Archive for July, 2008

Vegetable wars – tomatoes back in the salad, peppers out

Thursday, July 17th, 2008

Tracking down the source of infection outbreaks is tough (see Chapter 2 in Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infectons (ASM Press, Washington, D.C., 2008). The disease detectives from your state and local health departments, as well as from the Centers for Disease Control and Prevention (CDC) do extensive interviews of  infected individuals in an outbreak, and compare their exposures to uninfected individuals. As with the recent national Salmonella outbreak, sometimes the clues that emerge are mixed or muddied. Whereas 5 weeks ago tomatoes seemed to be the most likely culprit (see Dr. Rotbart’s GERMBlog entry from June 8, 2008), now attention is focused on peppers (jalapeno and serrano varieties). This doesn’t yet absolve tomatoes in the earlier cases, but the farms producing them back in April and May are no longer in production and there are still cases of Salmonella occurring, albeit at a slower rate.  So…the investigations go on. One unifying hypothesis might be that salsa containing both tomatoes and peppers is at the root of some of the cases – but not yet tested or proven.

This is not a case of crying wolf (or crying tomatoes, as the case may be), nor a case of a botched investigation. Rather, it’s evidence that tracking germ routes and germ roots is challenging and often time-consuming (see Chapter 2 in Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infectons).

Adolescent Health – Reactions and Over-reactions to the Cervical Cancer Vaccine.

Tuesday, July 15th, 2008

 

In the past several weeks, concerns have been raised about the safety of the cervical cancer vaccine (Gardasil). There have been 10 reported cases of a paralyzing neurological condition called Guillain-Barre Syndrome (GBS). Lost in the commotion is the fact that GBS occurs in the teen population even without vaccination – and the predicted number of cases among the 8 million girls and young women who have received Gardasil would have been 40 cases WITHOUT getting the vaccine That means, there are actually fewer cases of GBS in those receiving the vaccine than would have been expected WITHOUT the vaccine!

 

Here’s a little background about cervical cancer and the Gardasil vaccine:

 

Gardasil protects against infection with certain strains of human papillomaviruses. The human papillomaviruses cause warts, those on the hands and feet, as well as sexually-transmitted genital warts (see Chapter 3, Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections [ASM Press, Washington, D.C., 2008]). Importantly, papillomaviruses also cause most cases of cervical dysplasia and cervical cancer. Papillomavirus infections are the most common sexually-transmitted disease in the U.S.; as many as two-thirds of adolescent girls are infected in some communities studied, and most new infections each year occur in adolescents and young adults. The same papillomaviruses also cause genital cancers in men and some cases of cancers in the mouth. According to the American Cancer Society, as many as 10,000 new cases of cervical cancer are diagnosed each year, virtually all due to the strains of papillomaviruses included in the vaccine. The current vaccine produces high levels of protective antibodies in nearly 100% of women studied. In prevention trials of the vaccine in 16-26 year old girls and women, the vaccine was found to be 95-100% effective in preventing genital warts, cervical dysplasia, and early cancer changes in the cervix. The protection was only against those strains of the virus with which the women had not yet been infected; there was no effect of the vaccine on already existent papillomavirus infections. The vaccine must be given to girls and women before they have the chance to become infected – but even if already infected with one or more of the four high risk strains, immunization was found to be protective against the remaining strains included in the vaccine preparation. Immunity appears to persist for at least 5 years after the vaccine, and at present no booster shots are recommended. Studies are continuing in men – the vaccine produces high levels of protective antibodies in men as well, but it is not yet known if there will be an effect on reducing actual infections as has been shown for women.

 

Safety: As with most vaccines, local reactions (pain, redness, swelling) at the site of injection are the most common side effects; 95% of all bad reactions reported so far with Gardasil have been of this minor variety. Fever developed in 10% of those vaccinated, but also in 9% of those getting a placebo (see Chapter 12, Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections ). Among the 16 million doses of Gardasil given to approximately 8 million girls and young women to date, only 7 percent have been classified as “serious” – this compares with a 10-15% “serious” reaction rate reported for other vaccines which are also considered to be very safe. 

 

While the Gardasil vaccine should continue to be regarded as a very safe vaccine, certain cautionary notes are worth mentioning. Although the vaccine protects against the most common papillomaviruses that cause genital warts and cervical cancer, it does not protect against all papillomaviruses or all causes of abnormal cervical changes in women. Pap smears and cervical screening examinations will still be required for those immunized.

 

Many states are now considering mandating immunization against papillomaviruses for all girls entering middle school. It is up to individual states to determine required immunizations for school and day care entry (see Chapter 7, Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections ). Because papillomavirus infections are sexually-transmitted, only sexually active adolescents are at risk. This has caused objections to mandated immunization against papillomaviruses by some parents and religious organizations that prefer abstinence as a preventive against sexually-transmitted diseases. And, indeed, abstinence is preventive against acquisition of this infection. However, studies show that 65-70% of adolescent girls and boys are sexually active by the end of high school and that more than 10% of 11th graders have already had four or more sexual partners. By the timie a woman is 50, there is an 80% chance she will have been infected with papillomaviruses. The vaccine is only effective if given before sexual exposure to the strains in the vaccine occurs (see above). Traditionally, mandated vaccines have been those that prevent infections that readily spread within the school community. The sexual pattern of spread of papillomavirus infections has generated debate regarding whether it satisfies the usual criteria for mandated vaccines. Tetanus immunization also does not satisfy the traditional criterion of classroom contagiousness, but it is included in the diphtheria and pertussis vaccine preparations that do protect against school contagions.

 

Along similar lines, some parents and religious organizations have expressed concern that immunization against a sexually-transmitted disease sends the message to kids that sexual activity is expected and even permissible (see Chapter 7, Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections). Additionally, some have worried that immunized girls might be less cautious sexually because they feel “immune”, and therefore potentially put themselves at risk for other sexually-transmitted diseases and pregnancy.

 

The current vaccine is very expensive – almost $400 for the 3 doses, in addition to clinic visit charges. Some, but not all, health insurance plans cover the vaccine and clinic visits, but many adolescents in the highest risk communities are uninsured.

 

This is a good vaccine and it should be given to adolescent girls to protect them from the potentially devastating effects of papillovirus infections, namely cervical cancer. Headlines are typically misleading. For a guide on how to react, and not over-react, to the news of each day, see Chapter 12 in Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections.  

 

 

Listen to your Grandmother!

Friday, July 4th, 2008

 

In the mid-19th century, a revolution took place in science and medicine. Germs were discovered, and with their discovery, the “germ theory” of disease was born. Of course, today we all know that infections are the result of germs that get into us from another person, from an animal, or from the environment. But, grandmas have long had their own theories about what causes illness.

 

Many of us grew up with grandma teaching us that illness came from being underdressed in cold weather, or overdressed in warm weather. If our hair was wet when we went outdoors, guaranteed sickness. If our feet got wet in the snow or rain, sick again – we had caught a chill! Food and drink, of course, were also critical determinants of health. Hot was healing – chicken soup and oatmeal; but heaven help the poor soul who drank something too cold on a cold day – or, for that matter, on a hot day. Ice was a public health menace. Hot tea with honey was curative; ice tea – are you kidding? If we got enough sleep, we stayed healthy – if not, sickness. Our grandparents thought that stress made us more likely to get sick, and that exercise kept us healthy. The truth about infections rests somewhere between grandma and science. The following paragraphs briefly examine the science behind grandma’s wisdom. For much more on traditional and non-traditional approaches to germ defense, see Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections (ASM Press, Washington, D.C., 2008).

 

Sleep

 

Sleep-deprived rats develop severe, life-threatening infections. In humans, laboratory tests show dramatic effects of sleep-deprivation. When blood tests are done on sleep-depressed adults, all test-tube measures of immunity are weakened. But, what do clinical studies show about the impact of sleep and sleep deprivation on actual infections? Do our kids really get sicker if they don’t get adequate sleep? Although there is no research on sleep-deprivation in kids, adult studies have shown that lack of sleep results in a weakened immune system. In one study, 10 days after receiving the flu vaccine sleep-deprived adults had less than half the amount of flu immunity (protective antibodies measured in the blood) compared with a normal sleep group. Grandma was probably right – your kids’ immune systems need adequate sleep (for much more, see Chapter 11 in Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections).

 

Stress

 

Childhood shouldn’t be stressful – how many of us would instantly trade our adult hassles and headaches for the carefree childhoods we remember? And yet, anyone lifting our kids’ backpacks after school or watching them try out for their competitive soccer teams knows that kids do have stress. Science has looked at two types of stress: short-term (like the big test or the big try-out), and long-term (like divorce or family illness). The effects of the two types of stress are opposite: while long-term stress does weaken the immune system, short-term stress actually boosts immunity! Along with adrenaline that’s released under stressful conditions, the body releases other chemicals that boost the immune system (for much more, see Chapter 11 in Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections).

 

Weather and wardrobe

 

Will kids get fewer infections if they bundle up in the cold and wear their boots in the rain? Let’s start with the term the “common cold”.  It is not a coincidence that the word “cold” applies to both the weather and the illness – that language linkage exists in many languages besides English. The sniffles are called a “cold” because everyone form the beginning of time knows that colds are more frequent when it’s cold outside. But now there’s science as well as language to support the relationship. In a study done in 2005, 90 volunteers sat with their bare feet in a bucket of ice water for 20 minutes, while another 90 “controls” kept their feet in an empty bucket, still wearing their socks and shoes. Nearly 30% of the cold feet group developed common cold symptoms within the next 5 days, compared to only 9% of the warm-and-dry-footed volunteers. How can this be? How can 20 minutes of an icy foot bath cause 3 times the number of colds? The theory is that we are all occasionally infected with respiratory viruses; oftentimes we don’t get sick because our immune system halts the virus in its tracks.  If, however, we experience a body chilling event while the virus is loitering in our nasal passages, our defenses are temporarily lowered and the virus gets the upper hand, making us sick (for much more, see Chapter 11 in Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections).

 

Exercise

 

The strongest scientific evidence in support of grandma’s wisdom involves the role of exercise in the health of our immune systems. The research has been done in two areas – regular, moderate exercise and extreme exercise (e.g. marathon running). Several well-done clinical trials in adults have shown that daily or almost-daily moderate exercise reduces sick days by half compared with non-exercising adults in the same studies. A large study of nearly 550 adults examined the relationship between physical activity and days of upper respiratory tract infections (the “common cold”). There was nearly a 30% reduction in episodes of respiratory infections in the group with the highest level of regular, moderate physical activity. It’s as if exercising gets our immune systems “in better shape” to respond when challenged by infection, even as exercise gets our muscles and cardiovascular system in better shape to respond to other challenges. But, it’s a whole different story with “extreme” exercisers. In highly active adults, such as elite marathon runners, more than a dozen formal clinical studies have now confirmed that there is a markedly higher rate of upper respiratory infections (the “common cold”) following marathon running (for much more, see Chapter 11 in Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections).

 

Chicken soup and honey

 

Chicken soup has been prescribed by grandma for centuries. In modern times, this wonderful elixir has been given to treat the common cold and the flu. There are several theoretical reasons that chicken soup might help these conditions, but there is no actual scientific proof that chicken soup prevents or treats infections.  Even though we can’t prove grandma right on this one, feed it to your kids whenever they are sick – it tastes great, makes the house smell wonderful, and shows your kids that you love them. Serve it to your kids when they’re not sick, too – same reasons.

 

Over-the-counter cough medicines don’t work in kids and pose a risk for side effects and for accidental overdose (because kids like the taste of some of these products and will drink from an open bottle left in reach). Grandmothers have long known that honey (in tea, in milk, or straight up) makes kids with coughs and colds feel better. A study in 2007 proved that, again, grandma is right. Honey performed better than cough medicine or no treatment at all in easing the cough and helping kids sleep through the cough. (A warning though – honey should not be given to kids under 15 months of age because of the risk of botulism)  (for much more, see Chapter 8 in Germ Proof Your Kids – The Complete Guide to Protecting (without Overprotecting) Your Family from Infections).

 

Conclusion

 

Listen to your grandmother!