Surgical masks are thought to retain much of their ability to filter out potential virus particles over repeated use. French consumer watchdog UFC-Que Choisir [“What to Choose”] found surgical masks retained “excellent filtration capacities” even after being washed 10 times at 60 degrees Celsius.
Nevertheless, the World Health Organisation says “medical masks are for single use only” and that you should “discard the mask immediately, preferably into a closed bin”-https://www.scmp.com/lifestyle/health-wellness/article/3117556/can-we-safely-reuse-disposable-face-masks-risks-multiple
