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1.
Nat Commun ; 10(1): 2720, 2019 06 20.
Article in English | MEDLINE | ID: mdl-31221973

ABSTRACT

Public Health Laboratories (PHLs) in Puerto Rico did not escape the devastation caused by Hurricane Maria. We implemented a quality management system (QMS) approach to systematically reestablish laboratory testing, after evaluating structural and functional damage. PHLs were inoperable immediately after the storm. Our QMS-based approach began in October 2017, ended in May 2018, and resulted in the reestablishment of 92% of baseline laboratory testing capacity. Here, we share lessons learned from the historic recovery of the largest United States' jurisdiction to lose its PHL capacity, and provide broadly applicable tools for other jurisdictions to enhance preparedness for public health emergencies.

2.
Antiviral Res ; 93(3): 381-6, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22330888

ABSTRACT

During the 2009 influenza pandemic, the Centers for Disease Control and Prevention provided antiviral susceptibility testing for patients infected with suspected drug-resistant viruses. Specimens from 72 patients admitted to an intensive care unit or with a severe immunocompromising condition, who failed to clinically improve after oseltamivir treatment, were accepted for testing. Respiratory specimens were tested for the presence of the oseltamivir resistance-conferring H275Y substitution in the neuraminidase (NA) by pyrosequencing. Virus isolates propagated in MDCK cells were tested in phenotypic NA inhibition (NI) assays using licensed NA inhibitors (NAIs), zanamivir and oseltamivir, and investigational NAIs, peramivir and laninamivir. Conventional sequencing and plaque purification were conducted on a subset of viruses. Pyrosequencing data were obtained for 87 specimens collected from 58 of the 72 (81%) patients. Of all patients, 27 (38%) had at least one specimen in which H275Y was detected. Analysis of sequential samples from nine patients revealed intra-treatment emergence of H275Y variant and a shift from wildtype-to-H275Y in quasispecies during oseltamivir therapy. A shift in the H275Y proportion was observed as a result of virus propagation in MDCK cells. Overall, the NI method was less sensitive than pyrosequencing in detecting the presence of H275Y variants in virus isolates. Using the NI method, isolates containing H275Y variant at⩾50% exhibited resistance to oseltamivir and peramivir, but retained full susceptibility to zanamivir. H275Y viruses recovered from two patients had an additional substitution I223K or I223R that conferred a 38-52- and 33-97-fold enhancement in oseltamivir- and peramivir-resistance, respectively. These viruses also showed decreased susceptibility to zanamivir and laninamivir. These data suggest that pyrosequencing is a powerful tool for timely detection of NAI resistant viruses and that NI assays are needed for comprehensive testing to detect novel resistance substitutions.


Subject(s)
Antiviral Agents/pharmacology , Drug Resistance, Viral , Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza, Human/virology , Oseltamivir/pharmacology , Animals , Cell Line , Humans , Influenza A Virus, H1N1 Subtype/drug effects , Influenza A Virus, H1N1 Subtype/enzymology , Influenza A Virus, H1N1 Subtype/genetics , Influenza, Human/epidemiology , Mutation, Missense , Neuraminidase/genetics , Neuraminidase/metabolism , Pandemics , United States/epidemiology , Viral Proteins/genetics , Viral Proteins/metabolism
3.
J Clin Microbiol ; 47(3): 554-9, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19116353

ABSTRACT

Following introduction of the 7-valent pneumococcal conjugate vaccine to the United States, rates of invasive pneumococcal disease (IPD) caused by serotype 6A declined among all age groups, while rates of IPD caused by newly identified serotype 6C increased slightly among persons 5 years of age and older. Conventionally serotyped 6A isolates (CS6As) from active population-based surveillance during 1999 and 2006 to 2007 were classified as serotypes 6A and 6C by an expedient and highly accurate serotype 6C-specific PCR assay developed during this study. PCR testing of 636 year 1999, 2006, and 2007 CS6As revealed 6C proportions of 35/214 (16.4%), 141/218 (64.7%), and 141/204 (69.1%), respectively. These results agreed with those from a previously devised monoclonal antibody-based serotyping system (346 CS6As compared). Type 6C IPD incidence significantly increased during 2006 and 2007 compared to during 1999 (0.57 to 0.58 cases per 100,000 and 0.22 cases per 100,000, respectively; 164% increase from 1999 to 2007 [95% confidence interval, 87 to 270%]), while rates of IPD due to types 6A and 6B markedly decreased. In 2007, 31.2% of 6C isolates were not susceptible to penicillin. Serotype 6C is now the predominant serotype associated with serogroup 6 IPD in the United States and is often penicillin nonsusceptible. We performed multilocus sequence typing (MLST) on a limited sampling of 6C isolates with different antimicrobial susceptibility profiles. MLST of 42 6C isolates revealed 12 genotypes distributed among six distinct genetic groups. Fifteen 6C isolates shared one of four different MLST types with 6C-negative CS6As. MLST results suggest 6C strains arose from independent recombination events involving only serotype 6A and 6C parental strains.


Subject(s)
Bacterial Typing Techniques , DNA, Bacterial/genetics , Pneumococcal Infections/microbiology , Polymerase Chain Reaction/methods , Streptococcus pneumoniae/classification , Streptococcus pneumoniae/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Genotype , Humans , Incidence , Infant , Infant, Newborn , Male , Middle Aged , Molecular Epidemiology , Penicillin Resistance , Pneumococcal Infections/epidemiology , Serotyping , Streptococcus pneumoniae/isolation & purification , United States/epidemiology , Young Adult
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