Observational Research in Childhood Infectious Diseases (ORChID): a dynamic birth cohort study

Lambert, Stephen Bernard; Ware, Robert S; Cook, Anne L; Maguire, Frances A; Whiley, David M; Bialasiewicz, Seweryn; Mackay, Ian M; Wang, David; Sloots, Theo P; Nissen, Michael D; Grimwood, Keith

The highest incidence rates of acute respiratory infections (ARI) are during the first two years of life where on average infants experience six to eight ARIs each year. 20 Complication rates from acute otitis media (30%) and sinusitis (8%) are also highest in this age group, 21 while three to five per cent of all infants are hospitalised for viral lower respiratory tract infections, including bronchiolitis, pneumonia, croup, and secondary bacterial pneumonia. 22 There is emerging evidence that infectious insults to the growing and developing lung during early childhood contribute to the pathogenesis of chronic pulmonary disorders in older children and adulthood, such as asthma, 23 chronic obstructive 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 F o r p e e r r e v i e w o n l y page 7 of 33 pulmonary disease, 24 25 and bronchiectasis. 26 Young children are often household introducers, actively transmitting respiratory infections to other family members. 27 Taken together, ARIs in children result in enormous current and future costs to the healthcare system, families and society. 14 Likewise, acute gastroenteritis (AGE) is still a major cause of childhood morbidity in high-income