Corona Virus - A History And How It Impacts On Dental Care

With the UK currently in shut down due to the Coronavirus, I thought it would be useful to post some information on the background of the virus and how it affects us as a dental practice at Progressive Dentistry. We are currently open for emergency treatments only and those at low risk of transmission. Please feel free to contact me: e nissit@progressivedentistry.co.uk WhatsApp +44 7508 663942 Dr Nissit Patel

Background

In late December of 2019 in Wuhan, the capital city of the Chinese province Hubei, a cluster of pneumonia cases of unknown origin was reported. These are now thought to be the first cases of infection with the virus that is now commonly known as Coronavirus. Most of the initial cases were linked to a wholesale seafood market, which also sold live animals and therefore it is believed that the disease originated by zoonosis, where an infection is transmitted to humans from animals (bats or possibly pangolins in this case).

As we now know, despite the launching of what has been described as the largest quarantine in human history , the viral infection spread across most of the other Chinese provinces and to date to another 170 countries by human to human transmission.

On the 11^th March 2020 the World Health Organization (WHO) classified the disease as a global pandemic of which Europe is currently the new epicentre, with Iran and South Korea also being badly affected.

Some commentators have described the pandemic as the biggest global event since the second World War .

What is a Coronovirus?

Coronaviruses are a large family of common viruses that cause illnesses ranging from the common cold to more severe diseases e.g. Severe Acute Respiratory Syndrome (SARS).

The current international pandemic of respiratory infections is caused by a new strain of Coronavirus that has not been previously identified in humans. It has been given the official name COVID-2019 (shortened to COVID-19). While scientific studies are ongoing it is generally agreed that:

• The virus primarily spreads between people in a manner similar to influenza
• Spread is via respiratory droplets that people exhale e.g. when coughing and sneezing
• It is considered most contagious when people are symptomatic
• The time between exposure and symptom onset is typically five days but may range from two to fourteen days
• Patients may be infectious before onset and then for seven days after symptoms appear.

An excellent update on the microbiology of Coronavirus can be found by following this link to a youtube video recorded by Professor Alan McNally Director of microbiology and infection at the University of Birmingham. https://www.youtube.com/watch?v=TB_2pObdmz8

Symptoms

If infected with Coronavirus, symptoms vary from person to person. Fortunately, in the vast majority of cases symptoms are mild and may mimic the common cold or influenza. Classic symptoms include fever, persistent cough, and shortness of breath.

As we know Coronavirus infection can occasionally cause more severe symptoms. This is more likely in people with weakened immune systems, elderly people, and those with chronic conditions such as diabetes, chronic lung disease, cardiovascular disease and cancer. Complications may include acute respiratory distress syndrome, pneumonia and even death.

Treatment

As there is currently no specific vaccine or antiviral medication for coronavirus, treatment aims to relieve patient s symptoms while their bodies fight the illness. Antibiotics do not help, as they do not work against viruses, although they may be prescribed if a diagnosis of secondary bacterial infection is made.

Infected people need to stay in isolation, away from other people, until they have recovered. This forms the basis of the internationally recognised protocols designed to limit further spread of the disease. The widely publicised rules that follow apply to people of all ages, and of course include all members of our dental teams.

Department of health guidelines

COVID-19 is a new illness that can affect your lungs and airways. It is caused by a virus called coronavirus.

• Stay at home if you have coronavirus symptoms
• Stay at home if you have either:
• a high temperature this means you feel hot to touch on your chest or back (you do not need to measure your temperature)
• a new, continuous cough this means coughing a lot for more than an hour, or 3 or more coughing episodes in 24 hours (if you usually have a cough, it may be worse than usual)
• Do not go to a GP surgery, pharmacy or hospital
• Use the 111 online coronavirus service to find out what to do
• Only call 111 if you cannot get help online and symptoms are worsening/persisting

How long to stay at home?

• If you have symptoms of coronavirus, you'll need to stay at home for 7 days
• If you live with someone who has symptoms, you'll need to stay at home for 14 days from the day the first person in the home started having symptoms
• If you live with someone who is 70 or over, has a long-term condition, is pregnant or has a weakened immune system, try to find somewhere else for them to stay for 14 days.
• If you have to stay at home together, try to keep away from each other as much as possible.

How to avoid catching and spreading coronavirus (social distancing)

Everyone should do what they can to stop coronavirus spreading, by limiting social contact and keeping 2 metres/6 feet apart from others.* It is particularly important for people who:

• Are 70 or over
• Have a long-term condition
• Are pregnant
• Have a weakened immune system

*Clearly this is impossible in dental surgeries, but we will entact this as best as possible by limiting patient numbers within the practice and allowing plenty of time between emergency patients.

How coronavirus is spread?

• Because it's a new illness, we do not know exactly how coronavirus spreads from person to person.
• Similar viruses are spread in cough droplets.
• It's very unlikely it can be spread through things like packages or food.
• Washing hands regularly for 20 seconds or more remains the single most important thing each of us can do, but we now also need to ask everyone in a household to stay at home if anyone in their home shows symptoms.

Coronavirus guidelines from the Faculty of General Dental Practitioners

The recently published guidelines have been updated in accordance with the 'delay' phase of the coronavirus pandemic. They have an unprecedented impact on the routine practice of dentistry in the UK. The Faculty of General Dental Practice (FGDP) have summarised the recently published national guidelines and provided definitions as follows: The key new points, effective immediately, are:

• Cease all (dental) care of anyone who should be self-isolating (whether or not they are symptomatic)
• Cease non-urgent care for patients who are 70 or older, pregnant or have a serious underlying health condition
• Cease all aerosol generating procedures for all patients receiving non-urgent care
• Where aerosol generating procedures are necessary, the dental team should all wear a full-face shield or goggles/visor in addition to a surgical face mask

Practices are also advised:

• To establish which patients are or should be self-isolating prior to appointments (travel history is now irrelevant)
• Anyone who has a new and continuous cough, or a temperature of at least 37.8 degrees, should stay at home for 7 days
• Anyone sharing a household with someone with one of those symptoms should stay at home for 14 days, and if they become symptomatic themselves, 7 days from that point in time
• To postpone routine care for patients who are or should be self-isolating
• Not to provide urgent or emergency care for patients who are or should be self-isolating; they should be seen in dedicated centres which are being established*, and not in general practice (*see national guideline documents for locations of these centres)
• To identify patients in high risk groups ( social distancers ) and postpone their routine appointments
• To offer cancellation to anyone who wishes to avoid travel
• To review all open courses of treatment for all patients, and identify those requiring care that cannot be postponed
• To ask patients to travel unaccompanied where appropriate
• To wipe down door handles and other surfaces between patients with extra vigilance
• To remove all unnecessary items from waiting rooms and work surfaces
• To provide handwashing facilities for patients and carers
• To cancel domiciliary visits for routine care
• To establish business continuity plans
• To ensure practices are registered to receive email updates from the NHS

Definitions of routine, urgent and emergency care are provided in the NHS England commissioning standard for urgent dental care.

Routine care includes treatment for:

• Mild or moderate pain: that is, pain not associated with an urgent care condition and that responds to pain-relief measures
• Minor dental trauma
• Post-extraction bleeding that the patient is able to control using self-help measures
• Loose or displaced crowns, bridges or veneers
• Fractured or loose-fitting dentures and other appliances
• Fractured posts
• Fractured, loose or displaced fillings
• Treatments normally associated with routine dental care
• Bleeding gums

Urgent care includes treatment for:

• Dental and soft-tissue infections without a systemic effect
• Severe dental and facial pain: that is, pain that cannot be controlled by the patient following self-help advice
• Fractured teeth or tooth with pulpal exposure

Dental emergencies include:

• Trauma including facial/oral laceration and/or dentoalveolar injuries, for example avulsion of a permanent tooth
• Oro-facial swelling that is significant and worsening
• Post-extraction bleeding that the patient is not able to control with local measures
• Dental conditions that have resulted in acute systemic illness or raised temperature as a result of dental infection
• Severe trismus
• Oro-dental conditions that are likely to exacerbate systemic medical conditions such as diabetes (that is lead to acute decompensation of medical conditions such as diabetes)

Aerosol Generating Procedures

• Recent COVID-19 guidance for infection prevention and control in healthcare settings states that human coronaviruses can survive on inanimate objects and can remain viable for up to 5 days at temperatures of 22-25 °C and relative humidity of 40-50% (which is typical of air-conditioned indoor environments)
• Recent guidance highlights the risk of extensive environmental contamination from the use of potentially infectious Aerosol Generating Procedures including some dental procedures .
• The CDOs have decided on a precautionary basis to advise dentists to cease all aerosol generating procedures for all patients except where it is required for urgent care.

To help clarify this new advice, the CDO for Scotland has provided the following non-exhaustive list of Aerosol Generating Procedures (AGPs):

• Use of high-speed handpieces for routine restorative procedures
• Use of Cavitron, Piezosonic or other mechanised scalers
• Polishing teeth
• High pressure 3:1 air syringe ( NB Risk of aerosols could be reduced when using a 3:1 if only the irrigation function is used, followed by low pressure air flow from the 3:1 and all performed with directed high volume suction. Dry guards, cotton wool or gauze can also help with drying and moisture control )

The same letter also provides a non-exhaustive list of non-AGPs, which may continue for appropriate patients:

• Examinations
• Hand scaling with suction
• Non-surgical extractions ( NB If this became a surgical extraction, a slow speed reducing handpiece could be used for bone removal, with cooling provided using saline dispensed via a syringe along with high speed suction. If this is not a suitable option, temporisation or referral would need to be considered )
• Removable denture stages
• Removal of caries using hand excavation or slow speed handpiece if necessary

An exception is made for opening teeth for drainage, where a high-speed handpiece would be required. The advice would be to use rubber dam, which considerably reduces aerosol production, along with high volume suction. The operators should wear a full-face visor and fluid-resistant mask

Addendum: In the recently published guidelines, it is interesting to note that the use of rubber dam isolation is only mentioned with regard to emergency endodontic procedures. The reported benefits of employing rubber dam to signiï¬cantly minimize the production of saliva- and blood-contaminated aerosol or spatter for other urgent treatments may be included in future guidelines.

Infection Control

Effective infection control strategies are essential to prevent the spread of Coronavirus. Effective handwashing has been identified as the most important personal measure that the general public (and dental teams) can employ to protect against infection with and/or spread of coronavirus. The internationally recognised campaign to optimise regular handwashing consists of the following protocols:

• Avoid touching the eyes, nose, or mouth with unwashed hands
• Wash hands often with soap and water for at least 20 seconds, especially after going to the toilet or when hands are visibly dirty; before eating; and after blowing one's nose, coughing, or sneezing
• Use an alcohol-based hand sanitizer with at least 60% alcohol by volume when soap and water are not readily available
  

Respiratory Hygiene

Health organizations also recommended that people cover their mouth and nose with a bent elbow or a tissue when coughing or sneezing (the tissue should then be disposed of immediately). (Catch it, Kill it, Bin it) The use of surgical masks by the general public is the subject of controversy. While they are a low grade of protection, and are completely permeable to viruses, masks may limit the volume and distance travelled of droplets dispersed during talking, sneezing and coughing and are designed mainly to protect others from the wearer. (Masks designed to protect the wearer are technically "respirators", though calling them "masks" is common). While masks may reduce the risk of involuntary face touching, poorly applied masks may actually increase this risk. The world health organisation (WHO) has recommended the wearing of masks by healthy people only if they are at high risk, such as those who are caring for a person with Coronavirus infection.

Infection Control In Dental Practice

Dental care settings invariably carry the risk of infection as they involve:

• Face-to-face communication with patients (Direct contact of conjunctival, nasal, or oral mucosa with droplets containing microorganisms generated from an infected individual and propelled a short distance by coughing and talking without a masks)
• Frequent exposure to saliva and blood
• The handling of sharp instruments
• Inhalation of airborne microorganisms that can remain suspended in the air for long periods
• Indirect contact with contaminated instruments and/or environmental surfaces
• Human coronaviruses can persist on surfaces like metal, glass, or plastic for up to five days
• Aerosols (see above)

Even with the recently introduced limitations on the scope of dental practice, the infection control, disinfection and decontamination procedures that are a routine part of everyday clinical practice, take on even greater significance in supporting the national effort to slow the spread of Coronavirus and reduce the burden on secondary care.

Personal protective equipment (PPE)

Potential PPE shortages were recently highlighted by the British Dental Association (BDA). The response to BDA members concerns regarding the limited availability of face masks is as follows:³

• The global mask shortage has been caused because most of the world's hygienic masks are manufactured in China, now in the grip of the Coronavirus (COVID-19) outbreak.
• Under the current guidance all dentists should wear Personal Protective Equipment (PPE) including disposable face masks, clinical gloves, and eye protection (where appropriate).
• NICE Guidelines state "face masks and eye protection must be worn where there is a risk of blood, body fluids, secretions or excretions splashing into the face and eyes."
• Only Scotland permits visors and disposable masks to be used interchangeably.
• The Department of Health and Social Care indicated significant central stockpiles exist, including reserves built up for the UK's departure from the European Union.
• Supplies from these stockpiles have been released to ease immediate pressures. At present these stocks are only being offered to suppliers serving practices in England.
• Check mask stock and status of orders with your regular suppliers.
• Practices should maintain clarity on their daily consumption of masks, for both treatment and decontamination, and wherever possible minimize waste
• Daily ordering limits in place with some wholesalers mean some larger practices faced being unable to operate at normal levels.

In further response to concerns over maintaining stocks of appropriate personal protective equipment, NHS England/NHS improvement have published detailed updates on the supply of PPE and guidance on optimising its usage. These updates may be found by following this link: https://www.england.nhs.uk/coronavirus/publication/guidance-supply-use-of-ppe/ None of us has ever experienced the current level of uncertainty resulting from a combination of: health fears for our families, friends and patients, new travel restrictions, quarantines, curfews, event postponements and cancellations, border closures; all compounded by widespread fears of supply shortages across various sectors. The extraordinary economic impact of these new clinical guidelines on dental businesses, coupled with the wider socioeconomic disruption is unparalleled. As with all businesses at this time we are facing unprecedented challenges. Please rest assured however that we are working as best we can to support you through every stage of this unprecedented, and hopefully short, period of our professional lives.

Resources and references

• NHS Coronavirus standard operating procedures
• BDA Coronavirus live updates
  
• FGDP Coronavirus guidelines summary
• Department of health and social care. COVID-19 Guidance for infection prevention and control in healthcare settings
  

References

• Meng L. et al. Coronavirus Disease 2019 (COVID-19): Emerging and Future Challenges for Dental and Oral Medicine. Journal of dental research. March 2020