SUMMARY: This article talks about how antibiotics (specifically neomycin) and other positively charged substances can help viruses spread (the virus studied in this case has a negatively charged exterior). Most of the experiments looked at the reasons why the virus was able to form more plaques with the antibiotic. One would think that the conclusion would be something along the lines of “antibiotics have an effect on viruses”; however, the antibiotics didn’t change the viruses physically. Researchers found that the positively charged neomycin helped the negatively charged virus diffuse and when negatively charged substances were used in the agar plate, the virus was inhibited.
LESSON COMMENT: An interesting article to show students the importance of drawing conclusions based on the evidence presented in the results. A good activity I did with my students was to talk and analyze this experiment, then try to predict how a mainstream news site might write a headline that could then mislead readers into thinking that antibiotics can be used to treat viruses. In fact, the results are the opposite: antibiotics help viruses spread.
This article also illustrates the importance of charges on molecules and their interactions. The agar, the antibiotic, and the viral proteins all have charges that interact with each other. Changes in the material and thus the charges will inhibit or encourage the spread of the virus.
Acevedo, M. W., & Pfeiffer, J. K. (2018). The Antibiotic Neomycin Enhances Coxsackievirus Plaque Formation. doi:10.1101/471284