Characterization of invasive Neisseria meningitidis from Atlantic Canada, 2009 to 2013: With special reference to the nonpolysaccharide vaccine targets (PorA, factor H binding protein, Neisseria heparin-binding antigen and Neisseria adhesin A).

BACKGROUND: Serogroup B Neisseria meningitidis (MenB) has always been a major cause of invasive meningococcal disease (IMD) in Canada. With the successful implementation of a meningitis C conjugate vaccine, the majority of IMD in Canada is now caused by MenB. OBJECTIVE: To investigate IMD case isolates in Atlantic Canada from 2009 to 2013. Data were analyzed to determine the potential coverage of the newly licensed MenB vaccine. METHODS: Serogroup, serotype and serosubtype antigens were determined from IMD case isolates. Clonal analysis was performed using multilocus sequence typing. The protein-based vaccine antigen genes were sequenced and the predicted peptides were investigated. RESULTS: The majority of the IMD isolates were MenB (82.5%, 33 of 40) and, in particular, sequence type (ST)-154 B:4:P1.4 was responsible for 47.5% (19 of 40) of all IMD case isolates in Atlantic Canada. Isolates of this clone expressed the PorA antigen P1.4 and possessed the nhba genes encoding for Neisseria heparin-binding antigen peptide 2, which together matched exactly with two of the four components of the new four-component meningococcal B vaccine. Nineteen MenB isolates had two antigenic matches, another five MenB and one meningitis Y isolate had one antigenic match. This provided 75.8% (25 of 33) potential coverage for MenB, or a 62.5% (25 of 40) overall potential coverage for IMD. CONCLUSION: From 2009 to 2013, IMD in Atlantic Canada was mainly caused by MenB and, in particular, the B:4:P1.4 ST-154 clone, which accounted for 47.5% of all IMD case isolates. The new four-component meningococcal B vaccine appeared to offer adequate coverage against MenB in Atlantic Canada.

HISTORIQUE: Le Neisseria meningitidis du sérogroupe B (MenB) a toujours été une cause importante de méningococcie invasive (MI) au Canada. Depuis l'adoption d'un vaccin conjugué contre le méningocoque du groupe C, la majorité des MI au Canada sont désormais attribuables au MenB. OBJECTIF: Examiner les isolats de cas de MI dans les Maritimes entre 2009 et 2013. Analyser les données pour déterminer la couverture potentielle du vaccin nouvellement homologué contre le MenB. MÉTHODOLOGIE: Les chercheurs ont déterminé le sérogroupe, le sérotype et les antigènes des sous-types sérologiques des isolats de cas de MI. Ils ont effectué l'analyse clonale au moyen du typage génomique multilocus. Ils ont séquencé les gènes des antigènes du vaccin à base de protéines et examiné les peptides prédits. RÉSULTATS: La majorité des isolats de MI étaient des MenB (82,5 %, 33 sur 40). Notamment, le type séquentiel (TS)-154 B:4:P1,4 était responsable de 47,5 % (19 sur 40) de tous les isolats de cas de MI dans les Maritimes. Les isolats de ce clone ont exprimé l'antigène porA P1.4 et étaient dotés des gènes nhba codant pour le peptide 2 de l'antigène de liaison à l'héparine de Neisseria. Ensemble, ces antigènes correspondaient exactement à deux des quatre composants du nouveau vaccin contre le méningocoque du groupe B à quatre composants. Dix-neuf isolats du MenB étaient dotés de deux correspondances antigéniques, tandis que cinq autres MenB et un isolat de la méningite Y étaient dotés d'une correspondance antigénique. Ces résultats assuraient une couverture potentielle du MenB de 72,7 % (24 sur 33) ou une couverture potentielle globale de la MI de 62,5 % (25 sur 40). CONCLUSION: De 2009 à 2013, dans les Maritimes, la MI était surtout causée par le MenB, en particulier le clone B:4:P1.4 ST-154, responsable de 47,5 % de tous les isolats de cas de MI. Le nouveau vaccin contre le méningocoque du groupe B à quatre composants semble offrir une couverture pertinente contre le MenB dans cette région.

West Nile virus: should pediatricians care?

Given the recurrent serious outbreaks of West Nile Virus (WNV) in the United States over the past decade, the spread to Canada and South America, the recurrent outbreaks in Europe, and the potential for serious neurological disease even in children under 18 years, paediatricians in affected areas must consider WNV in the differential diagnosis of all children presenting with aseptic meningitis, encephalitis and acute flaccid paralysis. Additionally, given that WNV encephalitis can occur after WNV infection, suspicion for neurological WNV disease must remain high even after otherwise benign febrile illnesses if the child lives in or has traveled to an affected region. Under-diagnosis in the pediatric population is likely a serious problem, necessitating further educational efforts. More follow-up studies of WNV neurological disease in children and youth are needed to better understand the potential long-term sequelae during vulnerable times of neurodevelopment and neural remodeling. Similarly, more research is need on short and long-term fetal outcomes of maternal WNV infection.

How to get and get rid of gonorrhea.

Gonorrhea remains as a significant public health concern with an estimated 88 million new cases per year globally. Gonorrhea is a disease of sexual networks and is most prevalent in youth, men who have sex with men, and the socioeconomically disadvantaged. Highly adaptive through years of co-evolution, gonorrhea has developed multiple ways of evading the human immune system. Although new molecular-based strategies have opened avenues for less invasive testing, education and accessibility issues persist. Novel strategies, including use of the internet and social media, are required to better target high risk groups for education, testing, and treatment. Increasing the availability of youth-friendly health services will also help foster earlier gonorrhea diagnosis and management. The inappropriate and overuse of antibiotics and propensity of gonococcus for mutation has led to growing microbe resistance. Treatment failures now include both oral and intravenous formulations of third generation cephalosporins; key front line recommended gonococcal treatment in many countries. With treatment options dwindling, the need for better preventative strategies has never been more important. This overview highlights some of the major aspects of gonococcal infection, including the epidemiology of the disease with an emphasis on sexual networks, new diagnostic techniques, treatment options in the face of evolving gonococcal resistance, and notes potential new preventative strategies.

Serratia marcescens outbreak in a neonatal intensive care unit related to the exit port of an oscillator.

OBJECTIVE: To interrupt transmission of Serratia marcescens colonization in a neonatal intensive care unit and determine the source of ongoing transmission. DESIGN: Multidisciplinary outbreak investigation and simulation of droplet generation by a high-frequency oscillator using fluorescent dye. SETTING: Level III neonatal intensive care unit. PATIENTS: Very low birth weight premature infants with respiratory failure. INTERVENTIONS: Infection control interventions, pulsed-field gel electrophoresis of isolates to determine relatedness, and construction of a scavenging system to capture the circuitry condensate expelled by the oscillator exit port. MEASUREMENTS AND MAIN RESULTS: Affected infants were housed in the same geographic site. Serratia marcescens isolates were indistinguishable or closely related using pulsed-field gel electrophoresis. Fluorescent droplet splatter from the circuitry, generated when no containment device covered the exit valve, was visible up to 49 in (107.8 cm) from the source. CONCLUSIONS: Implementation and adherence to infection control measures is essential to prevent transmission of opportunistic pathogens among ventilated infants. Oscillators can generate droplets that travel farther than 1 m from the source.

Gonococcal infections in newborns and in adolescents.

Gonococcal infections are now an uncommon problem in newborns in industrialized countries but remain a serious problem in developing countries due to ongoing high infection rates in pregnant women. Prompt diagnosis in the newborn with appropriate treatment can minimize sequelae. The mother and her partner(s) also require investigation and treatment. Adolescents are a core group fuelling the ongoing gonococcal epidemic in industrialized countries. This is unlikely going to change unless sexual behaviour changes substantially. Education is a critical step along with access to more youth friendly STI care. As noted in the 2001 Institute of Medicine Report, learning about sex, sexuality and prevention of STI is a basic human right of adolescents (DiClemente and Crosby 2006).

Isolation and genetic characterization of a coinfection of non-O157 Shiga toxin-producing Escherichia coli.

A coinfection of O177:NM and O55:H7 Shiga toxin-producing Escherichia coli (STEC) was identified for a child with acute bloody diarrhea and hemolytic uremic syndrome by using culture and serotype-specific molecular reagents. The profile of O157-related genetic islands revealed that the O55:H7 isolate was highly similar to O157 STEC whereas the O177:NM isolate lacked several fimbrial O islands and non-locus-of-enterocyte-effacement effector determinants. However, both STEC serotypes are known to cause serious disease, and the significant repertoire of virulence determinants in both strains made it impossible to determine their individual contributions to the clinical symptoms.

Routine surveillance for bloodstream infections in a pediatric hematopoietic stem cell transplant cohort: Do patients benefit?

BACKGROUND: Hematopoietic stem cell transplant (HSCT) recipients are at a high risk for late bloodstream infection (BSI). Controversy exists regarding the benefit of surveillance blood cultures in this immunosuppressed population. Despite the common use of this practice, the practical value is not well established in non-neutropenic children following HSCT. METHODS: At the IWK Health Centre (Halifax, Nova Scotia), weekly surveillance blood cultures from central lines are drawn from children following HSCT until the line is removed. A retrospective chart review was performed to determine the utility and cost of this practice. Eligible participants were non-neutropenic HSCT recipients with central venous access lines. The cost of laboratory investigations, nursing time, hospital stay and interventions for positive surveillance cultures was calculated. RESULTS: Forty-three HSCTs were performed in 41 children. Donors were allogenic in 33 cases (77%) and autologous in 10 cases (23%). There were 316 patient contacts for surveillance cultures (mean seven per patient) and 577 central line lumens sampled. Three of 43 patients (7%) had clinically significant positive surveillance blood cultures. Bacteria isolated were Klebsiella pneumoniae (n=2) and Corynebacterium jeikeium (n=1). All follow-up cultures before initiation of antimicrobial therapy were sterile. All three patients were admitted for antimicrobial therapy if they were not already hospitalized and/or had an uncomplicated course. The estimated total cost of BSI surveillance and management of asymptomatic infection over six years was $27,989. CONCLUSION: The present study suggests that BSI surveillance in children following HSCT engraftment has a very low yield and significant cost. It is unclear whether it contributes to improved patient outcomes.

First Canadian Reports of Cervical Adenitis Due to Mycobacterium Malmoense and a 10-year Review of Nontuberculous Mycobacterial Adenitis.

The present report reviews a decade of experience with nontuberculous mycobacterial adenitis at a pediatric referral centre, noting that patients are often subjected to multiple ineffective antibiotic courses, and that delays in diagnosis and referral for appropriate therapy are common. Notable clinical features include a mean age of presentation of 3.4 years, a male-to-female ratio of 1:1.5 and a gradual onset of painless, unilateral cervical adenopathy. Fever was absent in most patients (77%), and the disease failed to respond to antistaphylococcal antibiotics. The mean time to correct diagnosis was longer than three months (15 weeks). The clinical features of the disease are highlighted and presented with a practical diagnostic approach to the child with subacute/chronic adenitis. New molecular diagnostic tools and emerging mycobacteria are discussed, including the first reports of Mycobacterium malmoense adenitis in Canada.