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Abstract
Introduction Equitable access to vaccines for migrants and refugees is necessary to ensure their right to health and to achieve public health goals of reducing vaccine-preventable illness. Public health policies require regulatory frameworks and communication to effect uptake of effective vaccines among the target population. In Colombia, the National COVID-19 Vaccination Plan implicitly included Venezuelan refugees and migrants; however, initial communication of the policy indicated that vaccine availability was restricted to people with regular migration status. We estimated the impact of a public announcement, which clarified access for refugees and migrants, on vaccination coverage among Venezuelans living in Colombia.
Methods Between 30 July 2021 and 5 February 2022, 6221 adult Venezuelans participated in a cross-sectional, population-based health survey. We used a comparative cross-sectional time-series analysis to estimate the effect of the October 2021 announcement on the average biweekly change in COVID-19 vaccine coverage of Venezuelans with regular and irregular migration status.
Results 71% of Venezuelans had an irregular status. The baseline (preannouncement) vaccine coverage was lower among people with an irregular status but increased at similar rates as those with a regular status. After the announcement, there was a level change of 14.49% (95% CI: 1.57 to 27.42, p=0.03) in vaccination rates among individuals with irregular migration status with a 4.61% increase in vaccination rate per biweekly period (95% CI: 1.71 to 7.51, p=0.004). By February 2022, there was a 26.2% relative increase in vaccinations among individuals with irregular migration status compared with what was expected without the announcement.
Conclusion While there was no policy change, communication clarifying the policy drastically reduced vaccination inequalities across migration status. Lessons can be translated from the COVID-19 pandemic into more effective global, regional and local public health emergency preparedness and response to displacement.
- COVID-19
- Vaccines
- Health policies and all other topics
Data availability statement
Data are available upon reasonable request. Deidentified individual data and data dictionary will be made available upon reasonable request after approval of a proposal and signing of a data use agreement. Requests for data sharing can be sent to Dr Andrea Wirtz (awirtz1@jhu.edu) and will be reviewed by study team members from the collaborating organisations, Johns Hopkins University, Red Somos and the Ministry of Health and Social Protection.
This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.
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What is already known on this topic
Historically, displaced populations (broadly inclusive of migrants, refugees, asylum seekers and other displaced people) have faced myriad barriers to health services, including preventative services and vaccination.
A systematic review by Abba-Aji and colleagues reported that the majority of studies published between January 2020 and October 2021 were from high-income countries and described significant barriers to COVID-19 vaccination and some vaccine hesitancy among some ethnic minority groups.
Less data are available on vaccine coverage among refugees and migrants in low-income or middle-income countries, including within the Latin American and Caribbean region, which has experienced a 107% increase in the number of international migrants in the past decade.
Case studies and reviews by Perez-Brumer and colleagues and Bojorquez-Chapela and colleagues and a report developed for Lancet Migration described and compared national COVID-19 vaccination policies and implementation as they related to refugees and migrants in several countries in the Latin American region.
WHAT THIS STUDY ADDS
We analysed how public health communication of a COVID-19 policy, which remains unchanged, affected vaccination coverage among Venezuelan refugees and migrants. Specifically, Colombia’s National COVID-19 Vaccination Plan implicitly included Venezuelan refugees and migrants; however, initial communication restricted availability to people with regular migration status.
Using data from 6221 Venezuelan refugees and migrants who participated in a health survey between July 2021 and February 2022, we found that vaccination coverage was lower among people with an irregular migration status compared with those with a regular migration status.
A public announcement in October 2021 that clarified access for people with an irregular migration status resulted in a 26% relative increase in vaccination coverage among Venezuelans with an irregular migration status in Colombia compared with what was expected without the announcement.
This study provides novel data on COVID-19 vaccination coverage among Venezuelan refugees and migrants and vaccination inequalities associated with migration status. We found that while there was no policy change, communication clarifying the policy drastically reduced vaccination inequalities across migration status.
HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY
Public health policies for migrants and refugees at a national level, like all public policies in general, require the construction and development of regulatory frameworks.
Effective implementation of policy and regulatory frameworks requires clear communication to mobilise all actors involved in the policy and ensure awareness and uptake among the target population.
While the COVID-19 emergency has ended, lessons can be translated from the COVID-19 pandemic to more effective global, regional and local public health emergency preparedness and response to displacement.
Introduction
Historically, displaced populations (broadly inclusive of migrants, refugees, asylum seekers and other displaced people) have faced myriad barriers to health services, some related to regulations in the host countries1 and others to social factors such as low income, language barriers, discrimination and low awareness of rights.2 During the COVID-19 pandemic, refugees and migrants generally experienced greater difficulties in accessing health services that deepened existing inequalities.3 Though data on access to COVID-19 vaccination by migrant and refugee populations are largely limited to high-income settings,4 5 these negative impacts may have been greater in low-income and middle-income receiving countries,6 where there was a low supply of vaccination that resulted from the global inequality in vaccine distribution early in the response.7 In Latin America, the inclusion of refugees and migrants in NVPs for COVID-19 was variable and evolved over time, such that refugees and migrants were explicitly included in some country plans, included depending on migration status or initially excluded.8 9
The ongoing crisis in Venezuela has resulted in one of the largest, ongoing human displacements in the world. Over 7 million Venezuelans have been displaced as of August 2023; about 2.89 million of whom have migrated to Colombia, which serves as the main receiving country.10 The rapid arrival of Venezuelan refugees and migrants (regional response uses the terms ‘refugees and migrants’ in recognition of the complex situation) in Colombia migration has represented a challenge for the country’s health system,11 which was potentially exacerbated during the COVID-19 pandemic.12 Colombia has implemented a health sector response plan to the migration phenomenon since 2017.13 During the COVID-19 pandemic, Colombia also made a great effort to guarantee the inclusion of migrants in health services, such as urgent clinical care and access to diagnostic tests.14 Taking into account the humanitarian crisis, in 2017, the Constitutional Court of Colombia advanced the protection of Venezuelan migrants’ health by using the constitutional principle of solidarity to rule that migrants have the right to receive basic and urgent care in Colombia, regardless of migration status.15
At the end of January 2021, Colombia designed a National Vaccination Plan (NVP), which described the plan’s target population as broadly inclusive of the country’s ‘inhabitants’, which tacitly but not explicitly included migrants.16 However, when the plan was announced, the then-president of the Republic of Colombia announced that refugees and migrants (about 2 million in 2021) would not be included in the plan, though clarified that Venezuelans with a regular status would be eligible.17 Through some subsequent modifications of the NVP, the regulatory framework later evolved to facilitate their inclusion or even to include them more explicitly (figure 1). In August 2021, the first regulation was issued that allowed people who lived in the country and who do not have an identity document issued by the Colombian State to register for COVID-19 vaccination, though there was no public communication to this effect.18 In October 2021, sites were opened to explicitly provide vaccination to Venezuelans without the required demonstration of legal documents, and the Ministry of Health and Social Protection announced that vaccination was available to all Venezuelans, regardless of migration status.19 20 The Ministry of Health and Social Protection published the announcement on its official website and sent a press release to media outlets for dissemination after the Unified Command Post, a weekly event that involved health secretariats, the minister and the vice minister. Later in December 2021, people located in the border areas were explicitly included as part of the population target of the NVP against COVID-19.21 We aimed to analyse the impact that public health policy and communication may have had on inequalities in vaccination coverage against COVID-19 among Venezuelan migrants by migration status, during the first year of implementation of the NVP in Colombia.
Timeline of the implementation and communication of the National Vaccination Plan against COVID-19 (2020–2022).
Methods
We used data from a biobehavioural, cross-sectional health survey among Venezuelan refugees and migrants in Colombia. The study was an interdisciplinary collaboration between a community-based organisation, Red Somos, academic partner, Johns Hopkins University and the Colombian Ministry of Health and Social Protection. Implementation was preceded by qualitative, formative research.22 Study methods have been previously described.23 24
Study design and participants
The study was implemented in two sites encompassing four cities: (1) Bogotá and Soacha, Cundinamarca Department, and (2) Barranquilla and Soledad, Atlántico Department, which have some of the largest distributions of Venezuelans in the country. Cities within each site were geographically adjacent to each other, and there was regular mobility across city locales by the Venezuelan and host communities. Locations were selected for the population distribution, accessibility to humanitarian and health programmes, and lower presence of migrants who were pendular or transiting through Colombia to another destination. Participants were sampled using respondent-driven sampling (RDS) from 30 July 2021 through 5 February 2022 and completed a single study visit.
Candidates were eligible for participation according to the following criteria: aged ≥18 years, self-reported birth in Venezuela and Venezuelan nationality, migrated to Colombia as of 2015 or later, currently resided in a study city, no reported intention to migrate out of Colombia (ie, transiting), no prior participation and displayed a valid study coupon at enrolment. Enrolment was restricted to only one member of an immediate family. Eligible participants underwent screening and written consent in private study offices.
Procedures
Participants identified with low literacy or uncomfortable with technology completed an electronic, staff-administered questionnaire. All others completed electronic, self-administered questionnaires with staff support. We used this multimodal collection approach to minimise COVID-19 transmission risk. It also served to demonstrate respect for participant literacy and preferences and followed best practices in the development and implementation of multimodal survey research.25
Measures used in the survey questionnaire were drawn from existing and validated measures where possible and relevant to the population. Survey modules included the following domains: demographics, displacement experiences and migration status, food security, health history including healthcare utilisation, use of humanitarian services and social network size questions used for RDS weighting procedures.26
In Colombia, access to health insurance is dependent on one’s migration status. People with a regular status (ie, possess any unexpired document permitting stay in Colombia) can access insurance, and thus healthcare, through formal employment or the subsidised system. Those with an irregular status (ie, no possession of legal documents permitting stay in Colombia) cannot access health insurance and so have limited access only to emergency services and prenatal care. Migration status was self-reported at the time of the study and classified as regular or irregular migration status. Individuals in the process of obtaining documents may report irregular status.
COVID-19 measures included self-reported history of COVID-19-like symptoms based on Centers for Disease Control and Prevention (CDC)-reported symptomatology at the time of the study, diagnosis of COVID-19, the number of people in household diagnosed with COVID-19, the number of household deaths attributed to COVID-19 and history of COVID-19 vaccination, including first dose, second dose as applicable, vaccine manufacturer, interest in vaccination if not vaccinated, reasons for non-vaccination and reasons for disinterest in vaccination.
Institutional and ethical review of the study was conducted by the Ethics Review Committee at the Universidad El Bosque in Bogotá, Colombia, and the Institutional Review Board at Johns Hopkins School of Public Health, USA. The protocol was also reviewed in accordance with CDC human research protection procedures. Participants were provided with referrals as needed for health and humanitarian services. To mitigate risks associated with the ongoing pandemic, study implementation followed approved biosecurity protocols and local COVID-19 policies.
Statistical analyses
Descriptive analyses were performed to estimate the prevalence of key demographic and health characteristics of the population. Descriptive analyses included unweighted sample and RDS-weighted population-based estimates.27
We evaluated the association between migration status and the receipt of at least one COVID-19 vaccination using Poisson regression models with robust variances. Adjusted and unadjusted prevalence ratios were calculated, controlling for demographic characteristics, COVID-19 history and participation before versus on or after 8 October 2021, which was the date of news reports that indicated the availability of vaccines to migrants regardless of migration status.19 20 We tested effect modification between migration status and the date of the October public announcements using an interaction term for migration status and date of participation before or after the October public announcements. We built Poisson regression models stratified by migration status to assess whether the relationship between the date of press release and COVID-19 vaccination was modified by migration status. We selected the final model based on fit using the Akaike Information Criterion and assessed for collinearity by examining the variance inflation factor.
We used a comparative cross-sectional time-series (CSTS) design to estimate the effect of the October public announcement on the main outcome: average biweekly change in the proportion of Venezuelans with regular and irregular migration status who received a COVID-19 vaccine, defined as self-reporting receipt of at least one dose of the COVID-19 vaccine. A CSTS analysis allows us to draw causal inferences about an intervention (ie, October public announcement) and outcome (ie, COVID-19 vaccination) by using a comparison group with a comparable level or trend change prior to the intervention. We selected people with regular migration status as a comparison group to control for measured time-varying confounders and underlying temporal trends, assuming that Venezuelans with regular migration status would be unaffected by the October 2021 public announcements.28 To estimate the causal effect of the October public announcements on the reduction of vaccine coverage inequalities among migrants, the baseline level change in the proportion of vaccinations among individuals with an irregular migration status must differ significantly from individuals with a regular migration status and have comparable level and trend changes between groups post-October public announcement. By including individuals with a regular migration status as a comparable comparison group in terms of level and trend changes, we assume exchangeability and exposure to the intervention to be random.29
The CSTS model included three covariates: a time variable, defined as a biweekly average change in the proportion of migrants vaccinated; an intervention variable, assigned as the first biweekly interval after the October 2021 public announcement to indicate the pre-public and post-public announcement periods; a group variable, individuals with an irregular migration status compared with individuals with a regular migration status; and variables for their interactions. Potential autocorrelation and heteroskedasticity were addressed by using Newey-West standard errors without a lag. All data management and statistical analyses were performed using Stata SE 17.0 (StataCorp).
Results
Between July 2021 and February 2022, 6221 Venezuelan refugees and migrants were enrolled in the study; of these, 1781 (29%) participated before 8 October 2021, and 4431 (71%) participated on 8 October 2021 and after. Of the total study population, 71% had an irregular migration status. Table 1 displays sample and population estimates of demographic characteristics and COVID-19 health and infection history stratified by migration status. Two-thirds of migrants were female (65.6%), and the median age of participants was 32 years (IQR 26–41). While limited overall, Venezuelans with an irregular status compared with those with regular migration status had lower educational attainment (completed higher education: 18.4% vs 31.7%), lower literacy (high literacy score: 82.0% vs 88.7%) and higher levels of unemployment (43.9% vs 37.0%). Overall, receipt of at least one vaccine against COVID-19 was lower among Venezuelan migrants with an irregular status compared with those with a regular status (44.3% vs 55.2%).
Demographic characteristics of Venezuelan refugees and migrants living in four metropolitan areas of Colombia (n=6221), July 2021–February 2022
Table 2 displays the prevalence ratios for variables associated with receipt of at least one vaccination. People with a regular migration status had an overall adjusted prevalence of vaccination that was 3.4 times higher than individuals with irregular status (95% CI: 2.68 to 4.36; p<0.001). The prevalence of vaccination was 6.3 times greater among Venezuelans participating after the October announcement (95% CI: 5.08 to 7.69; p<0.001), and there was a significant interaction between migration status and date of participation (pre-October/post-October). COVID-19 vaccination was also associated with age, gender, employment, educational attainment, literacy and residency type in the adjusted model. There was no evidence of an association between self-reported chronic conditions, history of COVID-19 infection, the number of COVID-19 infections or deaths in the household attributed to COVID-19 and receipt of at least one vaccination. Online supplemental table 1 displays the same model stratified by migration status.
Supplemental material
Unadjusted and adjusted prevalence ratios of variables associated with receipt of at least one vaccination against COVID-19 among Venezuelan refugees and migrants in Colombia, July 2021 to February 2022 (n=6221)
Figure 2 displays the changes in the proportion of Venezuelans who reported at least one vaccination against COVID-19. Table 3 displays the baseline (pre-October announcements), post-October announcement trends and pre-trend and post-trend change. The baseline proportion of COVID-19 vaccination among Venezuelans with an irregular status was lower than among those with a regular status, 2.0% and 19.3%, respectively, with an absolute difference of −17.3% (95% CI: −24.0 to −10.6; p<0.001). The baseline biweekly vaccination trends were similar by migration status with vaccination, increasing at a rate of 5.1% among individuals with a regular migration status (95% CI: 2.2 to 7.9; p=0.002) and 4.1% among those with an irregular status (95% CI: 1.8 to 6.4; p=0.001). Despite the significant increase in vaccination rates among both groups, the proportion of vaccinated individuals with an irregular migration status before the October announcements remained lower than those with a regular migration status (30.4% vs 51.1%, not displayed). After the October announcements, there was an insignificant level and trend change in the absolute per cent difference between irregular and regular migration status groups of 8.9% (95% CI: −8.4 to 26.2; p=0.29) and 2.6% (95% CI: −1.5 to 6.7; p=0.19), respectively. Additionally, there was a level change of 14.5% (95% CI: 1.6 to 27.4; p=0.03) in vaccination rates among individuals with an irregular migration status with an increase in vaccination rates of 4.6% per biweekly period (95% CI: 1.7 to 7.5; p=0.004). By February 2022, the per cent vaccinated among individuals with an irregular migration status was 19.7% higher than would have been expected without the October announcements, representing a 26.2% relative increase in vaccinations among individuals with irregular migration status. We conducted a sensitivity analysis that repeated this analysis among a sample that restricted the sample to those who were vaccinated or were unvaccinated but reported interest in COVID-19 vaccination (2660 of 3244 unvaccinated) and found similar results (online supplemental table 2). Self-reported barriers to vaccination against COVID-19 among unvaccinated individuals are included in figure 3.
Supplemental material
Comparative cross-sectional interrupted time-series analysis of the effect of the National Vaccination Plan (NVP) press releases on the average biweekly changes in the proportion of Venezuelan refugees and migrants in Colombia who received at least one vaccination against COVID-19 between July 2021 and February 2022. Legend: the dashed black line represents the first biweekly interval after the initial October 2021 NVP press releases. Dots are the cross-sectional proportion of migrants vaccinated against COVID-19 within biweekly intervals.
Self-reported barriers to vaccination among unvaccinated Venezuelan refugees and migrants who were interested in receiving a vaccination against COVID-19 by migration status (n=2660). Note: data are per cent of individuals who self-reported each reason for not receiving a vaccine against COVID-19 despite interest in receiving a vaccination. Respondents could select more than one reason from the available options.
Vaccination coverage rates among Venezuelan refugees and migrants in Colombia during pre-October and post-October 2021 public announcement
Discussion
Retrospective analysis of the COVID-19 response can inform future public health responses and vaccine strategies. This is particularly relevant for future considerations of how to prevent inequalities in vaccine coverage and healthcare access for historically underserved and stigmatised populations, such as refugees and migrants, especially in low-income and middle-income countries where resources are relatively scarce. Our study was conducted in Colombia among Venezuelan refugees and migrants, one of the largest displaced groups globally but for whom little population-level data exist to evaluate their overall health status. While the study’s main objective was not intended to focus on vaccination coverage, the overlap of the study implementation with the rollout of the NVP provided an opportunity to evaluate how public health policies and communication of those policies over time may impact vaccination among refugees and migrants.
Specifically, the NVP made vaccination available to all ‘inhabitants’ of Colombia, thus implicitly available regardless of migration status. However, early communication by the administration suggested that it was only available to people with regular migration status. Our regression and CSTS analyses reflect this, showing that baseline vaccination was significantly lower among people with an irregular status compared with those with a regular status. As vaccines became increasingly available over time in Colombia, vaccination increased across both groups, though the overall proportions of people vaccinated remained lower among people with an irregular status prior to October 2021. The October 2021 public announcements clarified the availability of vaccination to Venezuelan refugees and migrants regardless of migration status, and our analysis demonstrated a significant increase in the overall proportion of refugees and migrants who reported receiving at least one vaccine against COVID-19. It is possible that the delay in communicating the explicit inclusion of migrants with irregular status in the NVP was due to the need to ensure the feasibility of their inclusion and then update specific regulatory frameworks.30 Ultimately, we found that the post-press release rate of coverage growth was higher among Venezuelans with an irregular status compared with those with a regular status. This is explained by the lower coverage pre-press release and the speed of vaccination among those with an irregular status once the enacted or perceived barriers for individuals with an irregular migration status were removed. Although vaccination proportions were consistently lower among individuals with an irregular migration status, the vaccination coverage gap was substantially reduced after the October public communications. Taken together, our study demonstrated that an inclusive policy coupled with explicit communication of the target population and eligibility resulted in an improvement in the proportion of refugees and migrants who received COVID-19 vaccinations, particularly those without regular migration status, which in turn led to more equitable coverage. Crucially, the role of clear communication in influencing implementation and health behaviours is highlighted here, as there was no policy change between the pre-October and post-October periods.
In Colombia, as in many countries,31 not having a regular migration status (ie, having an irregular status) creates additional challenges given the lack of insurance, which in this case permits access to vaccines only through local Secretariats of Health rather than through insurers, as would be possible for people with a regular status. Vaccine registration requirements made it more likely that people with an irregular status were identified and unable to register due to concern among local health authorities regarding how the vaccination would be paid by the central government to the providers.18 Although the policy of the NVP was broadly inclusive of inhabitants in Colombia, there were administrative barriers that the communication helped to reduce. This suggests that those involved in the implementation of public health policies may make decisions not only based on written regulations but also on public announcements. Likewise, clear public health communication of inclusive public health policies may generate trust and motivation among target populations.
Our findings reflect the myriad barriers that refugees and migrants face to effective access to vaccines and other health services. Venezuelans with an irregular status tend to have less income, lower education and literacy, which may lead to lower awareness of their rights than people with a regular status and exacerbate existing barriers to healthcare. Existing literature documents perceived stigma and discrimination among Venezuelan refugees and migrants in Colombia, including antimigrant perceptions within the healthcare system.22 This dynamic contextualises baseline levels of vaccination in the pre-press release period among this population. It also underscores the importance of unambiguous and intentional communication campaigns for migrant and refugee or otherwise marginalised populations.
Consistent with other studies globally, we found that vaccination coverage varied by age, gender, education, employment and literacy.31 32 Differences by age group are not unexpected, given the prioritisation of people with chronic health conditions and older populations for vaccine distribution according to the NVP in Colombia. In this study and others, women had lower vaccine coverage, which may anecdotally be explained by gender norms related to childcare and discouraged women from visiting vaccination clinics while caring for children.31 Venezuelans with higher literacy and education were more likely to receive at least one vaccination, suggesting that public health information and awareness-raising interventions that use other methods outside of written text may be needed to reduce vaccination inequalities. Finally, reduced vaccination among people in informal employment may be explained in part by lack of insurance but may also be explained by work closures during the pandemic and prioritisation of finding work above time spent accessing vaccination. Nonetheless, this suggests an opportunity to consider vaccination campaigns at locations where people may gather for informal employment as well as other innovative strategies for increasing the inclusion of migrants in public health programmes.
This study has several limitations. First, the study may not be representative at a national level, although the cities included have some of the highest proportions of refugees and migrants in the country; however, the RDS methodology, which samples the underlying social networks to approximate population estimates, likely improves representativeness. Further, demographic characteristics and population distributions (eg, migration status and age) are consistent with estimates reported by the national migration agency at the time of the study suggesting high internal validity. However, findings may not be generalisable to border areas with predominantly pendular or transit migration and where the impact of the policies could be different given that participation in this study was restricted to Venezuelans with plans for a long-term stay.
Finally, there are potential limitations associated with the CSTS analysis. First, a comparison group must be comparable to the intervention group. We did observe some demographic differences between people with regular and irregular status, though intervention and control group characteristics are not required to be balanced to predict the counterfactual.28 We also observed parallel trends between groups before the intervention (October public announcement), supporting the comparability of the two groups. Second, CSTS analyses are susceptible to history bias if another intervention or event co-occurs with the intervention of interest. It is impossible to isolate the effect of policy communication from other societal changes; however, since a significant effect was detected only among individuals with an irregular migration status, the significant postintervention level and trend changes among individuals with an irregular migration status may be attributed to the October announcements.28 Third, CSTS analyses do not control for unknown confounding. Nevertheless, a comparable comparison group enabled us to control for known and time-varying confounders, thereby increasing the validity of our study.
Conclusion
We observed that public health communication in Colombia that clarified the inclusion of refugees and migrants in the National COVID-19 Vaccination Plan may have improved COVID-19 vaccine coverage among Venezuelans. Clarification of the policy led to a significant change in vaccination coverage rates among people with an irregular status and drastically reduced vaccination inequalities across migration statuses. Our study provides evidence of the effects of inclusive policies coupled with public health communication to augment the dissemination of public health policies to the general public, health authorities, service providers and general stakeholders at the national and local levels, particularly during health emergencies. Ultimately, these findings demonstrate how lessons can be learnt from COVID-19 and translated into more effective global, regional and local public health public health emergency preparedness and response to displacement. Continued efforts to provide equitable access to vaccines for refugees and migrants are necessary to ensure their right to health, advance development goals of universal healthcare and achieve public health goals of reducing vaccine-preventable illness.
Data availability statement
Data are available upon reasonable request. Deidentified individual data and data dictionary will be made available upon reasonable request after approval of a proposal and signing of a data use agreement. Requests for data sharing can be sent to Dr Andrea Wirtz (awirtz1@jhu.edu) and will be reviewed by study team members from the collaborating organisations, Johns Hopkins University, Red Somos and the Ministry of Health and Social Protection.
Ethics statements
Patient consent for publication
Ethics approval
This study involves human participants and was approved by Ethics Review Committee at the Universidad El Bosque in Bogotá, Colombia (No. 022-2020) and the Institutional Review Board at Johns Hopkins School of Public Health, USA (IRB00011598). Participants gave informed consent to participate in the study before taking part.
Acknowledgments
Gratitude is extended to the thousands of Venezuelan refugees and migrants who participated in this study. This report would not have been possible without their participation and shared experiences. The study was implemented by a dedicated and compassionate team led by Red Somos including Cindy Quijano, Alejandra Vela, Yessenia Moreno, Francisco Rigual, Marlon Stwar Sierra, Luis Pérez, Edwin Ferney Ramos, Edenys Rangel, Karen Marivi Vera, Valentina Calderón Giraldo, Daniel Felipe Durán Mongua, Stefanie Perdomo Martín, Paula Rincón Giraldo, Heriberto Mejía, Luder Fuentes, Jesús Javier Sandoval, Indira Fuentes, Leives Jiménez, Esther María Beltrán, Rocío Pérez, Mayra de la Cruz, Byron Gutiérrez, Oladys Bolaño, Xiomara Barrios, José Amaris Povea, Nayrimi Andreina Valbuena Castillo, Rowel Vera, José Gregorio Nieves, Hendriel Briceño, Omany Fereira and Jesús Adelvi Rojas. We acknowledge with gratitude the support of colleagues at the US Centers for Disease Control and Prevention, Dante Bugli, Eva Leidman and Kevin Clarke; Johns Hopkins University, James Case, Kristin Bevilacqua and Sarah Arciniegas; and the United Nations High Commissioner for Refugees in Colombia, including Federico Duarte and Saskia Loochkartt.
Supplementary materials
Supplementary Data
This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.
Footnotes
WG and JAF-N are joint first authors.
Handling editor Vijay Kumar Chattu
Twitter @andrealwirtz
WG and JAF-N contributed equally.
Contributors ALW, JRG, MS, KRP, RLN and PS designed the study protocol and data collection instruments of original study. JRG and MABT led the study implementation; JO, JJL, DMP and JFRC oversaw data collection at study sites and laboratory procedures. RLN and JAF-N contributed expertise in public health policy. ALW provided oversight to the overall study with coordination with MS. WG designed the research question pertinent to this analysis and conducted the statistical analysis. ALW, WG and JAF-N designed the specific methodological approach for the analysis presented in this study. WG and JAF-N contributed to the documentary review and the establishment of vaccination milestones in Colombia. ALW, MS and WG had access to the data. WG, JAF-N, MS and ALW wrote the first draft of the manuscript and had responsibility for the decision to submit it for publication. ALW
accepts full responsibility for the work and the conduct of the study, had access to the data, and controlled the decision to publish. Data were available to all authors. All authors reviewed, contributed input and approved the manuscript for publication.
Funding This work was supported by the US President’s Emergency Plan for AIDS Relief (PEPFAR) through the Centers for Disease Control and Prevention (CDC) under the terms of Cooperative Agreement number NU2GGH002000-03-01. The contents of this manuscript are solely the responsibility of the authors and do not necessarily represent the official views of PEPFAR, the CDC or the Department of Health and Human Services.
Competing interests None declared.
Patient and public involvement Patients and/or the public were involved in the design, or conduct, or reporting, or dissemination plans of this research. Refer to the Methods section for further details.
Provenance and peer review Not commissioned; externally peer reviewed.
Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.