How Many Infections in a Child is "Normal" Per Year?

Kids get a lot of infections... but at what point should a parent be concerned on how often these infections occur, particularly upper respiratory infections?

A German study went about to determine the answer to just that question... They prospectively followed 760 children born in 1990 and followed them for 12 years. Parents recorded the child’s illnesses in a diary and answered structured questions yearly up to age 12.

This is what they found... The mean number of infections per year for each age group (standard deviation):

• 0-2 years: 3.4 episodes (3.7) per year
• 3-5 years: 2.3 episodes (2.6) per year
• 6-12 years: 1.1 episodes (1.2) per year

Two standard deviations above the mean can be still considered within normal limits, though on the high side of normal:

• 0-2 years: 11 episodes per year

• 3-5 years: 8 episodes per year

• 6-12 years: 4 episodes per year

If a child gets more than this number of infections per year, one may need to consider possible immunodeficiency.

Source:

History of respiratory infections in the first 12 yr among children from a birth cohort. Pediatric Allergy and Immunology. Volume 19, Issue 6, pages 505–512, September 2008.

How many respiratory infections in children are "normal" per year? Allergy Notes by Dr. Ves.