Effect of TMP-SMX on nasopharyngeal carriage of ampicillin-sensitive and ampicillin-resistant Hemophilus influenzae type B

Global Genetic Structure and Molecular Epidemiology of Encapsulated Haemophilus influenzae

“…Strains of type b occur mainly in children from birth to 10 years of age, in whom there is only generally (at most) a 5070 colonization frequency of the throats of healthy individuals not associated with individuals with type b disease [96][97][98][99]. (The carriage rate for type b organisms may be much higher in contacts of children with invasive disease [45,[100][101][102].) Serotype b strains are even rarer in infants (1% colonization) and in healthy adults «1% colonization).…”

Elaboration of type b capsule by Haemophilus influenzae as a determinant of pathogenicity and impaired killing by trimethoprim-sulfamethoxazole.

“…INTRODUCTION Haemophilus influenzae type b (Hib)' is a major pathogen of infancy and childhood resulting in bloodstream infections associated with serious complications such as meningitis. In recent years, attention has been focused on the occurrence of secondary cases of invasive Hib infections in households or day-care centers where susceptible young children are in intimate contact and at high risk of developing invasive disease (1)(2)(3)(4)(5). Efforts to interrupt person-to-person spread of Hib in these settings have included the use of antibiotics such as trimethoprim-sulfamethoxazole (TMP/ SMZ) (1,3,7), rifampin, (6)(7)(8), cefaclor (9,10), and ampicillin (11)(12)(13).…”

“…In recent years, attention has been focused on the occurrence of secondary cases of invasive Hib infections in households or day-care centers where susceptible young children are in intimate contact and at high risk of developing invasive disease (1)(2)(3)(4)(5). Efforts to interrupt person-to-person spread of Hib in these settings have included the use of antibiotics such as trimethoprim-sulfamethoxazole (TMP/ SMZ) (1,3,7), rifampin, (6)(7)(8), cefaclor (9,10), and ampicillin (11)(12)(13). During an outbreak of Hib carriage and disease in a chronic disease hospital (3), TMP/ SMZ failed to eradicate nasopharyngeal carriage in 30% of carriers, although the minimal inhibitory concentration (MIC) of TMP/SMZ for these H. influenzae (Hi) strains indicated that they were susceptible.…”

Effect of antibiotics on adherence of Haemophilus influenzae type b

“…Attempts to prevent serious H. influenzae type b infections in children have included the use of antibiotics to eradicate nasopharyngeal colonization with this organism. Although a number of orally administered antibiotics, including ampicillin (1,4), cefaclor (7,21), trimethoprim-sulfamethoxazole (20), and erythromycin-sulfisoxazole (7), have failed to eradicate mucosal colonization, rifampin has been shown to be effective (5,7). Although H. influenzae type b is often cultured from the nasopharynges of children with serious systemic H. influenzae type b infections before the initiation of intravenous antibiotic therapy, the organism often is not isolated during therapy (2).…”