Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 May;26(19):2002010.
doi: 10.2807/1560-7917.ES.2021.26.19.2002010.

Unprecedented increase of West Nile virus neuroinvasive disease, Spain, summer 2020

Lucía García San Miguel Rodríguez-Alarcón  1 , Beatriz Fernández-Martínez  2   3 , María José Sierra Moros  1 , Ana Vázquez  3   4 , Paula Julián Pachés  5 , Elena García Villacieros  6 , María Belén Gómez Martín  6 , Jordi Figuerola Borras  3   7 , Nicola Lorusso  8 , Julian Mauro Ramos Aceitero  9 , Elena Moro  10 , Aránzazu de Celis  10 , Salvador Oyonarte  10 , Beatriz Mahillo  11 , Luis José Romero González  6 , María Paz Sánchez-Seco  4 , Berta Suárez Rodríguez  1 , Ulises Ameyugo Catalán  12 , Santiago Ruiz Contreras  13 , Mayte Pérez-Olmeda  4 , Fernando Simón Soria  1
Affiliations

Unprecedented increase of West Nile virus neuroinvasive disease, Spain, summer 2020

Lucía García San Miguel Rodríguez-Alarcón et al. Euro Surveill. 2021 May.

Abstract

Cases of West Nile neuroinvasive disease (WNND) in Spain increased in summer 2020. Here we report on this increase and the local, regional and national public health measures taken in response. We analysed data from regional surveillance networks and the National Epidemiological Surveillance Network, both for human and animal West Nile virus (WNV) infection. During the 2020 season, a total of 77 human cases of WNV infection (median age 65 years; 60% males) were detected in the south-west of Spain; 72 (94%) of these cases developed WNND, presenting as meningoencephalitis, seven of which were fatal. In the previous two decades, only six human cases of WNND were detected in Spain. Reduced activities for vector control this season, together with other factors, might have contributed to the massive increase. Public health measures including vector control, campaigns to raise awareness among physicians and the general population, and interventions to ensure the safety of donations of blood products, organs, cells and tissues were effective to reduce transmission. Going forward, maintenance of vector control activities and an update of the vector-borne diseases response plan in Spain is needed.

Keywords: Spain; WNV; West Nile fever; West Nile virus; epidemiology; surveillance; vector-borne infections; viral infections.

PubMed Disclaimer

Conflict of interest statement

Conflict of interest: None declared.

Figures

Figure 1
Figure 1
Epidemic curve of confirmed and probable human cases of West Nile virus infection, by province, Spain, as at 30 November 2020 (n=77)
Figure 2
Figure 2
Equid outbreaks and human cases of West Nile virus (WNV) infection by region and WNV lineage 2 detection in wild birds, Spain 2010–2020
Figure 3
Figure 3
Distribution of confirmed and probable human West Nile virus cases, by age and sex, Spain, 2020 (n = 77)
See this image and copyright information in PMC

References

    1. Patel H, Sander B, Nelder MP. Long-term sequelae of West Nile virus-related illness: a systematic review. Lancet Infect Dis. 2015;15(8):951-9. - PubMed
    1. Petersen LR, Brault AC, Nasci RS. West Nile Virus: Review of the Literature. JAMA. 2013;310(3):308-15. - PMC - PubMed
    1. Bakonyi T, Ferenczi E, Erdélyi K, Kutasi O, Csörgő T, Seidel B, et al. Explosive spread of a neuroinvasive lineage 2 West Nile virus in Central Europe, 2008/2009. Vet Microbiol. 2013;165(1-2):61-70. - PubMed
    1. Papa A, Bakonyi T, Xanthopoulou K, Vázquez A, Tenorio A, Nowotny N. Genetic characterization of West Nile virus lineage 2, Greece, 2010. Emerg Infect Dis. 2011;17(5):920-2. - PMC - PubMed
    1. Chancey C, Grinev A, Volkova E, Rios M. The Global Ecology and Epidemiology of West Nile Virus. BioMed Res Int. 2015;2015:376230. - PMC - PubMed