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Knipes AK, Summers A, Sklavounos AA, Lamanna J, de Campos RPS, Narahari T, Dixon C, Fobel R, Ndjakani YD, Lubula L, Magazani A, Muyembe JJ, Lay Y, Pukuta E, Waku-Kouomou D, Hao L, Kayembe JK, Fobel C, Dahmer J, Lee A, Ho M, Valenzuela JGC, Rackus DG, Shih R, Seale B, Chang A, Paluku G, Rota PA, Wheeler AR, Scobie HM. Use of a rapid digital microfluidics-powered immunoassay for assessing measles and rubella infection and immunity in outbreak settings in the Democratic Republic of the Congo. PLoS One 2022; 17:e0278749. [PMID: 36542608 DOI: 10.1371/journal.pone.0278749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 11/22/2022] [Indexed: 12/24/2022] Open
Abstract
The Democratic Republic of the Congo (DRC) has a high measles incidence despite elimination efforts and has yet to introduce rubella vaccine. We evaluated the performance of a prototype rapid digital microfluidics powered (DMF) enzyme-linked immunoassay (ELISA) assessing measles and rubella infection, by testing for immunoglobulin M (IgM), and immunity from natural infection or vaccine, by testing immunoglobulin G (IgG), in outbreak settings. Field evaluations were conducted during September 2017, in Kinshasa province, DRC. Blood specimens were collected during an outbreak investigation of suspected measles cases and tested for measles and rubella IgM and IgG using the DMF-ELISA in the field. Simultaneously, a household serosurvey for measles and rubella IgG was conducted in a recently confirmed measles outbreak area. DMF-ELISA results were compared with reference ELISA results tested at DRC's National Public Health Laboratory and the US Centers for Disease Control and Prevention. Of 157 suspected measles cases, rubella IgM was detected in 54% while measles IgM was detected in 13%. Measles IgG-positive cases were higher among vaccinated persons (87%) than unvaccinated persons (72%). In the recent measles outbreak area, measles IgG seroprevalence was 93% overall, while rubella seroprevalence was lower for children (77%) than women (98%). Compared with reference ELISA, DMF-ELISA sensitivity and specificity were 82% and 78% for measles IgG; 88% and 89% for measles IgM; 85% and 85% for rubella IgG; and 81% and 83% for rubella IgM, respectively. Rubella infection was detected in more than half of persons meeting the suspected measles case definition during a presumed measles outbreak, suggesting substantial unrecognized rubella incidence, and highlighting the need for rubella vaccine introduction into the national schedule. The performance of the DMF-ELISA suggested that this technology can be used to develop rapid diagnostic tests for measles and rubella.
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Rackimuthu S, Hunain R, Uday U, Muzzamil M, Rehman MU, Okonji OC, Lobo CA, Essar MY, Costa ACDS, Ahmad S, Bushabu FN. COVID-19, measles, and yellow fever: The need to reinforce vaccination in the Democratic Republic of Congo. Clin Epidemiol Glob Health 2022; 13:100956. [PMID: 35013719 DOI: 10.1016/j.cegh.2021.100956] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 12/17/2021] [Accepted: 12/30/2021] [Indexed: 01/09/2023] Open
Abstract
The immunization programs have been jeopardized all over the world due to the stay-at-home constraints imposed, to mitigate the ongoing COVID-19 pandemic. This has directly or indirectly placed the global health care system in peril, resulting in an overlapping public health crisis. With this commentary, we aim to accentuate the need to reinforce vaccination in the Democratic Republic of Congo, in lieu of the intersecting COVID-19, measles, and yellow fever outbreak, besides, providing recommendations so as to help alleviate the situation.
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Zhao ZY, Niu Y, Luo L, Hu QQ, Yang TL, Chu MJ, Chen QP, Lei Z, Rui J, Song CL, Lin SN, Wang Y, Xu JW, Zhu YZ, Liu XC, Yang M, Huang JF, Liu WK, Deng B, Liu C, Li ZY, Li PH, Su YH, Zhao BH, Huang WL, Frutos R, Chen TM. The optimal vaccination strategy to control COVID-19: a modeling study in Wuhan City, China. Infect Dis Poverty 2021; 10:140. [PMID: 34963481 PMCID: PMC8712277 DOI: 10.1186/s40249-021-00922-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [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: 08/11/2021] [Accepted: 12/15/2021] [Indexed: 01/08/2023] Open
Abstract
Background Reaching optimal vaccination rates is an essential public health strategy to control the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to simulate the optimal vaccination strategy to control the disease by developing an age-specific model based on the current transmission patterns of COVID-19 in Wuhan City, China. Methods We collected two indicators of COVID-19, including illness onset data and age of confirmed case in Wuhan City, from December 2, 2019, to March 16, 2020. The reported cases were divided into four age groups: group 1, ≤ 14 years old; group 2, 15 to 44 years old; group 3, 44 to 64 years old; and group 4, ≥ 65 years old. An age-specific susceptible-exposed-symptomatic-asymptomatic-recovered/removed model was developed to estimate the transmissibility and simulate the optimal vaccination strategy. The effective reproduction number (Reff) was used to estimate the transmission interaction in different age groups. Results A total of 47 722 new cases were reported in Wuhan City from December 2, 2019, to March 16, 2020. Before the travel ban of Wuhan City, the highest transmissibility was observed among age group 2 (Reff = 4.28), followed by group 2 to 3 (Reff = 2.61), and group 2 to 4 (Reff = 1.69). China should vaccinate at least 85% of the total population to interrupt transmission. The priority for controlling transmission should be to vaccinate 5% to 8% of individuals in age group 2 per day (ultimately vaccinated 90% of age group 2), followed by 10% of age group 3 per day (ultimately vaccinated 90% age group 3). However, the optimal vaccination strategy for reducing the disease severity identified individuals ≥ 65 years old as a priority group, followed by those 45–64 years old. Conclusions Approximately 85% of the total population (nearly 1.2 billion people) should be vaccinated to build an immune barrier in China to safely consider removing border restrictions. Based on these results, we concluded that 90% of adults aged 15–64 years should first be vaccinated to prevent transmission in China. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s40249-021-00922-4.
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Affiliation(s)
- Ze-Yu Zhao
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China.,Cirad, UMR 17, Intertryp, Université de Montpellier, Montpellier, France
| | - Yan Niu
- Chinese Center for Disease Control and Prevention, Beijing, People's Republic of China
| | - Li Luo
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Qing-Qing Hu
- Division of Public Health, School of Medicine, University of Utah, Utah, USA
| | - Tian-Long Yang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Mei-Jie Chu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Qiu-Ping Chen
- Cirad, UMR 17, Intertryp, Université de Montpellier, Montpellier, France.,Medical Insurance Office, Xiang'an Hospital of Xiamen University, Xiamen, Fujian, People's Republic of China
| | - Zhao Lei
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Jia Rui
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Cheng-Long Song
- Department of Data Science, College of Natural Sciences, Colorado State University, Fort Collins, CO, USA
| | - Sheng-Nan Lin
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Yao Wang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Jing-Wen Xu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Yuan-Zhao Zhu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Xing-Chun Liu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Meng Yang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Jie-Feng Huang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Wei-Kang Liu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Bin Deng
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Chan Liu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Zhuo-Yang Li
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Pei-Hua Li
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Yan-Hua Su
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Ben-Hua Zhao
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China
| | - Wen-Long Huang
- Fujian Provincial Center for Disease Control and Prevention, 76 Jintai Road, Gulou District, Fuzhou, Fujian, People's Republic of China.
| | - Roger Frutos
- Cirad, UMR 17, Intertryp, Université de Montpellier, Montpellier, France.
| | - Tian-Mu Chen
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, 4221-117 South Xiang'an Road, Xiang'an District, Xiamen, 361102, Fujian, People's Republic of China.
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Lu X, Fu C, Wang Q, He Q, Hee J, Takesue R, Tang K. Women's Empowerment and Children's Complete Vaccination in the Democratic Republic of the Congo: A Cross-Sectional Analysis. Vaccines (Basel) 2021; 9:1117. [PMID: 34696225 DOI: 10.3390/vaccines9101117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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] [Received: 08/06/2021] [Revised: 09/26/2021] [Accepted: 09/27/2021] [Indexed: 11/16/2022] Open
Abstract
(1) Background: The empowerment of women contributes to better child health and wellness. This study aimed to examine the association between women’s empowerment and complete vaccination of children, as recommended in the National Expanded Program on Immunization (EPI) in the Democratic Republic of the Congo (DRC). (2) Methods: In this cross-sectional study, a principal component analysis (PCA) was conducted on data from the Multiple-Indicator Cluster Survey 6 (MICS-6) to determine the dimensions of women’s empowerment. Logistic regression analysis was used to assess the association between women’s empowerment and complete vaccination of children stratified by household wealth. In total, 3524 women with children aged 12–23 months were included in the study. (3) Results: Women’s empowerment was defined by three dimensions, namely intrinsic agency, enabling resources, and social independence. Children of women with high levels of empowerment had higher odds of complete vaccination, with values of 1.63 (p = 0.002) and 1.59 (p = 0.012) for intrinsic agency and enabling resources of the empowerment, respectively, compared to the children of women with low levels of empowerment; however, social independence failed to be associated with the vaccination status of children. After stratification by household wealth, the OR of complete vaccination was higher in women from middle-income households with high levels of intrinsic agency (OR: 2.35, p = 0.021) compared to women from poor households with high levels of intrinsic agency (OR: 1.92, p = 0.004). (4) Conclusions: Higher levels of women’s empowerment, especially intrinsic agency and enabling resources, were associated with complete vaccination in children in the DRC. Household wealth status influenced the associations. The empowerment of women is crucial in promoting the complete vaccination of children and providing equal access to vaccines.
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Ashbaugh HR, Cherry JD, Hoff NA, Doshi RH, Alfonso VH, Gadoth A, Mukadi P, Higgins SG, Budd R, Randall C, Mwamba GN, Okitolonda-Wemakoy E, Muyembe-Tamfum JJ, Gerber SK, Rimoin AW. Measles antibody levels among vaccinated and unvaccinated children 6-59 months of age in the Democratic Republic of the Congo, 2013-2014. Vaccine 2021; 38:2258-2265. [PMID: 32057333 PMCID: PMC7026690 DOI: 10.1016/j.vaccine.2019.09.047] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 09/02/2019] [Accepted: 09/11/2019] [Indexed: 01/13/2023]
Abstract
Background Measles is endemic in the Democratic Republic of the Congo (DRC), and 89–94% herd immunity is required to halt its transmission. Much of the World Health Organization African Region, including the DRC, has vaccination coverage below the 95% level required to eliminate measles, heightening concern of inadequate measles immunity. Methods We assessed 6706 children aged 6–59 months whose mothers were selected for interview in the 2013–2014 DRC Demographic and Health Survey. History of measles was obtained by maternal report, and classification of children who had measles was completed using maternal recall and measles immunoglobulin G serostatus obtained from a multiplex chemiluminescent automated immunoassay dried blood spot analysis. A logistic regression model was used to identify associations of covariates with measles and seroprotection, and vaccine effectiveness (VE) was calculated. Results Out of our sample, 64% of children were seroprotected. Measles vaccination was associated with protection against measles (OR: 0.15, 95% CI: 0.03, 0.81) when administered to children 12 months of age or older. Vaccination was predictive of seroprotection at all ages. VE was highest (88%) among children 12–24 months of age. Conclusion Our results demonstrated lower than expected seroprotection against measles among vaccinated children. Understanding the factors that affect host immunity to measles will aid in developing more efficient and effective immunization programs in DRC.
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Affiliation(s)
- Hayley R Ashbaugh
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, CA 90095, United States.
| | - James D Cherry
- David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, United States.
| | - Nicole A Hoff
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Reena H Doshi
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | | | - Adva Gadoth
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, CA 90095, United States
| | - Patrick Mukadi
- Kinshasa University, School of Medicine, Kinshasa, The Democratic Republic of the Congo
| | - Stephen G Higgins
- Lentigen Technology, Incorporated, Gaithersburg, MD 20878, United States
| | - Roger Budd
- DYNEX Technologies Incorporated, Chantilly, VA 20151, United States
| | | | - Guillaume Ngoie Mwamba
- Expanded Program on Immunization, Ministry of Public Health, Kinshasa, The Democratic Republic of the Congo
| | | | | | - Sue K Gerber
- Bill and Melinda Gates Foundation, Seattle, WA 98109, United States
| | - Anne W Rimoin
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, CA 90095, United States.
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Coulborn RM, Nackers F, Bachy C, Porten K, Vochten H, Ndele E, Van Herp M, Bibala-Faray E, Cohuet S, Panunzi I. Field challenges to measles elimination in the Democratic Republic of the Congo. Vaccine 2020; 38:2800-2807. [PMID: 32111528 DOI: 10.1016/j.vaccine.2020.02.029] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 02/06/2020] [Accepted: 02/07/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND During a measles epidemic, the Ministry of Public Health (MOH) of the Democratic Republic of the Congo conducted supplementary immunization activities (2016-SIA) from August 28-September 3, 2016 throughout Maniema Province. From October 29-November 4, 2016, Médecins Sans Frontières and the MOH conducted a reactive measles vaccination campaign (2016-RVC) targeting children six months to 14 years old in seven health areas with heavy ongoing transmission despite inclusion in the 2016-SIA, and a post-vaccination survey. We report the measles vaccine coverage (VC) and effectiveness (VE) of the 2016-SIA and VC of the 2016-RVC. METHODS A cross-sectional VC cluster survey stratified by semi-urban/rural health area and age was conducted. A retrospective cohort analysis of measles reported by the parent/guardian allowed calculation of the cumulative measles incidence according to vaccination status after the 2016-SIA for an estimation of crude and adjusted VE. RESULTS In November 2016, 1145 children (6-59 months old) in the semi-urban and 1158 in the rural areas were surveyed. Post-2016-SIA VC (documentation/declaration) was 81.6% (95%CI: 76.5-85.7) in the semi-urban and 91.0% (95%CI: 84.9-94.7) in the rural areas. The reported measles incidence in October among children less than 5 years old was 5.0% for 2016-SIA-vaccinated and 11.2% for 2016-SIA-non-vaccinated in the semi-urban area, and 0.7% for 2016-SIA-vaccinated and 4.0% for 2016-SIA-non-vaccinated in the rural area. Post-2016-SIA VE (adjusted for age, sex) was 53.9% (95%CI: 2.9-78.8) in the semi-urban and 78.7% (95%CI: 0-97.1) in the rural areas. Post 2016-RVC VC (documentation/declaration) was 99.1% (95%CI: 98.2-99.6) in the semi-urban and 98.8% (95%CI: 96.5-99.6) in the rural areas. CONCLUSIONS Although our VE estimates could be underestimated due to misclassification of measles status, the VC and VE point estimates of the 2016-SIA in the semi-urban area appear suboptimal, and in combination, could not limit the epidemic. Further research is needed on vaccination strategies adapted to urban contexts.
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Affiliation(s)
| | | | - C Bachy
- Médecins Sans Frontières, Brussels, Belgium
| | | | - H Vochten
- Médecins Sans Frontières, Kinshasa, Democratic Republic of the Congo
| | - E Ndele
- Médecins Sans Frontières, Kinshasa, Democratic Republic of the Congo
| | - M Van Herp
- Médecins Sans Frontières, Brussels, Belgium
| | - E Bibala-Faray
- Ministry of Public Health, Maniema, Democratic Republic of the Congo
| | | | - I Panunzi
- Médecins Sans Frontières, Brussels, Belgium
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Chua H, Feng S, Lewnard JA, Sullivan SG, Blyth CC, Lipsitch M, Cowling BJ. The Use of Test-negative Controls to Monitor Vaccine Effectiveness: A Systematic Review of Methodology. Epidemiology 2020; 31:43-64. [PMID: 31609860 PMCID: PMC6888869 DOI: 10.1097/ede.0000000000001116] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND The test-negative design is an increasingly popular approach for estimating vaccine effectiveness (VE) due to its efficiency. This review aims to examine published test-negative design studies of VE and to explore similarities and differences in methodological choices for different diseases and vaccines. METHODS We conducted a systematic search on PubMed, Web of Science, and Medline, for studies reporting the effectiveness of any vaccines using a test-negative design. We screened titles and abstracts and reviewed full texts to identify relevant articles. We created a standardized form for each included article to extract information on the pathogen of interest, vaccine(s) being evaluated, study setting, clinical case definition, choices of cases and controls, and statistical approaches used to estimate VE. RESULTS We identified a total of 348 articles, including studies on VE against influenza virus (n = 253), rotavirus (n = 48), pneumococcus (n = 24), and nine other pathogens. Clinical case definitions used to enroll patients were similar by pathogens of interest but the sets of symptoms that defined them varied substantially. Controls could be those testing negative for the pathogen of interest, those testing positive for nonvaccine type of the pathogen of interest, or a subset of those testing positive for alternative pathogens. Most studies controlled for age, calendar time, and comorbidities. CONCLUSIONS Our review highlights similarities and differences in the application of the test-negative design that deserve further examination. If vaccination reduces disease severity in breakthrough infections, particular care must be taken in interpreting vaccine effectiveness estimates from test-negative design studies.
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Affiliation(s)
- Huiying Chua
- From the World Health Organization Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Shuo Feng
- From the World Health Organization Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Joseph A Lewnard
- Division of Epidemiology, School of Public Health, University of California, Berkeley, Berkeley, CA
| | - Sheena G Sullivan
- WHO Collaborating Centre for Reference and Research on Influenza, Royal Melbourne Hospital, and Doherty Department, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, CA
- Centre for Epidemiology and Biostatistics, School of Population and Global Health, University of Melbourne, Melbourne, Victoria, Australia
| | - Christopher C Blyth
- Division of Paediatrics, School of Medicine, Faculty of Health and Medical Sciences, The University of Western Australia, Perth, Western Australia, Australia
- Wesfarmers Centre of Vaccines and Infectious Diseases, Telethon Kids Institute, Perth, Western Australia, Australia
- Department of Infectious Diseases, Perth Children's Hospital, Perth, Western Australia, Australia
| | - Marc Lipsitch
- Department of Epidemiology, Harvard T. H. Chan School of Public Health, Boston, MA
- Center for Communicable Disease Dynamics, Harvard T. H. Chan School of Public Health, Boston, MA
| | - Benjamin J Cowling
- From the World Health Organization Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, The University of Hong Kong, Hong Kong Special Administrative Region, China
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Bogler L, Jantos N, Bärnighausen T, Vollmer S. Estimating the effect of measles vaccination on child growth using 191 DHS from 65 low- and middle-income countries. Vaccine 2019; 37:5073-5088. [PMID: 31300290 DOI: 10.1016/j.vaccine.2019.06.054] [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] [Received: 05/02/2018] [Revised: 05/06/2019] [Accepted: 06/18/2019] [Indexed: 01/22/2023]
Abstract
BACKGROUND Childhood vaccinations reduce morbidity and mortality and are highly cost-effective. They may also protect children from malnutrition and lead to improved child growth. Stunting, wasting and underweight are targets used to monitor progress towards the achievement of the sustainable development goals (SDGs). METHODS We use data from Demographic and Health Surveys (DHS) covering the period from 1990 to 2017 to estimate the effect of measles vaccination at 12 months of age on stunting, wasting, and underweight. For causal estimation, we use household- and mother-fixed effects, which allows us to compare outcomes across siblings while controlling for all observed and unobserved confounders that are shared by the siblings, such as household social characteristics and home location. In addition, we control for a wide range of sibling-varying confounders, including sex, age, birth order and mother's age at birth, as well as vaccination with diphtheria-tetanus-polio (DPT), as a broad indicator of general likelihood to receive vaccinations. RESULTS Our samples include 347,808 individuals in 132 surveys from 59 countries (for stunting), 430,963 individuals in 190 surveys from 65 countries (for wasting), and 353,520 individuals in 130 surveys from 59 countries (for underweight). Measles vaccination is associated with significantly reduced odds of stunting (odds ratio 0.90 [95% CI 0.86-0.94], p < 0.001) and underweight (odds ratio 0.90 [95% CI 0.86-0.95], p < 0.001). The association with wasting is weaker and not statistically significant (odds ratio 0.95 [95% CI 0.89-1.02], p = 0.143). Our results remain robust across several alternative specifications of our regression models. CONCLUSIONS Measles vaccination substantially reduces stunting and underweight among children in low- and middle-income countries. Increasing measles coverage from the current low to near-universal levels would provide a large boost to child growth and the attainment of the SDGs.
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Labib JR, Elsebaie EH, Abd El Fatah SA, Shalaby SF, El Khateeb E. Assessment of Routine Measles Vaccine Effectiveness Among Children Referring to Tertiary Fever Hospital in Egypt. Arch Pediatr Infect Dis 2019; 7. [DOI: 10.5812/pedinfect.90407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Ashbaugh HR, Cherry JD, Hoff NA, Doshi RH, Alfonso VH, Gadoth A, Mukadi P, Higgins SG, Budd R, Randall C, Okitolonda-Wemakoy E, Muyembe-Tamfum JJ, Gerber SK, Rimoin AW. Association of Previous Measles Infection With Markers of Acute Infectious Disease Among 9- to 59-Month-Old Children in the Democratic Republic of the Congo. J Pediatric Infect Dis Soc 2018; 8:531-538. [PMID: 30346573 PMCID: PMC6933309 DOI: 10.1093/jpids/piy099] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 10/10/2018] [Indexed: 12/19/2022]
Abstract
BACKGROUND Transient immunosuppression and increased susceptibility to other infections after measles infection is well known, but recent studies have suggested the occurrence of an "immune amnesia" that could have long-term immunosuppressive effects. METHODS We examined the association between past measles infection and acute episodes of fever, cough, and diarrhea among 2350 children aged 9 to 59 months whose mothers were selected for interview in the 2013-2014 Democratic Republic of the Congo (DRC) Demographic and Health Survey (DHS). Classification of children who had had measles was completed using maternal recall and measles immunoglobulin G serostatus obtained via dried-blood-spot analysis with a multiplex immunoassay. The association with time since measles infection and fever, cough, and diarrhea outcomes was also examined. RESULTS The odds of fever in the previous 2 weeks were 1.80 (95% confidence interval [CI], 1.25-2.60) among children for whom measles was reported compared to children with no history of measles. Measles vaccination demonstrated a protective association against selected clinical markers of acute infectious diseases. CONCLUSION Our results suggest that measles might have a long-term effect on selected clinical markers of acute infectious diseases among children aged 9 to 59 months in the DRC. These findings support the immune-amnesia hypothesis suggested by others and underscore the need for continued evaluation and improvement of the DRC's measles vaccination program.
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Affiliation(s)
- Hayley R Ashbaugh
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles,Correspondence: H. R. Ashbaugh, DVM, PhD, UCLA Fielding School of Public Health, Department of Epidemiology, Box 951772, 650 Charles Young Dr., South, Los Angeles, CA 90095 ()
| | - James D Cherry
- David Geffen School of Medicine, University of California, Los Angeles
| | - Nicole A Hoff
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles
| | - Reena H Doshi
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles
| | - Vivian H Alfonso
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles
| | - Adva Gadoth
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles
| | - Patrick Mukadi
- School of Medicine, Kinshasa University, Democratic Republic of the Congo
| | | | - Roger Budd
- Dynex Technologies Incorporated, Chantilly, Virginia
| | | | | | | | - Sue K Gerber
- Bill and Melinda Gates Foundation, Seattle, Washington
| | - Anne W Rimoin
- Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles
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Gignoux E, Polonsky J, Ciglenecki I, Bichet M, Coldiron M, Thuambe Lwiyo E, Akonda I, Serafini M, Porten K. Risk factors for measles mortality and the importance of decentralized case management during an unusually large measles epidemic in eastern Democratic Republic of Congo in 2013. PLoS One 2018. [PMID: 29538437 PMCID: PMC5851624 DOI: 10.1371/journal.pone.0194276] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [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] [Indexed: 11/24/2022] Open
Abstract
In 2013, a large measles epidemic occurred in the Aketi Health Zone of the Democratic Republic of Congo. We conducted a two-stage, retrospective cluster survey to estimate the attack rate, the case fatality rate, and the measles-specific mortality rate during the epidemic. 1424 households containing 7880 individuals were included. The estimated attack rate was 14.0%, (35.0% among children aged <5 years). The estimated case fatality rate was 4.2% (6.1% among children aged <5 years). Spatial analysis and linear regression showed that younger children, those who did not receive care, and those living farther away from Aketi Hospital early in the epidemic had a higher risk of measles related death. Vaccination coverage prior to the outbreak was low (76%), and a delayed reactive vaccination campaign contributed to the high attack rate. We provide evidences suggesting that a comprehensive case management approach reduced measles fatality during this epidemic in rural, inaccessible resource-poor setting.
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Affiliation(s)
| | | | | | - Mathieu Bichet
- Médecins Sans Frontières, Geneva, Switzerland
- Médecins Sans Frontières, Paris, France
| | | | | | - Innocent Akonda
- Ministère de la Santé Publique, Kinshassa, République Démocratique du Congo
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12
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Lipsitch M, Jha A, Simonsen L. Observational studies and the difficult quest for causality: lessons from vaccine effectiveness and impact studies. Int J Epidemiol 2018; 45:2060-2074. [PMID: 27453361 DOI: 10.1093/ije/dyw124] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/22/2016] [Indexed: 11/13/2022] Open
Abstract
Although randomized placebo-controlled trials (RCT) are critical to establish efficacy of vaccines at the time of licensure, important remaining questions about vaccine effectiveness (VE)-used here to include individual-level measures and population-wide impact of vaccine programmes-can only be answered once the vaccine is in use, from observational studies. However, such studies are inherently at risk for bias. Using a causal framework and illustrating with examples, we review newer approaches to detecting and avoiding confounding and selection bias in three major classes of observational study design: cohort, case-control and ecological studies. Studies of influenza VE, especially in seniors, are an excellent demonstration of the challenges of detecting and reducing such bias, and so we use influenza VE as a running example. We take a fresh look at the time-trend studies often dismissed as 'ecological'. Such designs are the only observational study design that can measure the overall effect of a vaccination programme [indirect (herd) as well as direct effects], and are in fact already an important part of the evidence base for several vaccines currently in use. Despite the great strides towards more robust observational study designs, challenges lie ahead for evaluating best practices for achieving robust unbiased results from observational studies. This is critical for evaluation of national and global vaccine programme effectiveness.
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Affiliation(s)
- Marc Lipsitch
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Ayan Jha
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.,Health Education & Research Institute, Charleston Area Medical Center, Charleston, WV, USA
| | - Lone Simonsen
- Department of Global Health, George Washington University, Washington, DC, USA.,Department of Public Health, University of Copenhagen, Copenhagen, Denmark
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13
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Alfonso VH, Doshi RH, Mukadi P, Higgins SG, Hoff NA, Bwaka A, Mwamba GN, Okitolonda E, Muyembe JJ, Gerber S, Rimoin AW. Prevalence of Rubella Antibodies Among Children in the Democratic Republic of the Congo. Pediatr Infect Dis J 2018; 37:28-34. [PMID: 28746265 DOI: 10.1097/INF.0000000000001703] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND While generally mild in children, rubella infection in early pregnancy can lead to miscarriage, fetal death or congenital rubella syndrome. Rubella vaccination is not yet available as a part of routine immunization in the Democratic Republic of the Congo (DRC), and the burden of infection is unknown. METHODS In collaboration with the 2013-2014 DRC Demographic and Health Survey, a serosurvey was carried out to assess population immunity to vaccine-preventable diseases. Dry blood spot samples collected from children 6-59 months of age were processed using the Dynex Technologies Multiplier FLEX chemiluminescent immunoassay platform (Dynex Technologies, Chantilly, VA). RESULTS Among the 7195 6- to 59-month-old children, 33% were positive and <1% indeterminate for rubella antibodies in weighted analyses. Seroprevalence was positively associated with age of the child and province, with seropositivity highest in Bandundu (53%) and lowest in Kasai-Oriental (20%). In multivariate analyses, serologic evidence of infection was associated with age of the mother and child, socioeconomic status and geographic location. CONCLUSIONS Rubella infection is prevalent among children in the DRC, and while most seroconversion occurs in young children, a significant proportion of children remain at risk and may enter reproductive age susceptible to rubella infection. While not currently in place, implementation of a surveillance program will provide improved estimates of both rubella virus circulation and the burden of congenital rubella syndrome. Such information will play an important role in future policy decisions, vaccine delivery strategies and may provide a basis upon which the effectiveness of rubella antigen introduction may be assessed.
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14
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Doshi RH, Shidi C, Mulumba A, Eckhoff P, Nguyen C, Hoff NA, Gerber S, Okitolonda E, Ilunga BK, Rimoin AW. The effect of immunization on measles incidence in the Democratic Republic of Congo: Results from a model of surveillance data. Vaccine 2015; 33:6786-92. [PMID: 26476363 DOI: 10.1016/j.vaccine.2015.10.020] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 10/01/2015] [Accepted: 10/06/2015] [Indexed: 11/22/2022]
Abstract
BACKGROUND Measles continues to be a leading cause of vaccine-preventable disease mortality among children under five despite a safe and efficacious vaccine being readily available. While global vaccination coverage has improved tremendously, measles outbreaks persist throughout sub-Saharan Africa. Since 2010, the Democratic Republic of Congo (DRC) has seen a resurgence of measles outbreaks affecting all 11 provinces. These outbreaks are mainly attributed to gaps in routine immunization (RI) coverage compounded with missed supplementary immunization activities (SIAs). We utilized national passive surveillance data from DRC's Integrated Disease Surveillance and Response (IDSR) system to estimate the effect of immunization on measles incidence in DRC. METHODS We investigated the decline in measles incidence post-immunization with one dose of measles containing vaccine (MCV1) with and without the addition of supplementary immunization activities (SIAs) and outbreak response immunization (ORI) campaigns. Measles case counts by health zone were obtained from the IDSR system between January 1, 2010 and December 31, 2013. The impact of measles immunization was modeled using a random effects multi-level model for count data with RI coverage levels and mass campaign activities from one year prior. RESULTS The presence of an SIA (aIRR [95% CI] 0.86 [0.60-1.25]) and ORI (0.28 [0.20-0.39]) in the year prior were both associated with a decrease in measles incidence. When interaction terms were included, our results suggested that the high levels of MCV1 reported in the year prior and the presence of either mass campaign was associated with a decrease in measles incidence. CONCLUSIONS Our results highlight the importance of a two-dose measles vaccine schedule and the need for a strong routine immunization program coupled with frequent SIAs. Repeated occurrences of large-scale outbreaks in DRC suggest that vaccination coverage rates are grossly overestimated and signify the importance of the evaluation and modification of measles prevention and control strategies.
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