Allergies affect a large number of people worldwide and so governments and pharmaceutical companies spend billions of research dollars each year in an effort to better diagnose and treat them. Below is an overview of some of the recent medical developments in allergy research and some links to recent scientific and news articles about allergies.
Early exposure to allergens
Pet exposure
Several studies provide evidence that young children who are raised in a home with two or more dogs and cats are less likely to develop allergies both to animal dander and to several other types of airborne allergens. Scientists are unsure why this early exposure seems to protect some children from developing later allergies but some evidence suggests that it may have nothing to do with exposure to pet dander. Instead, some scientists believe that exposure at a young age to bacteria carried by pets but not by humans may cause the human immune system to shift away from developing allergies. A bacterial protein called endotoxin seems to cause the human immune system to make a large quantity of a type of cells called Th-2 cells, which block allergic reactions from taking place. More research is needed to determine how this can be used for better treatments.
Breastfeeding
Some studies indicate that breastfeeding a baby leads to lower incidences of allergies, while others have failed to find this effect. The American Academy of Pediatrics policy statement recommends breastfeeding a child for at least the first four months of life to delay and prevent the development of food allergies. So far, the effect of breastfeeding has only been conclusively shown for babies with a high risk of developing allergies. Breast milk contains antibodies and other immune system molecules that may help prevent allergic reactions from occurring, or it may be that small amounts of allergens from the mother’s diet pass to the nursing baby, somehow causing tolerance. Several other health benefits of breast milk have been established and so breastfeeding is the preferred method of nutrition for the overall health of any baby.
Delayed exposure to allergenic foods
In the past, doctors thought that controlling a child’s exposure to potential food allergens might delay or even prevent the development of allergies. However, the most recent guidelines from the American Academy of Pediatrics reject this view, stating that there is not enough evidence to support the claim that waiting to give kids certain foods has any effect on their development of allergies. Earlier guidelines had suggested delaying a child’s exposure to cow’s milk until after their first birthday, eggs until age two, and peanuts, tree nuts, and fish until age three. There also appears to be no effect of the mother’s diet during pregnancy on subsequent allergy development. Talk to your doctor if you want to learn more about this ongoing research.
Genetics of allergies
While it is known that genetics play an important role in the development of allergies, exactly which genes are involved is still a mystery. Scientists are using new techniques of genetic analysis to study families that have many allergy sufferers in search of the genes that are shared by those affected but not by those who aren’t. So far, they have identified several candidate genes but none has been shown conclusively to cause allergic reactions. Not surprisingly, most of candidate genes are ones that are involved in the immune response.
Allergy treatments
Scientists continue to seek better ways to treat allergies. Much of this work is concentrated on understanding the factors involved in producing IgE antibodies, the immune system molecule that starts an allergic reaction. Other research avenues are trying to manipulate the cells and molecules involved in the immune response (e.g. histamine) in order to prevent or lessen the impact of allergic reactions.
Epidemiology of allergies
In addition to studying the genetic factors that cause allergies, several researchers are examining the epidemiology of allergies. Epidemiology looks at who gets allergies and when, which allows scientists to see broad trends in allergy diagnosis. This type of information can help research agencies decide what types of studies to fund and can provide the impetus for a public awareness campaign. For example, recent studies indicate that more children are being diagnosed with peanut allergies than ever before. This is important information for people such as new mothers, even if we don’t yet know why this increase is occurring.
Links to recent allergy developments
Allergy news on Science Daily, a digest of recent science research news.
http://www.sciencedaily.com/news/health_medicine/allergy/
PubMed is a U.S. National Institutes of Health search engine that covers all research published in medical and bio-scientific journals.
http://www.ncbi.nlm.nih.gov/PubMed/
PubMed Central is the National Institutes of Health’s digital archive of biomedical and life sciences journal literature.
http://www.pubmedcentral.nih.gov/
The U.S. Food and Drug Administration Center for Biologics Evaluation and Research is the government agency charged with reviewing and approving applications for new drugs and medical devices and their website has information about recent developments in these areas.
http://www.fda.gov/Cber/index.html
Information about clinical trials
If you are interested in finding out more about clinical trials for allergies, the National Institutes of Health has a clinical trials website at http://clinicaltrials.gov/.
To find a clinical trial being conducted in your area, visit the Healia Clinical Trials Search page.