The Potential Distance of Highly Pathogenic Avian Influenza Virus Dispersal by Mallard, Common Teal and Eurasian Pochard

Abstract

Waterbirds represent the major natural reservoir for low pathogenic (LP) avian influenza viruses (AIV). Among the wide diversity of subtypes that have been described, two of them (H5 and H7) may become highly pathogenic (HP) after their introduction into domestic bird populations and cause severe outbreaks, as is the case for HP H5N1 in South-Eastern Asia. Recent experimental studies demonstrated that HP H5N1 AIV infection in ducks does not necessarily have significant pathological effects. These results suggest that wild migratory ducks may asymptomatically carry HP AIV and potentially spread viruses over large geographical distances. In this study, we investigated the potential spreading distance of HP AIV by common teal (Anas crecca), mallard (A. platyrhynchos), and Eurasian pochard (Aythya ferina). Based on capture-mark-recapture method, we characterized their wintering movements from a western Mediterranean wetland (Camargue, South of France) and identified the potential distance and direction of virus dispersal. Such data may be crucial in determining higher-risk areas in the case of HP AIV infection detection in this major wintering quarter, and may serve as a valuable reference for virus outbreaks elsewhere.

Ecological Modeling of the Spatial Distribution of Wild Waterbirds to Identify the Main Areas Where Avian Influenza Viruses are Circulating in the Inner Niger Delta, Mali

“…One consequently must turn to knowledge-based approaches combining environmental and socioeconomical data to derive predictions (Smith et al, 2005). These approaches then can be used to determine high-risk areas (Cumming et al, 2008;Brochet et al, 2009), prioritize surveillance programs, and plan interventions (Clements and Pfeiffer, 2009).…”

Disease Dynamics and Bird Migration—Linking Mallards Anas platyrhynchos and Subtype Diversity of the Influenza A Virus in Time and Space

“…Data from waterfowl migration (counts, band recoveries, transmitters, loggers etc.) and geographic information have been used to model the capacity of waterfowl to transmit HPAI virus through migration [3], [22]–[25]. Such data could also be used to identify areas of higher risk for HPAI and point out relevant sites for influenza A surveillance.…”

Spring migratory routes and stopover duration of satellite‐tracked Eurasian Teals Anas crecca wintering in Italy

“…Given that ring‐recoveries have shown that during the wintering period Teals can move for > 30 km within a relatively short time period (< 30 days; Brochet et al . ), the estimated starting date used in this paper might underestimate the actual timing of spring migration, as it may refer to late wintering movements not related to migration. We assumed that a Teal completed its spring migration (CM Teal hereafter, n = 15) if: (1) it stopped in the same delimited area, moving very short distances between successive locations (< 4 km), for more than 1 month between the end of April and June (see Guillemain & Elmberg ) or (2) its last locations were recorded during the breeding season (after the end of April) and in a plausible breeding area (see Guillemain & Elmberg ), in case the PTT stopped transmitting before the end of June.…”