As students of Hildegard von Bingen, it brings joy to watch her folksy wisdom regain relevance in modern times. While Hildegard lived almost 1,000 years ago, her forward-thinking approach to holistic healing appears less antiquated today. Her wisdom appears in our nascent understanding of seasons and the flu.
Hildegard’s Concept of Balance
Among the primary tenants of Hildegard medicine lies the balance of nature, and in particular, seasons. Like plants in a garden, Hildegard believed in the strong influence of seasons on our health.
While that concept smacks as outdated on the surface, Dr. Victoria Sweet a medical doctor (M.D.) with accompanying PhD in Hildegard Medicine, emphasized the importance of seasons in her book, Rooted in the Earth, Rooted in the Sky.
Pre-modern influence of nature
The forgotten theme of pre-modern medicine includes our close relationship with nature, and a mystic fascination with the number four. According to Dr. Sweet, the number four offers patterns found in nature and helps explain our relationship with the world around us. For example, consider the four elements of earth, air, water and fire; the four qualities of hot, cold, wet, and dry; and the four humors of blood, bile, phlegm, and melancholia.

Today, we still consider the four seasons of spring, summer, autumn, and winter; the four directions of north, south, east, and west; the four ages of childhood, youth, adulthood, and old age; four organs, four temperaments, four colors, and four tastes. According to Dr. Sweet, in totality, these systems bear uncanny resemblances to the great medical systems of the two other pre-modern civilizations of China and India.
Hildegard’s Rule of Fours
Cross-referencing Hildegard’s focus on (i) the four elements (earth, air, water, and fire); (ii) the four qualities (hot, cold, wet, and dry); (iii) the four seasons; and (iv) the four directions brings us closer to understanding her version of four humors, which she called four juices. This was the basis of her convention (subtleties) used to describe the healing properties of herbs, plants, and stones.
Taken together, these concepts bring us to the heart of Hildegard’s brand of holistic healing, found in the greening power of Viriditas. In effect we are the gardeners of our bodies, which are exposed to the external forces of nature. In the abstract, those elements translate into the basics of gardening (air/wind, sun/heat, land/earth, rain/water).
Coronavirus and Seasons
The CDC and medical experts recognize a legitimate hope that the pressure of coronavirus spontaneously lift in advance of identifying a vaccine or cure. Trends show that infection rates of influenza all but disappear in summer months. A close relationship exists between changing seasons and prevalence of the flu.

Infectious disease doctors validate the point, but an explanation for the seasonality of influenza remains less clear. If it were simply a function of temperature, the flu would not exist in areas like Florida during most of the year.
Why is Flu Season in the Winter?
Seasonal factors accounting for flu viruses
With the help of guinea pigs, researchers have demonstrated the phenomenon that flu viruses, like coronavirus spread better in dry cold winter air than in warm and humid conditions. Hildegard used the same terms (dry, cold, wet, warm), which she called subtleties, to inform the effects of healing plants and herbs.
The influence of temperature and humidity remains part of the explanation for the seasonal pattern of flu waves. However, researchers remain unclear on all of the factors influencing the seasonal effect of influenza.
Universal language of seasons
Throughout the world, flu infections occur more frequently from autumn to late winter. The causality of this relationship has not yet been established with certainty. Scientists agree on the presence of several factors to explain the stark contrast of seasonality.

Factors such as changes in the immune system caused in the dark season by the sleep hormone melatonin or a lack of vitamin D, may influence the trend. Scientists also consider the influence of behavioral patterns, such as the propensity for people to spend more time in close quarters during winter.
Environmental factors such as temperature and humidity have long been considered possible influencing factors.
Real tests on guinea pigs
Scientists have now been able to show that the two variables of temperature and humidity play a major role in the spread of droplet infection. A recent Harvard study evaluated the results of tests performed on guinea pigs in the wake of the 1917 Spanish flu pandemic.
Results showed that the guinea pigs were more likely to contract the flu at 5 degrees Celsius than at 20 or 30 degrees. A low air humidity of 20 percent also favored the spread of the viruses, while at air humidities of over 80 percent infections declined to almost zero.
Hildegard’s Subtleties
Hildegard’s principles of subtlety identify inherent healing properties using temperature and moisture. For example, in Hildegard’s medical writings, including Physica, she describes the subtlety of a healing plants. For example, she considered yarrow warm and dry, while her favorite herb, bertram (or “pellitory”) was somewhat warm and dry, and others (like psyllium) were cold. the same factors contribute to the spread of a flu virus.
Cold dry air
Researchers speculate that the dry air dries out the mucous membranes of the respiratory tract, possibly causing minor damage, making it easier for viruses to penetrate. Indications also show that viruses decompose faster in high humidity. In addition, the droplets that transport pathogens remain more finely distributed in dry air than in moist air.

Cold air could also cause nasal mucus to thicken, leaving mucous membranes more vulnerable to infection. In any case, studies showed the animals’ immune system remained largely intact at low temperature.
Scientists now want to use a data comparison to check whether the course of flu waves in humans can be tracked using weather data.
Pre-modern and modern medicine
In her book, God’s Hotel Dr. Victoria Sweet proposes that we’ve lost much of the aggregate wisdom that formed the basis of pre-modern medicine. Our wholesale adoption of modern cellular medicine left us blind to the past. The coronavirus feels like an opportunity for us to begin incorporating historical philosophies with current science.
We talk a lot about the focus of prevention on medieval medical treatments, and the focus on cures in our modern medical system. The unexplained effect of seasonality on our health represents another example of incorporating the extensive knowledge of the past with the present.