SRM Journal of Research in Dental Sciences

REVIEW ARTICLE
Year
: 2020  |  Volume : 11  |  Issue : 4  |  Page : 204--211

COVID alert in pediatric dentistry


Krittika Samaddar, Payel Agarwala, Sudipta Kar, Shabnam Zahir 
 Department of Pediatric and Preventive Dentistry, Guru Nanak Institute of Dental Sciences and Research, Kolkata, West Bengal, India

Correspondence Address:
Dr. Krittika Samaddar
C/O. Krishnendu Samaddar, Nandan Kanan, Gobardanga, Khantura, North 24 Parganas - 743 273, West Bengal
India

Abstract

The novel coronavirus disease (COVID-19) caused by SARS-CoV-2 has taken the form of a pandemic that is threatening the public health and economies across the world. Statistics from various studies initially provided relief due to the lower incidence of COVID-19 occurrence in children. However, this respite was short lived as recent studies suggest that the children tend to be mostly asymptomatic, therefore, raising the possibility of lower testing and subsequent lower detection of cases. Certain articles have even termed the children “silent killers” by accusing them of secretly transmitting the SARS-CoV-2 infection without anybody suspecting them. This particular point tends to be scary, especially for the pediatric dentists because of their proximity to children during treatment which may unknowingly place them at a greater risk of viral exposure if the concerned child is asymptomatic. This review article will try to find answers to why are children shielded from the symptoms and severity of this pandemic and will also provide the pediatric dentists with information to spot the “red flags” as soon as possible.



How to cite this article:
Samaddar K, Agarwala P, Kar S, Zahir S. COVID alert in pediatric dentistry.SRM J Res Dent Sci 2020;11:204-211


How to cite this URL:
Samaddar K, Agarwala P, Kar S, Zahir S. COVID alert in pediatric dentistry. SRM J Res Dent Sci [serial online] 2020 [cited 2022 Sep 30 ];11:204-211
Available from: https://www.srmjrds.in/text.asp?2020/11/4/204/308783


Full Text

 Introduction



The ongoing coronavirus disease (COVID-19) pandemic is a notorious menace that has smothered the normalcy of human lives and has left the world grasping for an “unmasked” tomorrow. The initial available reports provided relief; for instance, the Chinese Center for Disease Control and Prevention in a study involving 44,672 confirmed cases found 416 confirmed cases in the 0–9 years' age group (0.9%) with no fatalities and 549 cases in the 10–19 years' age group (1.2%) with one fatality (0.2%).[1] An Italian study also suggested similar results with 0.5% of confirmed cases in the 0–9 years' age group and 0.7% of confirmed cases in the 10–19 years' age group with no deaths reported.[2]

The lesser percentage of severe cases among children had been attributed to lesser exposure and immaturity of angiotensin-converting enzyme 2 (ACE2) receptors. However, preschool-aged children and infants exhibited more severe clinical manifestations.[3] However, this respite was short lived since a study conducted by the Chinese Center for Disease Control and Prevention found that the majority of the cases in children – more than 90% – were mild or asymptomatic.[4] Similar allegations were put forward by the Israel Health Ministry's report on 276 COVID-19 confirmed cases, in which 27% of the children were asymptomatic in the 0–9 years' age group, whereas 7%, 4%, and 7% were the asymptomatic infection percentages in the 20–29, 50–59, and 70–79 years' age groups, respectively.[5] Therefore, the majority of the cases may have escaped testing due to the absence of symptoms.

 First Reported Cases in Children



No children were reported positive in November and December of 2019 and in the first 2 weeks of January 2020.[6] Three case series were published involving the infected children.[7] The first included 20 children up to January 31, 2020, the second included 34 children between January 19, 2020, and February 7, 2020, and the third included 9 infants from different provinces in China.[7] The youngest case reported from China was that of a neonate born to a COVID-19-positive mother on February 2, 2020, in Wuhan. The newborn was diagnosed with SARS-CoV-2 just 30 h after birth.[8] In India, the first child case was that of a 3-year-old in Kerala.[9]

 Mechanism of Viral Infection



The ACE2 receptors form the common doorway for SARS-CoV-2 entry into the human body both in the case of an adult and a child.[10] ACE2 converts angiotensin II to its metabolite angiotensin-(1–7) (Ang-1–7). Ang-1–7 has antihypertensive and profibrotic effects; the downregulation of ACE2 protein can result in inflammation and hypoxia leading to hypertension, chronic heart failure, and lung injury.[2]

 COVID Exclusiveness in Children



The following theories explain why children are relatively shielded from this fateful pandemic.

Preexposure to other human coronaviruses

While the majority of the common colds are caused by rhinoviruses, 15% of the rest are due to human coronaviruses (HCoVs).[7] HCoVs generally cause infections between December and May in the Northern Hemisphere while between March and November in the Southern Hemisphere.[7] Preexposure to milder coronaviruses and other petty pathogens may induce antibody production in children which may be versatile enough to protect against SARS-CoV-2 as well.[11]

Trained immunity

“Trained immunity” represents the innate immunity cells' ability to act as “memory cells” after antigen exposure due to an age-dependent maturation of the immune response in response to repeated stimuli, especially relevant in older children.[2],[12] Increased activation of antigen-presenting cells on pathogenic exposure leads to nonspecific host resistance to re-infection and also provides cross-protection against other pathogens.[2],[12]

An abundance of angiotensin-converting enzyme 2 receptors

ACE2 receptor has a dual role in this pandemic. Human ACE2 is an established functional receptor of SARS-CoV-2.[10] Hence, a greater number of ACE2 receptors should equal a greater number of viral entry portals. However, ACE2 receptors exhibit certain biological functions which can justify the fact that they are falsely vilified. ACE2 limits angiotensin II triggered adverse reactions in the body by degrading it to angiotensin.[13],[14] ACE2 receptors also generate Ang-1–7 which exerts numerous salutary and counter-regulatory effects to those of angiotensin II.[13] SARS-CoV-2 mostly affects older adults with increased vulnerability in males and those with hypertension, diabetes, and history of cardiovascular disease as frequent comorbidities; interestingly, all these vulnerable conditions share a variable degree of ACE2 deficiency.[13],[15] Therefore, ACE2 deficiency can play a pivotal role in the pathogenesis of SARS-CoV-2 infection.[13]

More lymphocytes and T-cells

In healthy children, lymphocytes are present in a greater amount than healthy adults due to frequently experienced viral infections in childhood.[2] The young immune system and its efficient T-cells can do a superior job in fighting SARS-CoV-2 because of their unique effectiveness against respiratory viruses.[16],[17]

Balanced immune response

Many of the worst cases of SARS-CoV-2 in adults appeared to result from hyperactive immune responses that ended up destroying healthy cells alongside infected ones in a phenomenon which can be uncommon in children.[11] Very immature immune systems like the ones in infants because of lesser exposure to pathogens may be too delicate to fight off SARS-CoV-2.[4] However, after a few years of aging up, children's immune systems may reach a sort of balanced status, strong enough to fight against the infection without overreacting.[11]

Therefore, all these factors favor the children largely in the race against SARS-CoV-2 as compared to the adults.

 Clinical Characteristics



The median age is 6.7 years.[18] The incubation period can be longer than the normal range of 1–14 days.[19] Fever and cough were found to be the most common clinical manifestations accompanied by fatigue, myalgia, nasal congestion, runny nose, sneezing, sore throat, headache, dizziness, vomiting, and abdominal pain.[19] A few children, however, do not exhibit fever but only manifest cough or diarrhea. Some may manifest vomiting, diarrhea, and other gastrointestinal symptoms, or only shortness of breath.[20],[21] Symptoms in infants are hard to notice. Some distinct symptoms of infants such as irritability, decreased response, and poor feeding could be the sign of infection.[22],[23] For SARS-CoV-2, the medial values of the reproduction number is 1.4–5.7.[24]

Anosmia and dysgeusia

Acute-onset loss of smell or taste, particularly in the context of a patent nasal airway, can be a symptom of SARS-CoV-2 infection.[25]

Conjunctivitis

A case report described that an unnamed 65-year-old woman, Italy's first confirmed COVID-19 case, had conjunctivitis in both her eyes.[26] Ocular fluids from SARS-CoV-2-infected patients may contain infectious virus and hence may be a potential source of infection.[27]

Another case report showed that SARS-CoV-2 infection occurred to a susceptible person working in a fever clinic who wore an N95 mask covering mouth and nose without eyes protected, suggesting a transmission to eyes.[28]

Diarrhea

Diarrhea may be the first or only symptom in some infected patients due to higher ACE2 expression in the small intestine, duodenum, and colon compared to the lungs.[29]

COVID toes

Tender chilblain-like “bumps” on the tops and tips of fingers, toes, and feet were present in some infected young patients who were asymptomatic or tested negative at early stages of the disease, which may be due to the formation of minor blood clots or due to a primary inflammatory response on viral exposure.[30],[31]

Increased occurrence of such symptoms in children in recent pandemic times was reported; an alert was issued by different authorities to the concerned physicians suspecting a viral etiology.[30],[31]

Multisystem inflammatory syndrome in children

A recently reported SARS-CoV-2-associated condition in children and adolescents (similar features such as Kawasaki disease or toxic shock syndrome) characterized by a persistent fever and a variety of signs and symptoms including multiorgan involvement and elevated inflammatory markers.[32]

 Modes of Transmission



Respiratory droplets (>5–10 μm in diameter)

These droplets can transmit infection through coughs and sneezes.[33]

Airborne transmission through droplet nuclei (<5 μm)

Droplet nuclei containing microbes can remain in the air for longer periods and can be transmitted to others over a distance >1 m; airborne transmission can be possible in certain circumstances.[33],[34]

Fomite transmission

Transmission may occur through fomites in the immediate environment around the infected person; SARS-CoV-2 was found to be more stable on plastic and stainless steel (till 72 h) than on copper (till 4 h) and cardboard (till 24 h).[34]

Salivary droplets

Saliva from the infected cases contained SARS-CoV-2 RNA.[28],[35] Large droplets (diameter >60 μm) tend to quickly settle, so infection through large droplets is limited to individuals near the infection source.[28] Small droplets (diameter ≤60 μm) despite being involved in short-range transmission (<1 m) can evaporate into droplet nuclei (diameter <10 μm) in a favorable environment, thereby facilitating long-range aerosol transmission.[28]

 Other Possible Routes of Transmission



COVID-19 RNA was found in the feces of infected patients suggesting the possibility of fecal-oral transmission.[36] A COVID-19 antibody (IgM) was found in a newborn's blood sample drawn 2 h after birth. IgM antibodies usually do not appear until 3–7 days after infection, therefore, hinting at a possible placental transmission.[37],[38]

 Diagnosis



The criteria for COVID-19 diagnosis in children are formulated based on adults' diagnostic criteria, combined with the epidemiological characteristics and clinical manifestations in children.[39]

Confirmatory tests

Reverse transcriptase polymerase chain reaction (RT PCR) and genetic sequencing of the respiratory tract or blood samples.[40]Genetic sequencing of the respiratory tract or blood samples.

Rapid tests – These are based on either antigen or antibody detection; the former will detect the virus when it is actively replicating and therefore is best to identify acute or early infection while the latter depends on age, nutritional status, the severity of the disease, certain medications, and immunosuppressive conditions.[41] Antibody-based tests can give false-negative results since antibody response is developed mainly in the 2nd week after the onset of symptoms and will therefore give a positive result only in the recovery phase.[41] Antibodies targeting SARS-CoV-2 may also cross-react with other pathogens, including other HCoVs, therefore, yielding false-positive results.[41]Chest computed tomography (CT) – The sensitivity of chest CT is greater than that of RT-PCR.[42] In infected children, ground-glass opacity (GGO) of a more localized extent, lower attenuation, and less lobular involvement, mainly in the peripheral and posterior lungs that did not spare the subpleural regions, is the most frequently observed performance.[39] Diffused consolidations and GGO in both lungs, with a “white lung” appearance of the right lung, were found in severe cases.[39]

In a study done on 636 ambulatory COVID-19-positive patients, 60% showed normal chest X-ray findings, indicating that chest X-ray is inadequate for proper diagnosis.[43]

Swab specimens – Nasopharyngeal and oropharyngeal swabs for upper respiratory specimens and sputum and/or endotracheal aspirate or bronchoalveolar lavage for lower respiratory specimens are the most popular ones for SARS-CoV-2 detection.[40] However, these swabs are relatively invasive, induce coughing, and cause occasional bleeding resulting in increased risks of health-care workers' infection[28]Saliva specimen – Collection is more acceptable for patients and more secured for health-care workers due to its noninvasive and less hazardous nature and has received FDA emergency use authorization.[28],[44]

Three approaches of saliva collection have been reported – coughing out (deep throat saliva), saliva swabs (oral cavity), and directly from the salivary gland duct.[28] Saliva reached the peak of viral load during the 1st week of symptom onset and then declined; viral RNA was detected in saliva even after treatment and clinical recovery.[28]

Several studies have shown the presence of ACE2 receptors in the salivary gland, buccal and gingival tissues, epithelial cells of the tongue, oral mucosa, and epithelial cells lining the minor salivary gland ducts.[28] The spike glycoprotein of SARS-CoV-2 contains a potential cleavage site for furin proteases which are expressed in the tongue.[28],[45]

 Treatment



The World Health Organization does not recommend any specific treatment in children or adults. However, certain treatment protocols depending on the type of case [Table 1] are being utilized.[39],[40]{Table 1}

Supportive treatment (for mild-to-moderate cases) includes sufficient fluid and calorie intake and broad-spectrum antibiotics (in case of suspected bacterial superinfection).[7]

In children, the use of nebulized interferon alpha-2b and oral lopinavir/ritonavir together with corticosteroids for disease complications and intravenous immunoglobulin for severe cases is the only recommendation so far.[22]

 Vaccines



The main antigens for vaccine development against SARS-CoV-2 are the structural spike glycoprotein S or its receptor-binding domain.[7] However, the tendency of coronaviruses to rapidly mutate and recombine poses a potential problem for vaccine development.[7]

 Considerations for Pediatric Dentists



The following strict precautions have to be taken provided the asymptomatic viral prevalence in children:[46]

Every patient has to be considered as a potential asymptomatic COVID-19 carrierRecovered patients should be considered as potential virus carriers for at least 30 days after the recovery confirmationTreatment needs have to be categorizedMinimum invasive procedures have to be performed accordinglyContact and airborne precautions need to be taken alongside the proper use of personal protective equipment (PPE) as per guidelines.[47],[48]

Personal protective equipment recommendations by the Occupational Safety and Health Administration for dentistry during the COVID-19 pandemic:[49] Mandatory standard PPE (gloves, gown and eye protecting goggles or face shield), The National Institute for Occupational Safety and Health (NIOSH) certified, disposable N95 filtering facepiece respirator or better (R95, P95, or better filtering facepiece; elastomeric respirator with an appropriate cartridge; or powered air-purifying respirator for extended procedures) for aerosol-generating procedures in all patients and also for nonaerosol-generating procedures in infected or suspected patients.For performing nonaerosol generating procedures in patients, where the infection is not suspected or confirmed, work clothing, (e.g., scrubs/lab coat/ smock/ gown etc.), gloves, eye protection (e.g., goggles and face shield), face mask (e.g., surgical mask) is recommended.

Every patient has to be screened meticulously based on the following criteria:[40]

Suspected case – If the patient has: Clinical symptoms of COVID-19 infection without any other underlying etiology or symptomatic and travel history to a location with reported cases of local transmission 14 days before the onset of symptoms or symptomatic and history of coming in contact with a COVID-19-positive patient 14 days before the onset of symptomsProbable case – A suspected case whose laboratory testing result for SARS-CoV-2 is inconclusiveConfirmed case – A patient with laboratory confirmation of SARS-CoV-2 infection, irrespective of the clinical signs and symptoms.

Categorization of dental treatment needs:[46],[50]

Emergency procedures (Type a) – Includes any maxillofacial trauma or swelling or infection which compromises a patient's airway or causes trismus or extends to the eye or associated with pyrexia. Also includes uncontrolled postoperative bleedingUrgent procedures – Traumatic dental injuries resulting in a complex injury to the permanent dentition (avulsion or severe luxation causing occlusal interference or any injury leading to pulp exposure). Traumatic dental injuries to the primary dentition resulting in pulp exposure or severe luxation such that tooth mobility constitutes a potential airway risk and/or is severely interfering with occlusion/function. Severe dental pain from irreversible pulpitis which does not respond to analgesics and hampers normal physiologic functions. Priority treatment should be provided to children with underlying medical conditions that place them at enhanced risk of complications arising from any subsequent infection if the tooth remains untreated and special children in whom dental pain is having a severe impact on the child/family with evidence of self-inflicting harmful behavior. Includes the following:

1. Urgent procedures not involving aerosol production (Type b)

2. Urgent procedures involving aerosol production (Type c)Nonurgent procedures (Type d) – Adjustment or repair of removable dentures, chronic periodontal disease, asymptomatic defective fixed prosthesis, or orthodontic applianceElective procedures (Type E) – Initial oral examination, periodic oral health check-ups, esthetic dental treatment, replacement of missing tooth/teeth, extraction or restoration of asymptomatic teeth, routine dental cleaning and preventive therapies, and the orthodontic treatment procedures which do not fall under Type B and Type C.

The above categories are allocated according to patient type [Table 2].[46]{Table 2}

The following children should be prioritized for urgent treatment under general anesthesia:[50]

Traumatic injury resulting in severe pain which cannot be managed by local anesthesia or sedationAcute dental infection that is not responsive to antibioticsIntractable pain or discomfort which cannot be managed under local anesthesiaFacial swelling of oral etiology, where treatment with local anesthesia is not possibleChildren whose poor dental health is impacting on, or is highly likely to impact on, their medical health like children with diabetes, cardiac conditions, epilepsy, or inherited metabolic disorder, considering that the benefits of surgery outweigh the risks of bringing a child into a hospital during the COVID-19 pandemicSpecial children such as those with learning disabilities or autism, in whom dental pain is resulting in self-harm or other disruptive or detrimental behaviorsPatients who have a compromised swallow and are at risk of aspirating a tooth that cannot be removed under local anesthetic.

The dental office particulars are:[50],[51],[52],[53]

Visual alerts promoting SARS-CoV-2-associated awareness and etiquette should be displayed at the entrance and strategic placesPatients and the accompanying person (caregiver) are requested to wear a face cover, are discouraged from wearing a wristwatch, hand and body jewelry, carrying additional accessories, bags, etc., and are also to be screened for symptoms when entering the facilityGlass or plastic barrier at the reception desk should be installedDistant chairs, preferably a meter apart to be ensured in the waiting room, which should be made free of all fomites such as magazines, toys, television remotes, or similar articlesOverlapping appointments should be minimizedSix feet of distance between patient chairs should be ensuredOperatories should be oriented parallel to the direction of airflow if possibleHigh-volume extraoral suction and fumigation systems should be installedIndoor portable air cleaning system equipped with HEPA filter and ultraviolet light may be usedThe dental chair water lines and handpieces should be equipped with antiretraction valvesMaintenance of natural airflow with the frequent opening of windows and doors while avoiding the use of a ceiling fan during the treatment procedure should be ensuredA table fan should be placed behind the operator while letting the airflow toward the patientA strong exhaust fan should be so located to create a unidirectional flow of air away from the patientThe air condition system should be frequently servicedThe procedures and prescription should be recorded only after doffing the PPECOVID-19-positive patients should be treated at the end of the day in an isolation room with negative pressureA COVID-19 assigned team for a positive patient should be established.

Below are the basic treatment considerations:[46],[54]

Minimally invasive or atraumatic restorative techniques should be preferred.Aerosol-generating procedures need to be avoided whenever possible.Intraoral imaging should be restricted and extraoral radiographs should be utilized to reduce the excessive salivation and gag reflex associated with intraoral radiographs.0.23% povidone-iodine mouthwash for at least 15 s before the procedure can reduce the viral load in the patient's saliva.While treating avulsed teeth, a bracket and wire type splint can be utilized to minimize the need for an aerosol-generating procedure for removal. A slow handpiece for splint removal with further removal of composite following the pandemic should be preferred.Deciduous teeth with symptoms arising from pulp exposure should be extracted.Inhalational sedation should be preferred over general anesthesia.Disposable and single-use instruments and devices should be used to reduce cross-infections.A rubber dam should be used.Ibuprofen prescription should be avoided in suspected and confirmed COVID-19 cases.A systemic review, however, suggested that nonsteroidal anti-inflammatory drugs do not influence COVID-19 infection severity.[55]

 Conclusion



Children form a major fraction of unrepresented cases in the epidemiological statistics due to the majority of them being asymptomatic. In India, more than 80% of transmission is through asymptomatic carriers.[56] This is alarming for the pediatric dentists; therefore, a thorough knowledge of the COVID characteristics in children is essential for not only physicians or pediatricians but also to the pediatric dentists as well.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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