Tag: surveillance

Mapping the Global Overlap of Four Major Mosquito-Borne Viruses

As arbovirus outbreaks continue to surge globally, a new study sheds light on the overlapping environmental risks for dengue, Zika, chikungunya, and yellow fever—all transmitted primarily by Aedes aegypti and Aedes albopictus mosquitoes. Among the contributing authors is Moritz Kramer, a researcher at the University of Oxford and a key member of the E4Warning project. The study is a result of international collaboration between leading institutions, including Oxford, the London School of Hygiene & Tropical Medicine, the University of Melbourne, the Boston Children’s Hospital, University of Washington University of Cambridge, Nagasaki University, niversity of Florida, the World Health Organization, and the Harvard Medical School.

 In this large-scale study, researchers compiled over 21,000 occurrence records and developed the most comprehensive global environmental suitability maps to date, using a joint ecological niche modelling approach. What makes this work stand out is its integration of multiple diseases, correcting for long-standing biases in surveillance data, and providing a common suitability framework for all four diseases.

 Key findings include:

  • An estimated 5.66 billion people live in areas suitable for dengue, Zika, and chikungunya—around 73% of the global population.

  • 1.54 billion people live in areas suitable for yellow fever transmission.

  • The study reveals high overlap in suitable areas for dengue, Zika, and chikungunya, indicating that any region reporting one of these diseases could be at risk of the others.

  • Risk maps show new potential hotspots in areas like West and Central Africa, southern Europe, and parts of Asia, where surveillance is low or diseases are underreported.

  • Models highlight that underreporting and limited diagnostic capacity in low-income countries may skew perceived disease distribution, underlining the importance of adjusting for surveillance capability in global risk mapping.

 

The global number of new unique occurrence points added each year (i.e., after thinning). Years with sparse (n < 100) occurrence records (1927–1984) are not shown. b–e global maps of occurrence data for dengue (b), chikungunya (c), Zika (d), and yellow fever (e).
Model-predicted relative surveillance capability for emerging acute viral infectious diseases. Values close to 1 (yellow) indicate that a viral infection is more likely to be publicly reported.

 

By using a two-stage modelling strategy—one for disease risk and one for surveillance capacity—the researchers produce more accurate and actionable risk assessments, offering a better foundation for targeted disease surveillance, early warning, and response systems.  The results emphasize the need for integrated arbovirus monitoring and the value of cross-disease models in a world of expanding ecological and climate pressures.

Read the full open access here: https://doi.org/10.1038/s41467-025-58609-5

Lim, A., Shearer, F. M., Sewalk, K., Pigott, D. M., Clarke, J., Ghouse, A., Judge, C., Kang, H., Messina, J. P., Kraemer, M. U. G., Gaythorpe, K. A. M., de Souza, W. M., Nsoesie, E. O., Celone, M., Faria, N., Ryan, S. J., Rabe, I. B., Rojas, D. P., Hay, S. I., Brownstein, J. S., Golding, N., & Brady, O. J. 2025. The overlapping global distribution of dengue, chikungunya, Zika and yellow fever. Nature Communications, 16, 3418. https://doi.org/10.1038/s41467-025-58609-5

And in the E4Warning Zenodo repository: https://zenodo.org/records/15223772

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