Updated: February 2001
Infectious diseases not necessarily common in Canada can occur and may even be widespread in other countries. Standards of hygiene and medical care may differ from those at home. Before departure, you should learn about the health conditions in the country or countries you plan to visit, your own risk of disease and the steps you can take to prevent illness.
The risk is yours
Your risk of acquiring
a disease depends on several factors. They include: your age,
gender, immunization status and current state of health; your
itinerary, duration and style of travel (e.g., first class,
adventure) and anticipated travel activities (e.g., animal contact,
exposure to fresh water, sexual contact); as well as the local
disease situation.
Risk assessment consultation
The Public
Health Agency of Canada strongly recommends that your travel plans
include contacting a travel medicine clinic or physician 6 to 8
weeks before departure. Based on your individual risk assessment, a
health care professional can determine your need for immunizations
and/or preventive medication (prophylaxis) and advise you on
precautions to avoid disease.
Some facts from the experts
The information below has been developed and is updated in
consultation with Public Health Agency of Canada's Committee to Advise on Tropical
Medicine and Travel (CATMAT). The recommendations are intended
as general advice about the prevention of measles for Canadians
travelling internationally.
Disease profile |
Ross River virus (RRV) infection, or epidemic polyarthritis, is a viral infection spread by infected mosquitoes. Fewer than one in three humans will become infected after being bitten by an infected mosquito. It generally results in a self-limiting flu-like illness, but it can cause long-term joint pain and fatigue. The virus causing RRV infection is a member of the Togaviridae family of viruses.
Ross River virus infection can be transmitted to humans by the bite of an infected mosquito. A variety of mosquito species can transmit RRV, biting day and/or night.
For instance, in Australia the following species have been found to be RRV carriers:
Ross River virus infection cannot be passed from person to person.
Geographic distribution and incidence trends |
Ross River virus infection is found in all States and Territories of Australia, but occurs more often in the northern States and in coastal areas. Infection can occur year round, but is more common from late November to the end of April during the wet season when mosquito activity increases. Ross River virus is also found in Papua, New Guinea, areas of Indonesia and the Western Pacific islands.
Symptoms |
Incubation of the disease following a bite of an infected mosquito varies from 3 days to 3 weeks with symptoms developing within 7 to 14 days. Symptoms of RRV infection vary person to person, but commonly include painful and swollen joints, sore muscles, aching tendons, skin rash, fever, fatigue, headache and swollen lymph nodes. Less common symptoms include sore eyes, sore throat, nausea and tingling in the palms of the hands and soles of the feet. Some individuals will experience reoccurring symptoms, especially joint pain, fatigue, lethargy and depression that may continue for up to 1 year following infection. Symptoms disappear eventually and leave few or no after-effects. Children are less troubled by the symptoms of RRV infection than adults; the disease is usually milder and runs a shorter course. Most people who have been exposed to RRV are immune for life.
Treatment |
There is no vaccine and no specific treatment for Ross River virus infection, but treatment of symptoms can reduce discomfort. Medical treatment is aimed at easing joint pains and swelling, and minimizing fatigue and lethargy.
Prevention and personal precautions |
The Public Health Agency of Canada strongly recommends that travellers consult their private physician or a travel medicine practitioner to discuss their individual risk of exposure to Ross River virus infection. If you are travelling to RRV-endemic areas, you should take the following personal precautions to avoid being bitten at any time.
Personal measures to avoid mosquitoes:
Protective clothing:
- Wear clothing that reduces the amount of exposed skin.
- Wear light-coloured, long-sleeved shirts, long pants, socks and shoes when outdoors between dusk and dawn (note: dark colours attract mosquitoes).
- Impregnate all clothing with 0.5% permethrin to make them repellant.
Screens and bed nets:
- Sleep inside screened areas, under a mosquito net or in an air-conditioned room.
- Use bed nets that are rectangular in size, impregnated with permethrin every six months and tucked tightly under the mattress before dusk (note: treated bed nets are available in Canada).
Insect repellent:
- apply DEET-containing insect repellent to exposed skin when outdoors between dusk and dawn.
Of the insect repellents registered in Canada, those containing 'N, N diethyl-m-toluamide' (DEET) are the most effective. Although the concentration of DEET varies from product to product, repellency rates are largely equivalent. In general, higher concentrations protect for longer periods of time, but there is little advantage in the duration of repellence with DEET concentrations greater than 50%, and there may be additional risk of toxicity with higher concentrations. New micro-encapsulated products containing 33% DEET are registered in Canada, and they should provide up to eight hours of protection.
Children and DEET
In rare instances, application of insect repellents with DEET has been associated with seizures in young children (14 cases have been reported in over 30 years of DEET use and billions of applications every year). The actual concentration of DEET varies among repellents and can be as high as 95%. However, repellents with DEET concentrations of 10% are very effective and should last 3 to 4 hours. For children, DEET in a concentration of not more than 10% should be applied sparingly to exposed surfaces only and washed off after children come indoors.The likelihood of adverse reactions can be minimized by the following precautions:
- Apply repellent sparingly and only to exposed skin.
- Avoid applying high concentration products.
- Avoid applying repellents to portions of children's hands that are likely to contact the eyes or mouth.
- Never use repellents on wounds or irritated skin.
- Wash repellent-treated skin after children come indoors. If a reaction to insect repellent is suspected, wash treated skin and seek medical attention.
In Canada, DEET products are not recommended for use in children less than 2 years of age. The risk of DEET use vs. the risk of exposure to life-threatening mosquito-borne diseases must be assessed by an individual's physician or travel medicine practitioner. For more information on insecticide use, go to: Safety Tips on Using Personal Insect Repellent.
Some things to think about... |
For more information...