How Long Can a Dead Body Remain Infectious?: Postmortem Nasopharyngeal Swabs and SARS-CoV-2 Culture in a Corpse Over an 87-Day Period

A Year of Deaths Due to or With COVID-19 Under Universal Postmortem Testing in San Francisco

ABSTRACT

The Health Officer of the City and County of San Francisco, California, issued the order that all decedents were required to have a documented COVID-19 test effective from June 2020 to June 2021. The justification for the requirement was that complete data on COVID-19 status at the time of death were needed to help protect first responders and funeral home workers, identify missed cases, and characterize the places of death for otherwise unknown COVID-19 cases. To fill the gap in COVID-19 testing for all decedents, particularly among persons dying outside of hospitals, a specialized Decedent Testing Unit was created along with an increased capacity of the Office of the Chief Medical Examiner. From July 1, 2020, to June 30, 2021, the Decedent Testing Unit and Office of the Chief Medical Examiner provided postmortem testing results for 2776 decedents. Of these, 80 tested positive for COVID-19 for a positivity rate of 2.97%. The largest number of COVID-19-positive specimens were collected from persons who died at home (n = 37, 46.3%), followed by those who died in hospice (n = 20, 25.0%), other places outside of homes or facilities (n = 8, 10.0%), and in skilled nursing or long-term care facilities (n = 7, 8.8%). Follow-up of California death records found that 17 of these 80 cases (21.3%) had COVID-19 listed as one of the causes of death, 22 (27.5%) mentioned COVID-19 under "other conditions," and 41 (51.3%) made no mention of COVID-19. In the context of providing the COVID-19 status of decedents not otherwise known to have infection, our data help gauge the likelihood of missing deaths due to or with COVID-19 and inform future public health decisions on whether to require universal postmortem testing with COVID-19 resurgences or with new deadly epidemics.

High titers of infectious SARS-CoV-2 in corpses of patients with COVID-19

OBJECTIVES

The prolonged presence of infectious SARS-CoV-2 in deceased patients with COVID-19 has been reported. However, infectious virus titers have not been determined. Such information is important for public health, death investigation, and handling corpses. The aim of this study was to assess the level of SARS-CoV-2 infectivity in the corpses of patients with COVID-19.

METHODS

We collected 11 nasopharyngeal swabs and 19 lung tissue specimens from 11 autopsy cases with COVID-19 in 2021. We then investigated the viral genomic copy number by real-time reverse transcription-polymerase chain reaction and infectious titers by cell culture and virus isolation.

RESULTS

Infectious virus was present in six of 11 (55%) cases, four of 11 (36%) nasopharyngeal swabs, and nine of 19 (47%) lung specimens. The virus titers ranged from 6.00E + 01 plaque-forming units/ml to 2.09E + 06 plaque-forming units/g. In all cases in which an infectious virus was found, the time from death to discovery was within 1 day and the longest postmortem interval was 13 days.

CONCLUSION

The corpses of patients with COVID-19 may have high titers of infectious virus after a long postmortem interval (up to 13 days). Therefore, appropriate infection control measures must be taken when handling corpses.