Asymptomatic and Mild SARS-CoV-2 Infections in a Hungarian Outpatient Cohort in the First Year of the COVID-19 Pandemic
Abstract
:1. Introduction
2. Materials and Methods
2.1. Collection of Blood and Nasopharyngeal Swab Samples
2.2. Questionnaire
2.3. SARS-CoV-2 RT-PCR
2.4. SARS-CoV-2 Culture, Inactivation, and Purification
2.5. Anti-SARS-CoV-2 IgG and IgA Antibody Testing
2.6. Data Analysis
3. Results
3.1. Clinical Symptoms, Seroprevalence, and RT-PCR Positivity of Participants without Known COVID-19 Contacts
3.2. Symptoms, Seroprevalence, and RT-PCR Positivity of Participants with Known COVID-19 Contacts
3.3. The Relation of IgG and IgA Antibodies in the Participants with or without Previous COVID-19 Contacts
3.4. Coexisting Diseases and COVID-19 Symptoms, in Context with PCR Positivity, in Participants with or without Previous COVID-19 Contacts
3.5. Direct Comparison of PCR Positivity and Symptoms in Participants with or without Previous COVID-19 Contacts
3.6. Repeated Sampling and Testing of 33 Selected Participants: IgG Positivity, PCR Positivity, and Symptoms
4. Discussion
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Characteristics | Total No. of Tested People | Time Period | No. of People with Positive RT-PCR-Results | Percentage of Positive People (95% CI) |
---|---|---|---|---|
Symptoms | 1023 of 1023 | April 2020–August 2020 | 129 | 12.6 (10.64–14.80) |
IgG antibodies | 1023 of 1023 | April 2020–August 2020 | 39 | 3.8 (2.72–5.17) |
Symptoms | 3120 of 3120 | September 2020–March 2021 | 348 | 11.1 (10.07–12.31) |
IgG antibodies | 2748 of 3120 | September 2020–March 2021 | 449 | 16.3 (14.98–17.78) |
IgA antibodies | 2409 of 3120 | September 2020–March 2021 | 177 | 7.3 (6.34–8.46) |
Viral RNA | 2423 of 3120 | September 2020–March 2021 | 204 | 8.4 (7.34–9.6) |
Symptoms | 4143 of 4143 | April 2020–March 2021 | 477 | 11.5 (10.56–12.52) |
IgG antibodies | 3771 of 4143 | April 2020–March 2021 | 488 | 12.9 (11.89–14.05) |
Characteristics | Total No. of Tested People | Time Period | No. of People with Positive RT-PCR-Results | Percentage of Positive People (95% CI) |
---|---|---|---|---|
Symptoms | 185 of 185 | April 2020–May 2020 | 80 | 43.2 (35.99–50.71) |
IgG antibodies | 185 of 185 | April 2020–May 2020 | 9 | 4.9 (2.25–9.03) |
Symptoms | 409 of 409 | September 2020–March 2021 | 233 | 57.0 (52.01–61.82) |
IgG antibodies | 386 of 409 | September 2020–March 2021 | 52 | 13.5 (10.23–17.29 |
IgA antibodies | 320 of 409 | September 2020–March 2021 | 31 | 9.7 (6.68–13.47) |
Viral RNA | 335 of 409 | September 2020–March 2021 | 47 | 14.0 (10.46–18.16) |
Symptoms | 594 of 594 | April 2020–March 2021 | 313 | 52.6 (48.59–56.77) |
IgG antibodies | 571 of 594 | April 2020–March 2021 | 61 | 10.6 (8.27–13.51) |
Symptoms * | PCR-Positive Participants | % | PCR-Negative Participants | % | p-Value |
---|---|---|---|---|---|
n = 204 | n = 2219 | ||||
cough | 40 | 19.6 | 68 | 3.1 | <0.001 |
fatigue | 33 | 16.2 | 98 | 4.4 | <0.001 |
headache | 33 | 16.2 | 125 | 5.6 | <0.001 |
sore throat | 27 | 13.2 | 80 | 3.6 | <0.001 |
rhinitis | 24 | 11.8 | 84 | 3.8 | <0.001 |
chills | 21 | 10.3 | 32 | 1.4 | <0.001 |
myalgia | 23 | 11.3 | 38 | 1.7 | <0.001 |
anosmia | 15 | 7.4 | 19 | 0.9 | <0.001 |
dysgeusia | 15 | 7.4 | 19 | 0.9 | <0.001 |
fever | 14 | 6.9 | 19 | 0.9 | <0.001 |
chest pain | 7 | 3.4 | 22 | 1.0 | 0.002 |
gastrointestinal symptoms | 6 | 2.9 | 13 | 0.6 | <0.001 |
shortness of breath | 3 | 1.5 | 13 | 0.6 | 0.135 |
Symptoms * | PCR-Positive Participants | PCR-Negative Participants | |||
---|---|---|---|---|---|
n = 47 | % | n = 288 | % | p-Value | |
sore throat | 22 | 46.8 | 59 | 20.5 | <0.001 |
cough | 20 | 42.6 | 41 | 14.2 | <0.001 |
fatigue | 23 | 48.9 | 57 | 19.8 | <0.001 |
rhinitis | 20 | 42.6 | 57 | 19.8 | 0.001 |
headache | 20 | 42.6 | 101 | 35.1 | 0.322 |
myalgia | 26 | 55.3 | 22 | 7.6 | <0.001 |
anosmia | 11 | 23.4 | 9 | 3.1 | <0.001 |
dysgeusia | 11 | 23.4 | 9 | 3.1 | <0.001 |
chills | 12 | 25.5 | 20 | 6.9 | <0.001 |
fever | 10 | 21.3 | 9 | 3.1 | <0.001 |
chest pain | 5 | 10.6 | 8 | 2.8 | 0.010 |
shortness of breath | 5 | 10.6 | 15 | 5.2 | 0.145 |
gastrointestinal symptoms | 0 | 0.0 | 19 | 6.6 | 0.070 |
Groups | No. of PCR-Positive People | No. and Percentage PCR-Positive People with Symptoms | No. and Percentage of PCR-Positive People without Symptoms |
---|---|---|---|
Participants without COVID-19 contact | 204 | 53 (26.0) *,+ | 151 (74.0) + |
Participants with COVID-19 contact | 47 | 36 (76.6) *,× | 11 (23.4) × |
Participants | PCR-Positive | IgG-Positive | IgG-Negative |
---|---|---|---|
10 with symptoms | 4 (1 of 3–4 samples was positive) | 2 | 2 |
6 (more than 1 of 3–4 samples were positive) | 2 | 4 | |
23 without symptoms | 8 (1 of 3–4 samples was positive) | 3 | 5 |
12 (more than 1 of 3–4 samples were positive) | 1 | 11 | |
3 (intermittent positive and negative samples) | 1 | 2 |
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Jankovics, I.; Müller, C.; Gönczöl, É.; Visontai, I.; Varga, I.; Lőrincz, M.; Kuti, D.; Hasitz, Á.; Malik, P.; Ursu, K.; et al. Asymptomatic and Mild SARS-CoV-2 Infections in a Hungarian Outpatient Cohort in the First Year of the COVID-19 Pandemic. Trop. Med. Infect. Dis. 2023, 8, 204. https://doi.org/10.3390/tropicalmed8040204
Jankovics I, Müller C, Gönczöl É, Visontai I, Varga I, Lőrincz M, Kuti D, Hasitz Á, Malik P, Ursu K, et al. Asymptomatic and Mild SARS-CoV-2 Infections in a Hungarian Outpatient Cohort in the First Year of the COVID-19 Pandemic. Tropical Medicine and Infectious Disease. 2023; 8(4):204. https://doi.org/10.3390/tropicalmed8040204
Chicago/Turabian StyleJankovics, István, Cecília Müller, Éva Gönczöl, Ildikó Visontai, István Varga, Márta Lőrincz, Dávid Kuti, Ágnes Hasitz, Péter Malik, Krisztina Ursu, and et al. 2023. "Asymptomatic and Mild SARS-CoV-2 Infections in a Hungarian Outpatient Cohort in the First Year of the COVID-19 Pandemic" Tropical Medicine and Infectious Disease 8, no. 4: 204. https://doi.org/10.3390/tropicalmed8040204