Inferring the risk factors behind the geographical spread and transmission of Zika in the Americas
- PMID: 29346387
- PMCID: PMC5790294
- DOI: 10.1371/journal.pntd.0006194
Inferring the risk factors behind the geographical spread and transmission of Zika in the Americas
Abstract
Background: An unprecedented Zika virus epidemic occurred in the Americas during 2015-2016. The size of the epidemic in conjunction with newly recognized health risks associated with the virus attracted significant attention across the research community. Our study complements several recent studies which have mapped epidemiological elements of Zika, by introducing a newly proposed methodology to simultaneously estimate the contribution of various risk factors for geographic spread resulting in local transmission and to compute the risk of spread (or re-introductions) between each pair of regions. The focus of our analysis is on the Americas, where the set of regions includes all countries, overseas territories, and the states of the US.
Methodology/principal findings: We present a novel application of the Generalized Inverse Infection Model (GIIM). The GIIM model uses real observations from the outbreak and seeks to estimate the risk factors driving transmission. The observations are derived from the dates of reported local transmission of Zika virus in each region, the network structure is defined by the passenger air travel movements between all pairs of regions, and the risk factors considered include regional socioeconomic factors, vector habitat suitability, travel volumes, and epidemiological data. The GIIM relies on a multi-agent based optimization method to estimate the parameters, and utilizes a data driven stochastic-dynamic epidemic model for evaluation. As expected, we found that mosquito abundance, incidence rate at the origin region, and human population density are risk factors for Zika virus transmission and spread. Surprisingly, air passenger volume was less impactful, and the most significant factor was (a negative relationship with) the regional gross domestic product (GDP) per capita.
Conclusions/significance: Our model generates country level exportation and importation risk profiles over the course of the epidemic and provides quantitative estimates for the likelihood of introduced Zika virus resulting in local transmission, between all origin-destination travel pairs in the Americas. Our findings indicate that local vector control, rather than travel restrictions, will be more effective at reducing the risks of Zika virus transmission and establishment. Moreover, the inverse relationship between Zika virus transmission and GDP suggests that Zika cases are more likely to occur in regions where people cannot afford to protect themselves from mosquitoes. The modeling framework is not specific for Zika virus, and could easily be employed for other vector-borne pathogens with sufficient epidemiological and entomological data.
Conflict of interest statement
The authors have declared that no competing interests exist.
Figures
Similar articles
-
A dynamic neural network model for predicting risk of Zika in real time.BMC Med. 2019 Sep 2;17(1):171. doi: 10.1186/s12916-019-1389-3. BMC Med. 2019. PMID: 31474220 Free PMC article.
-
Elevation as a proxy for mosquito-borne Zika virus transmission in the Americas.PLoS One. 2017 May 24;12(5):e0178211. doi: 10.1371/journal.pone.0178211. eCollection 2017. PLoS One. 2017. PMID: 28542540 Free PMC article.
-
Potential for Zika Virus to Establish a Sylvatic Transmission Cycle in the Americas.PLoS Negl Trop Dis. 2016 Dec 15;10(12):e0005055. doi: 10.1371/journal.pntd.0005055. eCollection 2016 Dec. PLoS Negl Trop Dis. 2016. PMID: 27977671 Free PMC article. Review.
-
Potential for Zika virus introduction and transmission in resource-limited countries in Africa and the Asia-Pacific region: a modelling study.Lancet Infect Dis. 2016 Nov;16(11):1237-1245. doi: 10.1016/S1473-3099(16)30270-5. Epub 2016 Sep 1. Lancet Infect Dis. 2016. PMID: 27593584 Free PMC article.
-
The Convergence of a Virus, Mosquitoes, and Human Travel in Globalizing the Zika Epidemic.J Community Health. 2016 Jun;41(3):674-9. doi: 10.1007/s10900-016-0177-7. J Community Health. 2016. PMID: 26969497 Review.
Cited by
-
High-Risk Areas for Congenital Zika Syndrome in Rio de Janeiro: Spatial Cluster Detection.Trop Med Infect Dis. 2024 May 7;9(5):105. doi: 10.3390/tropicalmed9050105. Trop Med Infect Dis. 2024. PMID: 38787038 Free PMC article.
-
Cryptic Zika virus infections unmasked from suspected malaria cases in Northeastern Nigeria.PLoS One. 2023 Nov 8;18(11):e0292350. doi: 10.1371/journal.pone.0292350. eCollection 2023. PLoS One. 2023. PMID: 37939049 Free PMC article.
-
A systematic review of the data, methods and environmental covariates used to map Aedes-borne arbovirus transmission risk.BMC Infect Dis. 2023 Oct 20;23(1):708. doi: 10.1186/s12879-023-08717-8. BMC Infect Dis. 2023. PMID: 37864153 Free PMC article.
-
Antibody seropositivity and endemicity of chikungunya and Zika viruses in Nigeria.Anim Dis. 2023;3(1):7. doi: 10.1186/s44149-023-00070-2. Epub 2023 Mar 23. Anim Dis. 2023. PMID: 36968287 Free PMC article.
-
Sociodemographic and environmental factors associated with dengue, Zika, and chikungunya among adolescents from two Brazilian capitals.PLoS Negl Trop Dis. 2023 Mar 16;17(3):e0011197. doi: 10.1371/journal.pntd.0011197. eCollection 2023 Mar. PLoS Negl Trop Dis. 2023. PMID: 36928657 Free PMC article.
References
-
- Ioos S, Mallet HP, Leparc Goffart I, Gauthier V, Cardoso T, Herida M. Current Zika virus epidemiology and recent epidemics [Journal Article]. Medecine et Maladies Infectieuses. 2014;44(7):302–307. Available from: http://www.scopus.com/inward/record.url?eid=2-s2.0-84905560476&partnerID... http://ac.els-cdn.com/S0399077X14001085/1-s2.0-S0399077X14001085-main.pd.... 10.1016/j.medmal.2014.04.008 - DOI - PubMed
-
- Faria N, Azevedo R, Kraemer M, Souza R, Cunha M, Hill S, et al. Zika virus in the Americas: Early epidemiological and genetic findings. Science. 2016;Available from: http://science.sciencemag.org/content/early/2016/03/23/science.aaf5036. - PMC - PubMed
-
- PAHO. Regional Zika Epidemiological Update (Americas) May 25, 2017 [Web Page]. Washington DC: World Health Organization, Pan American Health Organization; 2017. Available from: http://www.paho.org/hq/index.php?option=com_content&id=11599&Itemid=41691.
Publication types
MeSH terms
Grants and funding
LinkOut - more resources
Full Text Sources
Other Literature Sources
Medical
Research Materials