Questions about Noro

[mhp8982]

After everything I've been dealing with for the past few months.. I've done a lot of research. I'm very confused. I've been trying to figure out if it's possible that my stepson had a virus 3 weeks ago.. and the reason why he's not catchign the one his 2 brothers and step sister had this past weekend.. could it be because he had the same strain and is immune? Or maybe having that one 3 weeks ago just built up his immune system fighting ability.?

I know there are many many strains of norovirus.. and everything I've read says havign one will only offer a short term immunity to that specific strain. And so with many going around, they can get it again over and over.

While there are many strains out there and they do mutate.. are there really THAT many strains out there at a single time? Or is it more like the real flu (influenza) where there are 2 or 3 strains usually circulating.. Because I find it odd, if there are so many strains going around at once, why is it most people..even children hardly ever get it more than once.. maybe twice in a year (I know there are exceptions if a child is immune compromised and/or children v* for other reasons too) If there really are many virus's at once.. and no immunity except to the specific strain how is this? You'd think they'd be getting a real SV* every other week? But that's not the case. So, if indeed there are many virus's at once.. wouldn't that mean there is probably some sort of protection from the other strains? I mean some sort of antibodies to help the body fight harder. After having one already... otherwise it would mean there's only a couple of strains going around at a given time? I mean especially with children.. because they do have poor hygiene and share things with their friends at school and siblings.. but they still generally aren't sick with SV's more than once a year..for the most part.

And another thing.. if we as adults don't have some sort of immunity to these strains.. why is it a lot of times parents can skip out on catching what their children bring in? Even ones who are not emet or stressed or worried about it. And I'm not talking about rotavirus.. I'm talking about noro.. because I know the difference. I've seen noro type virus's go through all of the kids and none of the adults get it at all? I know we have better hygiene.. but I know in these cases I've seen some of the adults involved aren't much better than the kids.. still kissing on the lips and sharing things with the kids....

Sorry.. I'm just wondering about all of this.. because I can't find any clear answers online... so I was just wanting some take from the rest of you. I know you all probably research as much as I do.

Thanks in advance for your help!