Germs protect against allergies

Contact with germs can reduce the risk of allergies

06/21/2013

Almost one third of adults in Germany have already suffered from an allergy once in their lives. This is shown by a new study by the Robert Koch Institute (RKI). One of the most commonly diagnosed allergies is hay fever. But also food and insect venom allergies occur increasingly. Researchers suggest that early contact with germs could protect against future allergies.

Allergies limit the quality of life
Itchy rash and pustules, watery eyes, a runny nose and shortness of breath are just some of the symptoms that may indicate an allergy. In the worst case, a so-called anaphylactic shock can occur, which can lead to cardiovascular shock and organ failure. If the person is not treated promptly, he or she may die from the allergic reaction. For most people, however, the allergies are much weaker. Nevertheless, allergies can severely limit the quality of life by not only affecting social life but also reducing performance and work ability. While food allergies are often easy to manage by eliminating the consumption of certain foods, such as lactose intolerance, the elimination of cow's milk products, people with hay fever have little ability to escape the allergenic pollen. In most cases, only medications with sometimes severe side effects or a special procedure for hyposensitization are available. Some natural remedies can relieve the symptoms, but not cure. That is why doctors and scientists are feverishly searching for new solutions that prevent allergies in advance.

Incidence of allergies is increasing
Since the 1970s, allergies in western industrialized countries have increased dramatically. Nobody knows yet how this development came about. An explanation could be found in the western lifestyle. This is also supported by the development of allergies in East Germany. Shortly after reunification in the early 1990s, there were far fewer allergies in the new federal states despite the heavy air pollution than in the West. Meanwhile, both the lifestyle and the frequency of allergies have adapted.

Against the background that allergies have become one „widespread disease“ developed, the RKI led to an investigation „Incidence of allergic diseases in Germany. Results of the study on adult health in Germany“ by. According to this, almost one third of adults in Germany have been diagnosed with an allergy once in their lifetime. „Currently, nearly 20 percent suffer from at least one allergy“, write the authors. Those affected have allergies to plant pollen, mites, pet dander, insect venom or foods such as nuts or eggs and dairy products. However, the majority of allergy sufferers (14.8 percent) are affected by hay fever. „Women are generally more affected than men and younger people more often than older people“, summarize the authors of the RKI study. Overall, the sum of all allergic disease since 1998 but decreased. „However, a closer look at the development over time shows that the incidence of bronchial asthma has continued to increase, thus continuing the trend of the 1970s to the 1990s, but the incidence of hay fever, atopic dermatitis and food allergies has remained the same, thus reaching a plateau seems to have“, it says further in the investigation. The researchers point out, however, that the apparent decrease in allergic diseases is controlled by the lower number of physician diagnoses in urticaria (hives) and contact dermatitis. On the one hand, it is conceivable that the number of illnesses actually decreased, on the other hand, however, the use of allergenic substances such as nickel or henna to dye hair in everyday life has been restricted. In general, the effect of these substances in the public would be discussed more. In addition, however, another factor could have led to the decrease in medical diagnoses. „For example, ointments and creams containing corticosteroids have been exempted from prescription, so that a possible self-treatment of mild allergic skin diseases could lead to fewer visits to the doctor“, the researchers write.

Many children affected by allergies
More than 20 percent of children are affected by an allergy at least once. This is especially worrisome, because the risk of life-threatening allergic reactions in children is increased sevenfold, reports Sonja Lämmel from the German Allergy and Asthma Association to the news agency „dpa“.

Allergies occur when the immune system shows violent defense reactions in actually innocuous substances. „One has to imagine the immune system of allergy sufferers as a hyperactive police force that reduces crime. But with the disadvantage that sometimes it also imprisons innocent people, "explains Torsten Zuberbier, head of the European Foundation for Allergy Research and spokesman for the Allergy Center of the Berlin Charité, told the news agency.

New therapeutic approaches against allergies
Ten years ago, the Marburg allergist Harald Renz and his team discovered why farm children are much less likely to suffer from allergies. Their risk of asthma or hay fever is only half that of children growing up in urban settings. „It's not the pigs or cows themselves that have the positive effect, "Renz told the news agency. „These are the microbes that occur in large numbers on such farms. "These turn off the genes that trigger allergic reactions, and Renz suspects that early contact with many bacteria will harden the immune system, so that infants may receive targeted treatment with germs for prevention. „If we can figure out how these microbes manage to eliminate certain genes, we can target them for preventative treatment. "The bacteria could then have a positive effect on the intestinal flora while preventing allergies.

The allergist conducted experiments on mice in which pregnant mice sucked in special bacteria. As a result, the animals were less likely to suffer from allergies. Since the preventive approach is not yet mature, further studies need to be carried out, especially with regard to the transferability to humans. There have already been many attempts with intestinal germs, which also partially reduced the risk of allergies. „However, we do not yet know exactly how they will work, "says Renz, and the timing of the ideal start of therapy is not yet clear, for example, the treatment could be started as early as during pregnancy or as early as the baby's infancy.

„There is an experimental research approach, a vaccine with bacterial components. In doing so one tries to train the immune system of infants better ", Lämmel explains with reference to food allergies. „Current prevention recommendations suggest that the mother breast-feeds for four to six months, and that infants are then offered all food as part of the complementary diet. So also cow's milk and fish, so that the immune system can develop tolerance early. "

To prevent allergies, preventive approaches gave hope, says Renz. „They mean the chance to prevent allergies already before they even plague the patients. "Until then, those affected usually only the renunciation of allergenic substances and a drug therapy to relieve their symptoms.