How Long Between Exposure to Gerns and Sickness Developing?

3-4 days. If we know we have been exposed to a cold or flu, I start watching after 3 days, make my kids go to bed early, take vitamin C, take a nap, eat soup. Sometimes they'll develop a sore throat and feel tired around that time, then with the extra sleep and VitaminC, it will pass in a day instead of develop into a full blown illness.

When my kids were little, they caught something about once every other month. Now that they are teens, once or twice a year.

Incubation periods are different for every infection. Some are as short as a few hours, others are as long as 10-14 days.

How long an infection takes to run it's course also varies. Some as little as 24 hours, others for months.

Contagion is also different with every illness. Some are infectious only PRIOR to symptoms developing, others are only infectious AFTER onset of the first symptom. Some are still contagious 72 hours after the cessation of symptoms (although by the 24-72 hour after all symptoms are gone, most aren't). And more fun, some are asymptomatic.

But just for 'rule of thumb' sake... go by symptoms, and wait 24 hours after the last symptom. Colds and Flus typically last 7-10 days, and are contagious for the entire period.

In our generation, most people don't wait until their kids are well to bring them out in public (a whole host of reasons form the foundation: ridiculously strict attendence policies at schools and dual income families and vaccinations which have removed the fear of lethal illness, form the bulk of them). Since "everyone else" is just bringing their sick kids around infecting everyone else with callous disregard for other people, it's become the norm. Of course, because of this, our kids are staying sicker and getting more illnesses now than at any point in recorded history. Even just ONE generation ago 'cold and flu season' usually meant getting sick ONCE. Now, most kids are sick off and on for months. When we rest, our immune systems kick butt... when we're active, our immune system shuts off (the immune/adrenal response... it's an either/or scenario).

Incubation periods for most things are a week to 10 days. Sometimes, the time is less depending on the immune system of the receiver and the strength of the bacteria or virus.
LBC

It probably depends on the virus. It's best to talk to your pediatrician or google the specific virus.

It takes about three days after contact to come down with a cold.

Are your children in school? It could be from there. The incubation period depends on what virus/bacteria it is. Also because of the time of the year if the only symptom is runny nose it could be allergies.

Under the age 5 it's as high as 10 times per year. That depends on you of course. The more you take them out, the more you invite people over, the more they will be sick. But keep in mind that even if you are a stay at home mom, shop only at night when dad watches them, you and husband are still coming and going and bringing germs back.

Over the age 5, they slow down and eventually they just about never get sick. My 10 year old gets colds that are so mild that I can't tell unless she tells me. My oldest daughters were the same.

Time... anything as little as 24 hours to 2 weeks. It depends on the virus and the immune system of the child.

Runny noses don't always signal a cold. It could be allergies. It could be the weather. For instance, it's so windy here today that when I went outside just for a few minutes, my nose was running like a faucet. Also, in very cold, dry weather, your nose can start running more.
People are exposed to germs every day and there's not getting away from it. The main prevention for keeping from getting a bug of some sort is to keep your hands washed and not rub your eyes if you're around someone else who is sick.
I work at a hospital and am around sick people all the time. You'd be amazed how seldom doctors and nurses actually get sick because they keep their hands clean.
This is a tough time of year weather wise so it's hard to know if a runny nose is a signal of anything more than a runny nose.
Make sure the kids get plenty of rest and vitamin C.

Best wishes.

It all depends on the bug they've been exposed to. There're different incubation periods for everything.