistics & numerical data , SARS-CoV-2/isolation & purification , Seroepidemiologic Studies , Surveys and Questionnaires , Young Adult
12.
Immunity ; 53(1): 1-5, 2020 07 14.
Article in English | MEDLINE | ID: covidwho-611679

ABSTRACT

The development, validation, and appropriate application of serological assays to detect antibodies to SARS-CoV-2 are essential to determining seroprevalence of this virus in the United States and globally and in guiding government leadership and the private sector on back-to-work policies. An interagency working group of the US Department of Health and Human Services convened a virtual workshop to identify knowledge gaps and key outstanding scientific issues and to develop strategies to fill them. Key outcomes of the workshop included recommendations for (1) advancing serology assays as a tool to better understand SARS-CoV-2 infection and (2) conducting crucial serology field studies to advance an understanding of immunity to SARS-CoV-2, leading to protection and duration of protection, including the correlation between serological test results and risk of reinfection.


Subject(s)
Antibodies, Viral/blood , Betacoronavirus/immunology , Coronavirus Infections/immunology , Pneumonia, Viral/immunology , Seroepidemiologic Studies , Serologic Tests/methods , COVID-19 , Coronavirus Infections/blood , Humans , Pandemics , Pneumonia, Viral/blood , SARS-CoV-2
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