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Before the introduction of the Haemophilus influenzae type b (Hib) conjugate vaccine, Hib was the most common cause of bacterial meningitis in children 80% of invasive H. influenzae disease among [...]

Objective. Haemophilus influenzae type b causes severe disease in nonimmune infants and young children; other serotypes are uncommon pathogens and thought to have low virulence. Some have hypothesized that with the virtual elimination of H influenzae type b, other serotypes might acquire virulence traits and emerge as important pathogens of children. We describe the clinical, epidemiologic, and molecular biologic features of 5 cases of severe disease attributable to Haemophilus influenzae type a. Methods. After observing 4 cases of invasive disease caused by H influenzae type a, we reviewed microbiology records at 3 reference laboratories that perform all serotyping in Utah and surveillance databases. Strains of H influenzae type a and control strains were examined by Southern blotting with the use of the cap probe pUO38 and by pulsed-field gel electrophoresis. The putative virulence mutation, the IS1016-bexA deletion, was detected by polymerase chain reaction amplification and sequencing. Results. During a 10-month period, we observed 5 children with severe invasive disease caused by H influenzae type a. No isolates of H influenzae type a had been submitted to the reference laboratories between 1992 and 1998. The median age of patients was 12 months (range: 6-48 months). Four of 5 had meningitis and bacteremia; 1 had purpura fulminans. Three isolates, representing 1 of 2 pulsed-field gel electrophoresis patterns, contained the IS1016-bexA deletion and were associated with particularly severe disease. Conclusions. We describe an unusual cluster of severe disease caused by H influenzae type a that resembles the clinical and epidemiologic features of H influenzae type b disease. Our data support the hypothesis that the IS1016-bexA deletion may identify more virulent strains of H influenzae. Pediatrics 2001;107(7). URL: http://www. pediatrics.org/cgi/content/full/107/7/e18; Haemophilus influenzae, epidemiology, virulence, serotyping, pathogenicity.

Objective. Our objective was to confirm an observed temporal association of increased numbers of rheumatic fever cases concomitant with the appearance of an increased prevalence of mucoid strains of Streptococcus pyogenes. During the resurgence of rheumatic fever (RF) that has occurred in the Intermountain area surrounding Salt Lake City, Utah, since 1985, the largest number of cases occurred in 1985 and 1986 and 12 years later in 1997 and 1998. During the initial outbreak and the later exacerbation of the resurgence, an increased number of mucoid strains of S pyogenes were present in the community. Methods. The referred cases of RF that fulfilled Jones criteria have been systematically reviewed by the medical staff at Primary Children's Medical Center yearly since 1985. Before the resurgence of RF, a program was initiated by the microbiology laboratory at Primary Children's Medical Center to store frozen isolates of S pyogenes. All frozen specimens were randomly selected and entered into a log; the coded entry allowed for comments regarding the origin of the isolate and whether the isolate had a mucoid appearance on the blood agar culture plate. This log was reviewed in October 2002 to determine whether the percentage of frozen mucoid isolates stored during the resurgence of RF would support the clinical and epidemiologic suspicion that mucoid isolates seemed to be present with a higher frequency during the 2 periods of high incidence of RF. The percentage of mucoid isolates was compared with the yearly number of cases of RF. A Pearson r correlation analysis was completed to determine whether there was a significant association between the percentage of mucoid isolates and the number of cases of RF. Results. The highest number of cases of RF was temporally associated with the highest percentage of mucoid isolates. There was statistically significant correlation between percentage of mucoid strains and the number of RF cases. Conclusions. The Utah experience with the resurgence of RF in a civilian population during the last decade and a half of the 20th century confirmed the temporal association of mucoid strains of S pyogenes, primarily M-type 18, with a high incidence of RF. Pediatrics 2004;113:e168-e172. URL: http://www.pediatrics. org/cgi/content/full/113/3/e168; rheumatic fever, mucoid strains, Streptococcus pyogenes.

Background. Human metapneumovirus (HMPV) causes acute respiratory tract infections in infants and children. We sought to measure the clinical and economic burden of HMPV infection in hospitalized children. Methods. We conducted a retrospective cohort study from 2007 to 2013 at Primary Children's Hospital in Salt Lake City, Utah. Children <18 years of age with laboratory-confirmed HMPV infection were included. Demographic, clinical, and financial data were abstracted from the electronic medical record. Results. During the study period, 815 children were hospitalized with laboratory-confirmed HMPV infection: 16% <6 months, 50% 6-23 months, 23% 2-4 years, and 11% 5-17 years of age. A complex chronic condition was identified in 453 (56%) children hospitalized with HMPV infection; this proportion increased with increasing age (P < .001). There was marked variation in annual HMPV hospitalization rates, ranging from 9 of 100 000 person-years in 2012-2013 to 79 of 100 000 in 2009-2010. Hospitalization rates were highest among children <2 years (200 of 100 000 person-years) and lowest among children 5-17 years of age (5 of 100 000). Of hospitalized children, 18% were treated in the intensive care unit and 6% required mechanical ventilation. The median length of stay was 2.8 days (interquartile range [IQR], 1.8-4.6) and did not vary by age. The median total hospital cost per patient was $5513 (IQR, $3850-$9946) with significantly higher costs for patients with chronic medical conditions (P < .001). Conclusions. Human metapneumovirus infection results in a large number of hospitalizations with substantial morbidity, resource utilization, and costs. The development of a safe and effective vaccine could reduce the clinical and economic burden of HMPV. [ABSTRACT FROM AUTHOR]

Across 12 consecutive influenza seasons in Utah, medically-attended visits for laboratory-confirmed influenza infection peaked first among older children (12–18 years). Peak activity in older children preceded that of children 0–4 years by more than 2 days and that of peak activity among adults ≥65 years by more than 6 days. [ABSTRACT FROM PUBLISHER]

Background. The incidence of invasive Haemophilus influenzae infection decreased dramatically since the introduction of the H. influenzae serotype b (Hib) conjugate vaccine. H. influenzae invasive disease continues to occur and cause significant morbidity and mortality in children aged <5 years. We aimed to report the epidemiology and serotypes of invasive H. influenzae disease in children from Utah in the post-Hib vaccine era. Methods. We identified all cases of invasive H. influenzae disease, defined as H. influenzae isolated from a sterile site, during the period 1998-2008 among children aged <18 years who were living in Utah. Results. We identified 91 cases of invasive H. influenzae disease in children. Children aged <5 years accounted for 78 cases (86%). H. influenzae serotype a (Hia) was the most common serotype (22 cases), representing 28% of all cases of invasive disease among children aged <5 years. The majority (15 cases [93%]) of Hib disease cases occurred among children aged <5 years and accounted for 18% of all cases of H. influenzae invasive disease in this age group. The mean incidence of Hia disease increased from 0.8 cases per 100,000 child-years in 1998 to 2.6 cases per 100,000 child-years in 2008. The incidence of Hib disease among children aged <5 years remained steady at 0.5 cases per 100,000 child-years. Bacteremia accounted for 61% of all cases of invasive disease. One-half (13 of 26) of cases of H. influenzae meningitis were due to Hia. Conclusions. H. influenzae continues to cause invasive disease in Utah children. Hia is the primary cause of the overall increased incidence of invasive H. influenzae disease and leads to disease similar to Hib. Isolated cases of Hib disease demonstrate a continued reservoir. The success of the Hib conjugate vaccine may therefore be vulnerable to vaccine shortages and refusal of vaccination. [ABSTRACT FROM AUTHOR]

The original reports of human infection with Francisella tularensis noted vesicular skin rash as a manifestation. We present 2 cases of tularemia initially diagnosed as herpes simplex or varicella zoster infection. Clinicians must recognize the cutaneous manifestations of tularemia and be able to distinguish these from lesions seen with herpes viruses. [ABSTRACT FROM AUTHOR]

Background Haemophilus influenzae causes serious invasive disease across all ages, but has not been widely described in neonatal early-onset sepsis (EOS). EOS, likely caused by organisms acquired from the mother, can lead to significant morbidity and mortality, particularly for preterm infants. There are reports of increasing ampicillin resistance in H. influenzae. We describe a case series of EOS due to H. influenzae at our institution. Methods Neonatal H. influenzae EOS was identified based on positive sterile site cultures at <72 hours of life in infants hospitalized at an Intermountain Healthcare (IHC) facility from 2007–2017. Demographics, clinical and microbiologic data were obtained through an IRB-approved electronic chart and microbiology review. Results Twelve neonates with H. influenzae EOS were identified over 11 years. Nine were preterm (<37 weeks); five were extremely preterm (<28 weeks). Eight had low birth weight (<2,500 g); five had very low birth weight (<1,500 g). Most (66%) mothers were primigravida; median maternal age was 24.5 years. Only four (33%) mothers had prolonged rupture of membranes (>24 hours). All infants had signs and symptoms of sepsis within 24 hours of birth. The majority (10/12) had a blood culture positive for H. influenzae from the time of delivery. Two infants had negative delivery blood cultures but a H. influenzae -positive placental culture. No infant had > 1 day of bacteremia. One H. influenzae isolate was serotype b, one serotype c and one non-typeable, but most isolates (9/12) were not serotyped. Only one isolate produced a β-lactamase. All infants were empirically started on ampicillin and gentamicin at delivery. Nine infants underwent lumbar puncture, two were suggestive of meningitis but cultures were negative. Five infants developed interventricular hemorrhage and six required vasoactive medications. No infant died. Conclusion H. influenzae is an infrequent but important cause of neonatal EOS. H. influenzae EOS occurred in infants with known risk factors, including prolonged rupture of membranes, prematurity, and low birth weight. Recognition of H. influenzae as a potential pathogen in EOS has implications for the use of empiric antibiotic therapy particularly ampicillin, in septic neonates. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]

Background Following widespread use of the Haemophilus influenzae serotype b (Hib) vaccine, H. influenzae serotype a (Hia) has emerged as an important pathogen in children. Rates of Hia disease are particularly high in Utah. We describe the clinical features and molecular epidemiology of invasive Hia disease in children in Utah over 11 years. Methods Cases of invasive Hia disease in children less than 18 years were identified through electronic clinical and microbiology records. Demographic data and clinical outcomes were abstracted from the medical record for all cases. Available Hia isolates were collected for molecular analysis. Isolates were genotyped by multi-locus sequence typing (MLST) and clonal division was determined using sodC PCR. Presence or absence of the putative virulence-associated IS 1016-bexA duplication-deletion was evaluated. Results We identified 51 children with invasive Hia between 2007 and 2017. Median age was 11.3 months. The average annual incidence was 1.7 cases per 100,000 children aged <5 years (95% CI 1.2–2.2). Incidence was highest among children less than one year of age (4.8/100,000; 95% CI 3.1–6.9). Incidence rates were similar by race and ethnicity, although the confidence intervals were wide. The annual number of cases was similar over the 11-year study period (figure). The most common clinical manifestation was meningitis (54%; half had intracranial complications, 25% suffered hearing loss), followed by pneumonia (14%), and arthritis (14%). Twenty-two children (44%) required ICU care and one child died. Twenty-eight isolates (56%) were available for molecular analysis. ST62, clonal division II isolates caused 75% (21/28) of disease. No isolates contained the virulence-associated IS 1016 - bexA duplication-deletion. Conclusion Hia is an important cause of severe invasive bacterial infection in Utah. Molecular analyses revealed that a majority of infections were caused by ST62 isolates, a clonal division II Hia type lacking the IS 1016 - bexA duplication-deletion. Hia ST62 has not been commonly reported in other settings, suggesting a unique molecular epidemiology in our population. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]

BACKGROUND: Infants <6 months old with influenza are at risk for adverse outcomes. Our objective was to compare influenza outcomes in infants <6 months old born to women who did and did not report influenza vaccine during pregnancy. METHODS: The study included all women who delivered from 12/2005 to 3/2014 at Intermountain facilities and their infants. Influenza outcomes included infant influenza-like illness (ILI), laboratory-confirmed influenza, and influenza hospitalizations. RESULTS: The cohort included 245 386 women and 249 387 infants. Overall, 23 383 (10%) pregnant women reported influenza immunization. This number increased from 2.2% before the H1N1 pandemic to 21% postpandemic (P < .001). A total of 866 infants <6 months old had ≥1 ILI encounter: 32 (1.34/1000) infants born to women reporting immunization and 834 (3.70/1000) born to women who did not report immunization (relative risk [RR] 0.36; 95% confidence interval [CI), 0.26-0.52; P < .001). A total of 658 infants had laboratory-confirmed influenza: 20 (0.84/1000) born to women reporting immunization and 638 (2.83/1000) born to unimmunized women (RR 0.30; 95% CI, 0.19-0.46; P < .001). A total of 151 infants with laboratory-confirmed influenza were hospitalized: 3 (0.13/1000) born to women reporting immunization and 148 (0.66/1000) born to unimmunized women (RR 0.19; 95% CI, 0.06-0.60; P = .005). CONCLUSIONS: Self-reported influenza immunization during pregnancy was low but increased after the H1N1 pandemic. Infants born to women reporting influenza immunization during pregnancy had risk reductions of 64% for ILI, 70% for laboratory-confirmed influenza, and 81% for influenza hospitalizations in their first 6 months. Maternal influenza immunization during pregnancy is a public health priority. [ABSTRACT FROM AUTHOR]