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Martin LB, Tack B, Marchello CS, Sikorski MJ, Owusu-Dabo E, Nyirenda T, Mogasale V, Crump JA. Vaccine value profile for invasive non-typhoidal Salmonella disease. Vaccine 2024; 42:S101-S124. [PMID: 39003017 DOI: 10.1016/j.vaccine.2024.04.045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 04/12/2024] [Accepted: 04/14/2024] [Indexed: 07/15/2024]
Abstract
Invasive non-typhoidal Salmonella (iNTS) disease is an under-recognized high-burden disease causing major health and socioeconomic issues in sub-Saharan Africa (sSA), predominantly among immune-naïve infants and young children, including those with recognized comorbidities such as HIV infection. iNTS disease is primarily caused by Salmonella enterica serovar Typhimurium sequence type (ST) 313 and 'African-restricted clades' of Salmonella Enteritidis ST11 that have emerged across the African continent as a series of epidemics associated with acquisition of new antimicrobial resistance. Due to genotypes with a high prevalence of antimicrobial resistance and scarcity of therapeutic options, these NTS serovars are designated by the World Health Organization as a priority pathogen for research and development of interventions, including vaccines, to address and reduce NTS associated bacteremia and meningitis in sSA. Novel and traditional vaccine technologies are being applied to develop vaccines against iNTS disease, and the results of the first clinical trials in the infant target population should become available in the near future. The "Vaccine Value Profile" (VVP) addresses information related predominantly to invasive disease caused by Salmonella Enteritidis and Salmonella Typhimurium prevalent in sSA. Information is included on stand-alone iNTS disease candidate vaccines and candidate vaccines targeting iNTS disease combined with another invasive serotype, Salmonella Typhi, that is also common across sSA. Out of scope for the first version of this VVP is a wider discussion on either diarrheagenic NTS disease (dNTS) also associated with Salmonella Enteritidis and Salmonella Typhimurium or the development of a multivalent Salmonella vaccines targeting key serovars for use globally. This VVP for vaccines to prevent iNTS disease is intended to provide a high-level, holistic assessment of the information and data that are currently available to inform the potential public health, economic, and societal value of pipeline vaccines and vaccine-like products. Future versions of this VVP will be updated to reflect ongoing activities such as vaccine development strategies and a "Full Vaccine Value Assessment" that will inform the value proposition of an iNTS disease vaccine. This VVP was developed by a working group of subject matter experts from academia, non-profit organizations, public private partnerships, and multi-lateral organizations, and in collaboration with stakeholders from the World Health Organization African Region. All contributors have extensive expertise on various elements of the iNTS disease VVP and collectively aimed to identify current research and knowledge gaps. The VVP was developed using only existing and publicly available information.
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Affiliation(s)
| | - Bieke Tack
- Department of Clinical Sciences, Institute of Tropical Medicine Antwerp, Belgium and Department of Microbiology, Immunology and Transplantation, KU Leuven, Belgium.
| | | | - Michael J Sikorski
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD, USA.
| | | | | | | | - John A Crump
- Centre for International Health, University of Otago, New Zealand.
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Kim S, Kang H, Excler JL, Kim JH, Lee JS. The Economic Burden of Non-Typhoidal Salmonella and Invasive Non-Typhoidal Salmonella Infection: A Systematic Literature Review. Vaccines (Basel) 2024; 12:758. [PMID: 39066396 PMCID: PMC11281589 DOI: 10.3390/vaccines12070758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2024] [Revised: 06/25/2024] [Accepted: 06/28/2024] [Indexed: 07/28/2024] Open
Abstract
Non-typhoidal Salmonella (NTS) infection and invasive non-typhoidal Salmonella (iNTS) infection cause a significant global health and economic burden. This systematic review aims to investigate the reported economic burden of NTS and iNTS infection, identify research gaps, and suggest future research directions. Data from PubMed and Embase databases up to April 2022 were reviewed, and articles were screened based on predefined criteria. Cost data were extracted, categorized into direct medical costs (DMCs), direct non-medical costs (DNMCs), and indirect costs (ICs), and converted into US dollars (year 2022). Data primarily originated from high-income countries (37 out of 38), with limited representation from Africa and resource-limited settings. For inpatients, DMCs were the primary cost driver for both NTS and iNTS illnesses, with estimates ranging from USD 545.9 (Taiwan, a region of China) to USD 21,179.8 (Türkiye) for NTS and from USD 1973.1 (Taiwan, a region of China) to USD 32,507.5 (United States of America) for iNTS per case. DNMCs and ICs varied widely across studies. Although study quality improved over time, methodological differences persisted. This review underscores the lack of economic data on NTS and iNTS in resource-limited settings. It also highlights the need for economic burden data in resource-limited settings and a standardized approach to generate global datasets, which is critical for informing policy decisions, especially regarding future vaccines.
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Affiliation(s)
- Sol Kim
- International Vaccine Institute, Seoul 08826, Republic of Korea; (S.K.); (H.K.); (J.-L.E.); (J.H.K.)
| | - Hyolim Kang
- International Vaccine Institute, Seoul 08826, Republic of Korea; (S.K.); (H.K.); (J.-L.E.); (J.H.K.)
| | - Jean-Louis Excler
- International Vaccine Institute, Seoul 08826, Republic of Korea; (S.K.); (H.K.); (J.-L.E.); (J.H.K.)
| | - Jerome H. Kim
- International Vaccine Institute, Seoul 08826, Republic of Korea; (S.K.); (H.K.); (J.-L.E.); (J.H.K.)
- College of Natural Sciences, Seoul National University, Seoul 08826, Republic of Korea
| | - Jung-Seok Lee
- International Vaccine Institute, Seoul 08826, Republic of Korea; (S.K.); (H.K.); (J.-L.E.); (J.H.K.)
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3
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Greening B, Whitham HK, Aldous WK, Hall N, Garvey A, Mandernach S, Kahn EB, Nonnenmacher P, Snow J, Meltzer MI, Hoffmann S. Public Health Response to Multistate Salmonella Typhimurium Outbreak Associated with Prepackaged Chicken Salad, United States, 2018. Emerg Infect Dis 2022; 28:1254-1256. [PMID: 35608817 PMCID: PMC9155865 DOI: 10.3201/eid2806.211633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Quantifying the effect of public health actions on population health is essential when justifying sustained public health investment. Using modeling, we conservatively estimated that rapid response to a multistate foodborne outbreak of Salmonella Typhimurium in the United States in 2018 potentially averted 94 reported cases and $633,181 in medical costs and productivity losses.
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Ford L, Haywood P, Kirk MD, Lancsar E, Williamson DA, Glass K. Cost of Salmonella Infections in Australia, 2015. J Food Prot 2019; 82:1607-1614. [PMID: 31436484 DOI: 10.4315/0362-028x.jfp-19-105] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Gastroenteritis caused from infections with Salmonella enterica (salmonellosis) causes significant morbidity in Australia. In addition to acute gastroenteritis, approximately 8.8% of people develop irritable bowel syndrome (IBS) and 8.5% of people develop reactive arthritis (ReA). We estimated the economic cost of salmonellosis and associated sequel illnesses in Australia in a typical year circa 2015. We estimated incidence, hospitalizations, other health care usage, absenteeism, and premature mortality for four age groups using a variety of complementary data sets. We calculated direct costs (health care) and indirect costs (lost productivity and premature mortality) by using Monte Carlo simulation to estimate 90% credible intervals (CrI) around our point estimates. We estimated that 90,833 cases, 4,312 hospitalizations, and 19 deaths occurred from salmonellosis in Australia circa 2015 at a direct cost of AUD 23.8 million (90% CrI, 19.3 to 28.9 million) and a total cost of AUD 124.4 million (90% CrI, 107.4 to 143.1 million). When IBS and ReA were included, the estimated direct cost was 35.7 million (90% CrI, 29.9 to 42.7 million) and the total cost was AUD 146.8 million (90% CrI, 127.8 to 167.9 million). Foodborne infections were responsible for AUD 88.9 million (90% CrI, 63.9 to 112.4 million) from acute salmonellosis and AUD 104.8 million (90% CrI, 75.5 to 132.3 million) when IBS and ReA were included. Targeted interventions to prevent illness could considerably reduce costs and societal impact from Salmonella infections and sequel illnesses in Australia.
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Affiliation(s)
- Laura Ford
- National Centre for Epidemiology and Population Health, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Philip Haywood
- Centre for Health Economics Research and Evaluation, University of Technology Sydney, P.O. Box 123, Broadway, New South Wales 2007, Australia
| | - Martyn D Kirk
- National Centre for Epidemiology and Population Health, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Emily Lancsar
- Department of Health Services Research and Policy, Research School of Population Health, The Australian National University, Canberra, Australian Capital Territory 2601, Australia (ORCID: https://orcid.org/0000-0002-6253-9672 [L.F.])
| | - Deborah A Williamson
- Microbiological Diagnostic Unit Public Health Laboratory, The University of Melbourne at The Peter Doherty Institute for Infection and Immunity, Parkville, Victoria 3010, Australia
| | - Kathryn Glass
- National Centre for Epidemiology and Population Health, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
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Renu S, Markazi AD, Dhakal S, Lakshmanappa YS, Gourapura SR, Shanmugasundaram R, Senapati S, Narasimhan B, Selvaraj RK, Renukaradhya GJ. Surface engineered polyanhydride-based oral Salmonella subunit nanovaccine for poultry. Int J Nanomedicine 2018; 13:8195-8215. [PMID: 30555234 PMCID: PMC6280892 DOI: 10.2147/ijn.s185588] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
PURPOSE Salmonellosis is a severe economic threat in poultry and a public health concern. Currently available vaccines are ineffective, and thus, developing effective oral Salmonella vaccine is warranted. Especially, a potent oral vaccine such as the mucoadhesive polyanhydride nanoparticle (PNP) protects the vaccine cargo and delivers to intestinal immune sites to elicit robust mucosal immunity and mitigate Salmonella colonization and shedding. MATERIALS AND METHODS We designed a Salmonella subunit vaccine using PNP containing immunogenic Salmonella outer membrane proteins (OMPs) and flagellar (F) protein-entrapped and surface F-protein-coated PNPs (OMPs-F-PNPs) using a solvent displacement method. Using high-throughput techniques, we characterized the OMPs-F-PNPs physicochemical properties and analyzed its efficacy in layer birds vaccinated orally. RESULTS The candidate vaccine was resistant in acidic microenvironment and had ideal physicochemical properties for oral delivery in terms of particle size, charge, morphology, biocompatibility, and pH stability. In vitro, in vivo, and ex vivo studies showed that F-protein surface-anchored nanoparticles were better targeted to chicken immune cells in peripheral blood and splenocytes and intestinal Peyer's patch sites. In layer chickens inoculated orally with OMPs-F-PNPs, substantially higher OMPs-specific IgG response and secretion of Th1 cytokine IFN-γ in the serum, enhanced CD8+/CD4+ cell ratio in spleen, and increased OMPs-specific lymphocyte proliferation were observed. OMPs-F-PNPs vaccination also upregulated the expression of toll-like receptor (TLR)-2 and -4, TGF-β, and IL-4 cytokines' genes in chicken cecal tonsils (lymphoid tissues). Importantly, OMPs-F-PNPs vaccine cleared Salmonella cecal colonization in 33% of vaccinated birds. CONCLUSION This pilot in vivo study demonstrated the targeted delivery of OMPs-F-PNPs to ileum mucosal immune sites of chickens and induced specific immune response to mitigate Salmonella colonization in intestines.
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Affiliation(s)
- Sankar Renu
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA,
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA,
| | - Ashley D Markazi
- Department of Animal Sciences, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA
| | - Santosh Dhakal
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA,
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA,
| | - Yashavanth S Lakshmanappa
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA,
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA,
| | - Suren R Gourapura
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA,
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA,
| | - Revathi Shanmugasundaram
- Department of Animal Sciences, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA
| | - Sujata Senapati
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA 50011, USA
| | - Balaji Narasimhan
- Department of Chemical and Biological Engineering, Iowa State University, Ames, IA 50011, USA
| | - Ramesh K Selvaraj
- Department of Poultry Science, University of Georgia, Athens, GA 30602, USA,
| | - Gourapura J Renukaradhya
- Food Animal Health Research Program, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, OH 44691, USA,
- Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA,
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Gavin C, Simons RRL, Berriman ADC, Moorhouse D, Snary EL, Smith RP, Hill AA. A cost-benefit assessment of Salmonella-control strategies in pigs reared in the United Kingdom. Prev Vet Med 2018; 160:54-62. [PMID: 30388998 DOI: 10.1016/j.prevetmed.2018.09.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 09/19/2018] [Accepted: 09/20/2018] [Indexed: 01/05/2023]
Abstract
Pork and pork products are a major source of human salmonellosis in the United Kingdom (UK). Despite a number of surveillance programmes, the prevalence of Salmonella in the UK slaughter pig population remains over 20%. Here, we present the results of a Cost-Benefit Analysis comparing five on-farm control strategies (where the cost is the cost of implementation and the benefits are the financial savings for both the human health and pig industries). The interventions considered were: wet feed, organic acids in feed, vaccination, enhanced cleaning and disinfection and movement of outdoor breeding units. The data originate from published papers and recent UK studies. The effectiveness was assessed by adapting a previous risk assessment, originally developed for the European Food Safety Authority. Using this method, none of the intervention strategies produced a net cost-benefit. Our results suggest that the cost of implementation outweighed the savings for all interventions, even if the effectiveness could be improved. Therefore, to achieve a net cost-benefit it is essential to reduce the cost of interventions. Analyses concluded that large cost reductions (up to 96%) would be required. Use of organic acids required the smallest reduction in cost (22.7%) to achieve a net cost benefit. Uncertainty analysis suggested that a small net gain might be possible, for some of the intervention measures. But this would imply that the model greatly underestimated some key parameters, which was considered unlikely. Areas of key uncertainty were identified as the under-reporting factor (i.e. the proportion of community cases of Salmonella) and the source attribution factor (i.e. the proportion of human Salmonella cases attributable to pork products).
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Affiliation(s)
- C Gavin
- Animal and Plant Health Agency, Woodham Lane, Addlestone, Surrey, KT15 3NB, United Kingdom.
| | - R R L Simons
- Animal and Plant Health Agency, Woodham Lane, Addlestone, Surrey, KT15 3NB, United Kingdom
| | - A D C Berriman
- Animal and Plant Health Agency, Woodham Lane, Addlestone, Surrey, KT15 3NB, United Kingdom
| | - D Moorhouse
- ADAS, Pendeford House, Wobaston Road, Pendeford, Wolverhampton, WV9 5AP, United Kingdom
| | - E L Snary
- Animal and Plant Health Agency, Woodham Lane, Addlestone, Surrey, KT15 3NB, United Kingdom
| | - R P Smith
- Animal and Plant Health Agency, Woodham Lane, Addlestone, Surrey, KT15 3NB, United Kingdom
| | - A A Hill
- Animal and Plant Health Agency, Woodham Lane, Addlestone, Surrey, KT15 3NB, United Kingdom
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Abstract
This review examined the likely impact of climate change upon food-borne disease in the UK using Campylobacter and Salmonella as example organisms. Campylobacter is an important food-borne disease and an increasing public health threat. There is a reasonable evidence base that the environment and weather play a role in its transmission to humans. However, uncertainty as to the precise mechanisms through which weather affects disease, make it difficult to assess the likely impact of climate change. There are strong positive associations between Salmonella cases and ambient temperature, and a clear understanding of the mechanisms behind this. However, because the incidence of Salmonella disease is declining in the UK, any climate change increases are likely to be small. For both Salmonella and Campylobacter the disease incidence is greatest in older adults and young children. There are many pathways through which climate change may affect food but only a few of these have been rigorously examined. This provides a high degree of uncertainty as to what the impacts of climate change will be. Food is highly controlled at the National and EU level. This provides the UK with resilience to climate change as well as potential to adapt to its consequences but it is unknown whether these are sufficient in the context of a changing climate.
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Affiliation(s)
- Iain R Lake
- School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK.
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8
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Tam CC, O’Brien SJ. Economic Cost of Campylobacter, Norovirus and Rotavirus Disease in the United Kingdom. PLoS One 2016; 11:e0138526. [PMID: 26828435 PMCID: PMC4735491 DOI: 10.1371/journal.pone.0138526] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 09/01/2015] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES To estimate the annual cost to patients, the health service and society of infectious intestinal disease (IID) from Campylobacter, norovirus and rotavirus. DESIGN Secondary data analysis. SETTING The United Kingdom population, 2008-9. MAIN OUTCOME MEASURES Cases and frequency of health services usage due to these three pathogens; associated healthcare costs; direct, out-of-pocket expenses; indirect costs to patients and caregivers. RESULTS The median estimated costs to patients and the health service at 2008-9 prices were: Campylobacter £50 million (95% CI: £33m-£75m), norovirus £81 million (95% CI: £63m-£106m), rotavirus £25m (95% CI: £18m-£35m). The costs per case were approximately £30 for norovirus and rotavirus, and £85 for Campylobacter. This was mostly borne by patients and caregivers through lost income or out-of-pocket expenditure. The cost of Campylobacter-related Guillain-Barré syndrome hospitalisation was £1.26 million (95% CI: £0.4m-£4.2m). CONCLUSIONS Norovirus causes greater economic burden than Campylobacter and rotavirus combined. Efforts to control IID must prioritise norovirus. For Campylobacter, estimated costs should be considered in the context of expenditure to control this pathogen in agriculture, food production and retail. Our estimates, prior to routine rotavirus immunisation in the UK, provide a baseline vaccine cost-effectiveness analyses.
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Affiliation(s)
- Clarence C Tam
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London, United Kingdom
- * E-mail:
| | - Sarah J O’Brien
- NIHR Health Protection Research Unit in Gastrointestinal Infections, University of Liverpool, Liverpool, United Kingdom
- Institute of Infection and Global Health, University of Liverpool, Liverpool, United Kingdom
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Gupta SK, Deb R, Dey S, Chellappa MM. Toll-like receptor-based adjuvants: enhancing the immune response to vaccines against infectious diseases of chicken. Expert Rev Vaccines 2014; 13:909-25. [PMID: 24855906 DOI: 10.1586/14760584.2014.920236] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Huge productivity loss due to infectious diseases in chickens is a major problem and, hence, robust development of the poultry industry requires control of poultry health. Immunization using vaccines is routine practice; however, to combat infectious diseases, conventional vaccines as well as new-generation recombinant vaccines alone, due to relatively weak immunogenicity, may not be effective enough to provide optimum immunity. With this in mind, there is a need to incorporate better and more suitable adjuvants in the vaccines to elicit the elevated immune response in the host. Over last few decades, with the increase in the knowledge of innate immune functioning, efforts have been made to enhance vaccine potency using novel adjuvants like Toll-like receptor based adjuvant systems. In this review, we will discuss the potential use of toll-like receptor ligands as an adjuvant in vaccines against the infectious diseases of chickens.
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Affiliation(s)
- Shishir Kumar Gupta
- Division of Veterinary Biotechnology, Recombinant DNA Lab, Indian Veterinary Research Institute, Izatnagar, Bareilly-243122, UP, India
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Varga C, Pearl DL, McEwen SA, Sargeant JM, Pollari F, Guerin MT. Incidence, distribution, seasonality, and demographic risk factors of Salmonella Enteritidis human infections in Ontario, Canada, 2007-2009. BMC Infect Dis 2013; 13:212. [PMID: 23663256 PMCID: PMC3655886 DOI: 10.1186/1471-2334-13-212] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 05/08/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In Canada, surveillance systems have highlighted the increasing trend of Salmonella enterica serovar Enteritidis (S. Enteritidis) human infections. Our study objectives were to evaluate the epidemiology of S. Enteritidis infections in Ontario using surveillance data from January 1, 2007 through December 31, 2009. METHODS Annual age-and-sex-adjusted incidence rates (IRs), annual and mean age-adjusted sex-specific IRs, and mean age-and-sex-adjusted IRs by public health unit (PHU), were calculated for laboratory-confirmed S. Enteritidis cases across Ontario using direct standardization. Multivariable Poisson regression with PHU as a random effect was used to estimate incidence rate ratios (IRRs) of S. Enteritidis infections among years, seasons, age groups, and sexes. RESULTS The annual age-and-sex-adjusted IR per 100,000 person-years was 4.4 [95% CI 4.0-4.7] in 2007, and 5.2 [95% CI 4.8-5.6] in both 2008 and 2009. The annual age-adjusted sex-specific IRs per 100,000 person-years ranged from 4.5 to 5.5 for females and 4.2 to 5.2 for males. The mean age-adjusted sex-specific IR was 5.1 [95% CI 4.8-5.4] for females and 4.8 [95% CI 4.5-5.1] for males. High mean age-and-sex-adjusted IRs (6.001-8.10) were identified in three western PHUs, one northern PHU, and in the City of Toronto. Regression results showed a higher IRR of S. Enteritidis infections in 2009 [IRR = 1.18, 95% CI 1.06-1.32; P = 0.003] and 2008 [IRR = 1.17, 95% CI 1.05-1.31; P = 0.005] compared to 2007. Compared to the fall season, a higher IRR of S. Enteritidis infections was observed in the spring [IRR = 1.14, 95% CI 1.01-1.29; P = 0.040]. Children 0-4 years of age (reference category), followed by children 5-9 years of age [IRR = 0.64, 95% CI 0.52-0.78; P < 0.001] had the highest IRRs. Adults ≥ 60 years of age and 40-49 years of age [IRR = 0.31, 95% CI 0.26-0.37; P < 0.001] had the lowest IRRs. CONCLUSIONS The study findings suggest that there was an increase in the incidence of S. Enteritidis infections in Ontario from 2007 to 2008-2009, and indicate seasonal, demographic, and regional differences, which warrant further public health attention.
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Affiliation(s)
- Csaba Varga
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada
- Ontario Ministry of Agriculture, Food and Rural Affairs, Guelph, ON, N1G 4Y2, Canada
| | - David L Pearl
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Scott A McEwen
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Jan M Sargeant
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada
- Centre for Public Health and Zoonoses, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada
| | - Frank Pollari
- Centre for Foodborne, Environmental and Zoonotic Infectious Diseases, Public Health Agency of Canada, Guelph, ON, N1H 8J1, Canada
| | - Michele T Guerin
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada
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Coward C, Sait L, Cogan T, Humphrey TJ, Maskell DJ. O-antigen repeat number inSalmonella entericaserovar Enteritidis is important for egg contamination, colonisation of the chicken reproductive tract and survival in egg albumen. FEMS Microbiol Lett 2013; 343:169-76. [DOI: 10.1111/1574-6968.12143] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 03/22/2013] [Accepted: 03/27/2013] [Indexed: 11/29/2022] Open
Affiliation(s)
- Chris Coward
- Department of Veterinary Medicine; University of Cambridge; Cambridge; UK
| | - Leanne Sait
- School of Veterinary Sciences; University of Bristol; Langford; Bristol; UK
| | - Tristan Cogan
- School of Veterinary Sciences; University of Bristol; Langford; Bristol; UK
| | | | - Duncan J. Maskell
- Department of Veterinary Medicine; University of Cambridge; Cambridge; UK
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12
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Hartley C, Salisbury AM, Wigley P. CpG oligonucleotides and recombinant interferon-γ in combination improve protection in chickens to Salmonella enterica serovar Enteritidis challenge as an adjuvant component, but have no effect in reducing Salmonella carriage in infected chickens. Avian Pathol 2012; 41:77-82. [PMID: 22845324 DOI: 10.1080/03079457.2011.640305] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Salmonella enterica serovar Enteritidis is the most common cause of human salmonellosis in many developed nations. It is frequently associated with both poultry meat and eggs. In the present study we have determined whether CpG oligonucleotides that stimulate the immune system via Toll like-receptors 15 and 21 in the chicken can be used as immunomodulatory agents to break carriage of S. Enteritidis in in vitro and in vivo infection models. We also investigated its use as a component in an adjuvant to stimulate cell mediated immunity with a killed vaccine preparation. Following infection of the chicken macrophage-like cell line HD11 with Salmonella enterica serovar Gallinarum, cells were stimulated with an oligonucleotide containing a CpG motif, or with a non-CpG oligonucleotide control at concentrations ranging from 0 to 80 µM. Addition of the CpG oligonucleotide greatly enhanced clearance of S. Enteritidis in dose-dependent manner, whilst the control oligonucleotide had no significant effect. In contrast, stimulation of cells infected with S. Gallinarum had no effect. The CpG or control oligonucleotide with recombinant chicken interferon-γ was administered intramuscularly into chickens experimentally colonized with S. Enteritidis, although neither preparation produced any change in intestinal colonization levels to that in untreated control birds. Finally, CpG oligonucleotides were incorporated with recombinant interferon-γ, double-stranded RNA (Poly I:C) and squalene as a Th1-stimulating combined adjuvant for synergistic activation of cellular immunity (CASAC) together with whole killed Salmonella as the antigen as an experimental vaccine. Following vaccination and challenge of chickens with S. Enteritidis, CASAC gave significant protection to intestinal colonization whereas the same antigen given with a proprietary adjuvant did not. Neither adjuvant increased protection to systemic infection. The data suggest that adjuvants incorporating CpG motifs and interferon-γ may improve protection afforded by killed-Salmonella vaccines.
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Affiliation(s)
- Catherine Hartley
- National Centre for Zoonosis Research & Department of Infection Biology, Institute for Infection & Global Health, University of Liverpool, Neston, UK
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13
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The cost-effectiveness of pentavalent rotavirus vaccination in England and Wales. Vaccine 2012; 30:6766-76. [DOI: 10.1016/j.vaccine.2012.09.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Revised: 09/04/2012] [Accepted: 09/10/2012] [Indexed: 11/23/2022]
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14
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Coward C, Sait L, Williams L, Humphrey TJ, Cogan T, Maskell DJ. Investigation into the role of five Salmonella enterica serovar Enteritidis genomic islands in colonization of the chicken reproductive tract and other organs following oral challenge. FEMS Microbiol Lett 2012; 336:73-8. [PMID: 22889182 DOI: 10.1111/j.1574-6968.2012.02652.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Revised: 08/06/2012] [Accepted: 08/07/2012] [Indexed: 01/13/2023] Open
Abstract
Salmonella enterica serovar Enteritidis is a major cause of human gastrointestinal tract disease, infection being due in large part to the consumption of contaminated eggs. Recent genome sequencing of S. enterica serovars has identified genomic islands, the presence of which differs between serovars. Using defined mutants, we have investigated the contribution that five such loci play in the colonization of the avian reproductive tract, other organs and avian macrophages. All loci appear to play a small role in infection of liver and spleen, but not in colonization of the reproductive tract or macrophages.
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Affiliation(s)
- Chris Coward
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.
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15
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Improving resolution of public health surveillance for human Salmonella enterica serovar Typhimurium infection: 3 years of prospective multiple-locus variable-number tandem-repeat analysis (MLVA). BMC Infect Dis 2012; 12:78. [PMID: 22462487 PMCID: PMC3368731 DOI: 10.1186/1471-2334-12-78] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 03/31/2012] [Indexed: 11/26/2022] Open
Abstract
Background Prospective typing of Salmonella enterica serovar Typhimurium (STM) by multiple-locus variable-number tandem-repeat analysis (MLVA) can assist in identifying clusters of STM cases that might otherwise have gone unrecognised, as well as sources of sporadic and outbreak cases. This paper describes the dynamics of human STM infection in a prospective study of STM MLVA typing for public health surveillance. Methods During a three-year period between August 2007 and September 2010 all confirmed STM isolates were fingerprinted using MLVA as part of the New South Wales (NSW) state public health surveillance program. Results A total of 4,920 STM isolates were typed and a subset of 4,377 human isolates was included in the analysis. The STM spectrum was dominated by a small number of phage types, including DT170 (44.6% of all isolates), DT135 (13.9%), DT9 (10.8%), DT44 (4.5%) and DT126 (4.5%). There was a difference in the discriminatory power of MLVA types within endemic phage types: Simpson's index of diversity ranged from 0.109 and 0.113 for DTs 9 and 135 to 0.172 and 0.269 for DTs 170 and 44, respectively. 66 distinct STM clusters were observed ranging in size from 5 to 180 cases and in duration from 4 weeks to 25 weeks. 43 clusters had novel MLVA types and 23 represented recurrences of previously recorded MLVA types. The diversity of the STM population remained relatively constant over time. The gradual increase in the number of STM cases during the study was not related to significant changes in the number of clusters or their size. 667 different MLVA types or patterns were observed. Conclusions Prospective MLVA typing of STM allows the detection of community outbreaks and demonstrates the sustained level of STM diversity that accompanies the increasing incidence of human STM infections. The monitoring of novel and persistent MLVA types offers a new benchmark for STM surveillance. A part of this study was presented at the MEEGID × (Molecular Epidemiology and Evolutionary Genetics of Infectious Diseases) Conference, 3-5 November 2010, Amsterdam, The Netherlands
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