How do cold and flu affect the body?

Usually, the first effect of influenza on the body is a fever with chills and muscle aches. You may also have a fever, fatigue and a headache. Remember, the flu is caused by a group of viruses that infect the respiratory system. As a result, effects on the body often focus on the throat, nose, and lungs. The nose may become congested or runny, the throat may become sore, and a cough may move from dry to wet as the virus runs its course.

The common cold primarily produces sneezing, nasal congestion, runny nose, and a sore throat. Other symptoms, such as fatigue, headache, and fever, may be mild or not occur at all.

Stacy Wiegman, PharmD
Pharmacy Specialist

Both the common cold and influenza, known as the flu, are viral illnesses that attack your body's respiratory system. Many different viruses cause colds, while fewer cause the flu.

When you have either a cold or the flu, you're likely to have a stuffy nose, fatigue, and a cough. But colds have certain symptoms that the flu typically doesn't, and vice versa. One key difference is fever: You may have a low-grade fever with a cold (below 102 degrees Fahrenheit), but higher fevers tend to go along with the flu. The flu is also likely to cause chills and sweats, nausea, headaches, severe body aches, and loss of appetite, which are much less common with the common cold.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.