Time To Get Your Flu Shot Again!

Every year around this time, our family medicine clinic really starts to get busy. School is back in session, the weather starts getting cooler, the leaves start changing, and the season's flu vaccine becomes available.
Older patients wait with baited breath, like it's Christmas time, constantly phoning to see whether the serum is in yet.

We hold flu vaccine clinics for several weeks every fall, and the line ups prior to the doors opening are like that of a rock concert, or Boxing Day sale. That's great, although I wish we could get more kids in, as they tend to be most at risk and most likely to spread the flu.



What is the Flu Anyway?
When we take about the "flu", we're using the short version of influenza, a highly contagious virus. In North America, the bug causes a respiratory illness, generally peaking in fall and winter. There are 2 main strains, Influenza A and Influenza B, with the "A" strain generally being more contagious and severe. Symptoms typically are sudden in onset and include headache, fever, sore throat, cough, runny noses and itchy eyes. Often muscles are very achy, especially in the low back. The course will typically last a week to 10 days and can really knock you off your feet. Generally speaking, we distinguish influenza from the common cold by the rapid onset, the severity with which it hits you, and body aches. The common cold is usually milder. Formal diagnosis must be made by taking a nasopharyngeal (back of your nostrils into your throat) swab.



How do we Treat the Flu?
Treatment for the flu is generally symptomatic and supportive, as the symptoms, although significant, are self limiting. Lots of fluids,Tylenol or Ibuprofen for aches and fever are really all that are necessary.

There are also antiviral medications like Tamiflu  or Relenza that have been shown to shorten the course of the flu by 1-2 days if started immediately. This may be of benefit if work is time critical or an important event is imminent.

Prevention 
Not getting sick is always the best option if possible. Keeping hands as clean as possible, coughing into your sleeve, and avoiding contact will sick people are always good choices. Getting the Flu Vaccine is the best method of staying healthy this winter.

Every year, a prediction of the prevailing influenza strains is made and 3 vaccines are incorporated into the annual influenza vaccine. This is because the influenza virus is constantly mutating and new strains become prevalent. The vaccine always contains 2 strains of the Influenza A and 1 strain of Influenza B. This year's strains are:

• A/California/7/2009 H1N1
• A/Victoria/361/2011 H3N2
• B/Wisconsin/1/2010

Who Should Get Vaccinated?

In Ontario, we vaccinate everyone from 6 months of age onward. Highest risk groups should be given priority, which include the elderly (>65), those with chronic medical conditions (diabetes, heart disease. . .), those in long term facilities, pregnant women, and those coming in contact with high risk individuals (ie, health care workers, community workers like teachers, etc.)

Overall, the benefits are large, and the risks are very low, so I strongly encourage everyone to get their flu shot again this year!

Let me know - Have you gotten your shot yet? 

Stress Fractures: Are You At Risk?

With the Olympics now well under way, it never ceases to amaze me what the human body can do. Yes, the accomplishments and speed of the runners and swimmers is outstanding, but I see these guys in clinic everyday. What I don't see as often are the incredible gymnasts and divers that tumble and fly through the air. I am amazed, not so much that they don't injure themselves on their landing or entry into the water. They're too good at this level to miss by much. What amazes me is that they don't have more repetitive injuries like stress fractures.



Back in the "olden" days, stress fractures were extremely rare. They tended only to occur in highly repetitive activity. The old nickname was "march" fracture, due to the frequency they occurred in the military.  Other activities simply weren't done often enough to cause the fractures. These days, it would be a slow week at the sport clinic if I didn't see one or two stress fractures come through the doors.
In fact, in my practise, the group I most often see now, are middle aged females training for their first long distance race.

Risk Factors


1. Highly Repetitive Activity.
Sports involving running, where the body is exposed to the same pounding over and over are at most risk. Other activities like gymnastics, figure skating, rowing are also at risk, where the same motion occurs over and over.

2. Being Female
Simply being female is, unfortunately a risk factor for a number of reasons. Bone density may not be as strong, if periods aren't regular, it contributes to increasing risk, and if body fat is extremely low, it elevates the risk of stress fractures.
There is a syndrome called the female athlete triad, which consists of amenorrhea (lack of periods), low bone  density, and eating disorders (like anorexia), which should be screened for if a woman comes in with stress fractures.

3. Sports Where Weight/Appearance is an Issue
Any sport where the athlete has to "make" weight, like rowing or even boxing can put one at risk, as these athletes commonly have to drop their weight dramatically over a short period of time. Appearance sports like gymnastics, diving, figure skating etc, also contribute to weight/body image issues.



Bones at Risk


The areas at risk depend a lot on what the activity is that you are doing. Runners tend to experience stress fractures in the foot, most commonly at the 2nd metarsal, and the navicular (inside portion of the foot). They can also fracture the tibia, and more rarely in the hip.

Gymnasts and divers, who commonly put many times their body weight through their wrists, can cause stress fractures in the distal radius, and a number of small bones in the wrist. If growth plates are not closed yet, these can also occur in the elbow.

How Do I Prevent Stress Fractures?
At a non-Olympic level, the more cross-training you can do the better. Try to change the activity you do each day. If you're a runner, cycle of use an elliptical machine on alternate days.

Eat! Not a problem for most of us, but if you are involved in an appearance sport, get the advice of a dietician to ensure you are getting enough calories. I can't emphasize this enough. Find out how much calcium/Vitamin D you need for your age and sex. Don't worry about your appearance. You look great. Trust me.

Proper equipment is essential. Runners need to change out their shoes every 6 months, or approximately 500 miles, whichever comes first. Get the right shoe for your foot type. Get proper wrist protection if you dive or tumble. Make sure your skates and technique are correct if you are figure skating.

Women over 65 or those who have other risk factors should have a bone density done.


Have you ever had a stress fracture? Know anyone at risk? Let me know what you think!

APPENDIX: Quick Screen for Female Athlete Triad
1. Do you ever worry about your body weight/composition?
2. Do you limit/carefully control your food intake?
3. Do you try to lose weight for your appearance/weight due to your sport?
4. Does your weight affect the way you feel about yourself?
5. Have you felt that you have lost control of the way you eat?
6. Do you make yourself throw up after you eat?
7. Do you currently or have you ever suffered from an eating disorder?
8. Do you every eat in secret?
9. At what age was your first period?
10. Do you have regular monthly cycles?
11. How many periods have you had in the last year?
12. Have you ever had a stress fracture?

Answering yes to any of these questions should prompt a further evaluation by a trained sport medicine specialist.

The "SUNSHINE" Vitamin - Vitamin D

There has been a lot of news over the last year or two about the benefits of Vitamin D. A lot of this is potentially exciting, but medical bodies have been at odds over how MUCH exactly to recommend. A lot of the benefits are NOT YET 100% factual, but derived from observational trends.  This is potentially promising and exciting, but we physicians tend to err on the side of caution, rather than go overboard too early. (That can get embarrassing, if the evidence shows us to be wrong down the road. . .)


Let's try and sort out what's worth doing. . .

What does Vitamin D do?
Vitamin D, like all vitamins, is a nutrient that our body can NOT produce on its own, so we need to get it from outside sources.  It has a number of functions in our body:

• Helps the gut to absorb Calcium
• Plays a definite role in Bone strength and structure
• May be cardioprotective. (Low levels increase risk of heart attack and stroke)
• May DECREASE the risk of Colon Cancer
• May Prevent Multiple Sclerosis
• May Prevent Viral Infections like the Flu
• May Decrease the risk of Diabetes.

HOW DO WE GET OUR VITAMIN D?

1.  SUN EXPOSURE
Uncovered skin to sun allows UVB rays to convert Previtamin D to Active Vitamin D3. There are a lot of factors that affect the amount of conversion including the time of year, time of day, skin tone, geographic location, pollution, sunscreen etc., but scientists estimate that anywhere from 5-30 minutes of sun exposure to face, arms and legs twice a week would be more than enough to maintain adequate active Vitamin D stores. The downside is, obviously, that too much sun exposure is a significant risk factor for skin cancer!

I should make special note that in Northern Climates, (including northern U.S. States, and Canada), during winter, an adequate supply from sun is NOT available, and supplements should be considered, especially for infants and young children.




(Yes, that is Canadian Milk in a Bag on the right!)


2,  FOOD SOURCES


Other than some fatty fish, very few foods contain any significant levels of Vitamin D. Given this, some foods are fortified with Vitamin D, the most important being MILK. Some juices, yogurt, cereals etc are also fortified, but you need to look carefully to ensure this.

ALL infant formulas in the US and Canada are fortified by law. (Please note, although I strongly encourage breast feeding, the amount of Vitamin D in breast milk is NOT adequate on its own).


(chart from NIH, Office of Dietary Supplements)  - NIH

Table 3: Selected Food Sources of Vitamin D [11]

Food	IUs per serving*	Percent DV**
Cod liver oil, 1 tablespoon	1,360	340
Swordfish, cooked, 3 ounces	566	142
Salmon (sockeye), cooked, 3 ounces	447	112
Tuna fish, canned in water, drained, 3 ounces	154	39
Orange juice fortified with vitamin D, 1 cup (check product labels, as amount of added vitamin D varies)	137	34
Milk, nonfat, reduced fat, and whole, vitamin D-fortified, 1 cup	115-124	29-31
Yogurt, fortified with 20% of the DV for vitamin D, 6 ounces (more heavily fortified yogurts provide more of the DV)	80	20
Margarine, fortified, 1 tablespoon	60	15
Sardines, canned in oil, drained, 2 sardines	46	12
Liver, beef, cooked, 3 ounces	42	11
Egg, 1 large (vitamin D is found in yolk)	41	10
Ready-to-eat cereal, fortified with 10% of the DV for vitamin D, 0.75-1 cup (more heavily fortified cereals might provide more of the DV)	40	10
Cheese, Swiss, 1 ounce	6	2

* IUs = International Units.
** DV = Daily Value. DVs were developed by the U.S. Food and Drug Administration to help consumers compare the nutrient contents among products within the context of a total daily diet. The DV for vitamin D is currently set at 400 IU for adults and children age 4 and older. Food labels, however, are not required to list vitamin D content unless a food has been fortified with this nutrient. Foods providing 20% or more of the DV are considered to be high sources of a nutrient, but foods providing lower percentages of the DV also contribute to a healthful diet.

How Much Should I Take?


Various Governing Medical Bodies have come out with recommendations based on the available incomplete evidence and studies. Many studies are currently underway trying to come out with an appropriate safe number while maximizing benefit. Given that toxicity is unlikely to occur below an intake of 10,000 IU Vitamin D a day, I believe the Canadian Guidelines (CMAJ, Sept 7, 2010) of 1000 IU of Vitamin D/ day is an appropriate place to start. Here is the equivalent link for the U.S. (US Preventive Task Force, Dec 2011)



Bottom Line: Get a little bit of sun, drink your milk, and in the wintertime take 1000 IU Vitamin D supplement.

Please let me know what you think of the blog so far. Loving the comments and suggestions!

(Special Thanks to the SE Water Cooler)