A conservation law for virus infection kinetics in vitro

•We derived a conserved quantity from a basic model of viral infection.•We gave a feasible biological interpretation for the conserved quantity.•We calculated the conserved quantity based on cell culture viral experimental data.

Conservation laws are among the most important properties of a physical system, but are not commonplace in biology. We derived a conservation law from the basic model for viral infections which consists in a small set of ordinary differential equations. We challenged the conservation law experimentally for the case of a virus infection in a cell culture. We found that the derived, conserved quantity remained almost constant throughout the infection period, implying that the derived conservation law holds in this biological system. We also suggest a potential use for the conservation law in evaluating the accuracy of experimental measurements.