Influenza Vaccine Effectiveness Among Children for the 2017-2018 Season.

BACKGROUND: The 2017-2018 influenza season was of high severity. Circulating influenza strains change periodically, making it important to determine vaccine effectiveness on an annual basis, especially for susceptible populations. The primary aim of our study was to estimate the effectiveness of the influenza vaccine among children. Secondary aims were to assess the effect of previous season vaccination and intraseasonal waning of immunity. METHODS: Children 6 months to 17 years of age tested for influenza during the 2017-2018 season were included. Clinical charts were reviewed, and immunization status was confirmed via the Louisiana Immunization Registry. Influenza vaccine effectiveness (IVE) was estimated in a test-negative design by comparing vaccination status of influenza-positive vs influenza-negative cases. RESULTS: A total of 3595 children were included, 26% of whom tested positive for influenza, mostly type A (79%); 15% had received an influenza vaccine prior to illness: 8% among the influenza-positive and 17% among influenza-negative cases (P <.0001). IVE for the 2017-2018 influenza season was 52% overall (95% confidence interval, 38%-62%), 49% for influenza A, and 60% for influenza B. While receiving current year (2017-2018) vaccine had the most effect, receiving the previous year (2016-2017) vaccine had a small benefit and no interference. We found no evidence of waning immunity of the vaccine for the 2017-2018 season. CONCLUSIONS: IVE was moderate for children. Previous year vaccination had a small but significant benefit and there was no evidence of waning immunity in our cohort. Ongoing national and local surveillance is important to understand the benefit of influenza vaccination.

A Survey About Fever Knowledge, Attitudes, and Practices Among Parents.

A 21-question survey was conducted among parents attending 4 pediatric outpatient practices to assess their knowledge, perceptions, and attitudes about fever. One hundred and ninety-seven surveys were included. Most commonly the participating parent was the mother. Parents used mainly axillary thermometers to measure child's temperature and mentioned integers for their definition of fever, 100°F being the most frequent answer. Most parents would treat all fevers and would use alternating antipyretics. Parents had a generally negative perception of fever: only one third thought fever may have some benefit, and more than half thought there must be some risk. A positive perception of fever was associated with parental educational level but not with information by the pediatrician. There is much confusion about fever among our parents, a negative perception is prevalent, and parents seem to receive-or recall-little information from the pediatrician.

Live Attenuated and Inactivated Influenza Vaccine Effectiveness.

BACKGROUND: Researchers in observational studies of vaccine effectiveness (VE) in which they compared quadrivalent live attenuated vaccine (LAIV4) and inactivated influenza vaccine (IIV) among children and adolescents have shown inconsistent results, and the studies have been limited by small samples. METHODS: We combined data from 5 US studies from 2013-2014 through 2015-2016 to compare the VE of LAIV4 and IIV against medically attended, laboratory-confirmed influenza among patients aged 2 to 17 years by influenza season, subtype, age group, and prior vaccination status. The VE of IIV or LAIV4 was calculated as 100% × (1 - odds ratio), comparing the odds of vaccination among patients who were influenza-positive to patients who were influenza-negative from adjusted logistic regression models. Relative effectiveness was defined as the odds of influenza comparingLAIV4 and IIV recipients. RESULTS: Of 17 173 patients aged 2 to 17 years, 4579 received IIV, 1979 received LAIV4, and 10 615 were unvaccinated. Against influenza A/H1N1pdm09, VE was 67% (95% confidence interval [CI]: 62% to 72%) for IIV and 20% (95% CI: -6% to 39%) for LAIV4. Results were similar when stratified by vaccination in the previous season. LAIV4 recipients had significantly higher odds of influenza A/H1N1pdm09 compared with IIV recipients (odds ratio 2.66; 95% CI: 2.06 to 3.44). LAIV4 and IIV had similar effectiveness against influenza A/H3N2 and B. Our overall findings were consistent when stratified by influenza season and age group. CONCLUSIONS: From this pooled individual patient-level data analysis, we found reduced effectiveness of LAIV4 against influenza A/H1N1pdm09 compared with IIV, which is consistent with published results from the individual studies included.

Necrotizing Pneumonia Caused by Chromobacterium violaceum: Report of a Rare Human Pathogen Causing Disease in an Immunodeficient Child.

Chromobacterium violaceum is a rare, potentially serious pathogen. Most clinicians have no experience with its clinical appearance or treatment. We describe a case of a child presenting with necrotizing pneumonia caused by C. violaceum. We describe case complexities, including the need for a multidisciplinary approach to diagnosis and treatment.

Otitis Media with Effusion and Helicobacter pylori.

Previous studies reported the presence of Helicobacter pylori in middle ear fluid and raised a possible causal role of this bacterium in otitis media with effusion (OME). We investigated 48 children with OME (age, 7 months to 12 years) seen in New Orleans, Louisiana, and found no evidence of H pylori presence in any middle ear fluid specimen by amplification of the 16S rRNA gene. One child had H pylori detected in a stool specimen, in accordance with the low prevalence in our population. While H pylori may be significant in other countries, these findings do not support a role for H pylori in OME in our pediatric population in the United States.

Influenza vaccines effectiveness 2013-14 through 2015-16, a test-negative study in children.

BACKGROUND: Trivalent inactivated and live attenuated influenza vaccines (IIV3 and LAIV3) have been reformulated with an extra B strain (IIV4 and LAIV4). They were licensed based on immunogenicity and their effectiveness (VE) still must be empirically tested. METHODS: Children 1-17years tested for influenza during 2013-16 were included and their immunization status verified. They were considered vaccinated if received ≥1 dose of an influenza vaccine ≥10days before evaluated for a respiratory episode. Age-groups were classified as 1-4years or 5-17years. VE was estimated by comparing vaccination status of influenza-positive versus influenza-negative cases. RESULTS: 6779 children were enrolled in the three seasons. Overall, 27.2% received an influenza vaccine (87.1% IIV3 or IIV4 and 12.9% LAIV4), and 15.6% tested positive for influenza (77.9% A). IIV3 was predominantly used in 2013-14 and IIV4 in 2014-15 and 2015-16. IIV3 and IIV4 had comparable VE over the three seasons (60%, 57% and 53%) and performed similarly against influenza A and B and both age-groups. LAIV4 performed poorly for influenza A (15%, 37% and 48%) but better for influenza B (100%, 56% and 100%), especially among children 5-17years of age with VE=100% (95%CI: 55, 100). CONCLUSIONS: Influenza vaccination showed modest but consistent effectiveness over the years. The switch from IIV3 to IIV4 did not affect VE. LAIV4 did not perform as well as IIVs, yet it improved over the years and was particularly good protecting older children against influenza B. These results emphasize the regional nature of influenza and the need for local surveillance.

Löffler syndrome on a Louisiana pig farm.

Löffler syndrome, a fulminant eosinophilic pneumonitis associated with the larval migratory phase of human parasites, is rarely reported in the United States. A previously healthy 8-year-old male was hospitalized with tachypnea, cough, hypoxemia, and fever of one week's duration. History revealed exposure to pigs on his family's farm in southernmost Louisiana, where the patient was responsible for cleaning the farm's pigpens. His fingernails were soiled and extremely short, with the edge of the nail bed exposed secondary to onychophagia. Laboratory evaluation demonstrated peripheral eosinophilia (39%), pulmonary eosinophilia (86%), high total IgE, diffuse reticulonodular lung opacities, and mixed obstructive and restrictive pulmonary function pattern. Systemic corticosteroids were initiated for his acute respiratory insufficiency and produced rapid clinical improvement. Serum Ascaris-specific IgE was markedly elevated and he was treated with albendazole. An extensive evaluation for other infectious and allergic etiologies was negative. A site visit to the family farm and laboratory investigation was coordinated with the Louisiana Animal Disease Diagnostic Laboratory at LSU. Ascaris suum eggs were detected in fresh pig feces and in the soil immediately surrounding the pens. Ascariasis should be considered even in the absence of travel history, especially in swine raising areas that are endemic for Ascaris in pigs, such as the southeastern United States. Onychophagia is a highly probable mechanism of zoonotic fecal-oral transmission in this case, and such habits could lead to continual reinfection. Systemic corticosteroids were effective in treating the patient's acute respiratory compromise due to Löffler syndrome.

Primary Osteomyelitis of the Clavicle in Children.

Osteomyelitis of the clavicle is a rare entity with a broad differential diagnosis and high potential for complications if not diagnosed promptly and treated appropriately. The threshold for surgical intervention should be low to prevent osteonecrosis and bony resorption. In addition, although rare, life-threatening complications have been reported. This report describes primary osteomyelitis of the clavicle that was diagnosed in a 22-month-old girl on her third clinical evaluation after 4 days of symptoms. She presented to a children's tertiary care emergency department with fever and acute pain and swelling of her right shoulder and arm. The diagnosis was confirmed through clinical, laboratory, and imaging studies including ultrasound; these revealed subperiosteal abscess formation, which may have developed in part as the result of a delayed diagnosis from the 2 prior emergency department visits. The patient was treated initially with intravenous antibiotics and underwent therapeutic as well as diagnostic needle-guided tissue aspiration under ultrasound guidance. This ruled out malignancy but was not curative, and the subperiosteal abscess recurred within 24 hours, prompting formal operative irrigation and debridement. The patient was seen for 12-month follow-up and has had no complications or evidence of recurrence. This case emphasizes the need for a high index of suspicion to prevent diagnostic delays as well as the importance of a low threshold for surgical debridement to minimize the potential for complications that could prolong the treatment course. [Orthopedics. 2016; 39(4):e760-e763.].

Species-based comparison of disease severity and risk factors for disseminated Candida infections in pediatric patients.

BACKGROUND: Pediatric Candida infections are associated with worse clinical outcomes and increased costs. Yet, it is not definitively known if particular species are associated with more severe illness. Differential risk factor exposures among the species group may also exist. We aimed to determine whether certain Candida species are more strongly associated with worse outcomes, and whether certain risk factors more strongly predispose patients to infection with certain species. METHODS: Microbiology lab records from patients seen from 2003 to 2010 at an urban children's hospital were reviewed for invasive or disseminated Candida infections. Data on measures of disease severity/outcome and risk factors were abstracted and analyzed to determine differences associated with various Candida species. RESULTS: Exactly 106 cases of infection were analyzed. Non-albicans species were associated with a significantly longer length of stay postdiagnosis (P=0.03), as well as longer treatment (P=0.02). Candida albicans was associated with a higher number of antihypotensive medications required (P=0.03) and length of mechanical ventilation postdiagnosis (P=0.05). Candida tropicalis was associated with the highest mortality (45.5%). Hypotension, which was found to be significantly associated with concurrent infection, was significantly associated with increased risk of mortality (odds ratio =5.85, P=0.005). Initial choice of antifungal therapy was not associated with differences in eventual patient mortality. Multivariate logistic regression modeling revealed a trend toward C. albicans infection in patients receiving antineoplastic chemotherapy and non-albicans infection in patients with >96 hours mechanical ventilation. CONCLUSION: Interspecies differences may exist for Candida in terms of disease severity and risk factors. Underlying morbidity and the role of concurrent infections may play a key role in poor outcomes.

Correlates of improved influenza vaccination of healthcare personnel: a survey of hospitals in Louisiana.

OBJECTIVE: To describe practices for influenza vaccination of healthcare personnel (HCP) with emphasis on correlates of increased vaccination rates. DESIGN: Survey. PARTICIPANTS: Volunteer sample of hospitals in Louisiana. METHODS: All hospitals in Louisiana were invited to participate. A 17-item questionnaire inquired about the hospital type, patients served, characteristics of the vaccination campaign, and the resulting vaccination rate. RESULTS: Of 254 hospitals, 153 (60%) participated and were included in the 124 responses that were received. Most programs (64%) required that HCP either receive the vaccine or sign a declination form, and the rest were exclusively voluntary (36%); no program made vaccination a condition of employment. The median vaccination rate was 67%, and the vaccination rate was higher among hospitals that were accredited by the Joint Commission; provided acute care; served children, pregnant women, oncology patients, or intensive care unit patients; required a signed declination form; or imposed consequences for unvaccinated HCP (the most common of which was to require that a mask be worn on patient contact). Hospitals that provided free vaccine, made vaccine widely available, advertised the program extensively, required a declination form, and imposed consequences had the highest vaccination rates (median, 86%; range, 81%-91%). CONCLUSIONS: The rate of influenza vaccination of HCP remains low among the hospitals surveyed. Recommended practices may not be enough to reach 90% vaccination rates unless a signed declination requirement and consequences are implemented. Wearing a mask is a strong consequence. Demanding influenza vaccination as a condition of employment was not reported as a practice by the participating hospitals.

Experience with pandemic 2009 H1N1 influenza in a large pediatric hospital.

OBJECTIVE: In 2009, a new strain of influenza A, H1N1, was detected in two children in the United States. It spread quickly and became pandemic (pH1N1), disproportionately affecting children. The aim of the present study was to describe our experience with pH1N1 in a large pediatric hospital. METHODS: We reviewed the clinical records of all of the children diagnosed as having influenza A at Children's Hospital, New Orleans, LA, for the period April 2009 to May 2010. Diagnosis was made by rapid influenza test or direct fluorescent antibody. Specimens form hospitalized children were sent to the Louisiana Office of Public Health for confirmation by reverse-transcription-polymerase chain reaction. RESULTS: During the 14-month study period, 10,470 children were tested and 1463 (14%) tested positive for influenza A. Boys were more commonly infected than girls (53% vs 47%, P < .001). Of the cases, 1308 (89%) were ambulatory and 155 (11%) were hospitalized. Hospitalized children were younger, more frequently white, had non-Medicaid insurance, and had comorbidity. Of the 155 admissions, 14 (9%) were admitted to the intensive care unit. Having a comorbidity increased and being black decreased the chances of being admitted to the intensive care unit. Three children died, all with severe neurologic or respiratory predisposing illness. Eight cases of hospital-onset influenza and 6 of repeat infection were detected. CONCLUSIONS: pH1N1 burdened pediatric facilities during the 2009-2010 influenza season. Even though most cases were mild and self-limited, some resulted in severe disease and long-term complications.

Use of palivizumab in primary practice.

OBJECTIVE: To describe the implementation of a program for the use of palivizumab in a general pediatrics office and evaluate adherence to the 2009 American Academy of Pediatrics (AAP) guidelines. METHODS: Pediatricians in a large practice were educated in the diagnosis and management of bronchiolitis, with specific attention to the AAP's palivizumab administration guidelines. During the 2009-2010 and 2010-2011 respiratory syncytial virus seasons, children were systematically identified and enrolled for palivizumab administration. Indication for administration was determined by gestational age, age at the beginning of the respiratory syncytial virus season, pertinent diagnoses, and presence of risk factors. RESULTS: In the 2009-2010 season, 161 children were enrolled to receive palivizumab, 86 of whom (53%) conformed with AAP guidelines. In contrast, in 2010-2011, a total of 85 children were enrolled to receive palivizumab, and 73 (86%) conformed with the guidelines. As a consequence, the total cost of palivizumab (US $: 511 559 vs 1 500 670) and the cost per child (US $: 6018 vs 9438) were lower in 2010-2011 than in 2009-2010. However, of the children selected within the AAP guidelines, only 29% received the appropriate number of doses, whereas 62% and 9% received fewer or excessive doses, respectively; these findings were similar for the 2 seasons. CONCLUSIONS: In a primary practice, use of palivizumab outside of the AAP guidelines was frequent and manifested as inadequate indications or inadequate number of doses. The former improved with education and standardization of care (suggesting provider problems), while the latter did not (suggesting system problems). Additional interventions are required.

Pandemic (H1N1) 2009 outbreak at camp for children with hematologic and oncologic conditions.

An outbreak of influenza A pandemic (H1N1) 2009 occurred among campers and staff at a summer camp attended by children with hematologic and oncologic conditions. The overall attack rate was 36% and was highest among children and adolescents (43%), persons with cancer (48%), and persons with sickle cell disease (82%).

Protective efficacy of recombinant urease B and aluminum hydroxide against Helicobacter pylori infection in a mouse model.

Efforts are underway for the development of an effective vaccine against Helicobacter pylori infection. We prepared recombinant full-length (568 aa) H. pylori recombinant urease B (rUreB) protein and tested it for immunogenicity and protection. BALB/c mice received either rUreB (40 µg) plus CpG (10 µg) intranasally, rUreB (50 µg) plus 3% aluminum hydroxide (50 µL) intramuscularly or rUreB (25 µg) plus Freund's adjuvant (25 µL) subcutaneously, three times (weeks 0, 2 and 6). Intranasal rUreB plus CpG was neither immunogenic nor protective; intramuscular rUreB plus aluminum hydroxide was immunogenic and modestly protective, and subcutaneous rUreB plus Freund's adjuvant was immunogenic and highly protective. The fact that protection was improved with Freund's adjuvant indicates that rUreB is a good antigen for a vaccine but that it needs a stronger adjuvant than aluminum hydroxide.

Reduction in gastroenteritis with the use of pentavalent rotavirus vaccine in a primary practice.

OBJECTIVES: Pentavalent rotavirus (RV) vaccine (RV5) was licensed in 2006 and recommended for routine childhood immunization. A significant decrease in the number of RV hospitalizations has been described. The objective of this study was to evaluate the effect of RV5 on acute gastroenteritis (AGE) seen in a primary practice. METHODS: In July 2004, surveillance was initiated among children who were younger than 5 years and seen in a large pediatric practice in New Orleans for those who presented AGE, as determined by International Classification of Diseases, Ninth Revision codes. Primary care physician office visits, emergency department visits, and hospital admissions were identified by review of records. RV testing was performed only on those who were seen at the hospital. RESULTS: Approximately 16,000 children who were younger than 5 years were followed in the practice during each year. For 2006-2007, 2007-2008, and 2008-2009, 11.1%, 40.3%, and 45.6% of age-eligible children, respectively, received > or =1 dose of RV5. As compared with 2004-2005 (before RV5), in 2007-2009, there was a significant decrease in all-cause AGE office visits (23%) and hospitalizations (50%). RV-positive cases (emergency department visits or hospitalizations) decreased by 67%. The decrease in RV-positive cases was more evident among children who were younger than 2 years (81%), with a strong trend among those who were aged 2 to <5 years (41%). CONCLUSIONS: Increased use of RV5 in a pediatric practice was associated with fewer AGE office visits and hospitalizations. The reduction was specific for RV-positive AGE and seen among children who were targeted for immunization as well as older groups, suggesting a herd-immunity effect.

Immunogenicity of Recombinant Helicobacter pylori Urease B Administered by Various Routes and with Different Adjuvants.

Because of the high prevalence of Helicobacter pylori infection and the morbidity and mortality associated to the disease, development of a preventive vaccine has become a priority. To this goal, we produced recombinant H. pylori urease B (rUreB) and tested its immunogenicity in BALB/c mice when administered as 3 doses (week 0, 4 and 6) by either parenteral (intramuscular) or mucosal routes (intragastric, intranasal, intrarectal) and with the use of various adjuvants (none, CpG, alum or Freund's). The intramuscular route was more immunogenic than any mucosal route; of the mucosas, only intranasal induced modest levels of serum IgG. All adjuvants improved the seroresponse to plain rUreB and, of them, Freund's and alum were equally good and better than CpG ODN 1826. Stool IgA was barely detected by any immunization strategy.

Immunogenicity of Helicobacter pylori urease B protein and DNA vaccines in a mouse model.

A vaccine could alleviate major morbidity and mortality associated with Helicobacter pylori infection. We immunized BALB/c mice with 3 doses of a protein or DNA vaccine based on H pylori urease B. Protein alone was immunogenic even after the first dose, whereas DNA did not elicit antibodies after 3 doses. DNA preceding protein (D-P-P) appeared to blunt the response to protein, whereas DNA following protein (P-D-D) shifted from a predominantly T helper 2 (Th2) profile to a balanced Th1:Th2 profile. These preliminary findings may have important implications for the development of an H pylori vaccine.