For many people that suffer from hay fever, it has been found that there is a certain type of bacteria found in the nasal passages that make hay fever symptoms worse. People with seasonal allergies understand the struggle of the never ending runny and stuffy nose, and these symptoms make the allergy seasons quite unbearable. If doctors are able to target this bacteria that makes these runny nose symptoms worse, this can be a pathway to treat the constant runny nose. 

Hay fever, also known as seasonal allergies, come about when certain allergens such as pollen or mold triggers an inflammatory reaction in the nasal passages. This reaction leads to an overflow of mucus, itchiness and sneezing.Depiction of a person suffering from Allergic Rhinitis

A team of researchers set up a study in which they analyzed the microbial population in the nose of people who have hay fever and those who do not. After examining the noses of these patients they found that the people that had hay fever had little diversity in the nasal biome as opposed to the non-hay fever patients. It was actually found that there was an abundance of a particular species of bacteria called streptococcus salivarius in the patients who had hay fever. In fact, the S. salivarius bacteria was found to be 17 times more abundant in the nose of people with allergies compared to those without. This major difference in the amount of  S. salivarius bacteria plays a major role in arousing allergy symptoms. To further understand the role that the S. salivarius bacteria plays in provoking allergy symptoms, an experiment was conducted where researchers studied allergen-exposed cells that line airways. And in examining these allergen-exposed cells, they found that the S. salivarius boosted the cells’ production of inflammation promoting proteins. Due to the fact that hay fever is an inflammatory reaction and this bacteria helps produce inflammatory promoting protein, it exposes the link between hay fever and the S, salivarius bacteria. A common symptom of hay fever is the overproduction of nasal discharge, and it was found that S. salivarus is good at binding to airway-lining cells that are exposed to allergen cells covered in mucus, which therefore produces more mucus. Furthermore, the binding of the S. salivarius bacteria and the air-way lining cells is the major factor in why this bacteria worsens the effects of hay fever.

Streptococcus salivarius

 Now, with this research in mind, the next step is to discover how to specifically target this bacteria to help lessen the effects of hay fever. Researchers are now finding a way to find methods that block the adhesion of the S. salivarius bacteria to the allergen exposed cell. Hopefully they come up with a method in the near future because that will for sure make the spring season more pleasurable for me!

Connection to AP Biology 😀

This connects to our AP biology class as we went into depth about our immune systems and their different defense mechanisms. Our immune system protects the body against pathogens such as viruses and bacteria. In our biology class, we learned about 2 different immunity systems: innate and adaptive immunity. In this blog, inflammation and overflow of mucus are recurring topics as they are the main symptoms of hay fever. These responses come from our innate immunity which is a defense that is an immediate reaction upon infection. This reaction is nonspecific and it is a rapid response. when a pathogen can go beyond the barrier defenses, such as your skin, that is when the innate cellular defense is triggered. Most of these triggers lead to an inflammatory response. So, with this in mind, it is clear that after pollen gets past an individual with hay fever skin barrier, that triggers the innate cellular defense which then results in inflammation and an overproduction of mucus.