In some rural areas there is another form of seasonal grass allergy, combining airborne particles of pollen mixed with mold.
Recent research has suggested that humans might develop allergies as a defense to fight off parasites.
Seasonal allergy symptoms are commonly experienced part of the year, usually during spring, summer or fall when certain trees or grasses pollinate. For instance, some trees such as oak, elm, and maple pollinate in the spring, while grasses such as Bermuda, timothy and orchard pollinate in the summer.
Grass allergy is generally linked to hay fever because their symptoms and causes are somehow similar to each other.
These allergen antibodies migrate to mast cells lining the nose, eyes and lungs.
When an allergen drifts into the nose more than once, mast cells release a slew of chemicals or histamines that irritate and inflame the moist membranes lining the nose and produce the symptoms of an allergic reaction: scratchy throat, itching, sneezing and watery eyes.
Other common causes of serious allergy are wasp, fire ant and bee stings, penicillin, and latex.
According to Yale University Immunologist Dr Ruslan Medzhitov, protease allergens cleave the same sensor proteins that evolved to detect proteases produced by the parasitic worms.
Additionally, a new report on seasonal allergies called “Extreme allergies and Global Warming”, have found that many allergy triggers are worsening due to climate change.
Indeed, seasonal allergies are one of the main triggers for asthma, along with colds or flu, cigarette smoke and exercise.
In Canada, for example, up to 75% of asthmatics also have seasonal allergies.