The COVID-19 pandemic continues to affect millions of people worldwide. Although SARS-CoV-2 is a respiratory virus, there is growing concern that the disease could cause damage and pathology outside the lungs, including in the genital tract. Studies suggest that SARS-CoV-2 infection can damage the testes and reduce testosterone levels, but the underlying mechanisms are unknown and evidence of virus replication in testicular cells is lacking. We infected golden Syrian hamsters intranasally, a model for mild human COVID-19, and detected viral RNA in testes samples without histopathological changes up to one month post-infection. Using an ex vivo infection model, we detected SARS-CoV-2 replication in hamster testicular cells. Taken together, our data raise the possibility that testes damage observed in severe cases of COVID-19 could be partly explained by direct SARS-CoV-2 infection of the testicular cells.

Introduction: In response to a series of biosafety incidents in 2014, the White House directed two high-level expert committees to analyze biosafety and biosecurity in U.S. laboratories and make recommendations for work with select agents and toxins. Overall, they recommended 33 actions to address areas related to national biosafety, including promoting a culture of responsibility, oversight, outreach and education, applied biosafety research, incident reporting, material accountability, inspection processes, regulations and guidelines, and determining the necessary number of high-containment laboratories in the United States. Methods: The recommendations were collected and grouped into categories previously defined by the Federal Experts Security Advisory Panel and the Fast Track Action Committee. Open-source materials were examined to determine what actions had been taken to address the recommendations. The actions taken were compared against the reasoning provided in the committee reports to determine if the concerns were sufficiently addressed. Results: In this study, we found that 6 recommendations were not addressed and 11 were insufficiently addressed out of 33 total recommended actions. Discussion and Conclusion: Further work is needed to strengthen biosafety and biosecurity in U.S. laboratories handling regulated pathogens (biological select agents and toxins [BSAT]). These carefully considered recommendations should now be enacted, including determining if there is sufficient high-containment laboratory space for response to a future pandemic, developing a sustained applied biosafety research program to improve our understanding of how high-containment research should be performed, bioethics training to educate the regulated community on the consequences of unsafe practices in BSAT research, and the creation of a no-fault incident reporting system for biological incidents, which may inform and improve biosafety training. Significance: The work presented in this study is significant because previous incidents that occurred in Federal laboratories highlighted shortcomings in the Federal Select Agent Program and the Select Agent Regulations. Progress was made on implementing recommendations to address the shortcomings, but efforts were lost or forgotten over time. The COVID-19 pandemic has provided a brief window of interest in biosafety and biosecurity, and an opportunity to address these shortcomings to increase readiness for future disease emergencies.

Background: Venezuelan equine encephalitis virus (VEEV) is an arbovirus endemic to the Americas, for which no vaccines or antiviral agents have been approved. TC-83 and V3526 are the best-characterized vaccine candidates for VEEV. Both are live-attenuated vaccines and have been associated with safety concerns, although fewer concerns exist for V3526. A previous attempt to improve the TC-83 vaccine focused on further attenuating the vaccine by adding mutations that alter the error-incorporation rate of the RNA-dependent RNA polymerase (RdRp). Methods: The research herein examined the effects of these RdRp mutations in V3526 by cloning the 3X and 4X strains, assessing vaccine efficacy against challenge in adult female CD-1 mice, examining neutralizing-antibody titers, investigating vaccine tissue tropism, and testing the stability of the mutant strains. Results: The V3526 RdRp mutants exhibited less tissue tropism in the spleen and kidney than the wild-type V3526, while maintaining vaccine efficacy. Illumina sequencing indicated that the RdRp mutations reverted to wild-type V3526 after five passages in murine pup brains. Conclusions: The observed genotypic reversion is likely to be of limited concern, because wild-type V3526 remains an effective vaccine capable of providing protection. Our results indicate that the V3526 RdRp mutants may be a safer vaccine design than the original V3526.