Viruses on plastic waste pose new antibiotic resistance risks

Plastic pollution does more than litter landscapes and oceans. According to a new perspective article published in Biocontaminant, viruses living on plastic surfaces may play an underrecognized role in spreading antibiotic resistance, raising concerns for environmental and public health worldwide.

When plastics enter natural environments, they quickly become coated with microbial biofilms known as the plastisphere. These plastic associated communities are already known hotspots for antibiotic resistance genes. The new study highlights that viruses, the most abundant biological entities on Earth, could be key players in moving these resistance genes between microbes.

"Most research has focused on bacteria in the plastisphere, but viruses are everywhere in these communities and interact closely with their hosts," said corresponding author Dong Zhu of the Chinese Academy of Sciences.

Our work suggests that plastisphere viruses may act as hidden drivers of antibiotic resistance dissemination."

Dong Zhu, Chinese Academy of Sciences

Viruses can transfer genetic material between bacteria through a process called horizontal gene transfer. In plastisphere biofilms, where microbes are densely packed, viruses may more easily shuttle resistance genes across species, including to potential pathogens. Some viruses also carry auxiliary metabolic genes that can boost bacterial survival under stressful conditions, such as exposure to antibiotics or pollutants, indirectly favoring resistant microbes.

The authors point out that viral behavior appears to differ between environments. In aquatic plastispheres, viruses are more likely to adopt life strategies that promote gene transfer, potentially increasing resistance risks. In soils, viruses may instead limit resistant bacteria by killing their hosts. These contrasting roles highlight the need to consider environmental context when assessing the risks of plastic pollution.

"This perspective emphasizes that antibiotic resistance linked to plastics cannot be fully understood without including viral ecology," said lead author Xue Peng Chen. "Incorporating viruses into a One Health framework will help us better evaluate the long term consequences of plastic pollution."

The authors call for future studies to directly measure gene exchange between viruses and bacteria on plastics and to refine methods for detecting virus encoded resistance genes. Such insights could inform environmental monitoring and plastic waste management strategies aimed at reducing antibiotic resistance risks.