Early symptoms of influenza


This is a tricky one, because even though among the early symptoms of influenza fever is one of the most prominent, not every person who has the flu necessarily feels feverish. That’s why it is important to pay attention to other possible symptoms. Fortunately, all types of influenza have a similar set of symptoms. Moreover, they should be easy to recognize because they resemble those of the common cold, albeit more severe. It should also be fairly simple to tell a cold from the flu, since the former develops slowly, while the latter comes on suddenly.

The early signs of influenza include:

·         A 100˚F (38˚C) or higher fever.

·         Cough.

·         Sore throat.

·         Running or stuffed nose.

·         Headache.

·         Body aches.

·         Chills.

·         Tiredness.

·         Nausea


Most commonly in children

·         Vomiting

·         Diarrhea


In addition to keeping an eye out for the symptoms of influenza, a flu test is another method to find out whether or not you have the flu. The FDA has approved more than 10 rapid influenza diagnostic tests. Some of can identify and distinguish between A and B influenza viruses, while others can identify but not distinguish them. Either way, most take between 10 and 15 minutes to show results.


Types detected

Time (minutes)


A & B


Alere Influenza

A & B


BD Veritor System

A & B



A & B



A & B



A & B



A & B



A or B


QuickVue A+B

A & B


SAS FluAlert A&B

A & B


SAS FluAlert A



SAS FluAlert B




A & B



A & B



A & B


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Despite of the quickness with which these tests can determine if you have influenza, they have a tendency of yielding false positives or false negatives depending on the flu prevalence in your community. Therefore, at the beginning of the flu season you may test positive for influenza and not have it, and at the height of the season you may test negative even if you do have the flu.

In light of this, there are flu tests that take more time and must be conducted in special labs, but which provide more precise and sensitive results. Such tests include:


Types detected


Viral cell culture

A & B

3 to 10 days

Rapid cell culture

A & B

1 to 3 days

Immunofluorescence, Direct (DFA) or Indirect (IFA) Antibody Staining

A & B

1 to 4 hours

RT-PCR4 (singleplex and multiplex; real-time and other RNA-based) and other molecular assays

A & B

1 to 6 hours


Most people will be able to make it through a bout of the flu with rest, lots of fluids, and maybe flu medications. However, you should see a doctor if the early symptoms of influenza come back with fever and worsening cough. Also seek medical care if you experience one or more of these signs:

·         Difficulty breathing.

·         Shortness of breath.

·         Lips turning purple or blue.

·         Chest or abdomen pain or pressure.

·         Sudden dizziness.

·         Confusion.

·         Severe vomiting.

·         Seizures.

Children younger than 5 years of age, adults 65 and older, and pregnant women are high risk of suffering the serious consequences of the flu, as are people with the following conditions:

·         Asthma.

·         Neurological and neurodevelopmental conditions.

-        Cerebral palsy

-        Epilepsy

-        Stroke

-        Intellectual disability

-        Developmental delay

-        Muscular dystrophy

-        Spinal cord injury

·         Chronic lung disease.

-        COPD

-        Cystic fibrosis

·         Heart disease.

·         Endocrine disorders.

·         Kidney disease.

·         Liver disease.

·         Metabolic disorders.

·         Immune systems weakened by illness or medication.

-        HIV or AIDS

-        Cancer

-        Taking chronic steroids

·         Body mass index of 40 or higher.

 However, even healthy people in the prime of their lives are susceptible to potentially life-threatening complications of influenza such as:

·         Pneumonia

·         Bronchitis

·         Sinus and ear infections

So prevent yourself from contracting the flu and spreading it to others by washing your hands regularly with soap and water, covering your mouth when coughing or sneezing, refraining from touching your eyes, nose and mouth, avoiding crowds and contact with sick people (or with healthy people if you’re the one who’s sick), exercising, eating and sleeping well, and above all things, getting your seasonal flu vaccine as soon as you can.