ABSTRACT
Objective: Systematize the experience and identify challenges and lessons learned in the implementation of an initiative for integrated serosurveillance of communicable diseases using a multiplex bead assay in countries of the Americas. Methods: Documents produced in the initiative were compiled and reviewed. These included concept notes, internal working papers, regional meetings reports, and survey protocols from the three participating countries (Mexico, Paraguay, and Brazil) and two additional countries (Guyana and Guatemala) where serology for several communicable diseases was included in neglected tropical diseases surveys. Information was extracted and summarized to describe the experience and the most relevant challenges and lessons learned. Results: Implementing integrated serosurveys requires interprogrammatic and interdisciplinary work teams for the design of survey protocols to respond to key programmatic questions aligned to the needs of the countries. Valid laboratory results are critical and rely on the standardized installment and roll-out of laboratory techniques. Field teams require adequate training and supervision to properly implement survey procedures. The analysis and interpretation of serosurveys results should be antigen-specific, contextualizing the responses for each disease, and triangulated with programmatic and epidemiological data for making decisions tailored to specific population socioeconomic and ecologic contexts. Conclusions: Integrated serosurveillance as a complementary tool for functional epidemiological surveillance systems is feasible to use and key components should be considered: political engagement, technical engagement, and integrated planning. Aspects such as designing the protocol, selecting target populations and diseases, laboratory capacities, anticipating the capacities to analyze and interpret complex data, and how to use it are key.
ABSTRACT
BACKGROUND: During August 2017-January 2018, more than 700,000 forcibly displaced Rohingyas crossed into Cox's Bazar, Bangladesh. In response to measles and diphtheria cases, first documented in September and November 2017, respectively, vaccination campaigns targeting children <15 years old were mobilized during September 2017-March 2018. However, in a rapidly evolving emergency situation, poor sanitation, malnutrition, overcrowding, and lack of access to safe water and healthcare can increase susceptibility to infectious diseases, particularly among children. We aimed to estimate population immunity to vaccine-preventable diseases (VPDs) after vaccination activities in the camps to identify any remaining immunity gaps among Rohingya children. METHODS AND FINDINGS: We conducted a cross-sectional serologic and vaccination coverage survey in Nayapara Registered Refugee Camp ("Nayapara") and makeshift settlements (MSs) April 28, 2018 to May 31, 2018, among 930 children aged 6 months to 14 years. MSs are informal, self-settled areas with a population of more than 850,000, the majority of whom arrived after August 2017, whereas Nayapara is a registered camp and has better infrastructure than MSs, including provision of routine immunization services. Households were identified using simple random sampling (SRS) in Nayapara and multistage cluster sampling in MSs (because household lists were unavailable). Dried blood spots (DBSs) were collected to estimate seroprotection against measles, rubella, diphtheria, and tetanus, using Luminex multiplex bead assay (MBA). Caregiver interviews assessed vaccination campaign participation using vaccination card or recall. In Nayapara, 273 children aged 1 to 6 years participated; 46% were female and 88% were registered refugees. In MSs, 358 children aged 1 to 6 years and 299 children aged 7 to 14 years participated; 48% of all children in MSs were female, and none were registered refugees. In Nayapara, estimated seroprotection among 1- to 6-year-olds was high for measles, rubella, diphtheria, and tetanus (91%-98%; 95% confidence interval [CI] 87%-99%); children >6 years were not assessed. In MSs, measles seroprotection was similarly high among 1- to 6-year-olds and 7- to 14-year-olds (91% [95% CI 86%-94%] and 99% [95% CI 96%-100%], respectively, p < 0.001). Rubella and diphtheria seroprotection in MSs were significantly lower among 1- to 6-year-olds (84% [95% CI 79%-88%] and 63% [95% CI 56%-70%]) compared to 7- to 14-year-olds (96% [95% CI 90%-98%] and 77% [95% CI 69%-84%]) (p < 0.001). Tetanus seroprevalence was similar among 1- to 6-year-olds and 7- to 14-year-olds (76% [95% CI 69%-81%] and 84% [95% CI 77%-89%], respectively; p = 0.07). Vaccination campaign coverage was consistent with seroprotection in both camps. However, nonresponse, the main limitation of the study, may have biased the seroprotection and campaign coverage results. CONCLUSIONS: In this study, we observed that despite multiple vaccination campaigns, immunity gaps exist among children in MSs, particularly for diphtheria, which requires serial vaccinations to achieve maximum protection. Therefore, an additional tetanus-diphtheria campaign may be warranted in MSs to address these remaining immunity gaps. Rapid scale-up and strengthening of routine immunization services to reach children and to deliver missed doses to older children is also critically needed to close immunity gaps and prevent future outbreaks.
Subject(s)
Refugees/statistics & numerical data , Vaccination/statistics & numerical data , Vaccine-Preventable Diseases/epidemiology , Vaccine-Preventable Diseases/therapy , Adolescent , Bangladesh/epidemiology , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Infant , Male , Myanmar/ethnology , Prevalence , Seroepidemiologic Studies , Vaccine-Preventable Diseases/etiologyABSTRACT
WHO has targeted yaws for global eradication by 2020. The program goals are to interrupt the transmission in countries where yaws is endemic and to certify countries as yaws free where yaws was endemic in the past. No new rapid plasmin reagin (RPR) seroreactivity in young children is required for certification of elimination at a country level. We sought to evaluate whether antibody responses to specific treponemal antigens measured in a high-throughput multiplex bead array (MBA) assay differentiate past versus current infection and whether a nontreponemal lipoidal antigen test can be incorporated into the MBA. Serum and dried blood spot specimens collected for yaws surveillance projects in Ghana, Vanuatu, and Papua New Guinea (PNG) were run on MBA to measure antibodies against recombinant p17 (rp17) and treponemal membrane protein A (TmpA) treponemal antigens. Results were compared to standard treponemal laboratory (TPPA or TPHA [TPP(H)A]) and quantitative RPR test data. Of 589 specimens, 241 were TPP(H)A(+)/RPR(+), 88 were TPP(H)A(+)/RPR(-), 6 were TPP(H)A(-)/RPR(+), and 254 were negative for both tests. Compared to TPP(H)A, reactive concordance of rp17 was 93.7%, while reactive concordance of TmpA was only 81.9%. TmpA-specific reactivity showed good correlation with RPR titers (R(2) = 0.41; P < 0.0001). IgG responses to the lipoidal antigen used in RPR testing (cardiolipin) were not detected in the MBA. Our results suggest that TmpA can be used as a treponemal antigen marker for recent or active infection and potentially replace RPR in a high-throughput multiplex tool for large-scale yaws surveillance.
Subject(s)
Antibodies, Bacterial/blood , Epidemiological Monitoring , Serologic Tests/methods , Yaws/diagnosis , Yaws/epidemiology , Adolescent , Child , Child, Preschool , Female , Ghana , High-Throughput Screening Assays/methods , Humans , Infant , Male , Papua New Guinea , VanuatuABSTRACT
Trypanosoma cruzi, the causative agent of human Chagas disease, is endemic to the southern region of the United States where it routinely infects many host species. The indoor/outdoor housing configuration used in many non-human primate research and breeding facilities in the southern of the USA provides the opportunity for infection by T. cruzi and thus provides source material for in-depth investigation of host and parasite dynamics in a natural host species under highly controlled and restricted conditions. For cynomolgus macaques housed at such a facility, we used a combination of serial blood quantitative PCR (qPCR) and hemoculture to confirm infection in >92% of seropositive animals, although each method alone failed to detect infection in >20% of cases. Parasite isolates obtained from 43 of the 64 seropositive macaques were of 2 broad genetic types (discrete typing units, (DTU's) I and IV); both within and between these DTU groupings, isolates displayed a wide variation in growth characteristics and virulence, elicited host immune responses, and susceptibility to drug treatment in a mouse model. Likewise, the macaques displayed a diversity in T cell and antibody response profiles that rarely correlated with parasite DTU type, minimum length of infection, or age of the primate. This study reveals the complexity of infection dynamics, parasite phenotypes, and immune response patterns that can occur in a primate group, despite being housed in a uniform environment at a single location, and the limited time period over which the T. cruzi infections were established.
Subject(s)
Chagas Disease/epidemiology , Macaca fascicularis/parasitology , Monkey Diseases/parasitology , Trypanosoma cruzi/immunology , Trypanosoma cruzi/isolation & purification , Animals , Antibodies, Protozoan/blood , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Chagas Disease/immunology , Disease Models, Animal , Female , Genetic Variation/genetics , Humans , Male , Mice , Polymerase Chain Reaction , Texas/epidemiology , Trypanosoma cruzi/geneticsABSTRACT
Successful achievement of global targets for elimination of trachoma as a public health problem and eradication of yaws will require control efforts to reach marginalized populations, including refugees. Testing for serologic evidence of transmission of trachoma and yaws in residents of registered camps and a Makeshift Settlement in Cox's Bazar District, Bangladesh, was added to a serosurvey for vaccine-preventable diseases (VPDs) conducted April-May 2018. The survey was primarily designed to estimate remaining immunity gaps for VPDs, including diphtheria, measles, rubella, and polio. Blood specimens from 1- to 14-year-olds from selected households were collected and tested for antibody responses against antigens from Treponema pallidum and Chlamydia trachomatis using a multiplex bead assay to evaluate for serologic evidence of the neglected tropical diseases (NTDs) yaws and trachoma, respectively. The prevalence of antibodies against two C. trachomatis antigens in children ranged from 1.4% to 1.5% for Pgp3 and 2.8% to 7.0% for CT694. The prevalence of antibody responses against both of two treponemal antigens (recombinant protein17 and treponemal membrane protein A) tested was 0% to 0.15% in two camps. The data are suggestive of very low or no transmission of trachoma and yaws, currently or previously, in children resident in these communities. This study illustrates how integrated serologic testing can provide needed data to help NTD programs prioritize limited resources.
Subject(s)
Antibodies, Bacterial/blood , Refugees/statistics & numerical data , Serologic Tests/statistics & numerical data , Trachoma/epidemiology , Trachoma/immunology , Yaws/epidemiology , Yaws/immunology , Adolescent , Bangladesh/epidemiology , Child , Child, Preschool , Chlamydia trachomatis/immunology , Female , Humans , Infant , Male , Prevalence , Public Health , Seroepidemiologic Studies , Trachoma/blood , Treponema pallidum/immunology , Yaws/bloodABSTRACT
Little is known about enteropathogen seroepidemiology among children in low-resource settings. We measured serological IgG responses to eight enteropathogens (Giardia intestinalis, Cryptosporidium parvum, Entamoeba histolytica, Salmonella enterica, enterotoxigenic Escherichia coli, Vibrio cholerae, Campylobacter jejuni, norovirus) in cohorts from Haiti, Kenya, and Tanzania. We studied antibody dynamics and force of infection across pathogens and cohorts. Enteropathogens shared common seroepidemiologic features that enabled between-pathogen comparisons of transmission. Overall, exposure was intense: for most pathogens the window of primary infection was <3 years old; for highest transmission pathogens primary infection occurred within the first year. Longitudinal profiles demonstrated significant IgG boosting and waning above seropositivity cutoffs, underscoring the value of longitudinal designs to estimate force of infection. Seroprevalence and force of infection were rank-preserving across pathogens, illustrating the measures provide similar information about transmission heterogeneity. Our findings suggest antibody response can be used to measure population-level transmission of diverse enteropathogens in serologic surveillance.
Subject(s)
Antibodies, Bacterial/blood , Antibodies, Protozoan/blood , Antibodies, Viral/blood , Bacterial Infections/epidemiology , Caliciviridae Infections/epidemiology , Immunoglobulin G/blood , Intestinal Diseases, Parasitic/epidemiology , Age Factors , Child , Developing Countries , Disease Transmission, Infectious , Epidemiological Monitoring , Haiti/epidemiology , Humans , Kenya/epidemiology , Longitudinal Studies , Seroepidemiologic Studies , Tanzania/epidemiologyABSTRACT
[ABSTRACT]. Objective. Systematize the experience and identify challenges and lessons learned in the implementation of an initiative for integrated serosurveillance of communicable diseases using a multiplex bead assay in coun- tries of the Americas. Methods. Documents produced in the initiative were compiled and reviewed. These included concept notes, internal working papers, regional meetings reports, and survey protocols from the three participating countries (Mexico, Paraguay, and Brazil) and two additional countries (Guyana and Guatemala) where serology for sev- eral communicable diseases was included in neglected tropical diseases surveys. Information was extracted and summarized to describe the experience and the most relevant challenges and lessons learned. Results. Implementing integrated serosurveys requires interprogrammatic and interdisciplinary work teams for the design of survey protocols to respond to key programmatic questions aligned to the needs of the countries. Valid laboratory results are critical and rely on the standardized installment and roll-out of laboratory tech- niques. Field teams require adequate training and supervision to properly implement survey procedures. The analysis and interpretation of serosurveys results should be antigen-specific, contextualizing the responses for each disease, and triangulated with programmatic and epidemiological data for making decisions tailored to specific population socioeconomic and ecologic contexts. Conclusions. Integrated serosurveillance as a complementary tool for functional epidemiological surveil- lance systems is feasible to use and key components should be considered: political engagement, technical engagement, and integrated planning. Aspects such as designing the protocol, selecting target populations and diseases, laboratory capacities, anticipating the capacities to analyze and interpret complex data, and how to use it are key.
[RESUMEN]. Objetivo. Sistematizar la experiencia y determinar los desafíos y las enseñanzas obtenidas durante la apli- cación de una iniciativa de serovigilancia integrada de enfermedades transmisibles mediante un ensayo de perlas múltiples en países de la Región de las Américas. Métodos. Se recopilaron y revisaron los documentos generados en el marco de la iniciativa. Estos incluían notas conceptuales, documentos de trabajo internos, informes de reuniones regionales y protocolos de encuesta de los tres países participantes (Brasil, México y Paraguay) y otros dos países (Guatemala y Guyana) donde en las encuestas sobre enfermedades tropicales desatendidas también se incluía la serología para varias enfermedades transmisibles. Se recabó y resumió la información para describir tanto la experiencia como los desafíos y las enseñanzas de mayor relevancia. Resultados. La realización de encuestas serológicas integradas requiere equipos de trabajo interprogramáti- cos e interdisciplinarios para la elaboración de protocolos de encuesta que permitan responder a cuestiones programáticas fundamentales y ajustadas a las necesidades de los países. Es imprescindible contar con resultados de laboratorio válidos, para lo que es preciso que sus técnicas e instalaciones estén estandariza- das. Para que los equipos de campo puedan ejecutar correctamente los procedimientos de la encuesta, deben contar con una formación y supervisión adecuadas. El análisis y la interpretación de los resultados de las encuestas serológicas deben ser específicos para cada antígeno, situar las respuestas en el contexto de cada enfermedad y triangularse con los datos programáticos y epidemiológicos para tomar decisiones adaptadas a los contextos socioeconómicos y ecológicos específicos de la población. Conclusiones. Es uso de la vigilancia serológica integrada como una herramienta complementaria en los sistemas funcionales de vigilancia epidemiológica es algo posible; para esto deben tenerse en cuenta ciertos elementos fundamentales: el compromiso político, el compromiso técnico y la planificación integrada. A tal efecto, son fundamentales ciertos elementos como el diseño del protocolo, la selección de los grupos pobla- cionales y las enfermedades objetivo, la capacidad de los laboratorios, y la previsión de las capacidades de análisis e interpretación de datos complejos y la forma de utilizarlos.
[RESUMO]. Objetivo. Sistematizar a experiência e identificar desafios e lições aprendidas na implementação de uma iniciativa de vigilância sorológica integrada de doenças transmissíveis, usando ensaio de micro-esferas multiplex em países das Américas. Métodos. Os documentos produzidos na iniciativa foram compilados e examinados, e incluíram notas con- ceituais, documentos internos de trabalho, relatórios de reuniões regionais e protocolos de pesquisa dos três países participantes (México, Paraguai e Brasil) e de dois países adicionais (Guiana e Guatemala), onde a vigilância sorológica de várias doenças transmissíveis foi incluída em pesquisas sobre doenças tropicais negligenciadas. As informações foram extraídas e resumidas para descrever a experiência e os desafios e as lições aprendidas mais relevantes. Resultados. A implementação de inquéritos sorológicos integrados requer equipes de trabalho interpro- gramáticas e interdisciplinares para o delineamento de protocolos que respondam a questões programáticas chave, alinhadas com as necessidades dos países. Resultados laboratoriais válidos são essenciais, e depen- dem da instalação e implantação padronizadas de técnicas laboratoriais. As equipes de campo precisam de treinamento e supervisão apropriados para implementar adequadamente os procedimentos de pesquisa. A análise e a interpretação dos resultados dos inquéritos sorológicos devem ser antígeno-específicas, con- textualizando as respostas para cada doença, e trianguladas com dados programáticos e epidemiológicos para a tomada de decisões adaptadas aos contextos socioeconômicos e ecológicos específicos de cada população. Conclusões. A vigilância sorológica integrada como ferramenta complementar para sistemas de vigilância epidemiológica funcionais é viável. Os componentes-chave a seguir devem ser considerados: engajamento político, engajamento técnico e planejamento integrado. Aspectos como o delineamento do protocolo, a seleção de populações-alvo e doenças-alvo, a capacidade laboratorial, a previsão das capacidades para análise e interpretação de dados complexos e como usá-los são fundamentais.
Subject(s)
Serology , Health Surveillance System , Communicable Diseases , Americas , Serology , Health Surveillance , Communicable Diseases , Americas , Health Surveillance , Communicable Diseases , AmericasABSTRACT
ABSTRACT Objective. Systematize the experience and identify challenges and lessons learned in the implementation of an initiative for integrated serosurveillance of communicable diseases using a multiplex bead assay in countries of the Americas. Methods. Documents produced in the initiative were compiled and reviewed. These included concept notes, internal working papers, regional meetings reports, and survey protocols from the three participating countries (Mexico, Paraguay, and Brazil) and two additional countries (Guyana and Guatemala) where serology for several communicable diseases was included in neglected tropical diseases surveys. Information was extracted and summarized to describe the experience and the most relevant challenges and lessons learned. Results. Implementing integrated serosurveys requires interprogrammatic and interdisciplinary work teams for the design of survey protocols to respond to key programmatic questions aligned to the needs of the countries. Valid laboratory results are critical and rely on the standardized installment and roll-out of laboratory techniques. Field teams require adequate training and supervision to properly implement survey procedures. The analysis and interpretation of serosurveys results should be antigen-specific, contextualizing the responses for each disease, and triangulated with programmatic and epidemiological data for making decisions tailored to specific population socioeconomic and ecologic contexts. Conclusions. Integrated serosurveillance as a complementary tool for functional epidemiological surveillance systems is feasible to use and key components should be considered: political engagement, technical engagement, and integrated planning. Aspects such as designing the protocol, selecting target populations and diseases, laboratory capacities, anticipating the capacities to analyze and interpret complex data, and how to use it are key.
Resumen Objetivo. Sistematizar la experiencia y determinar los desafíos y las enseñanzas obtenidas durante la aplicación de una iniciativa de serovigilancia integrada de enfermedades transmisibles mediante un ensayo de perlas múltiples en países de la Región de las Américas. Métodos. Se recopilaron y revisaron los documentos generados en el marco de la iniciativa. Estos incluían notas conceptuales, documentos de trabajo internos, informes de reuniones regionales y protocolos de encuesta de los tres países participantes (Brasil, México y Paraguay) y otros dos países (Guatemala y Guyana) donde en las encuestas sobre enfermedades tropicales desatendidas también se incluía la serología para varias enfermedades transmisibles. Se recabó y resumió la información para describir tanto la experiencia como los desafíos y las enseñanzas de mayor relevancia. Resultados. La realización de encuestas serológicas integradas requiere equipos de trabajo interprogramáticos e interdisciplinarios para la elaboración de protocolos de encuesta que permitan responder a cuestiones programáticas fundamentales y ajustadas a las necesidades de los países. Es imprescindible contar con resultados de laboratorio válidos, para lo que es preciso que sus técnicas e instalaciones estén estandarizadas. Para que los equipos de campo puedan ejecutar correctamente los procedimientos de la encuesta, deben contar con una formación y supervisión adecuadas. El análisis y la interpretación de los resultados de las encuestas serológicas deben ser específicos para cada antígeno, situar las respuestas en el contexto de cada enfermedad y triangularse con los datos programáticos y epidemiológicos para tomar decisiones adaptadas a los contextos socioeconómicos y ecológicos específicos de la población. Conclusiones. Es uso de la vigilancia serológica integrada como una herramienta complementaria en los sistemas funcionales de vigilancia epidemiológica es algo posible; para esto deben tenerse en cuenta ciertos elementos fundamentales: el compromiso político, el compromiso técnico y la planificación integrada. A tal efecto, son fundamentales ciertos elementos como el diseño del protocolo, la selección de los grupos poblacionales y las enfermedades objetivo, la capacidad de los laboratorios, y la previsión de las capacidades de análisis e interpretación de datos complejos y la forma de utilizarlos.
RESUMO Objetivo. Sistematizar a experiência e identificar desafios e lições aprendidas na implementação de uma iniciativa de vigilância sorológica integrada de doenças transmissíveis, usando ensaio de micro-esferas multiplex em países das Américas. Métodos. Os documentos produzidos na iniciativa foram compilados e examinados, e incluíram notas conceituais, documentos internos de trabalho, relatórios de reuniões regionais e protocolos de pesquisa dos três países participantes (México, Paraguai e Brasil) e de dois países adicionais (Guiana e Guatemala), onde a vigilância sorológica de várias doenças transmissíveis foi incluída em pesquisas sobre doenças tropicais negligenciadas. As informações foram extraídas e resumidas para descrever a experiência e os desafios e as lições aprendidas mais relevantes. Resultados. A implementação de inquéritos sorológicos integrados requer equipes de trabalho interprogramáticas e interdisciplinares para o delineamento de protocolos que respondam a questões programáticas chave, alinhadas com as necessidades dos países. Resultados laboratoriais válidos são essenciais, e dependem da instalação e implantação padronizadas de técnicas laboratoriais. As equipes de campo precisam de treinamento e supervisão apropriados para implementar adequadamente os procedimentos de pesquisa. A análise e a interpretação dos resultados dos inquéritos sorológicos devem ser antígeno-específicas, contextualizando as respostas para cada doença, e trianguladas com dados programáticos e epidemiológicos para a tomada de decisões adaptadas aos contextos socioeconômicos e ecológicos específicos de cada população. Conclusões. A vigilância sorológica integrada como ferramenta complementar para sistemas de vigilância epidemiológica funcionais é viável. Os componentes-chave a seguir devem ser considerados: engajamento político, engajamento técnico e planejamento integrado. Aspectos como o delineamento do protocolo, a seleção de populações-alvo e doenças-alvo, a capacidade laboratorial, a previsão das capacidades para análise e interpretação de dados complexos e como usá-los são fundamentais.