Person to Person
The main way that influenza viruses are thought to spread is from person to
person in respiratory droplets of coughs and sneezes. (This is called "droplet
spread.") This can happen when droplets from a cough or sneeze of an infected
person are propelled through the air and deposited on the mouth or nose of
people nearby. Influenza viruses may also be spread when a person touches
respiratory droplets on another person or an object and then touches their own
mouth or nose (or...
Colds usually begin abruptly with a sore throat followed by these common cold symptoms:
Clear, watery nasal drainage
Usually, there is no fever with the common cold. In fact, fever and more severe symptoms may indicate that you have the flu or a bacteria infection and not a cold.
For the first few days of a cold, your nose drips with watery nasal secretions. Later, these secretions may become thicker and darker.
A mild cough is a common cold symptom and may last into the second week of your cold. If you have asthma or other lung problem, a cold may make it worse. Talk to your health care provider to see if you need to modify your asthma treatment plan or need additional treatment.
If you are coughing up thick or dark mucus or you have a fever, you may have a bacterial infection. Seek care from your health care provider. Also, call your health care provider if your cough doesn't improve after a few weeks.
Common cold symptoms usually start between one and three days after you are infected by a cold virus. Typically, they last for about three to seven days. At that point, the worst is over, but you may feel congested for a week or more. During the first three days that you have cold symptoms, you are most contagious; however, colds are often contagious through the first week. This means you can pass the cold virus to those you come in contact with.
Is It Allergies Instead of a Cold?
Sometimes you might mistake symptoms of the common cold for allergic rhinitis, also known as hay fever. If your cold symptoms begin quickly and are over within one to two weeks, chances are it's a cold and not an allergy. If the symptoms last longer than two weeks, check with your health care provider to see if you've developed an allergy.
Allergies are caused by an overactive immune system. For some reason, your body overreacts to substances such as dust or pollen. It then releases chemicals such as histamine. This can cause swelling in your nasal passages, a runny nose, coughing, and sneezing. Allergies are not contagious, although some people may inherit a tendency to develop them.