Their Best Shot –

In the epidemic growth of allergies, the environment seems to play a larger role than researchers first thought. New studies into immunotherapy are giving sufferers…their best shot.

Health Correspondent Stacey Singer reported in the SUN SENTINEL the story of a 2-year old by the name of Grace King. At birthday parties, this sociable girl sometimes leaves before the cake is served. That is because Grace is allergic to both milk and eggs, and cake and ice cream could send her to the hospital.

One third to 50% of the population has some sort of allergy, and the severity of allergic reactions appears to be growing quickly, especially in children. As an example, the number of children who react to peanuts tripled between 1989 and 2002, according to a recent European study. The same trend is emerging for many other allergies.

The quest to understand the cause of allergies has taken scientists from farm fields to inner cities, from laboratories to grocery stores. The allergic response remains full of paradox: Filth can cause disease and asthma. Yet new studies suggest clean living probably unleashes allergies.

It is hard to imagine that Grace King’s clean house or suburban lifestyle could have unleashed Grace’s severe food allergy, but a concept known as the “hygiene hypothesis” has gained converts.

The thinking is that clean food and water and indoor living have deprived us of exposure to germs and parasites that our great-grandparents survived. As a result, our immune systems never get trained properly. Dr Marc Rothenberg, chief of Allergy and Clinical Immunology for the Cincinnati Children’s Hospital, refers to it as the immune system’s “delinquency problem.” “The immune system has too much free time, and it is getting into things that it shouldn’t,” he said.

This theory has gained support from a New England Journal of Medicine Study. Trying to understand why farm children were less likely to have allergies, researchers found that farm children’s mattresses were covered with bacteria endotoxin, the kind found in farm animal manure. Day and night, those children were breathing, touching eating, and drinking germs, and they appeared to have healthier immune systems as a result, according to Dr. Scott Weiss of the Channing Laboratory at Harvard University.

There are other theories. A French scientist showed that as measles and whooping cough have declined, while allergy, asthma and autoimmune diseases have risen. Childhood vaccines have also been implicated, he wrote in the New England Journal of Medicine. There may be a type of immune response mobilized by the shots, and these have an effect on the evolution of a child’s immunity.

This scientist also raised the possibility that babies who take antibiotics could also have problems because of the way the drugs alter intestinal flora, a key component of the immune system. One study showed that pregnant women with allergies that were given large doses of lactobacillis, commonly found in yogurt culture, had newborns with significantly less eczema.

Other research suggests that environmental pollutants may act like lighter fluid on a grill. While they may not cause allergy, they may prompt allergies to burn hotter. Things like truck exhaust, second-hand cigarette smoke, and flame retarding chemicals used in computer monitors have all shown some ability to heighten sensitivity of people to allergens in laboratory studies, according to Reuters Health.

Western diets have also been implicated. Weiss, at Harvard is studying the role of fats and oils in pregnant women’s diets. Some suspect that omega-3 fatty acids may help, while trans fats, widely used by fast-food makers, might worsen allergies and asthma.

On the prevention side, evidence is mounting that going to an allergist for a monthly allergy shot works well for treating inhaled allergies and insect-venom allergies, and can prevent new allergies and asthma, especially in children. Two recent studies showed that the shots prevented allergies from growing into asthma in a significant percentage of allergic children.

Other preventive strategies have been scrutinized. The American Academy of Asthma, Allergy and Immunology recommends that parents with allergies introduce new foods to their infants very slowly. Breast-feeding exclusively for the first six months is preferred, the group recommends.

For Grace King, the severely allergic 2-year old, the best approach at this point is to avoid the offending foods, and keep a loaded syringe of epinephrine on hand at all times.

(Summarized from SUN-SENTINEL, Ft. Lauderdale, Fl. , Feb. 2003)