Epidemics of the central nervous system infections caused by West Nile virus in the territory of the South Bačka District, Vojvodina, Serbia

Siniša Đ Sević; Sandra Stefan-Mikić; Dragana Šipovac; Vesna Turkulov; Vesna Milošević; Ivana Hrnjaković-Cvjetković

doi:10.2298/6474

Siniša Đ Sević Clinic for Infectious Diseases, Clinical Center of Vojvodina, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
Sandra Stefan-Mikić Clinic for Infectious Diseases, Clinical Center of Vojvodina, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
Dragana Šipovac Health Care Center “Novi Sad”, Novi Sad, Serbia
Vesna Turkulov Institute for Public Health of Vojvodina, Clinical Center of Vojvodina, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
Vesna Milošević Institute for Public Health of Vojvodina, Clinical Center of Vojvodina, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
Ivana Hrnjaković-Cvjetković Institute for Public Health of Vojvodina, Clinical Center of Vojvodina, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia

DOI: https://doi.org/10.2298/6474

Abstract

Background/Aim. West Nile virus (WNV) is a neurotropic RNA virus particle which belongs to the Flaviviridae family, genus Flavivirus. It is sustained in arthropods within the transmission cycle between the mosquitoes and birds. Most commonly (80% of cases) WNV infections are asymptomatic among people. Less than 1% of patients develop neuroinvasive forms of the disease – meningitis, encephalitis, or acute flaccid paralysis. The aim of the research was to determine most common clinical and laboratory manifestations, to emphazise the presence of comorbidities and outcomes of treatment among patients with WNV infection. Methods. This retrospective study, which was conducted in the period from January 1, 2012 to December 31, 2013, evaluated 32 patients who were diagnosed with WNV infection based on clinical findings, laboratory, and serological tests. To assess statistical significance we used χ², and t-test. Results. The study involved 22 (69%) males and 10 (31%) females aged from 31 to 65 years. On admission, there were 16 (50%) febrile individuals, 27 (84.4%) with positive meningeal signs, 17 (53.2%) with pathological neurological signs, and 10 (31.3%) with consciousness disorders. WNV infection was confirmed by the method enzyme linked immuno sorbent assay (ELISA) in all the patients, while Reverse Transcription Polymerase Chain Reaction (RT-PCR) test was positive in 3 (30%) of the tested patients. Cardiovascular comorbidities dominated in 7 (21.9%) of the cases. Full recovery was accomplished in 87.5 % of the cases. Conclusion. The results of our study show that the absence of meningeal signs and fever on the day 7 of hospital treatment are indicators of good course and prognosis of neuroinvasive forms of WNV infection. Comorbidities do not increase the risk of disease. ELISA test is a sovereign diagnostic method. In most cases, after the administered symptomatic therapy, the complete recovery of patients was achieved.

Key words:

west nile virus; central nervous system viral diseases; diagnosis; treatment outcome; prognosis; serbia.

Author Biography

Siniša Đ Sević, Clinic for Infectious Diseases, Clinical Center of Vojvodina, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia

Vanredni profesor Medicinskog fakulteta, Univerziteta u Novom Sadu; Šef katedre za gerijatriju; Šef odseka za lečenje centralnog nervnog sistema Klinike za infektivne bolesti, Kliničkog centra Vojvodine.

References

Crowder DW, Dykstra EA, Brauner JM, Duffy A, Reed C, Martin E, et al. West Nile Virus Prevalence across Landscapes Is Me-diated by Local Effects of Agriculture on Vector and Host Communities. PLoS ONE 2013; 8(1): e55006.

Faggioni G, Pomponi A, de Santis R, Masuelli L, Ciammaruconi A, Monaco F, et al. West Nile alternative open reading frame (N-NS4B/WARF4) is produced in infected West Nile Virus (WNV) cells and induces humoral response in WNV infected individuals. Virol J 2012; 9: 283.

Popović N, Milošević B, Urošević A, Poluga J, Lavadinović L, Nedelijković J, et al. Outbreak of West Nile virus infection among humans in Serbia, August to October 2012. Euro Surveill 2013; 18(43): pii: 20613.4.

Schultze-Amberger J, Emmerich P, Günther S, Schmidt-Chanasit J. West Nile virus meningoencephalitis imported into Germany. Emerg Infect Dis 2012; 18(10): 1698−700.

Nett RJ, Kuehnert MJ, Ison MG, Orlowski JP, Fischer M, Staples JE. Current practices and evaluation of screening solid organ donors for West Nile virus. Transpl Infect Dis 2012; 14(3): 268−77.

Hrnjaković-Cvjetković I, Cvjetković D, Petrić D, Milošević V, Jerant-Patić V, Zgomba M. Up-To Date Knowledge of West Nile Vi-rus Infection. Med Pregl 2009; 62(5−6): 231−5. (Serbian)

Petrović T, Blázquez AB, Lupulović D, Lazić G, Escribano-Romero E, Fabijan D, et al. Monitoring West Nile virus (WNV) infec-tion in wild birds in Serbia during 2012: first isolation and characterisation of WNV strains from Serbia. Euro Surveill 2013; 18(44): 1−8.

Sanchini A, Donoso-Mantke O, Papa A, Sambri V, Teichmann A. Second International Diagnostic Accuracy Study for the Sero-logical Detection of West Nile Virus Infection. PLoS Negl Trop Dis 2013; 7(4): e2184.

Cnops L, Papa A, Lagra F, Weyers P, Meersman K, Patsouros N, et al. West Nile virus infection in Belgian traveler returning from Greece. Emerging Infect Dis 2013; 19(4): 684−5.

Kelly S, Brown JA, Lawaczek EW, Kuehnert M, Rabe I, Staples JE, et al. Fatal West Nile virus infection after probable transfu-sion-associated transmission-Colorado, 2012. MMWR Morb Mortal Wkly Rep 2013; 62(31): 622−4.

Lupulovic D, Martín-Acebes MA, Lazic S, Alonso-Padilla J, Bláz-quez A, Escribano-Romero E, et al. First serological evidence of West Nile virus activity in horses in Serbia. Vector Borne Zoonotic Dis 2011; 11(9): 1303−5.

Ciota AT, Ehrbar DJ, Matacchiero AC, van Slyke GA, Kramer LD. The evolution of virulence of West Nile virus in a mosquito vector: implications for arbovirus adaptation and evolution. BMC Evol Biol 2013; 13: 71.

Brown CM, de Maria A. The resurgence of West Nile virus. Ann Intern Med 2012; 157(11): 823−4.

Aleksić I, Jevremović J, Pešić B. Detection of the West Nile Fever Virus in the Mosquito Population in the Territory of the Republic of Serbia. Belgrade: Institute for Biocides and Medical Ecology; 2013. (Serbian)

Lindsey NP, Lehman JA, Staples JE, Fischer M. West Nile virus and other arboviral diseases-United States, 2012. MMWR Morb Mortal Wkly Rep 2013; 62(25): 513−7.

Huang ZYX, de Boer WF, van Langevelde F, Olson V, Blackburn TM, Prins HH, et al. Species' Life-History Traits Explain In-terspecific Variation in Reservoir Competence: A Possible Mechanism Underlying the Dilution Effect. PLoS ONE 2013; 8(1): 10.

Smailagic J, Savovic A, Nesic D, Milenkovic M, Zdravkovic S. Climatological analysis of summer 2012 for Serbia. 2012. Available from: http://www.hidmet.gov.rs/podaci/meteorologija/eng/l2012.pdf

Nasci RS. Monitoring and Controlling West Nile Virus: Are Your Prevention Practices in Place? J Environ Health 2013; 75(8): 42−4.

Chaintoutis SC, Chaskopoulou A, Chassalevris T, Koehler PG, Papanastassopoulou M, Dovas CI. West Nile virus lineage 2 strain in Greece, 2012. Emerg Infect Dis 2013; 19(5): 827−9.

Kwan JL, Park BK, Carpenter TE, Ngo V, Civen R, Reisen WK. Comparison of enzootic risk measures for predicting West Nile disease, Los Angeles, California, USA, 2004-2010. Emerg Infect Dis 2012; 18(8): 1298−306.

Nolan MS, Schuermann J, Murray KO. West Nile virus infection among humans, Texas, USA, 2002-2011. Emerg Infect Dis 2013; 19(1): 137−9.

Zaayman D, Venter M. West Nile virus neurologic disease in humans, South Africa, September 2008-may 2009. Emerg In-fect Dis 2012; 18(12): 2051−4.

Aslan M, Kocazeybek B, Turan N, Karakose AR, Altan E, Yuksel P, et al. Investigation of schizophrenic patients from Istanbul, Turkey for the presence of West Nile virus. Eur Arch Psychia-try Clin Neurosci 2012; 262(2): 173−7.

García-Bocanegra I, Jaén-Téllez JA, Napp S, Arenas-Montes A, Fernández-Morente M, Fernández-Molera V, et al. Monitoring of the West Nile virus epidemic in Spain between 2010 and 2011. Transbound Emerg Dis 2012; 59(5): 448−55.

Ibarra-Juarez L, Eisen L, Bolling BG, Beaty BJ, Blitvich BJ, Sanchez-Casas RM, et al. Detection of West Nile virus-specific antibodies and nucleic acid in horses and mosquitoes, respectively, in Nuevo Leon State, northern Mexico, 2006-2007. Med Vet Entomol 2012; 26(3): 351−4.

Rappole JH, Derrickson SR, Hubálek Z. Migratory birds and spread of West Nile virus in the Western Hemisphere. Emerg Infect Dis 2000; 6(4): 319−28.

Valiakos G, Touloudi A, Athanasiou LV, Giannakopoulos A, Iaco-vakis C, Birtsas P, et al. Serological and molecular investigation into the role of wild birds in the epidemiology of West Nile virus in Greece. Virol J 2012; 9: 266.

Hamer SA, Lehrer E, Magle SB. Wild birds as sentinels for multiple zoonotic pathogens along an urban to rural gradient in greater Chicago, Illinois. Zoonoses Public Health 2012; 59(5): 355−64.

Santisteban L, Benkman CW, Fetz T, Smith JW. Survival and population size of a resident bird species are declining as tem-perature increases. J Anim Ecol 2012; 81(2): 352−63.