An infection can often make you feel miserable. It may even mean a visit to your doctor. Bacteria are one cause of such infections. They live on us normally – but sometimes they get out of hand, as with strep throat. Taking antibiotics helps to get bacterial numbers back to normal and makes us feel better. Viruses are the other large group of organisms causing infections.
Viruses are tricky - they are unable to reproduce themselves so they hide in your cells and borrow your machinery. This is part of the reason we often do not have good ways of killing them. Many of our medicines cannot tell which cells have been taken over by the virus.
Antiviral medicines have been developed for some diseases caused by viruses, including influenza, chicken pox and HIV (human immunodeficiency virus). In your lifetime, you are exposed to hundreds of viruses that your body is able to fight off, such as the common cold. Other viruses are more serious and can even cause death. Currently no antiviral medicines are effective against them.
West Nile (WN) is a new name in the virus family for those of us in North America, but it’s actually been around for a while. It was first identified in 1937 in a sick woman from the West Nile district in Uganda. (This explains the name.) The virus was happy to live in the Eastern part of the world - places like Africa, Asia and the Middle East. It usually caused only mild sickness in humans.
In 1999, a group of people in New York City got ill and after careful detective work, WN virus was identified as the cause. How did it make its way from Africa? The virus can infect people, birds or mosquitoes (all capable of flying) so it could have been transferred by any one of these. Since WN reached the Big Apple, infected birds, mosquitoes and even people have been found in many areas in the United States and Canada.
WN virus is spread to humans by the bite of an infected mosquito. It does not spread from one person to another. A mosquito becomes infected after feeding on a bird that carries the virus.
Most times when there has been an outbreak of WN virus in humans, people noticed more dead birds than normal (especially those from the crow family). One way of keeping watch for the disease is to monitor what it is doing in other animals, particularly birds.
In places where WN virus has been found, one out of every 100 mosquitoes will carry the virus. If you are a healthy person and are unlucky enough to get bitten by that mosquito, you have about a one in five chance of feeling ill. This will happen about three to 15 days after being bitten. You may have symptoms of fever, headache, or aches and pains. Sounds like the flu, right? Most people’s symptoms are so mild, they will not even bother go see their doctor.
WN virus is seen mostly in the late summer and early fall, because that is the time when mosquitoes are around to bother us. Infection with the virus gets more risky if your immune system is weakened by another disease or if you are over the age of 50. The risk increases with age and the elderly are more vulnerable. People in this group may have the infection spread to their brain. This makes them very ill.
Symptoms may include high fever, stiff neck, muscle weakness, tremors or change in personality, and sometimes may lead to death. No specific treatment for the virus exists, because it hides in your cells. Health care providers can help the sick person fight off the virus by giving fluids, boosting nutrition and generally keeping the person comfortable.
Scientists are busy trying to make a vaccine against the virus. A vaccine would teach our bodies to recognize the WN virus early and kill it before it has a chance to make us sick. Despite all the talk about WN virus, it is uncommon and the chance of getting sick from it even less so. A vaccination might only be given to those at high risk of being bitten by mosquitoes or those who are not healthy.
Mosquitoes are the nasty creatures that carry the disease and pass it to humans. Since we will never be rid of mosquitoes, the best way to reduce your risk of being infected is to lower your chance of being bitten. There are a few ways to do this.
One is to decrease the number of mosquitoes around you. Make sure your property does not have any mosquito breeding grounds, which includes any still water. Flowerpots, rain barrels and old tires in your yard would all be perfect havens for mosquitoes and their eggs. City workers may also spray breeding grounds with chemicals to kill mosquito eggs if it is an ideal year for the creatures.
Other ways to reduce the chance of bites are to avoid being outside during the hours when mosquitoes are on the prowl (dusk to dawn), covering up exposed skin with clothes, and making windows and doors mosquito-proof. Use repellants that have DEET (a chemical that doesn’t harm us but mosquitoes find really unappetizing). Health Canada’s Pest Management Regulatory website (www.hc-sc.gc.ca/pmra-arla) has more useful information about insect repellents. Be careful when travelling to warm climates that have mosquitoes, regardless of the time of year.
The WN virus has been worrisome in the past few years since it is new to us in the western part of the world. The chance of becoming infected with the virus is small and the risk of getting very ill from it even less likely. Still, elderly or unwell people must be very careful about avoiding mosquitoes at home and when travelling. The virus has appeared in new places, so Health Canada has a regularly updated website about where the disease has been found (www.hc-sc.gc.ca/english/disease/west_nile.html).
If you think you or someone you know may be infected with the WN virus, see your doctor or your local public health unit. Your chance of having been infected with the disease and your risk of becoming ill will be assessed. The doctor can then examine you for signs of illness and may order blood tests to see if WN virus is the cause.
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