Impact of Bordetella pertussis exposures on a Massachusetts tertiary care medical system.

OBJECTIVE: To assess the impact of outbreaks of Bordetella pertussis infection on a tertiary care medical system. DESIGN: Retrospective study. SETTING: Academic tertiary care medical center and affiliated ambulatory care settings. SUBJECTS: All patients and healthcare workers (HCWs) who were in close contact with patients with laboratory-confirmed cases of B. pertussis infection from October 1, 2003, through September 30, 2004. INTERVENTION: Direct and indirect medical center costs were determined, including low and high estimates of time expended in the evaluation and management of exposed patients and HCWs during outbreak investigations of laboratory-confirmed cases of B. pertussis infection. RESULTS: During this period, 20 primary and 3 secondary laboratory-confirmed cases of B. pertussis infection occurred, with 2 primary pertussis cases and 1 secondary case occurring in HCWs. Outbreak investigations prompted screening of 353 medical center employees. Probable or definitive exposure was identified for 296 HCWs, and 287 subsequently received treatment or prophylaxis for B. pertussis infection. Direct medical center costs for treatment and prophylaxis were $13,416 and costs for personnel time were $19,500-$31,190. Indirect medical center costs for time lost from work were $51,300-$52,300. The total cost of these investigations was estimated to be $85,066-$98,456. CONCLUSIONS: Frequent B. pertussis exposures had a major impact on our facility. Given the impact of exposures on healthcare institutions, routine vaccination for HCWs may be beneficial.

Multifocal Rhizopus microsporus lung infection following brush clearing.

We report a case of pulmonary Rhizopus microsporus infection in a patient with untreated diabetes following brush clearing. The patient was successfully treated with a combined medical and surgical approach with complete resolution of the lung lesions and remains asymptomatic at 11-month follow-up.

T cell responses to an HLA-B*07-restricted epitope on the dengue NS3 protein correlate with disease severity.

Dengue hemorrhagic fever (DHF), the severe manifestation of dengue virus (DV) infection characterized by plasma leakage, is more common in secondary DV infections in previously infected individuals and is associated with high levels of immune activation. To determine the Ag specificity of this immune response, we studied the response to an HLA-B*07-restricted T cell epitope, residues 221-232 of the DV NS3 protein, in 10 HLA-B*07(+) Thai children who were studied during and after acute DV infections. Peptide-specific T cells were detected in 9 of 10 subjects. The frequency of peptide-specific T cells was higher in subjects who had experienced DHF than in those who had experienced DF. We also detected peptide-specific T cells in PBMC obtained at the time of the acute DV infection in 2 of 5 subjects. These data suggest that the NS3 (221-232) epitope is an important target of CD8(+) T cells in secondary DV infection and that the activation and expansion of DV-specific T cells is greater in subjects with DHF than in those with dengue fever. These findings support the hypothesis that activation of DV-specific CD8(+) T cells plays an important role in the pathogenesis of DHF.