A fatal neuroinvasive West Nile virus infection in a traveler returning from Madagascar: clinical, epidemiological and veterinary investigations

Sophie Larrieu (1) , Eric Cardinale (2, 3, 4) , Philippe Ocquidant (5) , Matthieu Roger (3, 2, 4) , Richard Lepec (6) , Hélène Delatte (7) , Guillaume Camuset (5) , Philippe Desprès (8) , Elise Brottet (1) , Cyril Charlin (5) , Alain Michault (9, 5)

1 CIRE Océan Indien - Cellule interrégionale d'épidémiologie Océan Indien [Saint-Denis, La Réunion]
2 CRVOI - Centre de Recherche et de Veille sur les Maladies Émergentes dans l'Océan Indien
3 UMR CMAEE - Contrôle des maladies animales exotiques et émergentes
4 Cirad-BIOS - Département Systèmes Biologiques
5 CHU Sud Saint Pierre [Ile de la Réunion]
6 COI - Commission de l'Océan Indien
7 MIVEGEC - Maladies infectieuses et vecteurs : écologie, génétique, évolution et contrôle
8 Centre national de Référence et Centre Collaborateur de l'OMS Arbovirus (CNR-CCOMS)
9 Laboratoire de Bactériologie-Parasitologie-Virologie-Hygiène

A 58-year-old woman living in Reunion Island and returning from Madagascar was hospitalized for neuroinvasive encephalitis and died 1 month later. West Nile virus (WNV) infection was biologically confirmed by detection of immunoglobulin M (IgM) reactive with WNV antigens in both cerebrospinal fluid and serum, and weak neutralizing activity was also detected. A veterinary survey performed in her traveling area showed a seroprevalence ofWNV of 28.7% (95% confidence interval [CI]=21.1–36.3) in adult poultry, confirming an active circulation of the virus.Development of a severe form could be related to a weak antibody response, because the patient presented low IgM and IgG titers. This case report underlines the constant risk of emergence of West Nile in Indian Ocean territories, including Reunion Island where competent vectors are widely present during the whole year.

Domaines: Sciences du Vivant [q-bio]

Sophie Larrieu, Eric Cardinale, Philippe Ocquidant, Matthieu Roger, Richard Lepec, et al.. A fatal neuroinvasive West Nile virus infection in a traveler returning from Madagascar: clinical, epidemiological and veterinary investigations. American Journal of Tropical Medicine and Hygiene, 2013, 89 (2), pp.211--213. ⟨10.4269/ajtmh.12-0003⟩. ⟨hal-01274588⟩