Paper lays out historical precedents in use of plant based remedies during pandemics

In a historical review published in the journal Frontiers in Plant Sciences​, Spanish researcher Sònia Garcia of the Institut Botànic de Barcelona delved through the evidence of the use of plant remedies in previous pandemics.  It’s a rich history, even for those pandemics that have occurred during the era of modern drugs.

First case: Black Death

The first pandemic with good historical documentation was also the worst: the bubonic plague or the Black Death.  This affliction, caused by the bacterium Yersinia pestis​, raged in Eurasia in 1347 to 1351, killing more than 200 million people and wiping out as much as half the population in some areas of Europe.  But this is just one well documented example.  The so-called Plague of Justinian raged in the Mediterranean region starting in the year 541 and continuing on for as much as 200 years.  Another significant outbreak took place in 1665-1666, and the disease continues on today, including an outbreak in Madagascar in the past decade.  The disease has caused social upheaval, has affected the outcome of wars and has felled empires.

Modern antibiotic therapy has made this a disease which is routinely treated.  In the Middle Ages, an herbal preparation became popular that was known as ‘four thieves vinegar,’ which consisted of a variety of herbs such as angelica (Angelica archangelica​), camphor (Cinnamomum camphora​), cloves (Syzygium aromaticum)​, garlic (Allium sativum), marjoram (Origanum majorana​), meadowsweet (Filipendula ulmaria)​, wormwood (Artemisia absinthium​), and sage (Salvia officinalis​), brewed in vinegar.  Users applied the brew to hands and face before venturing out, in an apparent attempt to prevent infection.  Garcia said some of these herbs acted as flea repellants, while others masked odors or may have relieved pain (meadowsweet, like sweet wormwood, contains salicylic acid, the precursor of aspirin).

Carnivorous plant attacks smallpox

Smallpox is a viral disease that was endemic in European and Asian populations for centuries.  It reached pandemic proportions when it came to the New World and ravaged indigenous peoples who had no resistance. In addition to the toll it took on those peoples, it was reported to have killed more than 300 million people worldwide in the Twentieth Century before being formally declared eradicated in 1980.  Garcia said US Army surgeons and the noted botanist Charles F. Millspaugh detailed the use of poultices and infusions by Native Americans based on Sarracenia purpurea​, a carnivorous plant known as the purple pitcher plant. The preparations from the plant were observed to shrink and dry up the pustules associated with the disease.  It wasn’t until years later that the plant’s antiviral properties were proven in vitro.

Evidence in relation to tuberculosis and malaria

Tuberculosis and malaria are two other ancient disease that continue to afflict the modern world. In the case of tuberculosis, a bacterial disease, Garcia said researchers have been looking for alternatives to standard antibiotic therapies, as drug resistant forms of tuberculosis have started to turn up.  Researchers have been looking to the effects of garlic in these cases, she said.

In the case of malaria, which is a parasitic infection, quinine, derived from the bark of the cinchona tree (Cinchona officinalis​), has been an effective herbal remedy for years. The German government, whose colonial troops in Africa had suffered from not having access to quinine during WW1, embarked on a search for an alternative in the mid 1930s which led to the development of the chloroquinine family of drugs.

Garcia noted, too, that artemisin, derived from sweet wormwood (Artemisia annua​), had been shown to have activity against the malaria parasite.  The compound was ‘rediscovered’ by Chinese researchers who, at the behest of Mao Zedong, were looking for a plant-based alternative to help their allies, the North Vietnamese, during the Vietnam War when malarial outbreaks were thinning their ranks.  

Promise of plant remedies

Garcia said plant-based remedies have been turned to in cases where disease organisms develop a resistance to synthetic therapies. Nevertheless, for medical authorities, plants are still an afterthought.

“There is a human tendency to ignore plants, a form of cognitive bias known as ‘plant blindness’ that should be opposed, perhaps by enhancing and implementing more widely the botanical education. In this context, it is also essential not only to maintain but to increase societal funding into basic sciences such as botany, as well as to foster collaboration between scientists from different disciplines, whose interaction may open new therapeutic possibilities,” ​she concluded.

Source:​ Frontiers in Plant Science​
https://doi.org/10.3389/fpls.2020.571042​
Pandemics and Traditional Plant-Based Remedies. A Historical-Botanical Review in the Era of COVID19​
Author: Sònia Garcia