Summer is here, so are the mosquitos, ticks and other insects. The recent heavy rains and warm temperatures have led to the rapid multiplication of insects.
Naturally, the more time we spend outdoors, higher are our chances of being bitten by these insects, some of which may carry disease-causing viruses or bacteria.
Most insect bites are harmless, and do not cause serious illnesses. Nevertheless, mosquitos can carry several encephalitis-causing viruses.
West Nile virus is transmitted by mosquitoes of the Culex genus and was introduced into Canada in 2001.
The number of annual cases of West Nile varies; some of this variation is believed to be related to temperature and precipitation patterns.
Most people infected with the virus have no signs or symptoms.
There is an incubation period ranging from two to 14 days between the mosquito bite and the appearance of signs and symptoms of the illness.
About 20 per cent of people develop the mild West Nile fever, with fever, headache, body aches, vomiting, diarrhea, fatigue and skin rash. These symptoms usually last a few days and resolve on their own.
About one per cent of infected people develop complications such as encephalitis and meningitis.
These individuals would go on to develop severe headache, neck stiffness, disorientation, tremors or muscle jerking, seizures, and partial paralysis or muscle weakness
These symptoms of encephalitis or meningitis can linger for weeks or months. Certain neurological effects, such as muscle weakness, can be permanent.
West Nile virus is diagnosed by the presence of antibodies in the blood and spinal fluid.
Among ticks the blacklegged variety, Ixodes scapularis, is the one commonly found in Alberta. It can carry the bacterium B. burgdorferi which causes Lyme disease and Rocky Mountain Spotted Fever (an encephalitis), and the lesser-known Powassan virus (POWV).
Lyme disease is the most common tick-borne disease in North America. Lyme disease can affect humans, wildlife, and domestic animals.
It is important to note that the risk of getting Lyme disease from a tick bite in Alberta is considered low.
Early symptoms of Lyme disease may include fever, headache, muscle and joint pain, fatigue, and weakness or paralysis of the muscles of the face. Later symptoms of untreated Lyme disease may include on-going muscle and joint problems, abnormal heartbeat, nervous system disorders, and brain dysfunction.
Lyme disease is usually diagnosed based on history of exposure to ticks, presence of flu-like symptoms, physical exam, and presence of antibodies in blood.
It is important to ensure that laboratory testing is done correctly using a two-step testing process in an accredited laboratory.
In Alberta, laboratory testing for the first step is done by the Provincial Laboratory for Public Health and the second step by the National Microbiology Laboratory in Winnipeg.
If you spot a tick on your cloth or your skin, remove it carefully using a tweezer or a plastic tick remover (store-bought) and disinfect the bite site and wash your hands with soap and water.
Alberta Health suggests that you submit it for testing as part of tick surveillance, to AHS environmental health office.
What can you do to protect yourselves from these insect bites?
Walking on cleared trails, avoiding tall grass or wooded areas, wearing light-coloured long-sleeved shirt, long pants with legs tucked into socks or boots, applying a bug spray containing DEET or Icaridin over the clothes, checking yourself and your pets thoroughly for ticks after a walk outdoors, are steps you can take to protect yourself.
Padmaja Genesh, who holds a bachelor degree in medicine and surgery as well as a bachelor degree in Gerontology, has spent several years teaching and working with health care agencies. Please send your comments to firstname.lastname@example.org