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Probst V, Shahoud F, Osborne AF, Alvarez A, Maraqa N, Mirza A. Report of Haemophilus Influenzae serotype a intracranial infections in older children. Pediatr Investig 2023; 7:132-136. [PMID: 37324595 PMCID: PMC10262899 DOI: 10.1002/ped4.12369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 01/03/2023] [Indexed: 06/17/2023] Open
Abstract
Introduction Haemophilus influenzae (Hi) is subdivided into typeable (a-f) and non-typeable groups. Hi serotype b (Hib) has historically been one of the important pathogens responsible for invasive infection. However, after widespread Hib vaccination, the emergence of other Hi serotypes, specifically Hi serotype a (Hia), was noted during the last few decades, mostly in children younger than 5 years of age. Case presentation We present two cases of severe intracranial infections with detected Hia in patients > 5 years of age within a short time frame and within the same geographic area. Conclusion Epidemiological studies and surveillance on Hia-related illnesses in all age groups worldwide are needed to better understand the clinical and epidemiological characteristics of Hia. This can establish a platform to develop a candidate vaccine against Hia that might protect children of all ages.
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Affiliation(s)
- Varvara Probst
- Department of PediatricsUniversity of Florida College of Medicine‐JacksonvilleJacksonvilleFloridaUSA
| | - Fadi Shahoud
- Department of PediatricsUniversity of Florida College of Medicine‐JacksonvilleJacksonvilleFloridaUSA
- Department of PediatricsDivision of Infectious Diseases and ImmunologyUniversity of Florida College of Medicine‐JacksonvilleJacksonvilleFloridaUSA
| | - Aaron Fletcher Osborne
- Department of PediatricsUniversity of Florida College of Medicine‐JacksonvilleJacksonvilleFloridaUSA
- Department of PediatricsDivision of Infectious Diseases and ImmunologyUniversity of Florida College of Medicine‐JacksonvilleJacksonvilleFloridaUSA
| | - Ana Alvarez
- Department of PediatricsUniversity of Florida College of Medicine‐JacksonvilleJacksonvilleFloridaUSA
- Department of PediatricsDivision of Infectious Diseases and ImmunologyUniversity of Florida College of Medicine‐JacksonvilleJacksonvilleFloridaUSA
| | - Nizar Maraqa
- Department of PediatricsDivision of Infectious Diseases and ImmunologyUniversity of Florida College of Medicine‐JacksonvilleJacksonvilleFloridaUSA
| | - Ayesha Mirza
- Department of PediatricsUniversity of Florida College of Medicine‐JacksonvilleJacksonvilleFloridaUSA
- Department of PediatricsDivision of Infectious Diseases and ImmunologyUniversity of Florida College of Medicine‐JacksonvilleJacksonvilleFloridaUSA
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Russo DO, Torres BR, Romanelli RMC, Rocha FSV, Viegas ECC, Diniz LMO. Haemophilus influenzae Serotype a as a Cause of Meningitis in Children in Brazil. Pediatr Infect Dis J 2022; 41:108-11. [PMID: 35017451 DOI: 10.1097/INF.0000000000003391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Since the introduction of Haemophilus influenzae type b vaccines, invasive disease due to Haemophilus influenzae serotype a (Hia) has been reported with increasing frequency. METHODS This study is based on hospital-based surveillance for Hia meningitis over a 5-year period. RESULTS Thirty-five patients with H. influenzae meningitis were hospitalized and 12 were serotype a. Hia was detected in blood and cerebrospinal fluid by culture or reverse transcription polymerase chain reaction. Patients' median age was 10 months, 7 (58%) boys and 5 (41%) girls. Ten (83%) children had received at least 1 vaccine dose against Haemophilus influenzae type b. All patients were treated with ceftriaxone for a median period of 11 days. The main complications described were empyema in 5 (41%) and seizures in 3 (25%) patients. Two (16.6%) patients died due to cerebral damage and shock. CONCLUSIONS Invasive disease due to Hia affecting young children accounts for considerable morbidity and mortality.
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McTaggart LR, Cronin K, Seo CY, Wilson S, Patel SN, Kus JV. Increased Incidence of Invasive Haemophilus influenzae Disease Driven by Non-Type B Isolates in Ontario, Canada, 2014 to 2018. Microbiol Spectr 2021; 9:e0080321. [PMID: 34612671 DOI: 10.1128/Spectrum.00803-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Haemophilus influenzae can cause serious invasive disease. We report the epidemiology and antimicrobial susceptibility of invasive H. influenzae in Ontario, Canada, from 2014 to 2018 from laboratory-based data. Blood was the most common specimen source (89.5%). Consistent with widespread vaccination against serotype b (Hib), the incidence of Hib in Ontario remained low (0.04 cases per 100,000 population). H. influenzae disease primarily afflicted those <1 and ≥65 years of age. From 2014 to 2018, cases of invasive H. influenzae increased 5.6%, from 1.67 to 2.06 cases per 100,000 population, the majority of which were attributed to a 7.6% increase in the incidence of H. influenzae in those ≥65 years old. H. influenzae disease was primarily caused by nontypeable H. influenzae (NTHi) (74.2%) and, to a much lesser extent, serotype a (Hia) (8.9%) and serotype f (Hif) (10.2%). Serotype-dependent trends in antimicrobial susceptibility were observed. Hia and Hif isolates were predominantly susceptible to all antibiotics tested, while 27.2% of NTHi isolates were nonsusceptible to ampicillin. Resistance to ceftriaxone and meropenem, first-line antibiotics for invasive disease treatment, was nonexistent. The incidence of invasive H. influenzae in Ontario is increasing. The incidence and antimicrobial susceptibility of all serotypes and nontypeable H. influenzae should be monitored. IMPORTANCE H. influenzae can cause serious invasive, life-threatening disease and is considered 1 of 12 priority pathogens by the World Health Organization. Widespread vaccination against H. influenzae serotype b (Hib) has resulted in very low incidence of Hib in Ontario and other regions that have vaccination programs. However, the epidemiology of non-Hib serotypes and nontypeable H. influenzae (NTHi) remains poorly understood. Here, we describe the epidemiology of all invasive H. influenzae isolates (N = 1,338) received by our laboratory over the 5-year period and report on the antimicrobial susceptibility patterns by serotype. Overall, we observed an increase in the incidence of invasive disease over the study period, primarily driven by NTHi. Serotype-dependent trends in antimicrobial susceptibility were also observed. This work contributes to the global understanding of H. influenzae epidemiology and antimicrobial resistance and is additionally important for further vaccine planning initiatives.
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Almuzam S, Lin D, Wong G, Isaacs D, Huynh J. Non-vaccine Haemophilus influenzae type a epiglottitis. J Paediatr Child Health 2021; 57:1133-1135. [PMID: 32861222 DOI: 10.1111/jpc.15146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 07/30/2020] [Accepted: 08/11/2020] [Indexed: 11/27/2022]
Affiliation(s)
- Sulaiman Almuzam
- Department of Infectious Diseases and Microbiology, The Children's Hospital at Westmead, Sydney, New South Wales, Australia
| | - Daniel Lin
- Department of Paediatrics, Blacktown and Mount Druitt Hospital, Sydney, New South Wales, Australia
| | - Gail Wong
- Department of Anaesthesia, The Children's Hospital at Westmead, Sydney, New South Wales, Australia
| | - David Isaacs
- Department of Infectious Diseases and Microbiology, The Children's Hospital at Westmead, Sydney, New South Wales, Australia.,University of Sydney, The Children's Hospital at Westmead, Sydney, New South Wales, Australia
| | - Julie Huynh
- Department of Infectious Diseases and Microbiology, The Children's Hospital at Westmead, Sydney, New South Wales, Australia.,Oxford University Clinical Research Unit, Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam
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Bozio CH, Blain A, Edge K, Farley MM, Harrison LH, Poissant T, Schaffner W, Scheuer T, Torres S, Triden L, Briere E, Oliver SE. Clinical characteristics and adverse clinical outcomes of invasive Haemophilus influenzae serotype a cases - United States, 2011-2015. Clin Infect Dis 2020; 73:e3670-e3676. [PMID: 32668450 DOI: 10.1093/cid/ciaa990] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Incidence of invasive disease due to H. influenzae serotype a (Hia) increased an average of 13% annually from 2002-2015. We described clinical characteristics and adverse clinical outcomes of U.S. invasive Hia cases detected through multi-state surveillance during 2011-2015. METHODS Medical record data were abstracted for cases reported in eight jurisdictions conducting active population- and laboratory-based surveillance for invasive Hia disease across the United States. Isolates from sterile sites were serotyped by real-time polymerase chain reaction. Adverse clinical outcomes were defined as any possible complication of meningitis, bacteremic pneumonia, or bacteremia (including hearing loss, developmental delay, and speech delay, but excluding death), and were assessed at hospital discharge and one-year post-disease onset. RESULTS During 2011-2015, 190 Hia cases were reported to the eight participating sites; 169 (88.9%) had data abstracted. Many patients were aged <5 years (42.6%) or ≥65 years (20.7%). Meningitis was the most common clinical presentation among <1 year olds (71.4%); bacteremic pneumonia was the most common presentation among persons aged ≥50 years (78.7%). Overall, 95.9% of patients were hospitalized: among those hospitalized, 47.5% were admitted to an intensive care unit, and 6.2% died during hospitalization. At hospital discharge and one-year post-disease onset, adverse outcomes were identified in 17.7% and 17.8% of patients overall, and in 43.9% and 48.5% of patients with meningitis (primarily children). CONCLUSIONS Hia infection can cause severe disease requiring hospitalization and may also cause short- and long-term adverse clinical outcomes, especially among children. Novel vaccines could prevent morbidity and mortality.
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Affiliation(s)
- Catherine H Bozio
- Epidemic Intelligence Service, Centers for Disease Control and Prevention (CDC), Atlanta, GA.,National Center for Immunization and Respiratory Diseases, CDC, Atlanta, GA
| | - Amy Blain
- National Center for Immunization and Respiratory Diseases, CDC, Atlanta, GA
| | - Karen Edge
- Colorado Department of Public Health and Environment, Colorado
| | - Monica M Farley
- Emory University School of Medicine, Atlanta, GA.,Atlanta VA Medical Center, Atlanta, GA
| | - Lee H Harrison
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | | | | | - Tara Scheuer
- California Emerging Infections Program, Oakland, CA
| | | | - Lori Triden
- Minnesota Department of Health, St. Paul, MN
| | - Elizabeth Briere
- National Center for Immunization and Respiratory Diseases, CDC, Atlanta, GA
| | - Sara E Oliver
- National Center for Immunization and Respiratory Diseases, CDC, Atlanta, GA
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6
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Tsang RSW, Shuel M, Ahmad T, Hayden K, Knox N, Van Domselaar G, Hoang L, Tyrrell GJ, Minion J, Van Caeseele P, Kus JV, Ulanova M, Lefebvre B, Haldane D, Garceau R, German G, Zahariadis G, Hanley B, Kandola K, Patterson M. Whole genome sequencing to study the phylogenetic structure of serotype a Haemophilus influenzae recovered from patients in Canada. Can J Microbiol 2019; 66:99-110. [PMID: 31661630 DOI: 10.1139/cjm-2019-0406] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study examined the phylogenetic structure of serotype a Haemophilus influenzae (Hia) isolates recovered from patients in Canada. Hia isolates from 490 separate patients and an American Type Culture Collection (ATCC) strain were analyzed by multilocus sequence typing (MLST), with 18 different sequence types (STs) identified. Most (85.7%) Hia patient isolates were typed as ST-23 and another 12.7% belonged to 14 different STs with 6, 5, or 4 MLST gene loci related to ST-23 (ST-23 complex). Core genome single-nucleotide variation phylogeny (SNVPhyl) on whole genome sequence (WGS) data of 121 Hia patient isolates representing all identified STs and the ATCC strain revealed 2 phylogenetic populations, with all the ST-23 complex isolates within 1 population. The other phylogenetic population contained only the ATCC strain and 3 patient isolates. Concatenated hitABC sequences retrieved from WGS data and analyzed by MEGA (Molecular Evolutionary Genetic Analysis) alignment confirmed the phylogeny obtained by SNVPhyl. The sodC gene was found only in isolates in the minor phylogenetic population. The 2 phylogenetic populations of the Canadian Hia isolates are similar to the 2 clonal divisions described for serotype b H. influenzae. Combining MLST, core SNVPhyl, and hitABC gene sequence alignment showed that most (99.4%) Canadian Hia patient isolates belonged to 1 major phylogenetic population.
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Affiliation(s)
- Raymond S W Tsang
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Michelle Shuel
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Tauqeer Ahmad
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Kristy Hayden
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Natalie Knox
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada.,Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Gary Van Domselaar
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada.,Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Linda Hoang
- BC Public Health Microbiology and Reference Laboratory, Vancouver, British Columbia, Canada
| | | | - Jessica Minion
- Roy Romanow Provincial Laboratory, Regina, Saskatchewan, Canada
| | | | - Julianne V Kus
- Public Health Ontario, Toronto, Ontario, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Marina Ulanova
- Northern Ontario School of Medicine, Thunder Bay, Ontario, Canada
| | - Brigitte Lefebvre
- Laboratoire de santé publique du Québec, Institut national de santé publique du Québec, Sainte-Anne-de-Bellevue, Quebec, Canada
| | - David Haldane
- Nova Scotia Health Authority, Halifax, Nova Scotia, Canada.,Dalhousie University, Halifax, Nova Scotia, Canada
| | - Richard Garceau
- Communicable Disease Control Unit, Department of Health, Government of New Brunswick, Fredericton, New Brunswick, Canada
| | - Greg German
- Department of Health, Government of Prince Edward Island, Charlottetown, Prince Edward Island, Canada
| | - George Zahariadis
- Provincial Public Health Laboratory, Eastern Health Microbiology Services, St. John's, Newfoundland and Labrador, Canada.,Department of Laboratory Medicine, Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador, Canada
| | - Brendan Hanley
- Department of Health and Social Services, Government of Yukon, Whitehorse, Yukon, Canada
| | - Kami Kandola
- Department of Health and Social Services, Government of Northwest Territories, Yellowknife, Northwest Territories, Canada
| | - Michael Patterson
- Department of Health, Government of Nunavut, Iqaluit, Nunavut, Canada
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Månsson V, Gilsdorf JR, Kahlmeter G, Kilian M, Kroll JS, Riesbeck K, Resman F. Capsule Typing of Haemophilus influenzae by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry. Emerg Infect Dis 2019; 24:443-452. [PMID: 29460728 PMCID: PMC5823330 DOI: 10.3201/eid2403.170459] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Encapsulated Haemophilus influenzae strains belong to type-specific genetic lineages. Reliable capsule typing requires PCR, but a more efficient method would be useful. We evaluated capsule typing by using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. Isolates of all capsule types (a−f and nontypeable; n = 258) and isogenic capsule transformants (types a−d) were investigated. Principal component and biomarker analyses of mass spectra showed clustering, and mass peaks correlated with capsule type-specific genetic lineages. We used 31 selected isolates to construct a capsule typing database. Validation with the remaining isolates (n = 227) showed 100% sensitivity and 92.2% specificity for encapsulated strains (a−f; n = 61). Blinded validation of a supplemented database (n = 50) using clinical isolates (n = 126) showed 100% sensitivity and 100% specificity for encapsulated strains (b, e, and f; n = 28). MALDI-TOF mass spectrometry is an accurate method for capsule typing of H. influenzae.
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8
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Plumb ID, Lecy D, Singleton R, Engel MC, Hirschfeld M, Keck JW, Klejka J, Rudolph KM, Hennessy TW, Bruce MG. Invasive Haemophilus influenzae Serotype a Infection in Children: Clinical Description of an Emerging Pathogen-Alaska, 2002-2014. Pediatr Infect Dis J 2018; 37:298-303. [PMID: 29189672 PMCID: PMC6362456 DOI: 10.1097/inf.0000000000001764] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Invasive infections from Haemophilus influenzae serotype a (Hia) have been reported with increasing frequency, especially among indigenous populations. However, there are limited population-based studies of clinical severity. We studied invasive Hia infections in Alaska to determine clinical characteristics, mortality and sequelae. METHODS We defined an invasive Hia infection as the first detection of Hia from a usually sterile site in a child <10 years of age from Alaska. We identified cases using the Alaska Invasive Bacterial Diseases Surveillance System and reviewed medical charts up to 2 years after reported illness. RESULTS We identified invasive Hia infections in 36 children, 28 (78%) <1 year old, 34 (94%) living in an Alaskan village and 25 (69%) without documented underlying illness. Overlapping clinical presentations included meningitis in 15 children (42%); bacteremia and pneumonia in 10 children (28%); and bone, joint or soft tissue infections in 10 children (22%). In 4 other children, no source of invasive infection was identified. Intensive care was provided for 11 children (31%); 12 children (33%) required surgical intervention. One year after infection, 4 children (11%) had died from Hia, and 5 children (14%) had ongoing neurologic sequelae. CONCLUSIONS Invasive Hia infections in Alaska occurred predominantly in Alaska Native infants in rural communities. Although one-third of children had preexisting conditions, most cases occurred without known comorbidity. Clinical syndromes were frequently severe. One year after infection, 1 in 4 children had either died or had neurologic sequelae. An effective vaccine would prevent significant morbidity and mortality in affected populations.
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9
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Shoukat A, Van Exan R, Moghadas SM. Cost-effectiveness of a potential vaccine candidate for Haemophilus influenzae serotype 'a'. Vaccine 2018; 36:1681-1688. [PMID: 29459062 DOI: 10.1016/j.vaccine.2018.01.047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 01/12/2018] [Accepted: 01/17/2018] [Indexed: 02/06/2023]
Abstract
The preceding decade has witnessed the emergence of severe community-acquired acute infections caused by Haemophilus influenzae serotype a (Hia), with alarming incidence rates in North America, particularly among indigenous populations. The remarkable success of Hib conjugate vaccine over the past 20 years signify the development of an Hia vaccine candidate as a prevention measure to reduce the incidence of invasive Hia disease. However, quantifications of the long-term epidemiologic and economic impacts of vaccination are needed to inform decision on investment in Hia vaccine development and immunization programs. We sought to evaluate the cost-effectiveness of an Hia vaccine with a similar routine infant immunization schedules currently in practice for Hib in Canada. We developed and parameterized an agent-based simulation model using age-specific incidence rates reported for Nunavut, a Canadian territory with predominantly aboriginal populations. Our results, based on statistical analyses of the incremental cost-effectiveness ratio, show that an Hia conjugate vaccine is highly cost-effective. Sustaining an immunization program with vaccine coverages of 77% for primary series and 93% for booster dose over a 10-year period reduces the incidence of invasive disease by 63.8% on average from 9.97 to 3.61 cases, per 100,000 population. The overall costs of disease management in year 10 are reduced by 53.4% from CDN $1.863 million (95% CI: $1.229-$2.519 M) to CDN $0.868 million (95% CI: $0.627-$1.120 M). The findings suggest an important role for a conjugate vaccine in managing Hia disease as a growing public health threat.
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Affiliation(s)
- Affan Shoukat
- Agent-Based Modelling Laboratory, York University, Toronto, Ontario M3J 1P3, Canada.
| | - Robert Van Exan
- Immunization & Policy Translation, 16 Fire Route 105, Trent Lakes, Ontario K0M 1A0, Canada
| | - Seyed M Moghadas
- Agent-Based Modelling Laboratory, York University, Toronto, Ontario M3J 1P3, Canada
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10
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Cox AD, Williams D, Cairns C, St Michael F, Fleming P, Vinogradov E, Arbour M, Masson L, Zou W. Investigating the candidacy of a capsular polysaccharide-based glycoconjugate as a vaccine to combat Haemophilus influenzae type a disease: A solution for an unmet public health need. Vaccine 2017; 35:6129-6136. [PMID: 28951087 DOI: 10.1016/j.vaccine.2017.09.055] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 09/17/2017] [Indexed: 11/29/2022]
Abstract
After the introduction of the glycoconjugate vaccine based upon the capsular polysaccharide ofHaemophilus influenzaetype b in the mid 1980s there was a remarkable decrease in the number of invasive cases reported for this organism. Since the 1990s several groups have observed the emergence ofHaemophilus influenzaetype a (Hia), especially in indigenous communities in the northern regions of Canada and Alaska, to a stage where a solution is warranted to prevent further unnecessary deaths due to this pathogen. A glycoconjugate vaccine solution based upon the type a capsular polysaccharide (CPS) was investigated pre-clinically in an effort to illustrate the proof of concept for this approach. In this study we describe the growth of Hia and the isolation, purification and conjugation of the CPS to several carrier proteins. The resulting glycoconjugates were immunised in mice and rabbits provoking sera that facilitated bactericidal killing against all type a strains that we tested. This study has illustrated the pre-clinical proof of concept of a glycoconjugate vaccine based on the CPS of Hia asa solution to this emerging disease.
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Affiliation(s)
- Andrew D Cox
- Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, ON K1A 0R6, Canada.
| | - Dean Williams
- Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, ON K1A 0R6, Canada
| | - Chantelle Cairns
- Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, ON K1A 0R6, Canada
| | - Frank St Michael
- Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, ON K1A 0R6, Canada
| | - Perry Fleming
- Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, ON K1A 0R6, Canada
| | - Evgeny Vinogradov
- Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, ON K1A 0R6, Canada
| | - Mélanie Arbour
- Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, ON K1A 0R6, Canada
| | - Luke Masson
- Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, ON K1A 0R6, Canada
| | - Wei Zou
- Vaccine Program, Human Health Therapeutics Portfolio, National Research Council, Ottawa, ON K1A 0R6, Canada
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11
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Eton V, Schroeter A, Kelly L, Kirlew M, Tsang RSW, Ulanova M. Epidemiology of invasive pneumococcal and Haemophilus influenzae diseases in Northwestern Ontario, Canada, 2010-2015. Int J Infect Dis 2017; 65:27-33. [PMID: 28951105 DOI: 10.1016/j.ijid.2017.09.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 09/10/2017] [Accepted: 09/15/2017] [Indexed: 10/18/2022] Open
Abstract
INTRODUCTION North American indigenous populations experience a high burden of invasive bacterial infections. Because Streptococcus pneumoniae and Haemophilus influenzae have multiple antigenic variants, the existing vaccines cannot prevent all cases. This study addresses the current epidemiology of invasive H. influenzae and pneumococcal disease (IPD) in a region of Northwestern Ontario, Canada with a relatively high (82%) indigenous population. METHODS Data were retrieved from a retrospective chart review at a hospital servicing a population of 29000 (82% indigenous), during January 2010-July 2015. RESULTS Ten cases of invasive H. influenzae disease and 37 cases of IPD were identified. The incidence of both in the study population (6.3 and 23.1/100000/year, respectively) exceeded national rates (1.6 and 9.0/100000/year). H. influenzae serotype a (Hia) was the most common (50%), followed by non-typeable H. influenzae (20%). In adults, 77% of IPD cases were caused by serotypes included in the 23-valent pneumococcal polysaccharide vaccine. All paediatric IPD cases were caused by serotypes not included in the 13-valent pneumococcal conjugate vaccine. The case-fatality rate was 10% for invasive H. influenzae and 2.7% for IPD. Most cases exhibited substantial co-morbidity. CONCLUSIONS In Northwestern Ontario, the incidence of invasive Hia disease exceeds that of H. influenzae type b (Hib) in the pre-Hib vaccine era. This provides strong support for the development of a new Hia vaccine. Improved pneumococcal vaccination of high-risk adults in the region is warranted.
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Affiliation(s)
- Vic Eton
- Northern Ontario School of Medicine, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1, Canada.
| | - Annette Schroeter
- Sioux Lookout Meno Ya Win Health Centre, Sioux Lookout, Ontario, Canada
| | - Len Kelly
- Sioux Lookout Meno Ya Win Health Centre, Sioux Lookout, Ontario, Canada
| | - Michael Kirlew
- Sioux Lookout Meno Ya Win Health Centre, Sioux Lookout, Ontario, Canada; Northern Ontario School of Medicine, Sioux Lookout, Ontario, Canada
| | - Raymond S W Tsang
- Vaccine Preventable Bacterial Diseases, National Microbiology Laboratory, Winnipeg, Manitoba, Canada
| | - Marina Ulanova
- Northern Ontario School of Medicine, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1, Canada; Lakehead University, Thunder Bay, Ontario, Canada
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12
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Tsang RSW, Ulanova M. The changing epidemiology of invasive Haemophilus influenzae disease: Emergence and global presence of serotype a strains that may require a new vaccine for control. Vaccine 2017; 35:4270-4275. [PMID: 28666758 DOI: 10.1016/j.vaccine.2017.06.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 05/23/2017] [Accepted: 06/01/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND More than two decades after the implementation of the Hib conjugate vaccine in North America, Haemophilus influenzae serotype a (Hia) has emerged as a significant cause of invasive disease in Indigenous communities. However, little is known about the global presence of this pathogen. METHODS We interrogated the H. influenzae Multi-Locus Sequence Typing (MLST) website (https://pubmlst.org/hinfluenzae/) by selecting for serotype a records. We also updated our previous literature review on this subject matter. RESULTS Hia has been reported from at least 35 countries on six major continents. However, most Hia diseases were associated with Indigenous communities. Clonal analysis identified two clonal populations with one typified as ST-23 responsible for most invasive disease in North America and being the predominant clone described on the H. influenzae MLST website. Incidence of invasive Hia disease in Indigenous communities in North America are similar to the rates of Hib disease reported prior to the Hib conjugate vaccine era. Hia causes severe clinical diseases, such as meningitis, septicaemia, pneumonia, and septic arthritis with case-fatality rates between 5.6% and 33% depending on the age of the patient and the genetic makeup of the Hia strain. CONCLUSION Although invasive Hia disease can be found globally, the current epidemiological data suggest that this infection predominantly affects Indigenous communities in North America. The clinical disease of Hia and the clonal nature of the bacteria resemble that of Hib. The high incidence of invasive Hia disease in Indigenous communities, along with potential fatality and severe sequelae causing long-term disability in survivors, may support the development of a new Hia conjugate vaccine for protection against this infection similar in design to the one introduced in the 1990s to control invasive Hib disease.
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Affiliation(s)
- Raymond S W Tsang
- Vaccine Preventable Bacterial Diseases, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada.
| | - Marina Ulanova
- Northern Ontario School of Medicine, Lakehead University, Thunder Bay, Ontario, Canada
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Tsang RS, Proulx J, Hayden K, Shuel M, Lefebvre B, Boisvert A, Moore D. Characteristics of invasive Haemophilus influenzae serotype a (Hia) from Nunavik, Canada and comparison with Hia strains in other North American Arctic regions. Int J Infect Dis 2017; 57:104-7. [DOI: 10.1016/j.ijid.2017.02.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 02/02/2017] [Accepted: 02/05/2017] [Indexed: 11/21/2022] Open
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Koch A, Bruce MG, Ladefoged K. Arctic and Antarctica. Infect Dis (Lond) 2017. [DOI: 10.1002/9781119085751.ch27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Anders Koch
- Department of Epidemiology Research, Statens Serum Institut and Department of Infectious Diseases; Rigshospitalet University Hospital; Copenhagen Denmark
| | - Michael G. Bruce
- Arctic Investigations Program; DPEI, NCEZID, CDC, Anchorage; Alaska USA
| | - Karin Ladefoged
- Department of Internal Medicine; Queen Ingrid's Hospital; Nuuk Greenland
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Abstract
OBJECTIVES This study reviews how social and environmental issues affect health in Arctic populations and describes infectious disease surveillance in Arctic Nations with a special focus on the activities of the International Circumpolar Surveillance (ICS) project. METHODS We reviewed the literature over the past 2 decades looking at Arctic living conditions and their effects on health and Arctic surveillance for infectious diseases. RESULTS In regards to other regions worldwide, the Arctic climate and environment are extreme. Arctic and sub-Arctic populations live in markedly different social and physical environments compared to those of their more southern dwelling counterparts. A cold northern climate means people spending more time indoors, amplifying the effects of household crowding, smoking and inadequate ventilation on the person-to-person spread of infectious diseases. The spread of zoonotic infections north as the climate warms, emergence of antibiotic resistance among bacterial pathogens, the re-emergence of tuberculosis, the entrance of HIV into Arctic communities, the specter of pandemic influenza or the sudden emergence and introduction of new viral pathogens pose new challenges to residents, governments and public health authorities of all Arctic countries. ICS is a network of hospitals, public health agencies, and reference laboratories throughout the Arctic working together for the purposes of collecting, comparing and sharing of uniform laboratory and epidemiological data on infectious diseases of concern and assisting in the formulation of prevention and control strategies (Fig. 1). In addition, circumpolar infectious disease research workgroups and sentinel surveillance systems for bacterial and viral pathogens exist. CONCLUSIONS The ICS system is a successful example of collaborative surveillance and research in an extreme environment.
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Affiliation(s)
- M Bruce
- Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, AK, USA.
| | - T Zulz
- Arctic Investigations Program, Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Anchorage, AK, USA
| | - A Koch
- Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark
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Konini A, Nix E, Ulanova M, Moghadas SM. Dynamics of naturally acquired antibody against Haemophilus influenzae type a capsular polysaccharide in a Canadian Aboriginal population. Prev Med Rep 2016; 3:145-50. [PMID: 27419007 PMCID: PMC4929236 DOI: 10.1016/j.pmedr.2016.01.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Severe infections caused by Haemophilus influenzae type a (Hia) have reached alarming rates in some Canadian Aboriginal communities. We sought to estimate the frequency of exposure to this pathogen and timelines for boosting protective antibodies. We developed a model of secondary antigenic challenge (natural exposure), and used data for anti-Hia antibodies in serum samples of healthy and immunocompromised adults in a population of Northwestern Ontario, Canada. We parameterized the model with available estimates from previous studies for the decay rate of antibody and its protective levels against both Hia carriage and invasive disease. Simulations were initialized using antibody concentrations from data. We investigated both the duration of immunity without secondary antigenic challenge and the average time between subsequent exposures to Hia. When there was no new natural exposure, serum antibody concentrations in healthy Aboriginal individuals decreased below the level (1 μg/ml) assumed for protection against invasive Hia disease 3 years after primary exposure. This period was shorter (about 2 years) for Aboriginal individuals suffering from chronic renal failure. We estimated that a new antigenic challenge occurs once in 5 and 2 years for healthy and immunocompromised Aboriginal individuals, respectively. More frequent natural exposure was required to maintain protective antibody levels for non-Aboriginal individuals compared to Aboriginal individuals. The findings suggest that frequent boosting of natural immunity is required to maintain the anti-Hia antibody levels protecting against invasive Hia disease, particularly in individuals with underlying medical conditions. This information has important implications for immunization when an anti-Hia vaccine becomes available. Frequent natural exposure to Hia is required to maintain protective immunity. Epigenetic factors may affect formation of natural immunity in Aboriginal people. Further data pertaining to immunological correlates of Hia are needed. Modeling can inform timelines of boosting immunity and vaccination policies.
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Affiliation(s)
- Angjelina Konini
- Agent-Based Modelling Laboratory, York University, 4700 Keele St., Toronto, Ontario M3J 1P3, Canada
- Corresponding author.
| | - Eli Nix
- Northern Ontario School of Medicine, Lakehead University, Thunder Bay, Ontario, Canada
| | - Marina Ulanova
- Northern Ontario School of Medicine, Lakehead University, Thunder Bay, Ontario, Canada
| | - Seyed M. Moghadas
- Agent-Based Modelling Laboratory, York University, 4700 Keele St., Toronto, Ontario M3J 1P3, Canada
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Abstract
BACKGROUND Northern populations were at a high risk of developing invasive bacterial diseases (IBDs). Since the last published study that described IBDs in Northern Canada, a number of vaccines against some bacterial pathogens have been introduced into the routine childhood immunization schedule. OBJECTIVE To describe the epidemiology of IBDs in Northern Canada from 2006 to 2013. METHODS Data for 5 IBDs (invasive pneumococcal disease (IPD), invasive Haemophilus influenzae disease (Hi), invasive Group A streptococcal disease (iGAS), invasive meningococcal disease (IMD) and invasive Group B streptococcal disease (GBS)) were extracted from the International Circumpolar Surveillance (ICS) program and the Canadian Notifiable Diseases Surveillance System. Incidence rates were calculated per 100,000 population per year. RESULTS During the study period, the incidence rates of IPD ranged from 16.84-30.97, iGAS 2.70-17.06, Hi serotype b 0-2.78, Hi non-b type 2.73-8.53, and IMD 0-3.47. Except for IMD and GBS, the age-standardized incidence rates of other diseases in Northern Canada were 2.6-10 times higher than in the rest of Canada. Over the study period, rates decreased for IPD (p=0.04), and iGAS (p=0.01), and increased for Hi type a (Hia) (p=0.004). Among IPD cases, the proportion of pneumococcal conjugate vaccine (PCV)7 serotypes decreased (p=0.0004) over the study period. Among Hi cases, 69.8% were Hia and 71.6% of these were in children under than 5 years. Of 13 IMD cases, 8 were serogroup B and 2 of them died. CONCLUSION Northern population in Canada, especially infants and seniors among First Nations and Inuit, are at a high risk of IPD, Hi and iGAS. Hia is the predominant serotype in Northern Canada.
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Affiliation(s)
- YA Li
- Infectious Disease Prevention and Control Branch, Public Health Agency of Canada Ottawa, ON
| | - I Martin
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MN
| | - R Tsang
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MN
| | - SG Squires
- Infectious Disease Prevention and Control Branch, Public Health Agency of Canada Ottawa, ON
| | - W Demczuk
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MN
| | - S Desai
- Infectious Disease Prevention and Control Branch, Public Health Agency of Canada Ottawa, ON
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Konini A, Kang M, Moghadas SM. Simulating Immune Interference on the Effect of a Bivalent Glycoconjugate Vaccine against Haemophilus influenzae Serotypes "a" and "b". Can J Infect Dis Med Microbiol 2016; 2016:5486869. [PMID: 27366171 DOI: 10.1155/2016/5486869] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 11/12/2015] [Indexed: 11/17/2022]
Abstract
Objective. We sought to evaluate the immune responses to a bivalent Haemophilus influenzae glycoconjugate vaccine against serotypes “a” (Hia) and “b” (Hib) in the presence of the preexisting immunity to Hib. Methods. We developed a stochastic simulation model of humoral immune response to investigate the antigenic challenge of a bivalent combined glycoconjugate vaccine and a bivalent unimolecular glycoconjugate vaccine. We compared simulation outcomes in the absence of any preexisting immunity with an already primed immune response having specific memory B cells and/or anti-Hib antibodies. Results. The simulation results show that the preexisting immune responses to Hib or carrier protein (CP) may significantly impede the production of anti-Hia antibodies by a unimolecular vaccine. In contrast, the production of anti-Hia antibodies using a combined vaccine is inhibited only in the presence of CP immune responses. Conclusions. Preexisting immunity to Hib and CP may play a critical role in the development of immune responses against Hia or Hib using bivalent combined and unimolecular vaccine formulations. Our results suggest that a bivalent combined glycoconjugate vaccine with a carrier protein not previously used in Hib conjugate vaccines may be an effective formulation for generating immune responses to protect against both Hib and Hia infections.
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Boisvert AA, Moore D. Invasive disease due to Haemophilus influenzae type A in children in Canada's north: A priority for prevention. Can J Infect Dis Med Microbiol 2015; 26:291-2. [PMID: 26744583 DOI: 10.1155/2015/613820] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Desai S, Jamieson FB, Patel SN, Seo CY, Dang V, Fediurek J, Navaranjan D, Deeks SL. The Epidemiology of Invasive Haemophilus influenzae Non-Serotype B Disease in Ontario, Canada from 2004 to 2013. PLoS One 2015; 10:e0142179. [PMID: 26569613 PMCID: PMC4646341 DOI: 10.1371/journal.pone.0142179] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 10/19/2015] [Indexed: 12/29/2022] Open
Abstract
Background Since the widespread use of Haemophilus influenzae (Hi) type b (Hib) vaccines among children aged <5 years, an increase in invasive non-Hib disease incidence has been reported internationally. We sought to describe the epidemiology of invasive non-Hib disease in Ontario, Canada (population ~13.5 million). Methods Confirmed invasive non-Hib cases (non-typeable [NTHi] and serotypes a, c, d, e, and f) were obtained from the provincial laboratory data system from 2004–2013. Data were deterministically linked to the provincial reportable disease system to provide further case information. Antibiotic resistance data were analysed separately from 2010–2014. Descriptive analyses included incidence rates, age group, serotype, site of specimen collection and resistance patterns; ethnicity data were not available. Temporal trends were evaluated by Poisson regression and p-values <0.05 were considered significant. Results A total of 1307 cases of invasive non-Hib disease were included, increasing from 0.67 cases to 1.60 cases /100,000 from 2004 to 2013. Significant increases in the incidence of NTHi (0.50 to 1.28 cases/100 000 population), Hia (0.02 to 0.08 cases/100, 000) and Hif (0.13 to 0.18 cases/100, 000 population) were seen. Among persons aged 40–64 years, 3 Hi strains significantly increased over time; NTHi (0.22 to 0.99 cases/100, 000), Hia (0.00 to 0.06 cases/100, 000) and Hif (0.05 to 0.21 cases/100, 000). Among persons aged 65–84 years, there was a significant increase of NTHi (1.62 to 3.14 cases/100, 000) and Hia (0.00 to 0.34 cases/100, 000). Among persons aged 85+ years, only NTHi significantly increased from 4.89 to 10.28 cases/100, 000). Antimicrobial resistance (AMR) to ampicillin and clarithromycin was seen in greater than 25% of isolates but AMR did not increase over the duration of this study. Conclusions The incidence of invasive non-Hib disease has increased over time; NTHi, Hif and Hia are emerging pathogens, and should be monitored.
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Affiliation(s)
- Shalini Desai
- Immunization and Vaccine Preventable Diseases Division, Public Health Ontario, Toronto, ON, Canada
- * E-mail:
| | - Frances B. Jamieson
- Public Health Ontario Laboratories, Public Health Ontario, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Samir N. Patel
- Public Health Ontario Laboratories, Public Health Ontario, Toronto, ON, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Chi Yon Seo
- Immunization and Vaccine Preventable Diseases Division, Public Health Ontario, Toronto, ON, Canada
| | - Vica Dang
- Public Health Ontario Laboratories, Public Health Ontario, Toronto, ON, Canada
| | - Jill Fediurek
- Immunization and Vaccine Preventable Diseases Division, Public Health Ontario, Toronto, ON, Canada
| | - Debeka Navaranjan
- Immunization and Vaccine Preventable Diseases Division, Public Health Ontario, Toronto, ON, Canada
| | - Shelley L. Deeks
- Immunization and Vaccine Preventable Diseases Division, Public Health Ontario, Toronto, ON, Canada
- Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada
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Nix EB, Williams K, Cox AD, St Michael F, Romero-Steiner S, Schmidt DS, McCready WG, Ulanova M. Naturally acquired antibodies against Haemophilus influenzae type a in Aboriginal adults, Canada. Emerg Infect Dis 2015; 21:273-9. [PMID: 25626129 PMCID: PMC4313637 DOI: 10.3201/eid2102.140722] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
High prevalence of invasive Hia disease among North American Aboriginal populations is more likely related to exposure than to inadequate immunity. In the post-Haemophilus influenzae type b (Hib) vaccine era that began in the 1980's, H. influenzae type a (Hia) emerged as a prominent cause of invasive disease in North American Aboriginal populations. To test whether a lack of naturally acquired antibodies may underlie increased rates of invasive Hia disease, we compared serum bactericidal activity against Hia and Hib and IgG and IgM against capsular polysaccharide between Canadian Aboriginal and non-Aboriginal healthy and immunocompromised adults. Both healthy and immunocompromised Aboriginal adults exhibited significantly higher bactericidal antibody titers against Hia than did non-Aboriginal adults (p = 0.042 and 0.045 respectively), with no difference in functional antibody activity against Hib. IgM concentrations against Hia were higher than IgG in most study groups; the inverse was true for antibody concentrations against Hib. Our results indicate that Aboriginal adults possess substantial serum bactericidal activity against Hia that is mostly due to IgM antibodies. The presence of sustained IgM against Hia suggests recent Hia exposure.
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Whyte K, Levett PN, Horsman GB, Chokani K, Hayden K, Shuel M, Tsang RSW. Recurrent invasive Haemophilus influenzae serotype a infection in an infant. ACTA ACUST UNITED AC 2015. [DOI: 10.7243/2052-6180-3-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Abstract
Disease surveillance can be used as an opportunity to determine priorities for research and the development of new therapeutics. This is evident in the work underway to develop a new vaccine to combat a serious invasive childhood disease: Haemophilus influenzae serotype a (Hia). Following the introduction of Hib vaccine into the routine childhood immunization schedule in Canada in the early 1990's, the Public Health Agency of Canada (PHAC) began to document the dropping rates of H influenzae serotype b (Hib) infection. However, invasive H. influenzae diseases due to non-Hib strains began to increase and in 2007, surveillance for invasive H. influenzae disease due to all serotypes as well as non-typeable strains was initiated. Current data suggests Hia is a cause of serious invasive disease, particularly in Aboriginal populations. Similar to Hib, Hia causes severe illnesses such as meningitis, sepsis and bacteremic pneumonia in young children under the age of five. Given the emerging threat due to Hia in Aboriginal populations in Canada, PHAC formed a partnership with the National Research Council of Canada (NRC) to investigate the potential of creating a capsular polysaccharide vaccine against Hia. At the present time, candidate vaccine seed strains have been identified and PHAC and the NRC are working with the Northern Ontario School of Medicine, the US Centers for Disease Control and Prevention and others. The goal of this research is to identify and prepare a candidate vaccine against Hia while increasing the understanding of how such a vaccine would improve the health of a vulnerable population.
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Affiliation(s)
- S Desai
- Center for Immunization and Respiratory Infectious Diseases, Public Health Agency of Canada, Ottawa, ON
| | - R Tsang
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB
| | - M St. Laurent
- Center for Immunization and Respiratory Infectious Diseases, Public Health Agency of Canada, Ottawa, ON
| | - A Cox
- Vaccine Program, Human Health Therapeutics, National Research Council of Canada, Ottawa, ON
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Affiliation(s)
| | - Raymond S. W. Tsang
- Vaccine Preventable Bacterial Diseases, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Frances B. Jamieson
- Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Canada
- Public Health Laboratories, Public Health Ontario, Toronto, Ontario, Canada
| | - Marina Ulanova
- Northern Ontario School of Medicine, Thunder Bay, Ontario, Canada
- Lakehead University, Thunder Bay, Ontario, Canada
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TSANG RSW, BRUCE MG, LEM M, BARRETO L, ULANOVA M. A review of invasive Haemophilus influenzae disease in the Indigenous populations of North America. Epidemiol Infect 2014; 142:1344-54. [PMID: 24598220 PMCID: PMC9151223 DOI: 10.1017/s0950268814000405] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 01/30/2014] [Accepted: 02/04/2014] [Indexed: 11/06/2022] Open
Abstract
Historically, the highest incidence rates of invasive Haemophilus influenzae disease in the world were found in North American and Australian Indigenous children. Although immunization against H. influenzae type b (Hib) led to a marked decrease in invasive Hib disease in countries where it was implemented, this disease has not been eliminated and its rates in Indigenous communities remain higher than in the general North American population. In this literature review, we examined the epidemiology of invasive H. influenzae disease in the pre-Hib vaccine era, effect of carriage on disease epidemiology, immune response to H. influenzae infection and Hib vaccination in Indigenous and Caucasian children, and the changing epidemiology after Hib conjugate vaccine has been in use for more than two decades in North America. We also explored reasons behind the continued high rates of invasive H. influenzae disease in Indigenous populations in North America. H. influenzae type a (Hia) has emerged as a significant cause of severe disease in North American Indigenous communities. More research is needed to define the genotypic diversity of Hia and the disease burden that it causes in order to determine if a Hia vaccine is required to protect the vulnerable populations.
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Affiliation(s)
- R. S. W. TSANG
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada
| | - M. G. BRUCE
- Arctic Investigations Program, Division of Preparedness and Emerging Infections, U.S. Centers for Disease Prevention and Control (CDC), Anchorage, AK, USA
| | - M. LEM
- Fraser Health Authority, Abbotsford, BC, Canada
| | - L. BARRETO
- Human Health Therapeutics Portfolio, National Research Council of Canada, Ottawa, ON, Canada
| | - M. ULANOVA
- Medical Sciences Division, Northern Ontario School of Medicine, Thunder Bay, ON, Canada
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Abstract
Haemophilus influenzae, particularly H influenzae serotype b (Hib), is an important pathogen that causes serious diseases like meningitis and septicaemia. Since the introduction of Hib conjugate vaccines in the 1990s, the epidemiology of invasive H influenzae disease has changed substantially, with most infections now caused by non-Hib strains. We discuss the importance of H influenzae serotype a (Hia) as a cause of serious morbidity and mortality and its global epidemiology, clinical presentation, microbiology, immunology, prevention, and control. Much like Hib, the capsule of Hia is an important virulence factor contributing to the development of invasive disease. Molecular typing of Hia has identified distinct clonal groups, with some linked to severe disease and high case-fatality rates. Similarities between Hia and Hib capsules, their clinical presentation, and immunology of infection suggest that a bivalent Hia-Hib capsular polysaccharide-protein conjugate vaccine could offer protection against these two important serotypes of H influenzae.
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Affiliation(s)
- Marina Ulanova
- Northern Ontario School of Medicine, Lakehead University, Thunder Bay, ON, Canada
| | - Raymond S W Tsang
- National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada.
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