Clinical and epidemiologic characteristics associated with dengue during and outside the 2016 outbreak identified in health facility-based surveillance in Ouagadougou, Burkina Faso

Estimating dengue burden among family contacts through cluster investigation around probable cases in 2022 and 2023 in the Central Region, Burkina Faso

BACKGROUND

In 2023, Burkina Faso experienced the largest dengue epidemic ever in Africa. This study aimed to estimate the prevalence of symptomatic, subclinical, and asymptomatic dengue and determine the associated factors among adult contacts of dengue in the Central Region, Burkina Faso.

METHODS

This cross-sectional study included contacts of dengue probable cases through cluster sampling in 2022-2023. These suspected cases that tested positive were identified from the five health facilities (Pissy CMA, Saaba CM, Kossodo CMA, Samandin CM, and Marcoussis CSPS) that reported the highest number of cases in 2021 per district. All participants underwent dengue and malaria rapid diagnostic tests (RDT). Samples positive for non-structural 1 protein antigen (AgNS1) and/or immunoglobulin M (IgM) were tested for serotype detection by reverse transcription polymerase chain reaction (RT-PCR). Binary logistic regression was done to identify the determinants of asymptomatic, subclinical, and symptomatic dengue among contacts of probable dengue cases.

RESULTS

A total of 484 contacts were included, mostly in 2023 (75.2%). Most participants were females (58.6%), residing (24.3%) and passing their daytime (23.1%) in Saaba. The overall prevalence of dengue was estimated at 15.1% [95% confidence interval (CI): 12.0-18.6%], representing cases not seeking care in hospitals. Asymptomatic cases represented 2.9% (95% CI: 1.6-4.8%). Subclinical and symptomatic cases accounted for 6.0% (95% CI: 4.1-8.5%) and 6.2% (95% CI: 4.2-8.7%), respectively. Of the 58 samples tested by RT-PCR, 10 were confirmed for serotype 3 in 2023. Malaria cases were estimated at 5.6% (95% CI: 3.7-8.0%). After adjustment, participants claiming that a virus transmits dengue were likelier to have asymptomatic dengue [adjusted odds ratio (aOR) = 7.1, 95% CI: 2.4-21.0]. From the multivariable analysis, subclinical dengue was statistically associated with being included in the study in 2023 (aOR = 30.2, 95% CI: 2.0-455.5) and spending the daytime at Arrondissement 4 (aOR = 11.5, 95% CI: 1.0-131.0). After adjustment, symptomatic dengue was associated with living less than 50 m away from cultivated land (aOR = 2.8, 95% CI: 1.1-6.9) and living less than 50 m from a stretch of water (aOR = 0.1, 95% CI: 0.0-0.6).

CONCLUSIONS

The overall burden of dengue among populations not seeking care in hospitals was quite high, with few asymptomatic cases. Efforts to manage dengue cases should also target non-hospital cases and raise population awareness. The 2023 epidemic could be due to dengue virus (DENV)-3.

Determinants and prevalence of symptomatic dengue fever among adults in the Central Region of Burkina Faso: a hospital-based cross-sectional study

BACKGROUND

Dengue fever (DF) is a significant public health concern in Burkina Faso, particularly in the Central Region, previously endemic for malaria. However, limited research has focused on dengue prevalence and associated factors among adult febrile patients in this region. This study aimed to estimate the prevalence of symptomatic dengue fever among adults and identify the sociodemographic and clinical determinants of the disease.

METHODS

A seroepidemiological cross-sectional study was conducted in the Central Region of Burkina Faso, through a three-stage sampling. Five health facilities, one from each of the region five districts, were purposively selected. Febrile patients aged 16 and older, suspected of having dengue, were included in the study, after consenting. Bivariate analyses and multivariate binary logistic regression were done at a 5% confidence level.

RESULTS

A total of 637 patients between the ages of 16 and 90 years were included. Most of the participants were females (58.71%). Most dengue cases resided in Arrondissement 4 (59.62%), or were present in the Arrondissement 4 at daytime during the previous days (51.92%). 52.90% of the participants knew of dengue. Dengue prevalence was estimated at 8.16% (95% CI: 6.16%-10.57%). The most frequent markers for dengue were immunoglobulins M detected in 4.40% (2.94%-6.29%), followed by Antigen NS1 at 4.24% (95% CI: 2.81%-6.11%). The Antigen NS1 marker was associated with myalgia (p = 0.024), vomiting (p < 0.001), hemorrhagic manifestations (p = 0.001), and anorexia (p < 0.001). Staying at Arrondissement 4 (vs staying at Saaba) during daytime (aOR = 2.36 95% CI: 1.03-5.45; p = 0.044) significantly increased the odds of dengue. Dengue cases were about 3 times more likely to have vomited (aOR = 2.99 95% CI: 1.58-5.64; p = 0.001). Participants knowing of dengue (aOR = 0.53 95% CI: 0.29-0.98; p = 0.042) and those coinfected with malaria (aOR = 0.28 95% CI: 0.14-0.57; p < 0.001) instead had reduced odds of dengue.

CONCLUSION

The study revealed a relatively high prevalence of symptomatic dengue fever among adults in the Central Region of Burkina Faso in 2022. These findings emphasize the need for continuous surveillance and targeted control measures. The low coinfection of dengue and malaria warrants further investigation.

Emerging Infectious Diseases Are Virulent Viruses-Are We Prepared? An Overview

The recent pandemic caused by SARS-CoV-2 affected the global population, resulting in a significant loss of lives and global economic deterioration. COVID-19 highlighted the importance of public awareness and science-based decision making, and exposed global vulnerabilities in preparedness and response systems. Emerging and re-emerging viral outbreaks are becoming more frequent due to increased international travel and global warming. These viral outbreaks impose serious public health threats and have transformed national strategies for pandemic preparedness with global economic consequences. At the molecular level, viral mutations and variations are constantly thwarting vaccine efficacy, as well as diagnostic, therapeutic, and prevention strategies. Here, we discuss viral infectious diseases that were epidemic and pandemic, currently available treatments, and surveillance measures, along with their limitations.

Seroprevalence of Dengue and Chikungunya Virus Infections in Children Living in Sub-Saharan Africa: Systematic Review and Meta-Analysis

Dengue and chikungunya viruses are frequent causes of malarial-like febrile illness in children. The rapid increase in virus transmission by mosquitoes is a global health concern. This is the first systematic review and meta-analysis of the childhood prevalence of dengue and chikungunya in Sub-Saharan Africa (SSA). A comprehensive search of the MEDLINE (Ovid), Embase (Ovid), and Cochrane Library (Wiley) databases was conducted on 28 June 2019, and updated on 12 February 2022. The search strategy was designed to retrieve all articles pertaining to arboviruses in SSA children using both controlled vocabulary and keywords. The pooled (weighted) proportion of dengue and chikungunya was estimated using a random effect model. The overall pooled prevalence of dengue and chikungunya in SSA children was estimated to be 16% and 7%, respectively. Prevalence was slightly lower during the period 2010-2020 compared to 2000-2009. The study design varied depending on the healthcare facility reporting the disease outbreak. Importantly, laboratory methods used to detect arbovirus infections differed. The present review documents the prevalence of dengue and chikungunya in pediatric patients throughout SSA. The results provide unprecedented insight into the transmission of dengue and chikungunya viruses among these children and highlight the need for enhanced surveillance and controlled methodology.

Setting Dengue Fever Epidemic Thresholds Between 2016 and 2021 in the Central Health Region, Burkina Faso: An Ecological Study

BACKGROUND

Dengue fever (DF) is endemic in Burkina Faso, with 70% of its burden supported by the Central Health Region. Then, a single confirmed case can no longer mean an epidemic. This study aimed at describing trends and setting epidemic thresholds of DF in the Central Health Region.

DATA AND METHODS

An ecological study was conducted using monthly data from DF surveillance between 2016 and 2021. Three methods were applied to set alert and intervention thresholds of DF monthly incidence rate: mean [mean + 2 SD], median [3rd quartile] and cumulative sum (C-sum) [C-sum + 1.96 SD]. These thresholds were plotted with the monthly incidence rates for 2021.

RESULTS

In total, 54,429 cases were reported between 2016 and 2021. Dengue cases increased biannually. The median annual incidence rate did not vary significantly across years [Kruskal-Wallis: χ2(5) = 9.825; p = 0.0803]. Within a year, the monthly incidence rate fell under 48.91 cases per 100,000 inhabitants between January and September and peaked in October or November. With the mean and C-sum methods, the 2021 monthly incidence rate remained below the intervention thresholds (Mean + 2 SD and C-sum + 1.96 SD). With the median method, the incidence rate exceeded the alert and intervention thresholds in July-September 2021.

CONCLUSIONS

If the DF incidence varied within a year due to the seasons, it was relatively stable between 2016 and 2021. The mean and C-sum methods based on the mean were subject to extreme values, giving high thresholds. The median method seemed better for capturing the abnormal increase in dengue incidence.

Blood components requirement in Brazilian dengue outbreaks: A retrospective analysis between 2008 to 2019

INTRODUCTION

Dengue is the most fatal virus disease spread by mosquito bites and Aedes aegypti is the main transmitting agent. It is an endemic disease in the tropical and subtropical regions, currently affecting more than 100 countries. Although most patients present mild forms of the disease, a considerable proportion of individuals has severe alterations in the blood count. The aim of this study was to evaluate the consumption pattern of blood components in epidemic and non-epidemic periods and to verify if there was an impact on dengue cases and the death rate.

METHOD

This is a retrospective cross-sectional study conducted through the collection and analysis of data from the Brazilian Ministry of Health from 2008 to 2019 on new cases and deaths from dengue, as well as the consumption of blood components in the period mentioned by hemovigilance bulletins of the Brazilian authority.

RESULTS

Regarding the results, no significant difference was found between the absolute amount of blood components used in years with an epidemic peak. Regarding the relative values, an important variation was shown among the distributive consumption patterns of blood components in the outbreak years. In the univariate linear regression analysis, there was statistical significance between the increase in the number of dengue cases and deaths from dengue with the increase in the consumption of red blood cell concentrates (RBP), platelet concentrates (PP), fresh frozen plasma (FFP) and cryoprecipitate (Cryo) (p-value < 0.05). The increase in dengue cases was related to the increase in Cryo consumption with clinical significance (R² > 0.5), but dengue deaths were not correlated to the same. In multivariate analysis, all regression models had clinical and statistical significance.

CONCLUSION

The data obtained in the present study demonstrate that there is a relevant relationship between the increase in cases and deaths from dengue with the blood components usage, especially PP, FFP and cryoprecipitate.

Evolving dynamics of Aedes-borne diseases in Africa: a cause for concern

Aedes-borne viruses, yellow fever (YF), dengue, Chikungunya and Zika are taking a huge toll on global health as Africa faces re-emergence with potential for massive human catastrophe. Transmission driven by diverse vectors in ecological settings that range from urban to rural and sylvatic habitats with human and nonhuman primate/reservoir activities across such habitats has facilitated virus movement and spillover to susceptible human populations. Approved vaccine exists for YF, although availability for routine and mass vaccination is often constrained. Integrating vector surveillance, understanding disease ecology with rationalised vaccination in high-risk areas (YF) remains important in disease prevention and control. We review trends in disease occurrence in Africa, hinting on gaps in disease detection and management and the prospects for prevention and/or control.

Serological Evidence of Zika Virus Circulation in Burkina Faso

Zika virus (ZIKV) and dengue virus (DENV) are two closely related members of the Flaviviridae family, both transmitted by mosquitoes of the genus Aedes, and are among the arboviruses most at risk to human health. Burkina Faso has been facing an upsurge in DENV outbreaks since 2013. Unlike DENV, there is no serological evidence of ZIKV circulation in humans in Burkina Faso. The main objective of our study was to determine the seroprevalence of ZIKV and DENV in blood donors in Burkina Faso. A total of 501 donor samples collected in the two major cities of the country in 2020 were first tested by a competitive enzyme-linked immunosorbent assay to detect flavivirus antibodies. Positive sera were then tested using Luminex to detect ZIKV and DENV antibodies and virus-specific microneutralization tests against ZIKV were performed. The ZIKV seroprevalence was 22.75% in the donor samples and we found seropositivity for all DENV-serotypes ranging from 19.56% for DENV-1 to 48.86% for DENV-2. Molecular analyses performed on samples from febrile patients and Aedes aegypti mosquitoes between 2019 and 2021 were negative. Our study showed the important circulation of ZIKV and DENV detected by serology although molecular evidence of the circulation of ZIKV could not be demonstrated. It is essential to strengthen existing arbovirus surveillance in Burkina Faso and more broadly in West Africa by focusing on fevers of unknown origin and integrating vector surveillance to assess the extent of ZIKV circulation and identify the circulating strain. Further studies are needed to better understand the epidemiology of this virus in order to define appropriate prevention and response methods.

Seroepidemiological Reconstruction of Long-term Chikungunya Virus Circulation in Burkina Faso and Gabon

Chikungunya virus (CHIKV) is a major public health concern worldwide. However, infection levels are rarely known, especially in Africa. We recruited individuals from Ouagadougou, Burkina Faso and Lambaréné, Gabon (age range, 1-55 years), tested their blood for CHIKV antibodies, and used serocatalytic models to reconstruct epidemiological histories. In Ouagadougou, 291 of 999 (29.1%) individuals were seropositive, ranging from 2% among those aged <10 years to 66% in those aged 40-55 years. We estimated there were 7 outbreaks since the 1970s but none since 2001, resulting in 600 000 infections in the city, none of which were reported. However, we could not definitively conclude whether infections were due to CHIKV or o'nyong-nyong, another alphavirus. In Lambaréné, 117 of 427 (27%) participants were seropositive. Our model identified a single outbreak sometime since 2007, consistent with the only reported CHIKV outbreak in the country. These findings suggest sporadic outbreaks in these settings and that the burden remains undetected or incorrectly attributed.

[Dengue virus circulation in West Africa: An emerging public health issue]

Dengue is the most widespread arbovirosis in the world, with approximately 390 million cases per year, 96 millions of which have clinical manifestations and 25,000 deaths. In West Africa, the circulation of this virus in human populations was first reported in the 1960s in Nigeria. Clinical diagnosis of dengue in West Africa is made difficult by the existence of other diseases with similar clinical presentations. Biological diagnosis remains therefore the only alternative. This biological diagnosis requires high quality equipment and well-trained personnel, which are not always available in resource-limited countries. Thus, many cases of dengue fever are consistently reported as malaria, leading to mismanagement, which can have serious consequences on the health status of patients. It is therefore necessary to set up surveillance systems for febrile infections of unknown origin in Africa by strengthening the diagnostic capacities of national laboratories.

Epidemiology and Laboratory Diagnostics of Dengue, Yellow Fever, Zika, and Chikungunya Virus Infections in Africa

Arbovirus infections are widespread, and their disease burden has increased in the past decade. In Africa, arbovirus infections and fever with unknown etiology are common. Due to the lack of well-established epidemiologic surveillance systems and accurate differential diagnosis in most African countries, little is known about the prevalence of human arbovirus infections in Africa. The aim of this review is to summarize the available epidemiological data and diagnostic laboratory tools of infections with dengue, yellow fever, Zika, and chikungunya viruses, all transmitted by Aedes mosquitoes. Studies indicate that these arboviral infections are endemic in most of Africa. Surveillance of the incidence and prevalence of the infections would enable medical doctors to improve the diagnostic accuracy in patients with typical symptoms. If possible, arboviral diagnostic tests should be added to the routine healthcare systems. Healthcare providers should be informed about the prevalent arboviral diseases to identify possible cases.

Estimating the Force of Infection for Dengue Virus Using Repeated Serosurveys, Ouagadougou, Burkina Faso

Because of limited data on dengue virus in Burkina Faso, we conducted 4 consecutive age-stratified longitudinal serologic surveys, ≈6 months apart, among persons 1–55 years of age, during June 2015–March 2017, which included a 2016 outbreak. The seroconversion rate before the serosurvey enrollment was estimated by binomial regression, taking age as the duration of exposure, and assuming constant force of infection (FOI) over age and calendar time. We calculated FOI between consecutive surveys and rate ratios for potentially associated characteristics based on seroconversion using the duration of intervals. Among 2,897 persons at enrollment, 66.3% were IgG-positive, and estimated annual FOI was 5.95%. Of 1,269 enrollees participating in all 4 serosurveys, 438 were IgG-negative at enrollment. The annualized FOI ranged from 10% to 20% (during the 2016 outbreak). Overall, we observed high FOI for dengue. These results could support decision-making about control and preventive measures for dengue.

A 5-year study of dengue seropositivity among suspected cases attending a teaching hospital of North-Western region of India

Dengue virus infection is estimated to cause infection in approximately 390 million people globally each year, of which 96 million develop clinical disease. Dengue serotype 2 (DEN-2) is the most prevalent serotype over the past 50 years in India, but serotypes 3 and 4 have appeared in some epidemics as well. A retrospective study was conducted in a teaching hospital, western India, between January 2014 and December 2018. The records of dengue serological test were analyzed. In total, 40 randomly selected nonstructural protein 1 (NS1) antigen-positive samples were analyzed by a reverse transcription-polymerase chain reaction. The demographic data, that is, age and sex, along with geographic location and platelet count level, were recorded from the Serology laboratory register and Hospital Information System. In total, 14.85% (735/4948) samples tested positive for dengue serology. Most of the laboratory-confirmed dengue cases, 34.97% (257/735), were observed in the 21-30 years of age group. The most common serotype detected in the tested samples was DEN-3 in 55% cases (22/40, 13 monoinfection and 9 coinfection with DEN-1 and DEN-2). The present study gives an insight into the trend of dengue seropositivity among suspected cases in the western part of Rajasthan, India. This study showed a higher seroprevalence of dengue infection as well as a gradual increase in the seroprevalence in this part of India.

Dengue Virus Infection in Sub-Saharan Africa Between 2010 and 2020: A Systematic Review and Meta-Analysis

Dengue virus (DENV) infection has garnered a global interest in the past few decades. Nevertheless, its epidemiology in certain developing and low-income regions remains poorly understood, due to the absence of comprehensive surveillance and reporting systems. This systematic review and meta-analysis aimed to determine the prevalence of DENV infection in the population of Sub-Saharan Africa using DENV infection markers, and to track any changes in its prevalence during the past ten years. It was conducted in accordance with the PRISMA guidelines, targeting the literature available at MEDLINE/PubMed, ScienceDirect, Cochrane library and Google Scholar. All articles published in English language between January 2010 and June 2020 were screened for eligibility. Random effects model was used to calculate the pooled prevalence of all infection markers. The Inconsistency Index (I²) was used to assess the level of heterogeneity between studies. Subgroup analysis according to country and time-frame of studies was conducted to provide possible explanations to substantial heterogeneity. The critical appraisal tool for prevalence studies designed by the Joanna Briggs Institute (JBI) was used to assess the risk of bias in all included studies. A total of 84 articles, covering 21 countries, were included in this review. Quantitative meta-analysis estimated a pooled IgG prevalence of 25% (95% CI: 21-29%, I² = 99%), a pooled IgM prevalence of 10% (95% CI: 9-11%, I² = 98%) and a pooled DENV RNA prevalence of 14% (95% CI: 12-16%, I² = 99%). Evidence for possible publication bias was also found in all three meta-analyses. Subgroup analysis according to the time of sample collection was performed to closely track the changing prevalence of DENV infection markers between 2010 and 2019. This meta-analysis estimates a high prevalence of DENV infection in Sub-Saharan Africa. More cost-efficient vector control strategies should be designed and implemented in order to adapt to the low-resource nature of this region.

Identification of Pathogens Potentially Associated with Non-Malarial Fever in Children: A Pilot Study in Peri-Urban Dakar, Senegal

Fever is one of the most common reasons for pediatric consultation in Africa. Malaria incidence has now dropped considerably, yet etiologies of non-malarial febrile diseases are poorly documented. This pilot study aimed to 1) identify pathogens potentially associated with non-malarial fever in children younger than 10 years in the suburbs of Dakar and 2) describe the epidemiological characteristics of these patients. During the study period, all eligible children (< 10 years of age, body temperature ≥ 38°C, negative result for the malaria rapid diagnostic test, living in Guediawaye/Pikine for the previous four calendar months, not receiving any anti-infectious treatment since the onset of fever, and with parent's consent to participate) presenting to the health post in Medina Gounass located in Guediawaye on Mondays and Fridays were included. In total, 106 children participated in the study, and PCR from nasopharyngeal swabs, hemoculture, C-reactive protein, blood cell counts, and quantitative buffy coat from blood samples and coproculture from stool samples were performed. In 70 (66%) children, at least one pathogen was isolated. Viruses were identified in 55 children, most commonly enteroviruses, rhinoviruses, and adenoviruses, and dengue virus was identified in three children. Only five children had bacterial infections, and 10 had bacterial and viral coinfections. Ninety-seven children (92%) received prescription for antibiotics. Many strains of bacteria were found to be resistant to several antibiotics. Despite limitations, this pilot study showed that pathogens potentially associated with non-malarial fever in children younger than 10 years near Dakar were predominantly viruses, most commonly upper respiratory infections, although bacteria accounted for a small proportion.

Effect of a free healthcare policy on health services utilisation for non-malarial febrile illness by children under five years in Burkina Faso: an interrupted time series analysis

OBJECTIVE

To assess the effect of a free healthcare policy for children under five years old implemented in Burkina Faso since April 2016, on the use of health care of non-malarial febrile illnesses (NMFI).

METHODS

To assess the immediate and long-term effect of the free healthcare policy in place, we conducted an interrupted time series analysis of routinely collected data on febrile illnesses from three urban primary health centres of Ouagadougou between 1 January 2015 and 31 December 2016.

RESULTS

Of the 39 046 febrile cases reported in the study period, 17 017 NMFI were included in the study. Compared to the period before the intervention, we observed an immediate, non-statistically significant increase of 7% in the number of NMFI (IRR = 1.07; 95% CI = 0.75, 1.51). Compared to the trend that would have been expected in absence of the intervention, the results showed a small but sustained increase of 6% in the trend of monthly number of NMFI during the intervention period (IRR = 1.06; 95%CI = 1.01, 1.12).

CONCLUSION

Our study highlighted an increase in the uptake of healthcare services, specifically for NMFI by children under five years of age, after the implementation of a free care policy. This analysis contributes to informing decision makers on the need to strengthen the capacities of healthcare centres and to anticipate the challenges of the sustainability of this policy.

The epidemiology of dengue outbreaks in 2016 and 2017 in Ouagadougou, Burkina Faso

Background

Dengue is prevalent in as many as 128 countries with more than 100 million clinical episodes reported annually and four billion people estimated to be at risk. While dengue fever is systematically diagnosed in large parts of Asia and South America, the disease burden in Africa is less well investigated. This report describes two consecutive dengue outbreaks in Ouagadougou, Burkina Faso in 2016 and 2017.

Methods

Blood samples of febrile patients received at Schiphra laboratory in Ouagadougou, Burkina Faso, were screened for dengue infection using SD Bioline Dengue Duo rapid diagnostic test kits (Standard Diagnostics, Suwon, Republic of Korea).

Results

A total of 1,397 and 1,882 cases were reported by a single laboratory in 2016 and 2017, respectively. Most cases were at least 15 years of age and the results corroborated reports from WHO indicating the circulation of three dengue virus serotypes in Burkina Faso.

Conclusion

This study complements data from other, simultaneously conducted surveillance efforts, and indicates that the dengue disease burden might be underestimated in sub-Saharan African nations. Dengue surveillance should be enhanced in African settings to determine the burden more accurately, and accelerated efforts towards a dengue vaccine should be put in place.

Video as a public health knowledge transfer tool in Burkina Faso: A mixed evaluation comparing three narrative genres

BACKGROUND

The dengue virus is endemic in many low- and middle-income countries. In Burkina Faso, the proportion of fevers that could be due to dengue is growing. In 2013, a dengue epidemic spread there, followed by other seasonal outbreaks. Dengue is often confused with malaria, and health workers are not trained to distinguish between them. Three training videos using different narrative genres were tested with nursing students from two institutions in Ouagadougou: journalistic, dramatic and animated video. The study aimed to determine if video is an effective knowledge transfer tool, if narrative genre plays a role in knowledge acquisition, and which narrative elements are the most appreciated.

METHODOLOGY

A mixed method research design was used. The relative effectiveness of the videos was verified through a quasi-experimental quantitative component with a comparison group and post-test measurements. A qualitative component identified participants' perceptions regarding the three videos. Data were drawn from a knowledge test (n = 482), three focus groups with health professionals' students (n = 46), and individual interviews with health professionals (n = 10). Descriptive statistics and single-factor variance analysis were produced. A thematic analysis was used to analyse qualitative data.

PRINCIPAL FINDINGS

Results showed that all three videos led to significant rates of knowledge improvement when compared with the comparison group (p <0.05): 12.31% for the journalistic video, 20.58% for the dramatic video, and 18.91% for the animated video. The dramatic and animated videos produced a significantly higher increase in knowledge than did the journalistic video (with respectively 8.27% (p = 0.003) and 6.59% (p = 0.029) and can be considered equivalent with a difference of 1.68% (p = 0.895). Thematic analysis also revealed that these two videos were considered to be better knowledge transfer tools. Four key aspects are important to consider for a video to be effective: 1) transmitting information in a narrative form, 2) choosing good communicators, 3) creating a visual instrument that reinforces the message and 4) adapting the message to the local context.

CONCLUSIONS

Video has proven to be an effective and appreciated knowledge transfer and training tool for health professionals, but the narrative genre of the videos can influence knowledge acquisition. The production of other videos should be considered for training or updating health professionals and their narrative genre taken into consideration. The actual context of constant circulation of new diseases, such as COVID-19, reaffirms the need to train health professionals.

Analysis of the implementation of a community-based intervention to control dengue fever in Burkina Faso

BACKGROUND

A community-based dengue fever intervention was implemented in Burkina Faso in 2017. The results achieved vary from one area to another. The objective of this article is to analyze the implementation of this intervention, to better understand the process, and to explain the contextual elements of performance variations in implementation.

METHODOLOGY

The research was conducted in the former sector 22 of the city of Ouagadougou. We adapted the Consolidated Framework for Implementation Research (CFIR) to take into account the realities of the context and the intervention. The data collected from the participants directly involved in the implementation using three techniques: document consultation, individual interview, and focus group.

RESULTS

Two dimensions of CFIR emerge from the results as having had a positive influence on the implementation: (i) the characteristics of the intervention and (ii) the processes of the intervention implementation. The majority of the CFIR constructions were considered to have had a positive effect on implementation. The quality and strength of the evidence received the highest score. The dimension of the external context had a negative influence on the implementation of the intervention.

CONCLUSION

The objective of the study was to analyze the influence of contextual elements on the implementation process of a community-based dengue fever intervention. We used the CFIR framework already used by many studies for implementation analysis. Although it was not possible to test this framework in its entirety, it is useful for the analysis of the implementation. Its use is simple and does not require any special skills from users. Usability is indeed an essential criterion for the relevance of using an analytical framework in implementation science.