Researchers develop model to help control West Nile outbreak
A University of Alberta researcher has developed the first model to predict risk of West Nile virus in North America–a tool that could help prevent the infectious disease from becoming an outbreak.
Dr. Marjorie Wonham and her research team from the Centre for Mathematical Biology at the University of Alberta, created a simple mathematical model using the dead bird counts collected in New York in 2000. Her research is published in the current issue of the Royal Society of Londons journal Proceedings B. Tomas de-Camino Beck and Mark Lewis are co-authors on the paper.
West Nile virus is an emerging infectious disease in North America that spreads primarily through contact between birds and mosquitoes. It can be lethal to birds, horses and humans. One of the key findings from Wonhams work is that chance of a virus outbreak is decreased by removing mosquitoes but is actually increased by removing birds. The model provides a new analytical method for determining necessary mosquito control levels.
“This virus is endemic and were probably never going to get rid of it completely unless we say that were going to kill all the mosquitoes in the world–thats not going to happen,” said Wonham. “What this work does is tell you just what percentage of mosquitoes is necessary to kill to keep the virus below an outbreak. This is a first step towards effective management.”
The research group set up parameter values from published scientific papers on mosquito biology, crow biology and West Nile biology. In order for a specific region to use this model, officials could tailor such parameters as mosquito life span, biting rate and crow life span to the data in their area. For example, since summer in Edmonton is short and dry, the mosquito lifecycle might be quite different than in the longer, more humid summer of New York.
Currently mosquitoes are killed through the application of chemical larvicides to the water, filling in the wetlands to remove the habitat and as a last resort, spraying chemicals to kill the adult species.
“Since applying chemicals and filling in wetlands costs money and causes environmental damage, one would ideally use the minimum amount of control that would still be effective in preventing outbreak,” said Wonham. “Our model lets you calculate the threshold mosquito population for West Nile outbreak–you just have to keep them below the threshold level. This means, we would hope, minimal economic cost and environmental damage while still preventing outbreak.”
Mathematical models have been used to manage diseases such as malaria but this is the first one to deal with West Nile.
Alle Nachrichten aus der Kategorie: Health and Medicine
This subject area encompasses research and studies in the field of human medicine.
Among the wide-ranging list of topics covered here are anesthesiology, anatomy, surgery, human genetics, hygiene and environmental medicine, internal medicine, neurology, pharmacology, physiology, urology and dental medicine.
Climate change drives plants to extinction in the Black Forest in Germany
Climate change is leaving its mark on the bog complexes of the German Black Forest. Due to rising temperatures and longer dry periods, two plant species have already gone extinct…