Technologies are generally described for devices for detection of a biofilm by a color change in a moisture-indicating substance, such as a chemical or a dye. The moisture indicating material may be supported by a substrate and sealed to keep moisture from the moisture indicating material. Alternatively, the moisture indicating material may be supported in a pouch and sealed by the pouch. The color change results from an ingress of moisture accompanying growth of a biofilm. The moisture-indicating substance may be used with indwelling or other devices to detect a biofilm. When the biofilm has sufficiently degraded the seal, an ingress of moisture and its accompanying pH may cause a color change in the moisture-indicating substance to signify the presence of the biofilm. Methods of manufacture and use of the disclosed devices are also described.
