Athsma and Rain

Asthma is a chronic condition characterized by
inflammation of the airways in the lungs and by the
spasm of muscles surrounding these airways.
Inflammation occurs when irritated tissues swell
and produce extra mucus, creating a condition
known as bronchoconstriction. The combination of
the two can cause constriction of or complete
blockage of the airways and can initiate symptoms
of an asthma attack.
Allergy plays a key role in about
half of all asthma cases. After exposure to an
allergen, the body releases chemicals that produce
conditions associated with an attack. Common
allergens in the environment are pollen, dust mites,
cockroaches, bacteria, molds, animal hair and
animal dander. Allergens also may originate from
food and food additives.
Exposure to cold, dry air is a common asthma
trigger and can quickly cause severe symptoms.
People with exercise-induced asthma who
participate in winter sports are especially
susceptible. Dry, windy weather can stir up pollen
and mold in the air, leading to problems for some
people.
Hot, humid air also can trigger asthma symptoms,
and wet weather encourages the growth of mold
spores, another asthma trigger. In certain areas,
heat and sunlight combine with pollutants to
create ground-level ozone, which is also an asthma
trigger.
Studies have shown that thunderstorms can
trigger asthma attacks. One study showed that
during thunderstorms, the daily number of
emergency department visits for asthma increased
by 15%. The study concluded that the problem was
caused by the number of fungal spores in the air,
which almost doubled. It wasn't rain, but the wind,
that caused this increase. Changes in barometric
pressure may also be an asthma trigger.