George Gillespie, one of the authors of the Westminster Confession of Faith, addressed the question about churches meeting in adverse circumstances because of plague or persecution.
He argues that a local church is allowed to cease or break into smaller meetings for a time, even years,.
A multitude may be one Church, though they do not meet together into one place for the worship of God: for example, it may fall forth, that a congregation cannot meet together into one, but into diverse places, and this may continue so for some years together, either by reason of persecution, or by means of the plague, or because they have not such a large parish-Church as may contain them all, so that a part of them must meet in some other place: but a multitude cannot be one Church, unless they communicate in the same Church government, and under the same governors (by one Church I mean one Ecclesiastical Republic) even as the like union under civil government and governors maketh one corporation: . . . (An Assertion of the Government of the Church of Scotland… (Edinburgh, 1641), 2nd pt., ch. 3, 145.)
Reformed Books Online has a treasure trove of historical information with quotes on social distancing and the adaptation of the Church in a time of spreading disease.