Study of the Inactivated COVID-19 Vaccine Contamination in Vaccination Sites — Zigong City, Sichuan Province, China, January, 2021

ABSTRACT

Vaccines are a crucial weapon in combating the global coronavirus disease 2019 (COVID-19) pandemic. At present, China is in a critical period of COVID-19 vaccination, and most of the approved vaccines are developed by inactivated vaccine technology, which contains the complete nucleic acid sequence of the virus (1-2). The inactivated COVID-19 vaccine may contaminate people and environments during the vaccination process, thus triggering a false alarm of the COVID-19 surveillance system. In this study, we selected some vaccination sites to assess the intensity and distribution of vaccine contamination.;;Before field study, we used Reverse Transcription-Polymerase Chain Reaction (RT-PCR) method with kits that produced by Da An Gene and ZJ Bio-Tech to estimate the signal strength of inactivated COVID-19 vaccine (SinovacBiotech). The average Cycle threshold (Ct) value of ORF1Ab /N gene of the vaccine solution was 15.30±0.77, while the Ct value of the kit’s positive control was 28.01±2.38.