Seasonal allergy is an allergic reaction to a trigger that is typically only present for part of the year, such as spring or fall. This type of allergy refers to a pollen allergy, such as trees, weeds and grasses. Symptoms include sneezing, runny nose, nasal congestion, itching of the nose, and post-nasal drip. Not all people experience all of the symptoms and in some, only one symptom will predominate. Sometimes it may be difficult to tell the difference between seasonal allergies and the common cold, and only an allergist may be able to tell the difference.
 
There is Spring Allergy, Summer Allergy and Fall Allergy and they are all caused by a different pollen type.

Ticks are blood-feeding parasites that are often found in tall grass where they will wait to attach to a passing host. Ticks are not insects, but arachnids that differ from the insect form and other biological properties. They feed on the blood of animals and humans and can transmit many infectious diseases, including those that are common to humans and animals. It is not the tick bite but the toxins, secretions, or organisms in the tick's saliva transmitted through the bite that causes disease. Ticks tend to attach and feed for hours to days. Disease transmission usually occurs near the end of a meal, as the tick becomes full of blood.

Small amounts of UV radiation are beneficial to health, and play an essential role in the production of vitamin D. Vitamin D strengthens the bone and musculoskeletal system. However, excessive exposure to UV radiation is associated with different types of skin cancer, sunburn, accelerated skin ageing and some eye diseases. There is also evidence that UV radiation reduces the effectiveness of the immune system.
 
Between 50% and 90% of skin cancers are due to UV radiation. In 2000, there were 200 000 cases of melanoma and 65 000 melanoma-associated deaths worldwide.

Children and adolescents are particularly vulnerable to the harmful effects of UV radiation. Excessive sun exposure in children is likely to contribute to skin cancer in later life. Fair-skinned people suffer more from sunburn and have a higher risk of skin cancer than dark-skinned people. However, even though the incidence of skin cancer is lower in dark-skinned people, the cancers are often detected at a later, more dangerous stage. The risk of eye damage, premature ageing of the skin and immunosuppression is independent of skin type.