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COVID-19 symptoms: a case-control study, Portugal, March-April 2020.

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|February 19, 2021
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Summary
This summary is machine-generated.

General and gastrointestinal symptoms are key indicators for identifying COVID-19 cases. Including these in diagnostic criteria can improve case detection and control the spread of SARS-CoV-2.

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Case–control studycoronavirussymptoms

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Area of Science:

  • Infectious Diseases
  • Public Health
  • Epidemiology

Background:

  • COVID-19 is primarily a respiratory illness but presents with diverse non-respiratory symptoms.
  • Accurate identification of COVID-19 cases is crucial for effective transmission control.

Purpose of the Study:

  • To identify specific symptoms associated with SARS-CoV-2 infection in Portugal.
  • To evaluate the predictive value of general and gastrointestinal symptoms for positive COVID-19 test results.

Main Methods:

  • A negative case-control study design was employed.
  • Twelve symptoms and signs were analyzed as predictors for RT-PCR test results.
  • Unconditional logistic regression with a backward stepwise method was used for model selection.

Main Results:

  • General symptoms (myalgia, headache, fatigue) and gastrointestinal symptoms (diarrhea) showed a strong association with positive SARS-CoV-2 tests (P < 0.001).
  • The logistic regression model identified these symptoms as significant predictors.

Conclusions:

  • Integrating general and gastrointestinal symptoms into COVID-19 case definitions can enhance case identification.
  • Improved case detection through symptom analysis strengthens transmission control strategies for SARS-CoV-2.