Do I have the flu, a cold, or allergies?

SOMETHING is making you sick and miserable. And unfortunately, this time of year, it could be any number of things.

While you may feel miserable regardless of the cause, identifying the problem could make a difference as to how to treat it and feel better sooner.

The difference between the flu, colds and allergies


Better known as the flu, influenza is the most serious of the cold-weather bugs that circulate this time of year. Flu season is already well underway in San Antonio, so residents need to be careful.

Symptoms of the flu include fever, headache, body aches, severe fatigue, chills, sore throat and a dry cough.

Influenza kills thousands of people each year in the U.S., results in hundreds of thousands admitted to hospitals and infects millions. This is because there are many complications that can arise from the flu.

The hardest hit are often young children, seniors, pregnant women or those with chronic illnesses. If you have difficulty breathing, a fever over 100.4°F or 38.0°C, chest or stomach pain, dizziness and confusion, or severe and persistent vomiting, you should consider seeking medical attention. Without the proper care and treatment, complications can worsen.

As always, the best way to prevent the flu is to get an influenza vaccine or flu shot every year. Even if the vaccine this year is not as effective, it will lessen the flu’s severity and keep you out of the hospital.


A long list of other respiratory viruses (rhinovirus, enterovirus, adenovirus, parainfluenza, and more) also circulate this time of year, and often wind up falling under the umbrella catchphrase of “colds.” Although some of these can be serious in children or patients with weakened immune systems, they are usually less severe for most people.

Symptoms for colds vary, but often include nasal symptoms like a runny nose and congestion, sneezing, coughing, and sore throat. Fever is also less common among cold symptoms.

Unlike the flu, these viruses rarely lead to severe complications and recovery is often quicker. While there is no vaccine, doctors do have some recommendations about making you feel better. Over-the-counter medications can help ease symptoms of a cold, along with plenty of rest and fluids.


Allergy symptoms occur when the body mistakes harmless substances like dust or pollen for germs and attacks them as an immune response, just as when fighting viruses or other pathogens. This causes your body to release substances such as histamine, which results in inflammation.

Symptoms of allergies usually include a runny nose, sneezing, itchy and watery eyes, coughing and fatigue.

Unlike colds or the flu, allergies are not contagious. They do tend to last longer, can make people feel miserable and may occur at any time of the year.

Unfortunately for San Antonio residents, the timing of “cedar fever,” an allergic reaction to the Mountain Cedar tree commonly found in South Texas, overlaps much of the cold and flu season.

A number of treatment options are available, including nasal rinses, antihistamines, decongestants, nasal steroids and even allergy shots.

What you can do to prevent the flu — and many other infections:

  • Get a flu shot if you haven’t already.
  • Wash your hands frequently – and teach your children to do the same.
  • Cover coughs and sneezes with the fold of your arm.
  • Stay home when you’re sick — a strategy called social distancing.

Crowds are common this time of year — whether it’s the shopping center or holiday parties. People tend to want to attend holiday gatherings with family and friends, even when they’re sick. They may feel guilty about staying away. But one of the best gifts you can give this holiday season is to protect others — by vaccinating yourself or by staying away if you’re sick. And if you’re hosting a gathering and have someone at risk at home, such as a young child or a family member on chemotherapy, give your guests permission to skip if they’re sick.

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