Harvard Medical School reports that the number of New Yorkers seeking hospital treatment for asthma symptoms doubled in the last week compared with the first three weeks of April. According to the Associated Press, sales of over-the-counter allergy medications also increased more than twofold in two weeks. Both trends signal the start of the spring allergy season, and the asthma attacks it can trigger, health officials said.

In the United States, more than 50% of people test positive for one or more allergens. Twenty years ago, only 30% tested positive. Some surveys suggest an even more dramatic increase. Trends for allergies and asthma are similar in Western Europe, with a two-fold rise during the last couple of decades.

There are several theories as to why allergy and asthma cases continue to rapidly increase:

• Modern Pollution.
• Introducing certain highly allergic foods, such as peanuts, too early in a child's life.
• Waiting too long to expose young children to peanuts.
• Early exposure to pets.
• Not having pets in the house. Children born when pets are already in the house or children who live on farms appear less likely to be allergic.
• The ‘Hygiene Hypothesis.’ We are using so many ant-infective products, including antibiotics, drugs for parasites and fungi, and antibacterial soaps, that our immune systems do not get a chance to regulate properly. Instead, our immune system is primed to react to what in the past would have been just another allergen. Now it overreacts.

The more popular theories today are the ones suggesting that early life exposure to allergens such as pets and maybe even peanuts will protect against having allergic and asthmatic symptoms later.

The rising prevalence of asthma in inner cities is very worrisome to public health officials. Too many children and adults are missing school and work, and the death rate from asthma has remained at an unacceptable level.