When are you Contagious with a Cold?

Colds are one of the most common illnesses worldwide. According to the Centers for Disease Control and Prevention (CDC), adults catch an average of 2-3 colds per year while children can catch up to 6-8 colds annually. With colds being so widespread, it’s important to understand when you are contagious to help prevent spreading illness.

What is a Cold?

A cold is a viral infection of the upper respiratory tract, including the nose, throat, sinuses, and upper airways. Colds are caused by over 200 different viruses, with rhinoviruses being the most common. Cold symptoms usually appear 1-3 days after catching the virus and can include:

• Runny or stuffed up nose
• Sore throat
• Coughing
• Sneezing
• Mild headache
• Mild body aches

Symptoms are usually mild and last for 7-10 days in healthy adults. Colds are generally harmless, although they can make you feel pretty lousy.

How are Colds Spread?

Colds easily spread from person to person through close contact. The cold virus is carried in droplets that are released when an infected person coughs, sneezes, or talks. You can catch a cold by:

• Breathing in these droplets directly from an infected person. This usually requires close contact within 3-6 feet.
• Touching surfaces like doorknobs, phones, or keyboards contaminated with the cold virus then touching your eyes, mouth, or nose before washing your hands.
• In rare cases, catching droplets from sneezes or coughs directly on your eyes or nostrils.

Once exposed, it takes about 1-3 days for cold symptoms to develop as the virus multiplies inside your body.

When are you Contagious?

You can spread your cold to others both before and during the time you have symptoms. However, you are likely the most contagious in the first 2-3 days after symptoms start.

This is because your viral load is highest at the beginning of infection. Even before symptoms appear, you can shed virus particles through coughing, sneezing, and close contact with others.

According to Harvard Health, you are contagious:

• 1 day before symptoms start – Viral load rapidly builds 24-48 hrs before symptoms appear.
• 1-2 days after symptoms start – This is when you feel sickest and are most contagious.
• Up to 7 days after symptoms start – You remain contagious the entire time you have symptoms.
• Possibly for weeks after symptoms stop – You can continue shedding some cold viruses for days or weeks after you start to feel better. But viral load greatly decreases making you much less contagious.

So when should you isolate to avoid spreading your cold to others? The safest bet is to isolate for at least 5 days from the start of symptoms until the worst has passed. Wearing a mask around others for the first 7-10 days can further reduce spread.

The exception is if you have a fever, which can extend your contagious period. Continue isolating until your fever resolves without the use of fever-reducers.

How Long do Cold Symptoms Last?

Cold symptoms usually last about 7-10 days but can linger for up to 2 weeks in some cases. Here is the typical symptom timeline:

• Days 1-3 – Symptoms start and worsen. Runny nose, sneezing, sore throat, coughing, congestion, fever, and body aches peak. This is when you are most contagious.
• Days 4-7 – Symptoms remain but start improving gradually. Coughing and congestion may persist. Fatigue sets in.
• Days 8-10 – Symptoms have mostly resolved besides lingering cough and small amounts of mucus. Viral load has greatly decreased so you are less contagious.
• Days 11-14 – Symptoms are mostly gone besides residual cough that may linger 1-2 weeks. You are likely no longer contagious if fever has resolved.

While most colds run their course in 7-14 days, a small percentage of people can have symptoms lasting over 2 weeks. See your doctor if your cold isn’t starting to improve after 10 days.

How to Avoid Spreading Your Cold

To avoid giving your cold to others:

• Stay home when sick, especially the first few days when symptoms are worst.
• Cover coughs and sneezes using a tissue or your elbow. Dispose of used tissues immediately.
• Wash hands frequently using soap and warm water.
• Avoid touching your face which can spread germs from your hands into your nasal passages, eyes, and mouth.
• Clean and disinfect surfaces like doorknobs, counters, keyboards, and phones.
• Avoid close contact and sharing items like drinks, utensils, and lip balm with others during your contagious period.
• Wear a mask when around others if you must go out when contagious.

Practicing good hygiene can help protect you and prevent the spread of colds in your home and community.

How to Feel Better if You Catch a Cold

While there is no cure for the common cold, you can find relief from symptoms:

• Get plenty of rest and sleep to help your body fight infection.
• Stay hydrated by drinking lots of water, broth, and caffeine-free beverages.
• Use a humidifier to ease congestion and sore throat.
• Take OTC medications like acetaminophen and ibuprofen to reduce fever and body aches. Avoid giving aspirin to children.
• Try honey or over-the-counter cough drops for soothing coughs.
• Inhale steam from a hot shower or pot of boiled water to relieve congestion.
• Gargle salt water to ease a sore throat.
• Eat chicken soup which may help reduce nasal congestion and coughing.

Talk to your doctor if symptoms don’t improve after 7-10 days or worsen at any time. Most colds resolve on their own without complications. Get plenty of rest and stay home while sick to protect others.

FAQs About Colds

Can you catch a cold from being cold or going outside with wet hair?

No, colds are caused by viruses, not from getting chilled or being cold. However, cold dry air may dry out and irritate nasal passages, leading to congestion.

What’s the difference between a cold and the flu?

Colds and flu share some similar symptoms but flu tends to be more severe. Flu brings fever, chills, body aches, headaches, and fatigue. Cold symptoms are generally milder with lower fevers.

Can antibiotics treat a cold?

No, antibiotics only work against bacterial infections and are ineffective for colds caused by viruses. Taking antibiotics unnecessarily can lead to antibiotic resistance down the road.

Are colds contagious through pool or hot tub water?

No, cold viruses are unlikely to spread through well-chlorinated pool or hot tub water. However, sharing glasses or utensils with a sick swimmer could pass the virus.

Can you catch a cold by going outside with wet hair?

No. This is a common myth. Colds are caused by contact with viruses, not by chilled or wet hair making you cold. However, wet hair can cause discomfort.