Evidence of West Nile virus circulation among humans in central northern Algeria

Abstract

West Nile Virus (WNV) is the most widely distributed flavivirus worldwide. It is a mosquito-borne virus, and birds constitute its natural reservoir. Humans and equines are considered accidental hosts. Human WNV infections are usually asymptomatic or express as a mild febrile syndrome; however, in around 1% of cases they are responsible for more serious neurological diseases with a potentially lethal outcome. In the Mediterranean basin the virus circulation is regarded as endemic. Outbreaks of WNV meningoencephalitis are regularly notified, especially during summer and autumn seasons. In Algeria, although some surveys have reported WNV activity in the Sahara, to date few data are available about virus circulation in the northern part of the country. We conducted this study to detect possible WNV activity in this part of Algeria. For this purpose, in 2010 a total of 164 human sera were collected from native patients of the Algiers district and surrounding areas, then tested retrospectively for IgG anti-WNV by ELISA. Plaque reduction neutralization technique (PRNT) was used for result confirmation. In this cohort, 9.8% of the 164 collected sera returned positive for anti-WNV IgG; after confirmation by PRNT; 6.7% had specific neutralizing antibodies. No statistically significant difference was observed according to the sex or transfusion status of the patients. In conclusion, these data show for the first time serological evidence of WNV circulation in Algiers and its surrounding areas. They also highlight the need for implementing an integrated surveillance programme covering all aspects of WNV disease in order to better understand the circulation dynamics of WNV in this region. Other flaviviruses antigenically related to WNV should be investigated, given the evidence of serological cross-reaction, as specific IgG antibodies decrease after PRNT confirmation.

Seroprevalence of West Nile Virus in Regular Blood Donors Referred to the Blood Bank of Kurdistan Province, Iran

“…Concerning the prevalence of WNV IgG antibody, the results of the present study are in line with many studies conducted in other countries, especially in the Middle East and other parts of the world such as Libya, Algeria, Northern Cyprus, Bolivia, Hungary, Greece and Jordan, as well as in studies carried out in Iran, in which the prevalence of the aforementioned antibody ranged from 2.34% to 8.61% [5,[17][18][19][20][21][22][23][24][25].…”

An Assessment of West Nile and Usutu Viruses’ Seroprevalence in Hospitalized Patients: A Preliminary Study on Flavivirus Exposure in Eastern Romania

“…The WNV IgG seroprevalence determined from the 176 samples analyzed is similar to one found in Italy (3.7%) in 2507 individuals [22] and in Tunisia (4.3%) in 742 patients in 2003 [23], but lower than that in Algeria (9.8%) [24], Zambia (10.3%) [25], and Gabon (27.2%) [26]. In Romania, a previous study performed among asymptomatic blood donors in the north-western region of Romania showed an overall seroprevalence of 3.2% in a cohort of 1200 participants [16].…”

Mosquito Vectors (Diptera: Culicidae) and Mosquito-Borne Diseases in North Africa

“…Hachid et al conducted a retrospective study targeting human sera collected in Algiers and the surrounding provinces. This work underlined the fact that 9.8% of the 164 collected sera had IgG against WNV, which was confirmed for the 6.7% of them harboring specific neutralizing antibodies [ 154 ].…”