DS1 has chicken pox. The first spots appeared on Monday, so I think he was infectious from about this time last week, and will probably be infectious for another day or two as they have not scabbed over yet.
We have stayed indoors since he became poorly, and won't allow him to mix with people until we're sure he's no longer infectious.
I also have a DS2 (9 months old), who is showing no signs of illness but obviously could be incubating it.
The NHS guidelines say that the incubation period can last anywhere from 10 to 21 days. So if he had contracted the virus, say, today, that's another three weeks during which he could become infectious, and we may not realise as the spots wouldn't show until afterwards.
For reasons of sanity, after a week indoors with two small DCs, I would rather not shun all human contact for another three weeks. But at the same time I don't want to spread illness unnecessarily. In this weather our options for getting out of the house are fairly limited and generally involve contact with other children, at toddler groups, soft play and friends' houses.
What do people do?