'Herd-Immunity-on-a-Chip' recreates viral transmission within a simulated population

A microfluidic platform, dubbed Herd-Immunity-on-a-Chip, has been developed by researchers at Sungkyunkwan University to study viral transmission within a controlled laboratory environment. Led by Professors Sungsu Park and Byung Mook Weon, the team created a centimeter-scale device with 444 interconnected hexagonal microchambers to mimic human social structures. Lung fibroblast cells were used as the population, with some cells representing those with varying levels of susceptibility to infection.

The researchers simulated the spread of a virus through the chip by monitoring how infection propagated—or failed to propagate—among the cells over a period of seven days. Their findings demonstrate how population structure influences viral spread. When susceptible cells were densely packed or the initial number of infected cells was high, viral transmission accelerated due to increased contact between cells.

Conversely, when the proportion of non-susceptible cells reached 80% or more, transmission routes became fragmented and viral spread was effectively curtailed, mimicking herd immunity on a chip.

Moreover, the study showed that restricting cell movement slowed transmission, effectively replicating the impact of social distancing measures. This groundbreaking research, published in Advanced Science, is the first to directly model and validate viral transmission and herd immunity on a laboratory chip, moving beyond traditional cell-infection assays.

The platform has the potential to predict population-level protection needed against new viral variants, inform effective distancing strategies, and quickly assess the efficacy of therapeutic or antiviral interventions.