Affiliations : Barts and The London School of Medicine and Dentistry
Journal reference: doi.org/10.1038/s41415-020-1545-3
Summary: Since the COVID19 pandemic scientists have been scrambling to find out more about how this virus works. In this fascinating article Dr. Sampson details the connection between oral health and COVID19. After all, who would have thought that flossing might help save your life?
Unbeknownst to the majority of the population, there is a huge connection between the mouth and the rest of your body. So much so, it is thought that the mouth is the mirror to one’s health and merely an extension of your gut. The connection is mutual. If the mouth is in bad shape, this can impact the rest of the body by manifesting into illnesses such as heart disease, diabetes, high blood pressure, and dementia just to mention a few. In recent years, oral hygiene and dental health have been added as risk factors for developing chronic diseases and the connection between them has been well established. On the other hand, if the body is in bad shape, dentists can see this in the mouth. For example, the mouth often reacts to inflammation and nutritional deficiencies through gum disease, dry mouth, inflammation, ulceration and increased frequency of decay. When we take certain medications or undergo hormonal changes such as pregnancy or puberty, our mouths react and our dentists can see it. With this being said, the connection between the mouth and the body is often disregarded or forgotten. While patients do not always understand it, dentists tend to concentrate on external beauty and health as opposed to internal health (and therefore beauty). It is particularly important to treat patients holistically in the current global pandemic, for them to maintain a healthy mouth and therefore a healthy body.
On the 30th of January, the World Health Organisation identified a new virus, SARS-CoV-2, to be a global emergency and urged immediate lockdown to reduce the risk of transmission of this fatal virus. The public was learning about the virus at the same rate as the scientists were discovering, and for a moment, there was a clear sense of community. The medical and research initiatives no matter how cohesive, could not fast forward what should take months or even years of research, into weeks. So many questions are left unanswered and one of the greatest enigmas, is why some people get infected and others do not. Whilst the virus has shown a certain affinity to those with diabetes, over the age of 60, high blood pressure, heart disease, obesity and/ or heart disease, this does not explain the other 52% of seemingly healthy individuals who become infected with COVID-19 and develop complications. The complications commonly associated are acute respiratory distress syndrome, pneumonia, sepsis, septic shock and blood clots. Interestingly, patients are more likely to die from these post-viral complications highlighted, as opposed to solely from the virus.
This is not the first time that a viral infection has caused complications that eventually result in death. It was the case for the influenza pandemic in 1918, where the main cause of death was not from the virus itself, but instead from bacterial superinfections. The same goes for HIV, a virus where one of the primary causes of death is bacterial pneumonia. Despite the proven importance of superinfections in the severity of viral diseases, they are often understudied during respiratory infection outbreaks such as this one, as the diagnosis of a superinfection is complex and time consuming. It is suggested therefore, that the role of bacterial superinfections be investigated further during this pandemic. Studies have shown that 80% of patients in intensive care with COVID-19 had an exceptionally high bacterial load and required antibiotics. Furthermore, in Italy, 84% of patients admitted into ICU for COVID-19 required antibiotics, supporting the idea that bacteria plays a huge role in the development and severity of COVID-19 infections.
Why Oral bacteria?
Now that we have established that bacteria could play a huge role in exacerbating a COVID-19 infection, we have to think about what is the source of this bacteria. Is this bacteria already in the body before a patient catches COVID-19? Or does it grow during the infection unnoticed as the body focuses on fighting the virus?
There has been a lot of research and focus on the idea of the mouth being the entry point for COVID-19 and also the centre of replication and dissemination of the virus across the body. Furthermore, our mouths hold 6 billion bacteria and over 700 different bacterial species. The four main diseases associated with an increased risk of complications and death from COVID-19 are also associated with altered oral microbiomes and gum disease. The bacteria found in gum disease are implicated in inflammation of the body, pneumonia and bacteremia. Patients exhibiting severe complications from COVID-19 also often display high levels of inflammatory markers (Interleukin 2, 6 and 10), the same markers that are increased in patients suffering from gum disease. The bacteria present in the metagenome of patients severely infected with COVID-19 also included high levels of those same bacteria that are responsible for gum disease.
Oral bacteria are in an ideal location to be aspirated into the respiratory tract and help initiate or worsen conditions such as pneumonia or sepsis. Inadequate oral hygiene can therefore increase the risk of inter-bacterial exchanges between the lungs and mouth, allowing for respiratory infections and post-viral bacterial complications. A concern is that during a viral infection such as COVID-19, patients may be less likely to brush their teeth or take care of their oral health. This is exacerbated in patients suffering from severe complications who find themselves in intensive care, unable to brush their teeth themselves and intubated on a ventilator. Numerous studies have shown that improved oral care can significantly reduce the incidence of ventilator-associated pneumonia in intensive care patients as well as reducing the risk of acquiring a bacterial superinfection.
Another concern is that with this pandemic, fear has been instilled into patients who are thus scared of visiting the dental practice. It must be stressed to patients and the public that oral health is directly connected to systemic health, and a healthy mouth will help create a healthy body. Oral hygiene must be maintained if not improved during this pandemic in order to reduce bacterial load in the mouth and therefore the potential risk of bacterial superinfection. Oral care is so important, that it has even been concluded that one in ten pneumonia-related deaths in the elderly could be prevented by improving oral hygiene.
In conclusion, I want to leave you all with the responsibility to improve your oral health by visiting your dentist if you haven’t done so, and by doing what your dentist has told you at home. When we say floss twice a day, we really mean it. Many patients express concern of coming to the dental practice in fear of infection of COVID-19. Whilst like with any trip out of the house there comes a risk, visiting the dentist must be maintained and oral health must be of utmost importance. Who would have thought flossing could help save your life.