A new study conducted by several prestigious research institutions in Russia has highlighted a potential environmental issue related to the contamination of wastewater with the SARS-CoV-2 virus, which causes COVID-19. The study has drawn attention to the potential impact on reptiles, specifically crocodiles.
The SARS-CoV-2 virus, which has had a profound global impact, is believed to have originated from bats or pangolins. It has shown its ability to infect various mammalian species, including reverse zoonotic transmission to minks and domestic hamsters.
Early on in the pandemic, concerns were raised about the possibility of fecal-oral transmission and environmental contamination of the virus. Although viral RNA has been found in feces, the isolation of infectious virus from wastewater and river water samples has been rare. This may be due to the low concentration of the virus and its loss of infectious properties during testing.
The interaction between SARS-CoV-2 and animals in aquatic ecosystems is still not well understood. Recent research has detected viral RNA in the digestive systems of bivalve mollusks and various aquatic or semi-aquatic mammals, raising concerns about the susceptibility of fish and reptiles to the virus.
To address these knowledge gaps, researchers focused on freshwater fish and reptiles in their study. They examined the replication efficiency of SARS-CoV-2 in various poikilothermic vertebrates, including the eastern box turtle, Nile crocodile, and loggerhead sea turtle.
The study found that the temperature had a significant influence on the replication efficiency of SARS-CoV-2 in susceptible cell cultures. Reptile cells, specifically those from the eastern box turtle and Nile crocodile, showed high susceptibility to the virus at an ambient temperature of 29 °C. In contrast, fish cell cultures showed no susceptibility to SARS-CoV-2 infection.
The researchers emphasized the importance of considering temperature variations when studying the dynamics of SARS-CoV-2 infection in different host species. They also compared the susceptibility of reptile cells to the widely used Vero E6 cell culture model and found temperature-dependent variations.
The circulation of SARS-CoV-2 among animals continues to present ongoing challenges. The study’s findings suggest the possibility of SARS-CoV-2 contaminating aquatic ecosystems and effectively replicating in certain reptile species. As the virus continues to evolve, the risk of new variants with unpredictable infectious properties remains a concern.
Monitoring and understanding the virus’s interactions with diverse host species are crucial for mitigating potential threats to both animal and human health. Further research is needed to explore the broader implications of SARS-CoV-2 in environmental reservoirs and its impact on wildlife conservation efforts. It is essential to develop comprehensive strategies to protect ecosystems and public health from the complexities of SARS-CoV-2 in different environments.