Influenza or cold symptoms
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Understanding Influenza and Common Cold Symptoms
Overview of Influenza and Common Cold Symptoms
Both influenza (flu) and the common cold are respiratory illnesses caused by different viruses. The flu is caused by the influenza virus, while the common cold is typically caused by rhinoviruses, coronaviruses, or adenoviruses4 6 7. Despite their different viral origins, these illnesses share many overlapping symptoms, making it challenging to distinguish between them based on symptoms alone4 6 7.
Key Symptoms of Influenza
Fever and Body Aches
Influenza is generally more severe than the common cold. It often presents with high fever, body aches, and extreme tiredness. These symptoms are more intense and sudden in onset compared to those of the common cold4 6 7. Fever is particularly notable, with temperatures often exceeding 39°C7.
Dry Cough and Headache
A dry cough and headache are also common in influenza. These symptoms are more frequent and severe in flu cases compared to the common cold4 6 7. The presence of these symptoms, along with fever and body aches, can help differentiate influenza from milder respiratory infections.
Key Symptoms of the Common Cold
Runny or Stuffy Nose
The common cold is usually milder than the flu. People with colds are more likely to experience a runny or stuffy nose, which is less common in influenza4 6 7. This symptom is a key indicator that can help distinguish a cold from the flu.
Sore Throat and Sneezing
Sore throat and sneezing are also more prevalent in the common cold. These symptoms are typically less severe and less frequent in influenza cases4 6 7. The presence of these symptoms, along with a runny or stuffy nose, suggests a common cold rather than the flu.
Comparative Analysis of Symptoms
Frequency and Intensity
A systematic review comparing COVID-19, SARS, influenza, and the common cold found that cough, fever, muscular pain, and headache are common in both influenza and the common cold, but they occur at different frequencies and intensities. For instance, fever is more frequent in influenza (68%) compared to the common cold (40%)3. Similarly, headache, rhinorrhea, muscular pain, and sore throat are more common in the common cold than in influenza3.
Diurnal Variation
Research on diurnal variation in symptoms has shown that nasal secretion is greatest in the morning and decreases throughout the day, with a slight increase in the late evening. This pattern is observed in both colds and influenza, although influenza also causes an increase in average body temperature and drowsiness10.
Probiotic Effects on Symptom Incidence and Duration
A study on the effects of probiotics on cold and influenza-like symptoms in children found that daily dietary probiotic supplementation significantly reduced the incidence and duration of fever, coughing, and rhinorrhea. This suggests that probiotics could be a beneficial preventive measure for reducing the severity and duration of these symptoms in young children2.
Conclusion
While influenza and the common cold share many symptoms, they can often be distinguished by the severity and specific nature of these symptoms. Influenza typically presents with more severe symptoms such as high fever, body aches, and extreme tiredness, whereas the common cold is characterized by milder symptoms like a runny or stuffy nose, sore throat, and sneezing. Understanding these differences can aid in more accurate self-diagnosis and appropriate treatment.
Sources and full results
Most relevant research papers on this topic
Understanding the symptoms of the common cold and influenza
New knowledge of cytokines helps explain some previously folkloric symptoms of colds and flu, improving our understanding of their mechanisms.
Highly CitedProbiotic Effects on Cold and Influenza-Like Symptom Incidence and Duration in Children
Daily dietary probiotic supplementation for 6 months effectively reduces fever, rhinorrhea, and cough incidence and duration, antibiotic prescription incidence, and missed school days in children aged 3 to 5 years.
RCT
Large Human TrialHighly CitedComparison of the clinical differences between COVID-19, SARS, influenza, and the common cold: A systematic literature review.
A greater number of general symptoms should lead to a diagnosis of influenza or common cold rather than COVID-19.
Systematic ReviewThe common cold and influenza : colds & flu
The common cold is milder and more likely to cause runny or stuffy noses, while the flu is more severe and has more intense symptoms like fever, body aches, extreme tiredness, and dry cough.
Mechanisms of symptoms of common cold and flu
Common cold and flu symptoms are primarily caused by local inflammation of the airway and systemic release of cytokines from leukocytes.
The common cold and influenza
The common cold is milder and more likely to cause a runny or stuffy nose, while the flu is more severe and has more common and intense symptoms.
Colds and flu – an overview of the management
Colds and flu are caused by different viruses, and symptomatic treatment mainly involves over-the-counter medicines, antivirals, and herbal treatments.
CPD: Over the counter: Colds and influenza
Pharmacists can help individuals manage their symptoms and provide education to minimize the spread of cold and influenza, benefiting all ages.
Diurnal variation in the symptoms of colds and influenza.
Nasal secretion and temperature increase in colds and influenza B illnesses show diurnal variation, with greater nasal secretion and temperature in the early morning.
Non-RCT