The effectiveness of a standardised Echinacea preparation in preventing colds, flus and other respiratory disorders for air-travellers

Air travel, especially on intercontinental flights can be stressful. Studies have shown that passengers' well-being is influenced by the cabin environment such as quality of cabin air, oxygen pressure in the cabin, motion or vibration and oil additives used in aircraft engines [1, 2]. Various studies have reported and investigated the occurrence of nasal dryness [3] and the increased risk of developing upper respiratory disorders such as allergic rhinitis [4] and attracting virus or bacteria induced respiratory infections [5, 6]. Studies have shown that Echinacea, one of the most widely used herbal medicines worldwide, can decrease the severity of cold symptoms and improve quality of life if used as early treatment [7-9]. Some studies also suggest positive effects for the prevention of the common cold when using Echinacea [8]. Here we report on a randomised, double-blind placebo controlled clinical trial with 183 participants who were travelling return from Australia to America, Europe or Africa for a period of 1-5 weeks on non-stop commercial flights via economy class. Participants were using coated Echinacea (standardised to 4.42mg alkylamides) or placebo tablets, and trial dosing consisted of three protocols (priming, travel and sick), depending on the phase of travel of the participants and their health status. Outcomes were assessed using a survey which included questions about upper respiratory symptoms (based on WURSS-44), quality of life (based on SF-36) and the occurrence of additional air travel related symptoms. Each participant completed this survey before travel (baseline), after travel (return) and at 4 weeks after return from travel (follow-up). Preliminary results so far indicate that at follow-up a significantly lower number of participants reported respiratory illness in the Echinacea treated group compared to placebo (P=0.02) and a significantly higher number of participants treated with Echinacea reported a 䧯od" quality of life compared to placebo (P=0.005). Moreover, a significantly higher number of participants in the placebo group compared to the Echinacea group reported respiratory illness at follow-up compared to baseline (P=0.044) suggesting that the placebo group had not returned to the pre-travel level in terms of respiratory illness.