“Don't just rely on the textbook definition of when the pollen seasons are. You need to have reliable data to know when the pollen seasons are starting, when they're ending, and when they're peaking.”  Dawn Jurgens

Allergy season may be winding down, but for allergists, the work never really stops. This is the moment between ragweed and winter — a brief respite before the cycle begins again. On this episode, Dr. Mariam Hanna is joined by Dawn Jurgens, Director of Operations and Quality Management at Aerobiology Research Laboratories. She breaks down the science behind pollen and spore counts, why forecasts matter, and how shifting seasons are changing the game for patients and clinicians alike.

• Timothy grass is the most common and potent trigger globally, while birch remains the most clinically relevant pollen in Canada. Pine releases large amounts of pollen but isn’t highly allergenic.
  
  
• Pollution and thunderstorms can make pollen more potent by breaking it apart and exposing allergenic epitopes, intensifying symptoms.
  
  
• Cross-reactivity stems from conserved epitopes, meaning patients sensitized to one pollen may react to related species — or even certain foods.
  
  
• Mold spores, especially Alternaria, Cladosporium, and Basidiospores, can mimic ragweed season and are major fall culprits.
  
  
• Canada’s pollen seasons are starting earlier than they did 30 years ago, though the fall season hasn’t yet extended.
  
  
• Simple strategies — like showering before bed, keeping windows closed, using filters, brushing pets outside, and checking reliable forecasts — can meaningfully reduce exposure.

Pollen season may be taking a break, but planning for the next wave starts now.

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The Allergist is produced for CSACI by PodCraft Productions