Updated: Jul 6, 2020
On March 11, 2020, the World Health Organization (WHO) declared a pandemic caused by SARS-CoV-2 a virus and the disease it causes: COVID-19.
There are seven known coronaviruses that infect humans, including four that are responsible for about 15% of common colds. The four “cold” coronaviruses affect the upper respiratory tract and cause symptoms such as the sore throat or runny nose.
Three coronaviruses have caused major human disease: SARS-CoV, MERS-CoV, and SARS-CoV-2 virus, or “the novel coronavirus” as it’s commonly called. These three affect the lower respiratory tract – the lungs. It is unclear whether SARS-CoV, MERS-CoV, or SARS-CoV-2 could also affect the upper respiratory tract (Yang et al 2020).
SARS-CoV and MERS-CoV were the cause of two major outbreaks in the last two decades in South East Asia and the Middle East. We can look at these past epidemics to understand how other coronaviruses behaved, and how we managed their spread.
SARS-CoV was first identified in China in 2002, and it spread to more than 30 countries. In the 2002/2003 outbreak, SARS-CoV had about a 10% fatality rate. The intermediate source was civet cats sold in a live meat market, which had been infected by horseshoe bats acting as SARS-CoV reservoirs (Tessini 2018, Luk et al 2019). About 8,000 people were infected in the outbreak, with less than 800 fatalities across 11 countries (Luk et al 2019).
The MERS-CoV outbreak occurred in 2012, and all cases were people linked to residence or travel through the Middle East, with >80% in Saudi Arabia. The median age of MERS-CoV infected people was 56yo, and it was more severe in elderly patients and those with pre-existing conditions. MERS-CoV is spread through direct contact, respiratory droplets, and aerosols. The intermediate carrier is likely dromedary camels, but the mechanism of transmission to humans is unknown. The fatality rate is about 35%, and in about 21% of infected people, there are mild or no symptoms. The 2012 outbreak was contained early, with a total of 2,494 infected people, but a small number of cases still occur each year (WHO).
The novel coronavirus is officially called SARS-CoV-2, and the resulting disease is called COVID-19. The name was picked by the WHO and is an abbreviation for coronavirus disease. SARS-CoV-2 is spread via large respiratory droplets but might spread via fecal-oral routes, surfaces infected by respiratory droplets, and aerosols. It is important to note that COVID-19 fatality rates are still unclear, as they fluctuate from country to country and currently range from 0.9% in South Korea to 7% in Italy, but fatality rates are heavily influenced by the amount of testing performed. With the focus currently on very ill patients, it is impossible to accurately determine how many people are infected because many may show mild symptoms but are not tested. The elderly and people with pre-existing conditions, such as heart disease or respiratory disease, are more likely to experience severe symptoms and have a higher risk of dying.
At the time of writing this article, there is no known cure for COVID-19, and there is currently no research into the effect essential oils may have on this particular virus.
Essential oils considered to be “antiviral” are not universal virus killers. In many instances, essential oils may be effective in killing one specific virus, but not another. Tea tree (Melaleuca alternifolia) essential oil inhibits the proliferation of influenza viruses inside cells (making it antiviral), but only modestly inhibits HSV-1 and HSV-2 (Garozzo et al 2009). In addition, finding research for antiviral activity does not equate to finding an “essential oil recipe for the virus”.
Because there is no known cure for COVID-19, medical interventions focus on symptom management, and in severe cases necessitate respiratory support via ventilators. Under no circumstances should you try to address a severe case of the disease, and once shortness of breath occurs, you must seek medical help immediately. If only mild symptoms are present, you could use essential oils to assist in their alleviation – chest rubs containing pinene or cineole rich essential oils such as Eucalyptus (Eucalyptus globulus) or Rosemary (Rosmarinus officinalis), steam inhalation with the same oils, etc. You could also use inhalation to combat the inevitable stress and anxiety. The use of lavender (Lavandula angustifolia) essential oil with citrus essential oils, often sweet orange (Citrus sinensis) or lemon (Citrus limon), has been effective in reducing situational anxiety, as well as chronic anxiety (Lehrner et al 2005, Perry and Perry 2006, Goes et al 2012).
By far the best thing you can do to mitigate the pandemic is to follow the recommendations of the WHO and other public health authorities – social distancing and hand hygiene.
While claims that essential oils will help protect you from, or treat COVID-19 are not based on evidence, this does not mean you cannot or should not make use of essential oils for respiratory and psychological support.
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