Evaluation of SARS-CoV-2 Existence in Blood, Urine, and Rectal Swab in Positive Patients with Different Virus Titers

Abstract

Background: Coronavirus disease 2019 (COVID-19) is an infectious disease caused by a newly discovered coronavirus. Understanding the spreading routes of SARS-CoV-2 is crucial for patient management and defining biosafety strategies for public and health care workers. Objectives: In the current study, the virus shedding in the upper respiratory as well as blood, stool, and urine specimens of infected patients, was examined using quantitative real-time PCR assay (qRT-PCR). Methods: The samples of 50 positive patients with high, moderate, and low virus titers in their respiratory specimens were collected. All specimens were subjected to RNA extraction and RT-qPCR assay using two different internally-controlled test systems. Results: The results indicated that no positive results were observed in the urine samples of all patients. The viral genome was diagnosed in 5% of blood and 3.3% of rectal swab samples. The Cq (Cycle of quantification)-values of positive results on the stool and blood samples were always higher than the Cq-value of the respiratory specimen of the same patient. Conclusions: SARS-CoV-2 is mainly detected in the respiratory samples, and the virus is not detectable in the urine. The importance of viremia and the existence of the virus in feces in virus spread in the human population needs further investigation.