Lately, I’ve been asked many questions regarding the differences and similarities between the common cold, seasonal flu, swine flu and avian flu. Hopefully, the information below can shed some light.

Virus	The Common Cold	Seasonal Flu	Swine Flu	Avian Flu (bird flu)
Type of Virus	Most common: rhinovirus, coronovirus Less common: adenovirus and enterovirus	Influenza A, B and C	Influenza A H1N1	Influenza A H5N1
Transmission	human to human through coughing or sneezing by infected person(s) or from touching contaminated surfaces or objects and later touching mouth, nose and eyes	human to human through coughing or sneezing by infected person(s) or from touching contaminated surfaces or objects and later touching mouth, nose and eyes	human to human through coughing or sneezing by infected person(s) or from touching contaminated surfaces or objects and later touching mouth, nose and eyes	virus mainly spread among birds or occurs in humans who are in direct or close contact with H5N1 infected birds or contaminated surfaces. However, there are cases where the virus was transmitted from human to human
Symptoms	Mild	Mild to Severe	Mild to Severe	Severe
Fever and Chills	Uncommon	Common; very sudden	Common; very sudden	Common; very sudden
Headache	Uncommon	Common	Common	Common
Aches and Pain	Mild	Common	Common	Common
Fatigue and weakness	Mild	Common	Common	Common
Runny nose	Common	Common	Common	Common
Stuffy nose	Common	Uncommon	Uncommon	Uncommon
Cough	Initially dry and then becomes wet (mucus or phlegm production)	Dry	Dry	Dry
Sore Throat	Common	Sometimes	Sometimes	Sometimes
Other symptoms			Nausea, vomiting and diarrhea	Nausea, vomiting and diarrhea

Please seek medical attention immediately if you experience any of the following symptoms:

• chest and/or stomach pain, wheezing, shortness of breath (difficulty breathing or fast breathing)
• fever: > 38.5C (101.3F) for more than 24 hours; or children with fever > 39C (102.2F).
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• fever with rash
• severe or persistent vomiting
• severe sore throat
• severe headache or neck pain
• severe earache
• low appetite or fluid intake
• signs of dehydration: dizziness, light-headed, thirsty, low urine output, Children: sunken eyes, grayish skin, low urine output
• confusion
• seizures
• loss of consciousness
• bluish skin
• bloody or colored phlegm (mucus)
• fever and cough returns (may be worse than before)

The following population are more at risks of complications if infected by seasonal flu therefore they should take more precaution:

• adults over the age of 65,
• pregnant female,
• individuals with the following conditions such as diabetes, heart or lung condition, kidney disease, cancer, low immune system or on immune-suppressing medication, blood disorder (sickle cell anemia)
• Note: Swine flu affects more individuals below the age of 25, especially below 5 years, rather than those above the age of 64 like the regular seasonal flu (about 1/3 may have antibodies against virus but levels may not be adequate for protection)
• Note: Avian flu mostly affects birds but there are a few cases where people whom have direct or close contact with H5N1 infected birds or contaminated surface were infected. Therefore, those who have close contact with birds such as poultry workers should follow proper hand hygiene care and wear protective equipment.

For next post, I will discuss ways to prevent, relieve symptoms or shorten duration of cold and flu infection