Limits...
Diagnostic approach for monitoring hydroclimatic conditions related to emergence of west nile virus in west virginia.

Jutla A, Huq A, Colwell RR - Front Public Health (2015)

Bottom Line: Analysis of land surface temperature (LST) pattern shows that temperature values >16°C, with heavy precipitation, may lead to abundance of the mosquito population.This hypothesis was tested in West Virginia where a sudden epidemic of WNV infection was reported in 2012.Our results emphasize the value of hydroclimatic processes estimated by satellite remote sensing, as well as continued environmental surveillance of mosquitoes, because when a vector-borne infection like WNV is discovered in contiguous regions, the risk of spread of WNV mosquitoes increase at points where appropriate hydroclimatic processes intersect with the vector niche.

View Article: PubMed Central - PubMed

Affiliation: Department of Civil and Environmental Engineering, West Virginia University , Morgantown, WV , USA.

ABSTRACT
West Nile virus (WNV), mosquito-borne and water-based disease, is increasingly a global threat to public health. Since its appearance in the northeastern United States in 1999, WNV has since been reported in several states in the continental United States. The objective of this study is to highlight role of hydroclimatic processes estimated through satellite sensors in capturing conditions for emergence of the vectors in historically disease free regions. We tested the hypothesis that an increase in surface temperature, in combination with intensification of vegetation, and enhanced precipitation, lead to conditions favorable for vector (mosquito) growth. Analysis of land surface temperature (LST) pattern shows that temperature values >16°C, with heavy precipitation, may lead to abundance of the mosquito population. This hypothesis was tested in West Virginia where a sudden epidemic of WNV infection was reported in 2012. Our results emphasize the value of hydroclimatic processes estimated by satellite remote sensing, as well as continued environmental surveillance of mosquitoes, because when a vector-borne infection like WNV is discovered in contiguous regions, the risk of spread of WNV mosquitoes increase at points where appropriate hydroclimatic processes intersect with the vector niche.

No MeSH data available.


Related in: MedlinePlus

Percentage change in NDVI in July 2012 with respect to July 2011. The inset numbers on map are the WNV positive mosquitoes in year 2012 in counties of West Virginia. (Black box in the figure – 38.6825°N to 37.8788°N; 82.5844°W to 81.0955°; and include Cabell and Kanawha counties of West Virginia).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4325936&req=5

Figure 4: Percentage change in NDVI in July 2012 with respect to July 2011. The inset numbers on map are the WNV positive mosquitoes in year 2012 in counties of West Virginia. (Black box in the figure – 38.6825°N to 37.8788°N; 82.5844°W to 81.0955°; and include Cabell and Kanawha counties of West Virginia).

Mentions: Increase in LST may not be sufficient to explain the expansion of mosquitoes throughout the region. Mosquitoes prefer a humid environment that often occurs in areas of high vegetation, since such areas store more volumetric water in the vadoze zone that is easily accessible, maintaining higher humidity. To assess the effects of vegetation, we used a 16-day NDVI product from the MODIS Terra platform. Percentage difference in NDVI values between July 2012 and 2011 were computed, with the premise that NDVI values should be higher in 2012 than during the preceding year. Figure 4 shows an average increase of 4.5% in NDVI, marked by the black box, where high prevalence of WNV positive mosquitoes was observed in 2012 (average NDVI 0.89). However, high values (NDVI > 0.89) of NDVI indicates that the region is already saturated with vegetation, which it covers part of Appalachian forests. Precipitation was above average for July 2012 (Figure 5A) and below average for 2011 (Figure 5B). Rainfall in July 2012 was 6″ above normal (black box) compared to July 2011, with 2″ less than normal precipitation, which may be a contributing factor to the increase in the NDVI in July 2012 and substantiating the hypothesis that increased temperature and followed by precipitation are associated with increase in mosquito population, namely Cx. pipiens/restuans, the primary WNV vector in the eastern United States (12, 14, 15).


Diagnostic approach for monitoring hydroclimatic conditions related to emergence of west nile virus in west virginia.

Jutla A, Huq A, Colwell RR - Front Public Health (2015)

Percentage change in NDVI in July 2012 with respect to July 2011. The inset numbers on map are the WNV positive mosquitoes in year 2012 in counties of West Virginia. (Black box in the figure – 38.6825°N to 37.8788°N; 82.5844°W to 81.0955°; and include Cabell and Kanawha counties of West Virginia).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4325936&req=5

Figure 4: Percentage change in NDVI in July 2012 with respect to July 2011. The inset numbers on map are the WNV positive mosquitoes in year 2012 in counties of West Virginia. (Black box in the figure – 38.6825°N to 37.8788°N; 82.5844°W to 81.0955°; and include Cabell and Kanawha counties of West Virginia).
Mentions: Increase in LST may not be sufficient to explain the expansion of mosquitoes throughout the region. Mosquitoes prefer a humid environment that often occurs in areas of high vegetation, since such areas store more volumetric water in the vadoze zone that is easily accessible, maintaining higher humidity. To assess the effects of vegetation, we used a 16-day NDVI product from the MODIS Terra platform. Percentage difference in NDVI values between July 2012 and 2011 were computed, with the premise that NDVI values should be higher in 2012 than during the preceding year. Figure 4 shows an average increase of 4.5% in NDVI, marked by the black box, where high prevalence of WNV positive mosquitoes was observed in 2012 (average NDVI 0.89). However, high values (NDVI > 0.89) of NDVI indicates that the region is already saturated with vegetation, which it covers part of Appalachian forests. Precipitation was above average for July 2012 (Figure 5A) and below average for 2011 (Figure 5B). Rainfall in July 2012 was 6″ above normal (black box) compared to July 2011, with 2″ less than normal precipitation, which may be a contributing factor to the increase in the NDVI in July 2012 and substantiating the hypothesis that increased temperature and followed by precipitation are associated with increase in mosquito population, namely Cx. pipiens/restuans, the primary WNV vector in the eastern United States (12, 14, 15).

Bottom Line: Analysis of land surface temperature (LST) pattern shows that temperature values >16°C, with heavy precipitation, may lead to abundance of the mosquito population.This hypothesis was tested in West Virginia where a sudden epidemic of WNV infection was reported in 2012.Our results emphasize the value of hydroclimatic processes estimated by satellite remote sensing, as well as continued environmental surveillance of mosquitoes, because when a vector-borne infection like WNV is discovered in contiguous regions, the risk of spread of WNV mosquitoes increase at points where appropriate hydroclimatic processes intersect with the vector niche.

View Article: PubMed Central - PubMed

Affiliation: Department of Civil and Environmental Engineering, West Virginia University , Morgantown, WV , USA.

ABSTRACT
West Nile virus (WNV), mosquito-borne and water-based disease, is increasingly a global threat to public health. Since its appearance in the northeastern United States in 1999, WNV has since been reported in several states in the continental United States. The objective of this study is to highlight role of hydroclimatic processes estimated through satellite sensors in capturing conditions for emergence of the vectors in historically disease free regions. We tested the hypothesis that an increase in surface temperature, in combination with intensification of vegetation, and enhanced precipitation, lead to conditions favorable for vector (mosquito) growth. Analysis of land surface temperature (LST) pattern shows that temperature values >16°C, with heavy precipitation, may lead to abundance of the mosquito population. This hypothesis was tested in West Virginia where a sudden epidemic of WNV infection was reported in 2012. Our results emphasize the value of hydroclimatic processes estimated by satellite remote sensing, as well as continued environmental surveillance of mosquitoes, because when a vector-borne infection like WNV is discovered in contiguous regions, the risk of spread of WNV mosquitoes increase at points where appropriate hydroclimatic processes intersect with the vector niche.

No MeSH data available.


Related in: MedlinePlus