The problem

In the course of a year, individuals in the United States suffer 1 billion colds, according to some estimates. Colds are most prevalent among children, and seem to be related to youngsters' relative lack of resistance to infection and to contacts with other children in day-care 

centers and schools. Children have about six to ten colds a year. In families with children in school, the number of colds per child can be as high as 12 a year.

In the course of a year, individuals in the United States suffer 1 billion colds, according to some estimates. Colds are most prevalent among children, and seem to be related to youngsters' relative lack of resistance to infection and to contacts with other children in day-care 

centers and schools. Children have about six to ten colds a year. In families with children in school, the number of colds per child can be as high as 12 a year. Adults average about two to four colds a year, although the range varies widely. Women, especially those

In the course of a year, individuals in the United States suffer 1 billion colds, according to some estimates. Colds are most prevalent among children, and seem to be related to youngsters' relative lack of resistance to infection and to contacts with other children in day-care 

centers and schools. Children have about six to ten colds a year. In families with children in school, the number of colds per child can be as high as 12 a year. Adults average about two

In the course of a year, individuals in the United States suffer 1 billion colds, according to some estimates. Colds are most prevalent among children, and seem to be related to youngsters' relative lack of resistance to infection and to contacts with other children in day-care centers and schools. Children have about six to ten colds a year. In families with children in school, the number of colds per child can be as high as 12 a year. Adults average about two to four colds a year, although the range varies widely. Women, especially those

Introduction

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