Societal impact of dengue outbreaks: Stakeholder perceptions and related implications. A qualitative study in Brazil, 2015

Sustainable Dengue Prevention and Management: Integrating Dengue Vaccination Strategies with Population Perspectives

The GEMKAP study (2023) unveiled consistent knowledge, attitude, and practice (KAP) levels across Asia-Pacific (APAC) and Latin America (LATAM) countries regarding dengue, with variations in the willingness to vaccinate. Despite an overall KAP parity, the disparities within and between the countries indicated the need for both overarching and tailored strategies. Population-wide gaps in dengue awareness result in suboptimal vaccination priorities and preventive measures. This commentary delves into identifying the drivers and barriers for implementing a multi-pronged dengue prevention and management program, emphasizing the pivotal role of vaccination alongside education and vector control. Drawing on expert interviews in APAC and LATAM, informed by the Consolidated Framework for Implementation Research (CFIR), four key themes emerged: prioritizing and continuously advocating for dengue on national health agendas, fostering stakeholder collaboration, incorporating population perspectives for behavioral change, and designing sustainable dengue prevention and management programs. Successful implementation requires evidence-based decision making and a comprehensive understanding of population dynamics to design adaptive education tailored to diverse population views. This commentary provides actionable strategies for enhancing dengue prevention and management, with a pronounced emphasis on dengue vaccination, advocating for a holistic, population-centric approach for sustained effectiveness.

A Qualitative Analysis of the Perceptions of Stakeholders Involved in Vector Control and Vector-Borne Disease Research and Surveillance in Orinoquia, Colombia

Colombia has a tropical climate and environmental conditions that favour the circulation of most of the known vector-borne diseases (VBDs). Protocols have been established and implemented to address the threats of these diseases, but they are for country-wide use and do not take into consideration the nuances of the different environments of the country. Almost the entire population is vulnerable to infection with one or more VBD. This study aims to characterise the perceptions and experiences of stakeholders involved in vector control and VBDs in the Orinoquia region in Colombia. Two panel discussions, and 12 semi-structured interviews, were conducted. Experts from the Colombian National Health Institute (INS), health secretaries from Meta, Guaviare and Vichada Departments, academic researchers, and individuals from private vector control companies participated. All sessions were recorded, transcribed, and translated, and then subject to thematic analysis. Three major themes emerged: involvement, limitations, and recommendations. Results showed that participants are engaged in vector surveillance activities, education, and vector control research. Participants focused on problems of disjointed efforts towards VBD control between health secretaries and the health ministry, as well as societal issues, such as socioeconomic, cultural, and political issues, which became the rationale for the lack of vector control resources. Responses in the panel discussions and interviews overlapped in opinions, and suggested that vector control could be improved through better communication between vector control bodies, strengthened engagement with vulnerable communities, more collaborative actions, and a more balanced distribution of resources.

Acceptability of a hypothetical dengue vaccine and the potential impact of dengue vaccination on personal vector control behavior: a qualitative study in Fortaleza, Brazil

BACKGROUND

Dengue is the most rapidly spreading viral vector-borne disease in the world. Promising new dengue vaccines have contributed to a growing consensus that effective dengue control will require integrated strategies of vaccination and vector control. In this qualitative study, we explored the perspectives of residents of Fortaleza, Brazil on acceptability of a hypothetical safe and effective dengue vaccine, specific drivers of dengue vaccine acceptance or hesitance, and the expected impact of dengue vaccination on their personal vector control practices.

METHODS

A total of 43 in-depth interviews were conducted from April to June 2022 with Fortaleza residents from a diverse range of educational and professional backgrounds, with and without recent personal experiences of symptomatic dengue infections. Data were analyzed using the principles of inductive grounded theory methodology.

RESULTS

Our findings indicate that knowledge of dengue transmission, symptoms, and prevention methods was strong across respondents. Respondents described willingness to accept a hypothetical dengue vaccine for themselves and their children, while emphasizing that the vaccine must be demonstrably safe and effective. Respondents expressed diverse perspectives on how receiving a safe and effective dengue vaccine might influence their personal vector control behaviors, relating these behaviors to their perception of risk from other Aedes mosquito-carried infections and beliefs about the role of vector control in maintaining household cleanliness.

CONCLUSIONS

Our study findings provide community-level perspectives on dengue vaccination and its potential impact on personal vector control behavior for policymakers and program managers in Fortaleza to consider as new dengue vaccines become available. With the introduction of any new dengue vaccine, community perspectives and emerging concerns that may drive vaccine hesitancy should be continuously sought out. Improved urban infrastructure and efforts to engage individuals and communities in vector control may be needed to optimize the impact of future dengue vaccinations and prevent rising cases of other arboviruses such as Zika and chikungunya.

Determining Perceived Self-Efficacy for Preventing Dengue Fever in Two Climatically Diverse Mexican States: A Cross-Sectional Study

Knowledge of dengue fever and perceived self-efficacy toward dengue prevention does not necessarily translate to the uptake of mosquito control measures. Understanding how these factors (knowledge and self-efficacy) influence mosquito control measures in Mexico is limited. Our study sought to bridge this knowledge gap by assessing individual-level variables that affect the use of mosquito control measures. A cross-sectional survey with 623 participants was administered online in Mexico from April to July 2021. Multiple linear regression and multiple logistic regression models were used to explore factors that predicted mosquito control scale and odds of taking measures to control mosquitoes in the previous year, respectively. Self-efficacy (β = 0.323, p-value = < 0.0001) and knowledge about dengue reduction scale (β = 0.316, p-value =< 0.0001) were the most important predictors of mosquito control scale. The linear regression model explained 24.9% of the mosquito control scale variance. Increasing age (OR = 1.064, p-value =< 0.0001) and self-efficacy (OR = 1.020, p-value = 0.0024) were both associated with an increase in the odds of taking measures against mosquitoes in the previous year. There is a potential to increase mosquito control awareness and practices through the increase in knowledge about mosquito reduction and self-efficacy in Mexico.

Devastating dengue outbreak amidst COVID-19 pandemic in Bangladesh: an alarming situation

Dengue fever is a viral infection caused by Aedes mosquitoes that has recently expanded fast in many of the WHO member states globally. Female mosquitoes, mostly Aedes aegypti and, to a smaller degree, Aedes albopictus, disseminate dengue virus. Dengue fever has been more common in recent decades all across the world, and Bangladesh is no exception. As the COVID-19 outbreak wreaks havoc, the following rise in dengue illnesses has been a source of considerable concern. As the health care has been stretched thin in these dangerous times, the vulnerable population has been left at the mercy of these two viral infections. Lack of knowledge, major legislative changes, poor eradication initiatives, and a lack of financing resources have all contributed to the increase in numbers. Stakeholders and policymakers must begin taking meaningful actions and implementing well-thought-out adjustments immediately, or the situation will worsen, resulting in the loss of thousands of innocent lives.

Tipologías familiares para la prevención del dengue en Colombia

Se buscó analizar la relación entre las características sociodemográficas y los factores de riesgo del contexto para establecer tipologías familiares en función del control y prevención del dengue en el Departamento de Córdoba, Colombia, a través de un estudio analítico transversal realizado durante el año 2021 con 328 familias. Para el efecto se utilizó la técnica del muestreo estratificado aleatorio proporcional, con un nivel de 90% de confianza y 7% de error. La medición de las asociaciones entre pares de variables se hizo mediante la prueba chi-cuadrado a un nivel de significancia del 5%. Para la medición en conjunto de las asociaciones entre variables se utilizó un análisis de correspondencias múltiple. La agrupación de las familias se hizo mediante un análisis de conglomerados (clúster) y el método aglomerativo jerárquico de Ward. Se determinaron cuatro tipologías de familias, resaltándose dos entre ellas. El primero, de 163 hogares, principalmente de Montería, agrupa familias con mejores niveles educativos, mayores ingresos, mayor participación en programas preventivos, mejor acceso a servicios públicos y menor presencia de aguas estancadas; el segundo grupo, lo integran familias con primaria incompleta, precariedad en el acceso al servicio de agua potable y/o alcantarillado, menores ingresos económicos y mayor prevalencia de los detonantes para la propagación del vector. El análisis del vínculo familia/prevención del dengue amerita la profundización de estudios sobre el tema para la implementación de estrategias integrales contextualizadas que atiendan las particularidades del territorio y la variabilidad de las características sociodemográficas.

Surveillance and Epidemiology of Dengue in Medellín, Colombia from 2009 to 2017

Dengue is the most prevalent arthropod-borne viral disease in humans, primarily transmitted by the Aedes aegypti mosquito. We conducted a descriptive analysis of dengue cases from 2009 to 2017 in Medellín, Colombia, using data available from the Secretariat of Health. We analyzed the burden of outbreak years on the healthcare system, risk of cases exhibiting severe illness, potential disease surveillance problems, gender and age as risk factors, and spatiotemporal patterns of disease occurrence. Our data consisted of 50,083 cases, separated based on whether they were diagnostic test negative, diagnostic test positive (primarily IgM ELISA), clinically confirmed, epidemiologically linked, or probable. We used dengue incidence to analyze epidemiological trends between our study years, related to human movement patterns, between gender and age-groups, and spatiotemporally. We used risk to analyze the severity of dengue cases between the study years. We identified human movement could contributed to dengue spread, and male individuals (incidence rate: 0.86; 95% CI: 0.76-0.96) and individuals younger than 15 years (incidence rate: 1.24; 95% CI: 1.13-1.34) have higher incidence of dengue and located critical parts of the city where dengue incidence was high. Analysis was limited by participant diagnostic information, data concerning circulating strains, and a lack of phylogenetic information. Understanding the characteristics of dengue is a fundamental part of improving the health outcomes of at-risk populations. This analysis will be useful to support studies and initiatives to counteract dengue and provide context to the surveillance data collected by the health authorities in Medellín.

Molecular characterization of the viral structural protein genes in the first outbreak of dengue virus type 2 in Hunan Province, inland China in 2018

Background

An unexpected dengue outbreak occurred in Hunan Province in 2018. This was the first dengue outbreak in this area of inland China, and 172 cases were reported.

Methods

To verify the causative agent of this outbreak and characterise the viral genes, the genes encoding the structural proteins C/prM/E of viruses isolated from local residents were sequenced followed by mutation and phylogenetic analysis. Recombination, selection pressure, potential secondary structure and three-dimensional structure analyses were also performed.

Results

Phylogenetic analysis revealed that all epidemic strains were of the cosmopolitan DENV-2 genotype and were most closely related to the Zhejiang strain (MH010629, 2017) and then the Malaysia strain (KJ806803, 2013). Compared with the sequence of DENV-2SS, 151 base substitutions were found in the sequences of 89 isolates; these substitutions resulted in 20 non-synonymous mutations, of which 17 mutations existed in all samples (two in the capsid protein, six in the prM/M proteins, and nine in the envelope proteins). Moreover, amino acid substitutions at the 602nd (E322:Q → H) and 670th (E390: N → S) amino acids may have enhanced the virulence of the epidemic strains. One new DNA binding site and five new protein binding sites were observed. Two polynucleotide binding sites and seven protein binding sites were lost in the epidemic strains compared with DENV-2SS. Meanwhile, five changes were found in helical regions. Minor changes were observed in helical transmembrane and disordered regions. The 429th amino acid of the E protein switched from a histamine (positively charged) to an asparagine (neutral) in all 89 isolated strains. No recombination events or positive selection pressure sites were observed. To our knowledge, this study is the first to analyse the genetic characteristics of epidemic strains in the first dengue outbreak in Hunan Province in inland China.

Conclusions

The causative agent is likely to come from Zhejiang Province, a neighbouring province where dengue fever broke out in 2017. This study may help clarify the intrinsic geographical relatedness of DENV-2 and contribute to further research on pathogenicity and vaccine development.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-05823-3.

Guillain-Barré syndrome associated with Zika virus infection in Brazil: a cost-of-illness study

BACKGROUND

Guillain-Barré syndrome (GBS) is a serious, acute paralytic neuropathy of autoimmune aetiology, usually associated with a previous infection. The current study aims to estimate the costs of GBS associated with Zika virus (ZIKV) infection in Brazil.

METHODS

A cost-of-illness study was conducted from the perspective of the Brazilian public health system (Sistema Único de Saúde [SUS]) and Brazilian society for the year 2016. Direct and indirect costs were estimated by a mixed macrocosting and microcosting approach.

RESULTS

The total cost of ZIKV-associated GBS in Brazil was US$11 997 225.85, consisting of the costs of symptomatic ZIKV infection before onset of GBS (direct costs US$2011.51, indirect costs US$19 780.53) and the costs that followed development of GBS (direct costs US$4 722 980.89, indirect costs US$7 252 452.92). The cost of treatment with human immunoglobulin (US$3 263 210.50) and the cost of productivity losses associated with potential years of working life lost due to early mortality (US$4 398 551.72) were particularly noteworthy.

CONCLUSIONS

These findings suggest that ZIKV-associated GBS is costly to Brazil, especially due to productivity losses and hospitalization. This highlights the importance of investing in the prevention of ZIKV infection and in the care of patients with GBS.

Antiviral Activity of Benzavir-2 against Emerging Flaviviruses

Most flaviviruses are arthropod-borne viruses, transmitted by either ticks or mosquitoes, and cause morbidity and mortality worldwide. They are endemic in many countries and have recently emerged in new regions, such as the Zika virus (ZIKV) in South-and Central America, the West Nile virus (WNV) in North America, and the Yellow fever virus (YFV) in Brazil and many African countries, highlighting the need for preparedness. Currently, there are no antiviral drugs available to treat flavivirus infections. We have previously discovered a broad-spectrum antiviral compound, benzavir-2, with potent antiviral activity against both DNA- and RNA-viruses. Our purpose was to investigate the inhibitory activity of benzavir-2 against flaviviruses. We used a ZIKV ZsGreen-expressing vector, two lineages of wild-type ZIKV, and other medically important flaviviruses. Benzavir-2 inhibited ZIKV derived reporter gene expression with an EC₅₀ value of 0.8 ± 0.1 µM. Furthermore, ZIKV plaque formation, progeny virus production, and viral RNA expression were strongly inhibited. In addition, 2.5 µM of benzavir-2 reduced infection in vitro in three to five orders of magnitude for five other flaviviruses: WNV, YFV, the tick-borne encephalitis virus, Japanese encephalitis virus, and dengue virus. In conclusion, benzavir-2 was a potent inhibitor of flavivirus infection, which supported the broad-spectrum antiviral activity of benzavir-2.

Barriers to Engaging Communities in a Dengue Vector Control Program: An Implementation Research in an Urban Area in Hanoi City, Vietnam

The dengue situation in the urban setting of Hanoi city, Vietnam, is emerging, focusing on inner districts. Previous studies showed that a dengue vector control program in Hanoi was not effective because of the lack of adequate engagement of the local government authorities, health sector, and community. This implementation research aimed to explore barriers to implementing community engagement in a dengue vector control program in an urban district of Hanoi city. Ten in-depth interviews and 14 focus group discussions were conducted at Lang Thuong, Khuong Thuong, Tho Quan, and Kim Lien wards in Dong Da district, Hanoi city. Data collection was implemented from April to June 2017. All discussions were recorded and transcribed verbatim. Data were analyzed using the content analysis approach. Secondary data from the dengue vector control program reports were used to support the qualitative evidence. We found that the barriers to implementing effective community engagement were as follows: 1) lack of interest and an attitude of dependency on action from the health sector of local people's committee, 2) lack of enthusiasm of mass organizations and community leaders, 3) overburdened workloads and lack of communication skills from health sector, 4) low awareness and readiness from community, 5) lack of detailed policy guidelines and low enforcement of related policy, and 6) limited budget. Recommended actions should be made to improve the community engagement in the current resource-limited context of Vietnam by both top-down and bottom-up approaches.