A large HCV transmission network enabled a fast-growing HIV outbreak in rural Indiana, 2015.

BACKGROUND: A high prevalence (92.3%) of hepatitis C virus (HCV) co-infection among HIV patients identified during a large HIV outbreak associated with injection of oxymorphone in Indiana prompted genetic analysis of HCV strains. METHODS: Molecular epidemiological analysis of HCV-positive samples included genotyping, sampling intra-host HVR1 variants by next-generation sequencing (NGS) and constructing transmission networks using Global Hepatitis Outbreak and Surveillance Technology (GHOST). FINDINGS: Results from the 492 samples indicate predominance of HCV genotypes 1a (72.2%) and 3a (20.4%), and existence of 2 major endemic NS5B clusters involving 49.8% of the sequenced strains. Among 76 HIV co-infected patients, 60.5% segregated into 2 endemic clusters. NGS analyses of 281 cases identified 826,917 unique HVR1 sequences and 51 cases of mixed subtype/genotype infections. GHOST mapped 23 transmission clusters. One large cluster (n = 130) included 50 cases infected with ≥2 subtypes/genotypes and 43 cases co-infected with HIV. Rapid strain replacement and superinfection with different strains were found among 7 of 12 cases who were followed up. INTERPRETATION: GHOST enabled mapping of HCV transmission networks among persons who inject drugs (PWID). Findings of numerous transmission clusters, mixed-genotype infections and rapid succession of infections with different HCV strains indicate a high rate of HCV spread. Co-localization of HIV co-infected patients in the major HCV clusters suggests that HIV dissemination was enabled by existing HCV transmission networks that likely perpetuated HCV in the community for years. Identification of transmission networks is an important step to guiding efficient public health interventions for preventing and interrupting HCV and HIV transmission among PWID. FUND: US Centers for Disease Control and Prevention, and US state and local public health departments.

Notes from the Field: Expanded Chemoprophylaxis Offered in Response to a Case of Meningococcal Meningitis in an Elementary School - Indiana, 2015.

On December 11, 2015, the Fort Wayne-Allen County (Indiana) Department of Health was notified by a local hospital laboratory of a suspected case of meningococcal meningitis based on Gram stain results of cerebrospinal fluid. The county health department interviewed close family members and friends of the patient to establish an infectious period, timeline of events, and possible exposures. Close medical and household contacts were offered chemoprophylaxis (1). This case was associated with an elementary school. The patient had intermittent, close, potentially face-to-face contact with many students, and was reported to have had a persistent, productive cough throughout the exposure period. In light of these unusual circumstances, and the fact that elementary school-aged children are not routinely vaccinated against meningococcal disease,* local and state health officials, with CDC support, decided to offer chemoprophylaxis to the patient's contacts. A total of 581 child and adult contacts were identified.