Genetic characterization of West Nile Virus strains during neuroinvasives infection outbreak in Tunisia, 2018
TRANSBOUNDARY AND EMERGING DISEASES
Authors: Fares, Wasfi; Gdoura, Mariem; Dhrif, Haifa; Touzi, Henda; Hogga, Nahed; Hannachi, Naila; Mhalla, Salma; Kacem, Saoussen; Karray, Hela; Bougatef, Souha; Ben-Alaya, Nissaf; Triki, Henda
Abstract
West Nile Virus (WNV) is an arbovirus transmitted by mosquito bite involving birds as reservoirs, humans and equines as accidental hosts. Eight distinct lineages (WNV-1 to WNV-8) have been identified: WNV-1 and WNV-2 infect humans and animals, and WNV-3 to WNV-8 have been identified only in vectors. WNV has been implicated in neuroinvasives infections, especially meningitis and encephalitis. Tunisia experienced three epidemics in 1997, 2003 and 2012. Serological studies on humans, equines and birds as well as the detection of the virus in the vector favour a fairly frequent circulation in the country. A new epidemic has been observed in Tunisia between August and November 2018. The obtained sequences of the VWN from Tunisia 2018 grouped in a distinct monophyletic group within the Mediterranean subtype in Cluster 1, with a maximum of 2% nucleotide divergence. These sequences were clearly distinct from the Tunisia 1997, which grouped with sequences mainly from USA in Cluster 2. This work reports the genetic characterization of the Tunisia 2018 strain in comparison with the previously identified strains in Tunisia and worldwide. The epidemic virus Tunisia 2018 was genetically close to the Mediterranean basin and Eastern Europe sequences but distinct from the Tunisia 1997 closely related to the American sequences.
Sinus Bradycardia and QT Interval Prolongation in West Nile Virus Encephalitis: A Case Report
CUREUS
Authors: Ajam, Mustafa; Abu-Heija, Ahmad A.; Shokr, Mohamed; Ajam, Firas; Saydain, Ghulam
Abstract
Cardiac arrhythmias were reported in cases of West Nile Virus (WNV) encephalitis; however, the underlying pathophysiology remains incompletely understood. We present a 67-year-old male with altered mental status, later diagnosed with WNV encephalitis. Hospital course was complicated by progressive sinus bradycardia and corrected QT (QTc) prolongation. These findings persisted despite the absence of classical causes and resolved only after improvement of the underlying encephalitis. After excluding classical causes, autonomic dysfunction is one of the proposed mechanisms behind cardiac arrhythmias in WNV encephalitis. Resolution of arrhythmias is expected after the improvement of underlying encephalitis and should be taken into consideration before proceeding for pacemaker placement or other cardiac intervention. Furthermore, this case highlights the importance of continuous cardiac monitoring in WNV encephalitis patients.