An investigation of the family background of acute haemophilus infections of children

Abstract

SUMMARYNose and throat swabs, for culture of Haemophilus influenzae type b, and blood samples, for measurement of antibodies specific for that serotype, were collected from members of 28 families from which children had been admitted to hospital with acute H. influenzae type b infections (mainly meningitis or epiglottitis). The patients with meningitis were younger than those with epiglottitis and had more siblings, with a marked predominance of sisters. Investigations within a few days of admission of the affected children to hospital detected carriers of H. influenzae type b (19 altogether) in 13 of the 28 families, including 9 of the 13 families with 3 or more children. Members with raised antibody titres for H. influenzae type b (suggesting the presence of the organism for at least a few weeks) were found in 17 of the 25 families from which blood samples were obtained, including all 11 families with 3 or more children. Most of the patients probably acquired their infections from within their own families, and siblings under 11 years old were of predominant importance both as carriers and as potential sources of the patients' infections. Persistence of the organism within families for up to 6 months was demonstrated. Possible reasons for the difference in age-incidence between haemophilus meningitis and epiglottitis and for the occurrence of the former in babies with older sisters are suggested, and also a possible connexion between the results of this survey and the likely value of immunization against H. influenzae type b.

Nasopharyngeal carriage and antibiotic resistance ofHaemophilus influenzaein healthy children

“…Gwynedd is a rural county in North Wales with a low population density. It has previously been noted (Turk, 1975) (Philpott-Howard & Williams, 1982), of which a large percentage of strains would have been derived from hospital patients. Ampicillin resistance was present in 5-4 % of strains compared with 6-2 % (5-8 % ,1-lactamase positive) in the UK study, tetracycline 1P3 % compared with 31 %, chloramphenicol 13 % compared with 1X03 % and sulphamethoxazole 0% compared with 1P5%.…”

Mathematical models of Haemophilus influenzae type b

“…The approach adopted was to add sophistication to the model only if it were necessary to explain the data sets. For example, as discussed above, Hib transmission is thought to be greater within families whose members have experienced Hib disease [27,48,49]. Nevertheless, for modelling purposes, the numbers of diseased individuals were assumed too small to significantly affect the infectious process in the general population.…”

Occurrence of HLA Types in H. Influenzae Type B Disease

“…He feels that the passage of the organism through one or two partially immune contacts is necessary before the bacterium becomes invasive. An increased number of older siblings under 11 years of age were also recorded by Turk (1975) in a study of 14 children with H. influenzae meningitis. Our study did not reveal any significant difference between the mean number of siblings in the two groups to account for the invasive disease in Group A patients.…”