Echinacea (Echinacea angustifolia, purpurea, pallida) is a popular herb its name coming from the Greek word for sea urchin, referring to its spikey seed head. This valuable herb is used for stimulating the immune system, its use dating back to the Nineteenth century American eclectic schools of herbal medicine who learned it from the American Indians. The dried herb is widely available in the supermarket in the form of a compressed pill, often combined with other respiratory system herbs, vitamin C and zinc, and is mostly used for preventing or treating colds and flus.^1,2

We think of Echinacea as an antimicrobial, antiviral and anti-inflammatory agent, whereas the Indians were known to use it for treating septic conditions such as snakebite. In fact, the old herbalists considered it a powerful antiseptic agent capable of detoxifying the blood and even stopping gangrene, so that it found uses as varied as treating boils, abscesses, eczema, candida, appendicitis, meningitis, rabies, syphilis and puerperal fever.³

In herbalism today we call it an immune modulator which means that it contains phytochemical substances which can exert a stimulatory or inhibitory influence over different parts of the immune system. These effects include an increase in complement, IgM, macrophage activity, interferon and natural killer cells, as well as displaying antiviral and anti-inflammatory activity.

We can take it broadly to boost a flagging immune system or directly treat colds, flus, sore throats, bronchitis, pneumonia, tonsillitis, dysentery, candidiasis, hepatitis, cystitis and so on. The tincture or infusion can also be applied externally to infected wounds, abscesses, ulcers and bites in order to curtail infection. It is a safe herb when used long-term as well as during pregnancy.

The pressing issue today is whether or not there is any evidence that Echinacea can help prevent or treat the virus SARS-Cov-2 which causes COVID-19. In fact, the evidence-base suggests that Echinacea can help limit the severity of symptoms as well as the progression of the disease and therefore have an important role to play, along with other herbs and nutrients, in treating this virus and its after-effects (post-COVID).⁴

COVID-19 is easily acquired from micro-droplets exhaled by an infected person or by touching objects or surfaces covered in viral particles. The virus targets bronchial epithelial and alveolar cells through ACE2 receptors, causing acute inflammation of the lung and massive viral cell production, which in turn may cause severe acute respiratory distress syndrome (ARDS) or pneumonia. In severe cases the immune system is seriously dysregulated as evidenced by an excessive rise of pro-inflammatory cytokines, known as a ‘cytokine storm’, often requiring intubation and artificial ventilation. The virus can spread to the blood (viremia) and multiple organ system dysfunction or failure may follow due to the widespread distribution of ACE2 receptors on many different types of tissues in the body (heart, kidney, blood vessels, liver, pancreas, gut, thyroid).

A general inflammatory response of this type is usually followed by an adaptive response with T-cells and B-cells which more specifically targets the virus with antibodies. These antibodies then block viral attachment to ACE2 receptors on host cells. This is also the purpose of vaccination, a strategy which has so far proved highly effective in limiting the severity of illness and the possibility of hospital stays; however, it does not prevent infection or transmission amongst vaccinated individuals.

Apart from vaccines, the most effective class of medicines in treatment so far are anti-inflammatory drugs (dexamethasone), while new antivirals (remdesivir, ritonavir, molnupiravir, molnupiravir) and immune modulators (chloroquine, ivermectin) are constantly being tested as a second line of treatment. The purpose of these drugs is to limit complications and mortality by attenuating the cytokine storm and viral replication, just as is the case with herbal medicines and clinical nutrients.

To this end Echinacea broadly affects immune system cells including dendritic cells, monocytes, macrophages, natural killer cells and T-cells. As an anti-inflammatory agent, Echinacea inhibits interleukins (2, 6) as well as tumour necrosis factor (TNF-a). Interleukin 6 (IL-6) is of particular interest because elevation is a feature of the cytokine storm which causes lung injury in COVID patients. In fact, the drug tocilizumab has demonstrated effectiveness by inhibiting Il-6, albeit with several serious side-effects. Echinacea also modulates both systemic and local immune activity through CD4+, CD8+, T-cells and pro-inflammatory cytokines.⁵

Inflammation also causes oxidative stress which further contributes to tissue and organ damage in advanced cases of sepsis. Importantly, Echinacea displays potent anti-oxidant and free radical scavenging activity, a function  attributed to phenolic compounds. These activities show the potential of Echinacea to protect organs other than the lung such as the liver, intestines and heart, helping to prevent sepsis and multi-organ failure during dysregulated inflammatory activity. There are, however, differences in the constituent profile and activity of the three species used, as well as the potency of the root, leaf or whole-plant products.^6,7

As an antiviral, Echinacea has demonstrated effectiveness against coronaviruses (MERS-CoV, SARS-CoV-1, SARS-CoV-2) as well as rhinoviruses, adenoviruses, influenza and herpes. The mechanism of the herb’s non-specific antiviral response are several: the inducement of phagocytic immune cells by influencing pathogen-associated signalling pathways upon viral entry into cells (PRR, PAMP, DAMP); the constituent chicoric acid displays antiviral activity; also the expression of adhesion molecules in the bronchial epithelium, exploited during infection by viral cells, is inhibited.^5,8

Echinacea certainly holds promise for protection from contagion or during treatment of an active respiratory infection by COVID-19. This protection is enhanced with the regular consumption of other synergistic immune system herbs and nutrients such as zinc, vitamin C, vitamin A, quercetin, garlic, curcumin and cod liver oil. Compared to modern experimental drugs and vaccines which have unfortunately required curtailed approval processes (most recent in Australia is molnupiravir ordered by the government before TGA approval) for a rollout that actually constitutes a vast clinical trial, all of the above alternative medicines have an extensive evidence base as well as a reliable traditional usage that testifies to their relative safety and freedom from side-effects.

This Article appears in the 2021 eBook edition of Wholefoods And Common medicinal Herbs.

Disclaimer:

This article is intended for the purpose of general education only, and is not a substitute for a diagnosis, treatment advice, or a prescription given in a consultation with a qualified physician.

References:

1.         Aucoin M, Cooley K, Saunders PR, et al. The effect of Echinacea spp. on the prevention or treatment of COVID-19 and other respiratory tract infections in humans: A rapid review. Adv Integr Med 2020;7:203–17.

2.         Ogal M, Johnston SL, Klein P, Schoop R. Echinacea reduces antibiotic usage in children through respiratory tract infection prevention: a randomized, blinded, controlled clinical trial. Eur J Med Res 2021;26:33.

3.         Boericke W. Pocket Manual Of Homoeopathic Materia Medica, c. 1927. Delhi: Indian Books & Periodical Publishers; 2007.

4.         Keflie TS, Biesalski HK. Micronutrients and bioactive substances: Their potential roles in combating COVID-19. Nutrition 2021;84:111103.

5.         Nagoor Meeran MF, Javed H, Sharma C, et al. Can Echinacea be a potential candidate to target immunity, inflammation, and infection – The trinity of coronavirus disease 2019. Heliyon 2021;7:e05990.

6.         Aarland RC, Bañuelos-Hernández AE, Fragoso-Serrano M, et al. Studies on phytochemical, antioxidant, anti-inflammatory, hypoglycaemic and antiproliferative activities of Echinacea purpurea and Echinacea angustifolia extracts. Pharm Biol 2017;55:649–56.

7.         Barnes J, Anderson LA, Gibbons S, Phillipson JD. Echinacea species (Echinacea angustifolia (DC.) Hell., Echinacea pallida (Nutt.) Nutt.,Echinacea purpurea (L.) Moench): a review of their chemistry, pharmacology and clinical properties. J Pharm Pharmacol 2005;57:929–54.

8.         Signer J, Jonsdottir HR, Albrich WC, et al. In vitro virucidal activity of Echinaforce®, an Echinacea purpurea preparation, against coronaviruses, including common cold coronavirus 229E and SARS-CoV-2. Virol J 2020;17:136.