Search

A total of 5217 middle ear fluid (MEF) samples obtained from 1203 children with otitis media, aged 3 months to 6 years, were studied for the presence of Branhamella catarrhalis (Br) between Oct. 1977 and Sept. 1981. Br grew in 10.2% of 3497 MEFs of acute otitis media (AOM), with almost the same frequency in the very first and subsequent attacks. During the first 4 years of life the percentage did not vary much; among older children it seemed to decrease. The overall prevalence of Br in AOM did not change during the study period. Br alone grew in 72.4% of acute MEFs with Br; with other bacteria the respective figure was 82.9% (p less than 0.001). Acute attacks with bilateral Br were found in 22.8% of attacks with Br. In 1720 non-acute MEFs obtained at postacute control visits, Br was isolated in only 7.0%. The proportion of beta-lactamase-producing strains among the 2419 otitis-Br strains tested in two laboratories of the two study regions showed an increase from 27.1% and 21.1% in 1980 to 57.6% and 38.6% in 1983, respectively (p less than 0.001).

The occurrence of acute otitis media was studied over a one-year period in a total population of 146822 persons living in different parts of Finland. Of these 146822 persons, 4583 experienced a total of 6518 otitis attacks giving an annual incidence rate of 4.44% (4.48% in males and 4.07% in females, P less than 0.001). Acute otitis media was strikingly concentrated in the youngest age groups, with the highest annual incidence rates, in the order of 50%, found in infants younger than 2 years. Half of all the episodes occurred before the age of 33 months. The relative risk of getting acute otitis media was about 200 times higher during the first 2 years of life than as an adult. The occurrence of otitic episodes followed seasonal variations, and in urban areas the incidence was significantly (P less than 0.001) higher than in the countryside.

A multivariant modelling method was used to analyse the risk, associated with 22 different factors, of contracting acute otitis media (AOM) in a prospective cohort of 1294 urban children followed up to the age of 17–32 (mean 25) months. By far the most important risk factor was the caring of the child at a day-care centre. The importance of this factor further increased with increasing recurrence of the attacks. Next in order came the existence of sibling(s) with AOM attacks during the follow-up. Prolongation of breastfeeding increased the protection against AOM during the first year of life. The frequency of AOM attacks was lowest around midsummer and highest in early winter.

The factors affecting the occurrence and recurrence of acute otitis media (AOM) were studied among 471 2-3-year-old children in two cities in Finland. Of these children, 188 had experienced greater than or equal to 3 attacks of AOM, 76 had had 1-2 attacks and 207 no otitis attacks (= control group). The study showed that the risk of recurrent AOM was increased among those children attending day-care nurseries as well as among those who had several siblings. Proneness to rhinorrhea and exposure to passive smoking at home was associated with an increased risk of AOM, while prolonged breast-feeding (greater than 6 months) seemed to reduce it. No correlation was found between the risk of recurrent AOM and the place of residence or type of housing, the parental otitis history, or atopic diathesis of a child. Thus the study suggested that to protect a young child from AOM we should promote breast-feeding and home-care for babies as well as avoid smoking in the home.