Evaluation of Rt-PCR Cycle Threshold Values of SARS-CoV-2 and epidemiological datas of COVID-19 patients

Abstract

Introduction: COVID-19 infection is diagnosed by RT-PCR. In this test results interpreted according to the cycle threshold (Ct) values, provide indirect measurements of viral load. In this study we aimed to the evalaute the relationship between Ct values and demographics and sypmtoms of patients. Material and Methods: The nasopharyngeal swab of the patients suspected with COVID-19 were collected and tested by RT-PCR for SARS-CoV-2. Demographics, medical history, timelines for exposure and symptoms of the patients diagnosed as COVID-19 by RT-PCRwere obtained from the hospital information system. Results: Total of 619 patient result was enrolled in the study. Ct values were determined as 24.74 (20.95-27.64) for 18> years-old and 22.85 (20.14-26.22) ≥18 years-old, there was no statistically difference according to the age among Ct values. Hypertension was the most common comorbid disease (13.3%) among COVID-19 patients. A positive correlation was detected among the onset of the symptoms and Ct values, Ct values were lowest (corresponding to a higher viral RNA concentration) soon after symptom onset. Patients who had fever, headache, muscle-joint pain significantly had lower Ct values were than patients who did not have these sypmtoms. Conclusion: It is important to early testing for SARS-CoV-2 among persons who have respiratory symptoms, and isolation of them when their viral load and transmission rate is higher.

Keywords

• Sars-Cov2
• Cycle treshold value
• COVID-19
• epidemiology

SARS-CoV-2'nin Rt-PCR Döngüsü Eşik Değerlerinin ve COVID-19 hastalarının epidemiyolojik verilerinin değerlendirilmesi

Abstract

Giriş: COVID-19 enfeksiyonu, RT-PCR ile teşhis edilmektedir. Döngü eşiği (Ct) değerlerine göre yorumlanan bu test sonuçları viral yükün indirekt ölçümlerini sağlar. Bu çalışmada hastaların demografik özellikleri ve semptomları ile Ct değerleri arasındaki ilişkiyi değerlendirmeyi amaçladık. Gereç ve Yöntemler: COVID-19 şüphesi olan hastaların nazofaringeal sürüntüleri toplandı ve SARS-CoV-2 için RT-PCR ile test edildi. RT-PCR ile COVID-19 tanısı alan hastaların demografik bilgileri, tıbbi öyküleri, maruziyet zaman çizelgeleri ve semptomları hastane bilgi sisteminden elde edildi. Bulgular: Toplam 619 hasta sonucu çalışmaya dahil edildi. Ct değerleri 18> yaş için 24,74 (20,95-27,64) ve 22,85 (20,14-26,22) ≥18 yaş olarak belirlendi, Ct değerleri arasında yaşa göre istatistiksel olarak fark yoktu. Hipertansiyon, COVID-19 hastalarında en sık görülen yandaş hastalık (%13,3) oldu. Semptomların başlangıcı ile Ct değerleri arasında pozitif bir korelasyon saptandı, Ct değerleri semptom başlangıcından hemen sonra en düşüktü (daha yüksek bir viral RNA konsantrasyonuna karşılık gelir). Ateş, baş ağrısı, kas-eklem ağrısı olan hastalarda Ct değerleri, bu semptomları olmayan hastalara göre anlamlı olarak daha düşüktü. Sonuç: Solunum yolu semptomları olan kişilerde SARS-CoV-2 için erken test yapılması, viral yük ve bulaşma hızlarının yüksek olduğu zamanlarda izole edilmesi önemlidir.

Keywords

• Sars-Cov2
• Döngü eşik değeri
• COVID-19
• epidemiyoloji

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