Hay fever has an awful habit of ruining what should be the nicest time of the year. But what is it? And why is it called ‘hay fever’? Kate explores the science of allergies, and hunts through the research for a cure.
KATE MULCAHY: Birch. Ragweed. Timothy grass. Yellow poplar. The usual suspects are out in force. Be prepared for runny noses and sneezing attacks. It's hay fever season.
Okay, let's get something straight first. Hay fever isn't necessarily caused by hay, and usually doesn't bring on a fever. The confusion arose in the 1800s when the condition was first described, and the causes of it were misattributed to the smell of freshly-cut hay.
This may have arisen because hay is usually cut at the same time of year as the symptoms of hay fever begin to strike. It may also be because of an association with a respiratory condition known as farmer's lung, which is caused by inhaling hay dust or mold spores.
The proper term for this condition is allergic rhinitis, which basically means inflammation and irritation of the mucus membranes in the nose.
In order to reach our noses, the pollen needs to be light enough to travel by air. This means we really need to look out for wind pollinated plants, because plants that are pollinated by animals or insects usually have pollen that's too heavy to travel by air.
That still leaves us with plenty of weeds, trees and grasses that can leave your nose a-tingling. In fact, depending on the specificity of your allergy and various pollination times, you could be suffering from hay fever nearly all year around.
The allergic response to pollen is similar to that of other allergens, such as cat hair or peanuts. When a pollen grain first enters your body, it is almost immediately met with a bouncer of your body, the antigen presenting cell. It engulfs the pollen and pushes little bits of it to its own surface. Other immune cells cannot detect foreign invaders, so this step makes it visible to other immune cells, particularly the T cell.
The T cell, in turn, passes the information on to even more immune cells. The most important among these is the B cell.
Upon hearing of an invader, the B cell starts producing large amounts of antibodies called immunoglobulin E. The antibodies swim around in the blood, and attach themselves to yet more immune cells, called mast cells and basophils. When the allergen next enters your body, the antibodies help them stick onto these cells. When this happens, the mast cells and basophils undergo a process called degranulation, where they release large amounts of chemical compounds. These little molecules trigger the dilation of vessels in your nose, and heavy mucus secretion, resulting in a runny nose, sneezing, and congestion.
In a normal immune response, when the invader is actually dangerous, this is a vital step. It essentially lays down the infrastructure so that the rest of the response team can get on location quickly to kill off offending invaders and start repairing the damage.
Unfortunately for hay fever sufferers, scientists don't yet fully understand this. Why do our bodies sometimes perceive harmless substances as harmful, and why do some people's bodies react this way while others don't?
Some scientists have hypothesised it's because our environments are too clean. While others say it's due to pollution, or vitamin D deficiencies in early childhood.
But fear not. You may not need to keep avoiding going outside or pay a tax on summer by forking out for expensive hay fever tablets. Salvation may be on hand thanks to this little fellow.
The idea here is that you could eliminate your allergies by deliberately infecting yourself with parasitic worms. First, you have to swallow the live worms or worm eggs, and then you have them wriggling around inside you. Wonderful!
But there is a solid scientific basis behind this. Parasitic worms, or helmins, actually change our immune system when they infest us, to avoid being detected or acted against.
Recent studies in the use of helmins in the treatment of allergies and other immune mediated diseases has shown a reduction if not an elimination of symptoms.
Now it's important to note that this research is still in its early stages. We're a long way from rolling out wide-scale worm treatments. But, this could be a brave new frontier for not only treatment of allergies, but also diseases such as MS or asthma. And once they figure that out, they can move on to the essential step number 2: figuring out how to make worms significantly less gross.