Differential Diagnosis of Flu
Differential Diagnosis for Flu
Know the Difference for Best Treatment
Colds and flu are caused by different viruses. “As a rule of thumb, the symptoms associated with the flu are more severe,” says Hauguel. Both illnesses can lead to a runny, stuffy nose; congestion; cough; and sore throat. But the flu can also cause high fever that lasts for 3-4 days, along with a headache, fatigue, and general aches and pain. These symptoms are less common when you have a cold.
Source: NIH News in Health (NIH)1
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Back to: « Flu
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Airborne Allergies: “Allergies are a little different, because they aren’t caused by a virus,” Hauguel explains. “Instead, it’s your body’s immune system reacting to a trigger, or allergen, which is something you’re allergic to.” If you have allergies and breathe in things like pollen or pet dander, the immune cells in your nose and airways may overreact to these harmless substances. Your delicate respiratory tissues may then swell, and your nose may become stuffed up or runny.
Treatment depends on which you have. A health professional can help you choose the best therapy.
- Symptoms last up to 2 weeks
- Stuffy, runny nose; sore throat; cough
- Treated with rest, fluids, over-the-counter (OTC) medicines to ease symptoms
- Symptoms usually last 1-2 weeks
- High fever (100-102 °F, or higher in youngsters), headache, aches and pains, weakness, exhaustion, cough, chest discomfort
- Treated with rest, fluids, OTC medicines, prescription antiviral drugs
- Lasts as long as allergens (such as pollen, pet dander) are present
- Stuffy, runny nose; itchy, watery eyes
- Treated with antihistamines, decongestants, nasal steroids
Source: NIH News in Health (NIH)3
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Food Poisoning: A sick feeling washes over you: nausea, stomach cramps, headache and fever. Vomiting and diarrhea may soon follow. The symptoms are familiar to anyone who’s had the flu, but there may be another culprit—food that’s gone bad.
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Toxoplasmosis: Some people who have toxoplasmosis may feel as if they have the "flu" with swollen lymph glands or muscle aches and pains that last for a month or more.
Source: CDC Parasites7
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Trichinellosis: Many mild cases of trichinellosis are never specifically diagnosed because they are assumed to be the flu or other common illnesses.
Source: CDC Parasites8
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Common Cold: Flu is not the same as a common cold, and can be a serious illness. For some people, such as the elderly and those with underlying medical conditions, the flu can cause serious complications which require hospitalisation. It can sometimes lead to death.
Cold and flu symptoms are similar but flu tends to be more severe.
Cold -- Flu
Appears gradually -- Appears quickly within a few hours
Affects mainly your nose and throat -- Affects more than just your nose and throat
Makes you feel unwell but you’re okay to carry on as normal - for example, go to work -- Makes you feel exhausted and too unwell to carry on as normal
Source: NHS Choices UK11
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Japanese encephalitis: Most people infected by the Japanese encephalitis virus have either no symptoms, or mild, short-lived symptoms, which are often mistaken for flu.
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- Source: NIH News in Health (NIH): newsinhealth.nih.gov/ issue/ oct2014/ feature2
- Source: NIH News in Health (NIH): newsinhealth.nih.gov/ 2007/ February/ docs/ 01features_02.htm
- Source: CDC Yellow Book 2016: cdc.gov/ travel/ yellowbook/ 2016/ infectious-diseases-related-to-travel/ toxoplasmosis
- Source: CDC: cdc.gov/ fungal/ index.html
- Source: CDC Parasites: cdc.gov/ parasites/ toxoplasmosis/ gen_info/ faqs.html
- Source: CDC Parasites: cdc.gov/ parasites/ trichinellosis/ disease.html
- Source: Queensland Health: conditions.health.qld.gov.au/ HealthCondition/ condition/ 8/ 118/ 82/ influenza-the-flu
- Source: New Zealand Health: health.govt.nz/ your-health/ conditions-and-treatments/ diseases-and-illnesses/ influenza
- Source: NHS Choices UK: nhs.uk/ conditions/ common-cold/
- Source: NHS Choices UK: nhs.uk/ conditions/ japanese-encephalitis/
- Source: NHS Choices UK: nhs.uk/ conditions/ Lyme-disease/
- Source: NHS Choices UK: nhs.uk/ conditions/ tick-borne-encephalitis/
- Source: GOV.UK: gov.uk/ guidance/ swine-influenza
- Source: GOV.UK: gov.uk/ government/ collections/ carbon-monoxide-co
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Note: This site is for informational purposes only and is not medical advice. See your doctor or other qualified medical professional for all your medical needs.