Health Issues at the Dharma Centre
Medical Screening
Health Issues have become an item of increasing concern for everyone recently. As many are aware, the Dharma Centre has for some time had in place a Health Screening process in order to protect guests from the spread of illness. At the time of registration, all guests are asked a series of standard questions in order that we might ascertain, to the degree possible, whether or not any health or safety risk is posed by their attendance - to fellow course participants as well as to themselves.
The standard that needs to be strictly adhered to for attendance at courses is that people are in good physical and emotional health, and our Staff are required to ensure that everyone undertakes the Health Screening process. We would ask that all applicants help as much as possible with this important step.
Mosquito-borne illness
With regard to possibilities of mosquito-borne illness, the Centre’s policy is to ensure guests have available the appropriate information, as well as adequate and appropriate mosquito repellant. In our research, we find that the risks are low and the measures individuals can take to reduce them still further are clear and simple.
Below is some information to help guests sensibly evaluate the risks, and the precautions they may take to be adequately protected.
West Nile Virus
(information provided by Ontario Ministry of Health and Long-Term Care )(West Nile Virus "Fact Sheet" from the Ontario Ministry of Health .pdf - 150kb)
The West Nile virus is an illness that spreads from mosquitoes to humans. Usually the mosquito has contracted the virus by biting an infected bird. The virus is not spread from person to person, and cannot be spread from a bird to a human. International research has linked transmission of West Nile virus through blood transfusion, and further study is being done to confirm if the virus can be passed from a mother to her unborn child and through breast milk.
Mosquitoes become infected with the virus and spread the disease by biting birds or humans. Sometimes the virus spreads from mosquitoes to horses and other animals. The virus is stored in the mosquito's salivary glands, and infected mosquitoes transmit West Nile virus to humans and animals while biting to take blood. The virus then multiplies in the blood and travels to the brain. It interferes with normal central nervous system functioning and causes inflammation of brain tissue.
West Nile virus was first found in Uganda in 1937, and was confined to Africa, the Indian sub-continent and parts of the Middle East and Europe for decades. It then sparked alarm after being detected in 1999 in New York City, where seven people died. It officially arrived in Ontario in 2002.
Recognizing the disease
Overall, most doctors believe that the risk of people becoming seriously ill with West Nile is extremely small. Only one in five people who contract the virus show any symptoms. Most with the virus have symptoms that are mild and flu-like. About 20 per cent of those infected may develop West Nile fever - a milder form of the virus that includes fever, headache, muscle aches and a rash that clears up in seven to 10 days. The U.S. Centers for Disease Control and Prevention estimates that fewer than one per cent of those infected develop severe symptoms and fewer than that experience life-threatening complications.
One out of 150 infected people will develop a serious neurological illness, such as encephalitis (an inflammation of the brain). West Nile virus can cause the brain or spinal cord to swell and block the flow of blood to the brain. This could lead to a coma, paralysis, or even death. However, these extreme reactions tend to appear mostly in people who are over 65 or have weakened immune systems. Of those who become seriously ill, approximately one in 10 will die.Even though the majority of people with mild flu-like symptoms may not need blood tests for West Nile, you should consult your doctor if you have the following symptoms:
Prevention is the best protection
- fever
- muscle weakness
- severe headache, stiff neck
- convulsions or seizures
- sudden sensitivity to light or an inability to perform routine tasks
- extreme swelling or infection at the site of a mosquito bite
As the virus is only spread by mosquitoes, staying inside from dusk to dawn and wearing long-sleeved clothing are your best bets, but if you are going to be exposed to insects, your options include:
Insect repellants:
substances applied to exposed skin or to clothing that repel but do not kill insects. Most contain DEET as their active ingredient.Insecticide spray cans :
- Look for repellents with no more than 30 per cent DEET for adults and no more than 10 per cent DEET for children. Children should not have DEET-containing repellant on their hands, and children under six months of age should not have DEET applied (it is recommended, where there is a high risk of complications to the child from insect bites, that DEET may be considered for children aged six months to two years). Pregnant women can apply repellant to their clothes only, but not directly on their skin.
- Neck, wrists and ankles are important areas to apply the repellent to, and care must be taken to avoid mucous membranes (nose and eyes). When applied on the skin, the repellent effect may last from 15 minutes to 10 hours, depending on climate, the product's composition and the type of bug you are trying to repel. When applied on clothes, the repellency effect lasts longer.
Effective for an immediate knockdown and killing effect, but have little effect once the air has cleared. They are best used in combination with other deterrents.Mosquito nets :
Ideal for travelers and campers, and some types are available with insecticide in their material. Look for a mesh size of less than 1.5 mm, and repair any holes immediately.
Comparative Efficacy of Insect Repellents against Mosquito Bites
(information provided by New England Journal of Medicine )ABSTRACT
Background
The worldwide threat of arthropod-transmitted diseases, with their associated morbidity and mortality, underscores the need for effective insect repellents. Multiple chemical, botanical, and "alternative" repellent products are marketed to consumers. We sought to determine which products available in the United States provide reliable and prolonged complete protection from mosquito bites.
Methods
We conducted studies involving 15 volunteers to test the relative efficacy of seven botanical insect repellents; four products containing N,N-diethyl-m-toluamide, now called N,N-diethyl-3-methylbenzamide (DEET); a repellent containing IR3535 (ethyl butylacetylaminopropionate); three repellent-impregnated wristbands; and a moisturizer that is commonly claimed to have repellent effects. These products were tested in a controlled laboratory environment in which the species of the mosquitoes, their age, their degree of hunger, the humidity, the temperature, and the light–dark cycle were all kept constant.
Results
DEET-based products provided complete protection for the longest duration. Higher concentrations of DEET provided longer-lasting protection. A formulation containing 23.8 percent DEET had a mean complete-protection time of 301.5 minutes. A soybean-oil–based repellent protected against mosquito bites for an average of 94.6 minutes. The IR3535-based repellent protected for an average of 22.9 minutes. All other botanical repellents we tested provided protection for a mean duration of less than 20 minutes. Repellent-impregnated wristbands offered no protection.
Conclusions
Currently available non-DEET repellents do not provide protection for durations similar to those of DEET-based repellents and cannot be relied on to provide prolonged protection in environments where mosquito-borne diseases are a substantial threat.
Protection Times of Insect Repellents
Product and manufacturer Active ingredient and concentration (%) Complete protection time (minutes) OFF! Deep Woods (SC Johnson) DEET (23.8) 200 to 360 Sawyer Controlled Release (Sawyer) DEET (20) 180 to 325 OFF! Skintastic (SC Johnson) DEET (6.65) 90 to 170 Bite Blocker for Kids (HOMS) Soybean oil (2) 16 to 195 OFF! Skintastic for Kids (SC Johnson) DEET (4.75) 45 to 120 Skin-So-Soft Bug Guard Plus (Avon) IR3535 (7.5) 10 to 60 Natrapel (Tender) Citronella (10) 7 to 60 Herbal Armor, (microencapsulated) (All Terrain) Citronella (12); peppermint oil (2.5); cedar oil (2); lemongrass oil (1); geranium oil (0.05) 1 to 55 Green Ban for People (Mulgum Hollow Farm) Citronella (10); peppermint oil (2) 1 to 45 Buzz Away (Quantum) Citronella (5) 5 to 30 Skin-So-Soft Bug Guard (Avon) Citronella, (0.1) 1 to 30 Skin-So-Soft Bath Oil (Avon) Uncertain* 1 to 30 Skin-So-Soft Moisturizing Suncare (Avon) Citronella (0.05) 1 to 15 Gone Original Wristband (Solar Gloooow) DEET (9.5) 0.17 to 1.33 Repello Wristband (Repello Products) DEET (9.5) 0.17 to 0.63 Gone Plus Repelling Wristband (Solar Gloooow) Citronella (25) 0.17 to 0.48 DEET = N,N-diethyl-3-methylbenzamide (formerly known as N,N-diethyl-m-toluamide); HOMS = Home Operations and Management Systems; IR3535 = ethyl butylacetylaminopropionate.
*--This product contains mineral oil, isopropyl palmitate, dicapryl adipate, fragrance, dioctyl sodium sulfosuccinate, butylated hydroxytoluene, and carrot oil.
Adapted with permission from Fradin MS, Day JF. Comparative efficacy of insect repellents against mosquito bites. N Engl J Med 2002;347:16.
Incidents of West Nile Virus in Ontario during the previous season (2002)
(information provided by Ontario Ministry of Health and Long-Term Care )
The chart below shows probable and confirmed positive West Nile virus tests on humans in Ontario in 2002.
Region
Total Probable Cases
Total Confirmed Cases
Haliburton-Kawartha-Pine Ridge (in which the Centre is located)
0
0
Niagara
3
16
Muskoka-Parry Sound
0
1
Perth
0
1
Toronto
43
127
ONTARIO TOTAL
85
307
The chart below shows the list of birds that have been confirmed or presumed positive for West Nile virus in Ontario in 2002.
Region
First Positive Bird Found
Last Positive Bird Found
Total Positive
Haliburton-Kawartha-Pine Ridge (in which the Centre is located)
July 18, 2002
August 6, 2002
5 (confirmed)
Muskoka-Parry Sound
July 17, 2002
September 6, 2002
4 (confirmed)
Niagara
July 11, 2002
August 6, 2002
11 (confirmed)
Ottawa
July 23, 2002
August 7, 2002
4 (confirmed)
Perth
July 2, 2002
August 3, 2002
8 (confirmed)
Peterborough
N/A
August 22, 2002
4 (confirmed)
Toronto
July 3, 2002
August 24, 2002
8 (confirmed)
ONTARIO TOTAL
281 confirmed
The chart below shows pools (groups) of mosquitoes that have tested positive for West Nile virus in Ontario in 2002.
Region
First Positive Pool Found
Last Positive Pool Found
Total Positive Pools
Haliburton-Kawartha-Pine Ridge (in which the Centre is located)
August 29, 2002
August 29, 2002
1
Niagara
July 30, 2002
September 20, 2002
15
Hamilton
July 25, 2002
September 11, 2002
11
Perth
July 30, 2002
August 28, 2002
4
Peterborough
August 29, 2002
September 5, 2002
3
Toronto
July 23, 2002
October 1, 2002
175
ONTARIO TOTAL
598
Links to further information
Ontario Ministry of Health and Long-Term Care - Public Information - West Nile Virus
Current Status
Consumer InformationWest Nile Virus Surveillance Information - Health Canada
United States Centers for Disease Control and Prevention - West Nile Virus Home Page
Health Canada - Safety Tips on Using Personal Insect Repellents
Canadian Cooperative Wildlife Health Centre - West Nile Virus Surveillance Program 200