How long does the common cold last?
January 14, 2019
A common question that carries much controversy, even from my colleagues.
In a literature review published in the British Medical Journal, Dr. Thomson discussed the natural course of upper respiratory infections in children. They identified the mean number of days when symptoms had resolved in 50% of children and at the 90% threshold on no anti viral medicine.
It takes 25 days for >90% of the children to be symptom free from acute cough. The CDC has this statistic at 10-14 days. Sore throat resolved in 2-7 days while the CDC has this at 7-14 days. Congestion resolved in 15 days.
Bronchiolitis, wheezing and viral lung inflammation, resolved in 21 days.
In present day pediatric medicine, we are aggressively trying to limit antibiotic use. This study may help parents feel comfortable with watchful waiting as their child works through the average upper respiratory illness.
As a pediatric group, we generally recommend parents bring their children in for an evaluation when the following events occur at any time:
1) High and unremitting fever. Generally, greater than 102 degrees F and for more than 3 to 4 days.
2) Excessive fatigue or listless appearance.
3) 10 - 14 days of cough and congestion associated with a lack of appetite, recurrent headaches, sinus pressure, fever > 100.5 F or fatigue.
4) A rapid respiratory rate that does not fall when the fever abates. This is a cardinal sign of pneumonia.
5) Exposure to a child with known infection from pertussis, flu or any severe communicable disease.
As always, call your local provider if your child's symptoms concern you in any way. Keep this list in mind when deciding on the right course of action for your child.
Part 2: What is the deal with fever? I am getting lots of questions about fever again. I am hearing about significant misinformation being dispensed at emergency rooms and urgent cares.
Fever - the dreaded word that makes many a mother panic. When to worry is the question?
Fever is the body's natural response to an infection and is critically important in helping the body rid itself of the virus or bacterium. Warm blooded mammals have developed the ability to raise their core body temperature in times of infectious stress in an effort to kill the infectious organism by making the host environment inhospitable through heat and also by activating the immune system.
Fever is produced when the brain's thermostat called the hypothalamus tells the body to increase the core temperature. This is achieved by releasing heat from brown adipose fat and muscle movement like shivering coupled with peripheral blood vessel constriction which keeps warm blood centrally in the core. Producing a fever comes at a great metabolic cost and is unlikely to be an evolutionary mistake.
In a nice article by Dr. Gonzalez Piaza, we see a tour through the research on fever. As quoted, "have found that suppression of fever in normal clinical settings can potentially lead to negative effects at the population-level, due to a possible increase in the spread of associated infections."
Fever is known to help shorten the length of an infectious illness. I reserve treatment of fever when my child is miserable which usually occurs around 103-104 degrees Fahrenheit. Even at 103F, if he or she is not miserable, I will let it burn helping to kill the infection. Super high fever, greater than 104F, is a marker of a potentially serious infection or cancer and requires medical evaluation immediately.
Myth - infectious fevers can cause brain damage.
The body will naturally reduce fever through sweating and blood vessel dilation when it decides that the temperature needs to go down. Hyperpyrexia, high fever, that causes brain damage is generally thought to only occur in normal individuals when they are exposed to a hot environment like a closed car in the summer where the body cannot reduce the core temperature through normal means. Infections that a typical child will contract do not cause hyperpyrexia.
Treatment is usually with cool compresses on the forehead and armpits or medically with ibuprofen. I do not recommend the recurrent use of Tylenol/acetaminophen because of recent research showing adverse effects on different humans systems especially in pregnant women. Aspirin is not recommended for children under 12 years of age because of the rare case of liver disease that occurs when the flu is treated with aspirin.
My take home point today: Think of fever as a friend in the fight against infection. Read below if you want more details.
Thomson British Medical Journal Article
Piaza Intractable Rare Diseases Research Article
Nalin Scientific American Article
Mayo Clinic Fever Article
Evans Nature Reviews Immunology Article
Seattle Children's Hospital Fever Article