The World Prison Brief database now has a regularly updated page of information on COVID19 in prisons worldwide and contains news articles we've been able to source so far, organised by region and country, along with guidance, reports and other initiatives. https://www.prisonstudies.org/news/news-covid-19-and-prisons
Prison Insider is also collating reports on COVID-19 in prisons https://www.prison-insider.com/en/articles/coronavirus-la-fievre-des-prisons
Generic COVID-19 portals for information (not prison specific)
ECDC - website on COVID-19
ECDC - Threat Reports App
COVID-19 Online Libraries
WHO - Global research on COVID-19. Database of publications on COVID-19.
LitCovid - curated literature hub for tracking up-to-date scientific information about COVID-19.
EPPI Centre - COVID-19: a living systematic map of the evidence.
Cochrane - Special collections on COVID-19