Coronavirus. COVID-19. SARS-CoV-2. The virus. Whichever name you know it by, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has likely had a huge affect on nearly every aspect of your life over the past months. Most people in the world have been touched in some way, whether through changes in work, school, or family life, health concerns, or economic challenges, by this novel disease that has become a worldwide pandemic. Although much remains unknown about this virus and its management, there are some preliminary conclusions we can make that will be helpful as we continue to monitor and manage the pandemic while we balance daily life and learn to live in the world of coronavirus disease 2019 (COVID-19).
What Is This New Virus?
Coronaviruses are enveloped, single-stranded RNA viruses that belong to the order Nidovirales family Coronaviridae.1–4 They are further classified into genus Alphacoronavirus or Betacoronavirus.1 They are zoonotic viruses, meaning they live in animals and they mutate rapidly forming new viruses that can be transmitted from animals to humans.2,3 Coronaviruses are primarily found in bats, rodents, civets, and humans.2 SARS-CoV-2 is a Betacoronavirus.1
Coronaviruses are common in humans and can be isolated from 4% to 6% of children who are hospitalized for an acute respiratory infection and from 8% of children in the ambulatory setting.2 About 15% to 30% of common colds are caused by coronaviruses, and symptoms are generally mild.4,5 They can, however, lead to more significant illness such as bronchiolitis, pneumonia, severe acute respiratory distress syndrome, coagulopathy, multi-organ failure, and even death.2 Anywhere from 11% to 46% of the time when coronavirus is detected, it is present as a coinfection with other respiratory viruses such as respiratory syncytial virus (RSV), influenza, parainfluenza, adenovirus, bocavirus, and rhinovirus.2
Where Did SARS-CoV-2 Come From?
In December 2019, in Wuhan, Hubei province, China, a new respiratory illness was spreading.5–7 It was identified as a coronavirus and by January 2020, genome sequencing determined that it was a novel virus.6 The National Health Commission of the People's Republic of China termed this new clinical illness COVID-19 and named the virus SARS-CoV-2. By March 2020, the World Health Organization had declared that the virus had reached pandemic levels.2,6,7 It is not certain how the virus transferred from animals to humans, although it has been postulated that it came from bats, snakes, or pangolins (an animal similar to a scaly anteater).4,6,8
This is not the first pandemic we have experienced involving a coronavirus. In 2002, severe acute respiratory syndrome coronavirus (SARS-CoV) emerged from Guangdong province in southern China.2 It is believed to have originated in bats or civet cats.2,4 Similar to what we are seeing now with SARS-CoV-2, SARS-CoV caused severe lower respiratory tract infections.2 This coronavirus had a fatality rate nearing 50% in people older than age 60 years, with an overall rate of 10%.2 An estimated 8,000 people were infected, and 774 deaths were attributed to SARS-CoV.2 The SARS-CoV-2 virus seems to be much more contagious than SARS-CoV but less deadly, with a worldwide fatality rate of about 3%.9 In 2012, Middle East respiratory syndrome coronavirus (MERS-CoV) emerged in the Middle East, likely transmitted from the dromedary camel.2,4 It also caused severe lower respiratory tract infections with a fatality rate of between 20% and 40%.2 There were 2,494 documented infections and 858 deaths from this outbreak.2 Both SARS-CoV and MERS-CoV had low potential for long-term sustained community transmission, so they were more easily controlled before they reached the high numbers we are seeing now with SARS-CoV-2.2
How Is SARS-CoV-2 Different From Other Respiratory Viruses?
Unlike most other respiratory viruses that we encounter, COVID-19 does not seem to affect children as much as adults.7,10–12 Several studies from China have shown that children younger than age 19 years account for only about 1% to 2% of all COVID-19 patients, with children younger than age 10 years in the lowest category.5–7 Italian data show a similar rate, with only 1.2% of cases occurring in the pediatric population.7 Compared to the adult population, there are far fewer pediatric patients, and for those who do get the virus, the disease tends to be milder with a better prognosis.13 This is consistent with the SARS-CoV outbreak in 2002 (<0.02% were pediatric cases) and the MERS outbreak in 2012 (2.2% were pediatric cases), where children fared better than adults.7 There are several theories about why children are less affected, including children having a more active innate immune response, healthier respiratory tracts from less exposure to smoke and pollution, and fewer underlying disorders.3,7,10 Children are also exposed to many viral infections in early childhood, and it is possible that this repeat exposure primes the immune system to respond to the SARS-CoV-2 virus more robustly than adults.7 Finally, the virus enters cells by binding to the angiotensin-converting enzyme 2 cell receptor, but this enzyme is less mature at a younger age, potentially providing some protection for children.6,7
How Is SARS-CoV-2 Transmitted?
SARS-CoV-2 is transmitted by direct inhalation of infected droplets, direct contact with surfaces and fomites contaminated with active viral particles, as well as via aerosolized viral particles (during cardiopulmonary resuscitation, intubation, bronchoscopy, nebulizer treatments).1,3,8,13 The virus can also be transmitted via the conjunctivae.6 The duration of viral viability on surfaces and fomites is unknown at this time, although surface spread seems to be a secondary mode of transmission to person-to-person contact.2,8 There appears to be little or no vertical transmission of the virus from mother to fetus.2,6,7 Breast milk can confer antibodies and should be encouraged if the mother's health permits, although a mother with COVID-19 should wear a mask at all times when handling her newborn.8,14
Many simple steps can be taken to decrease the rate of transmission and mitigate risk of contracting COVID-19. First, maintaining a social distance of 6 feet between yourself and others decreases the chance of spread.8 When in public and unable to socially distance and anytime you are inside a public place, a mask should be worn at all times.8 Good hand washing is essential.8 One family member should be assigned to interact and help those who have the illness or who are at high risk of morbidity and mortality should they catch it so as to limit contact and spread.8 Recommended quarantines should be followed with all illness to stop potential spread.
What Role Do Children Play In Transmission of SARS-CoV-2?
One of the biggest and most important questions we are addressing right now is how to contain this virus as the pandemic sweeps across the world. Communities and entire countries are grappling with how to balance the health of their citizens with the burden on the health systems, as well as the economy, education, and many other factors affected by COVID-19. One important piece of this puzzle is the role that children play in the transmission of SARS-CoV-2. We know that they do not seem to be as symptomatic as adults, but also knowing how much they spread the disease is vital for making decisions about reopening schools and daycares, assessing risk of exposed parents and at-risk family members, and the downstream impact this has on the health care system and economy as a whole.7
We know that children are susceptible to infection with SARS-CoV-2 but often do not have significant symptoms.5,12 It has also been found that viral load is similar in both asymptomatic and symptomatic patients.6 This raises the question of asymptomatic transmission and whether children act as vectors for spread of the virus.2,5 Although information is somewhat limited as the disease is still in flux around the world, there are some data to suggest that children are not major contributors to the spread of SARS-CoV-2. In many studies, the majority of children infected by this new virus have a documented household adult contact who was symptomatic first, suggesting that the adult was the index case and passed it to the child.2,3,14 A Swiss study of 39 affected households showed only three had a child as the suspected index case.11 In another study, 56% of children who tested positive were able to trace their infection to a family gathering.6 Other studies have shown similar results, indicating that children most frequently acquire COVID-19 from adults rather than transmitting it to them.3,11 Elementary school-aged children (age 10 years and younger) appear to be at the lowest risk for spreading the virus.11,12
What Does COVID-19 Look Like in Children?
As mentioned previously, children tend to be less affected when they do become infected with SARS-CoV-2.1,2,15 Other respiratory infections, such as RSV and influenza, often cause much more significant disease in the pediatric population.8 Most children with SARS-CoV-2 are asymptomatic or have mild symptoms, and fatality has been rare.3,15,16 Children also tend to recover faster and clear the virus from their system more efficiently than adults.2,6 Most children have complete recovery within 1 to 2 weeks of the onset of illness.1,2,7,13
For those children who do experience symptomatic COVID-19, their disease is clinically similar to other acute respiratory viral infections, although SARS-CoV-2 tends to produce less nasal symptoms.1,8 Children commonly report cough, sore throat, fever, and fatigue, and less frequently congestion, sneezing, and rhinorrhea.1,3,5,7,8,13,14,17 Some children also present with abdominal pain, nausea, vomiting, and diarrhea.1,3,16 Unlike adults, who frequently report loss of taste or smell, this is less common in children.16
More than 90% of children fall into the asymptomatic, mild, or moderate disease categories, which can be managed at home.3,7 About 5% develop severe disease, defined by dyspnea, central cyanosis, or an oxygen saturation <90%.7 These children require hospitalization for supportive care and monitoring. Only 0.6% of cases were considered critical, defined as respiratory or other organ failure, and these children require more interventions.3,7 In contrast, about 18.5% of adults progress to severe or critical disease.3
Children with congenital heart and lung disease, chronic heart or kidney disease, or long-term immunosuppressant use are at higher risk of complications from COVID-19.13 Interestingly, one study found that children with suspected but unconfirmed COVID-19 had more severe disease than those with laboratory confirmation, suggesting that other etiologies may have been responsible in those with unconfirmed disease.7 The differential for these patients (and all children presenting with complications) should include influenza, parainfluenza, adenovirus, RSV, rhinovirus, human metapneumovirus, mycoplasma pneumonia, chlamydia pneumonia, and bacterial pneumonia.7,13
Laboratory evaluation in children often shows normal blood counts but occasional leukocytopenia or neutropenia may be found.7,13 Only rarely are C-reactive protein and procalcitonin levels found to be elevated.3,7 Reverse-transcription polymerase chain reaction (PCR), real-time PCR, and reverse transcription loop-mediated isothermal amplification are the most common methods of testing for SARS-CoV-2.2,17 There are also antigen or serologic antibody tests available.4 Chest radiographs are generally nonspecific, whereas computed tomography imaging in pediatric patients is similar to adults with ground-glass opacities, patchy shadowing, and halo signs.2,3,6–8,13,17 Lung abnormalities are most severe about 10 days after the initial onset of symptoms.17
What Is Unique to Children with SARS-CoV-2?
There are some of manifestations of SARS-CoV-2 that seem to be specific to children. One of these phenomena has been termed “COVID” toes. Early on in the pandemic, there were several reports of skin lesions on the toes, feet, fingers, and hands that were identical to chilblains.18 Chilblains are typically uncommon in children, especially in warmer weather.18 Once the first report of “COVID” toes was published, it was discovered that this was not an isolated cluster, but in fact hundreds of young people were presenting with similar symptoms.18 One study of 22 cases showed that all patients had involvement of the feet and three cases also had involvement of their fingers.18 They tended to have acrally located, erythemato-violaceous, or purpuric macules on the toes and lateral aspects of the feet and heels along with the tips of the toes.18 There was often swelling noted, and some patients reported pruritis and mild pain.18 Many patients had no other symptoms than their “COVID” toes, about one-half reported some mild respiratory symptoms, and 40% had gastrointestinal symptoms.18 No one reported a fever.18 The lesions resolved without intervention in about 3 to 5 weeks, and all patients had excellent outcomes without any reports of complications.18
On the other end of the spectrum, there is a subset of children who become seriously ill from SARS-CoV-2. These children develop something called multi-inflammatory syndrome in children (MIS-C). This confluence of symptoms was first identified in April 2020 in the United Kingdom when a cluster of eight children were noted to have hyperinflammation and cardiovascular shock.19 Subsequently, other clusters of this illness were identified, primarily in adolescents and children older than age 5 years.19 MIS-C is characterized by fever for at least 24 hours, illness requiring hospitalization, laboratory evidence of inflammation, multisystem organ involvement, and infection with SARS-CoV-2.19 It presents similarly to another childhood illness, Kawasaki disease, which also has high fever, mucocutaneous involvement, and inflammation.19
Children with MIS-C often have involvement of the gastrointestinal system (92%) and the cardiovascular system (80%), hematologic abnormalities (76%), mucocutaneous involvement (74%), and respiratory insufficiency or failure (70%).19 In a study of 186 patients, 71% had involvement of at least four organ systems.19 Intensive care was required for 80% of patients, 20% received mechanical ventilation, and 4% required extracorporeal membrane oxygenation.19 Vasoactive support was needed for 48% of patients, and 8% developed coronary aneurysms.19 Treatment is largely supportive but intravenous immunoglobulin was given in 77% of children and almost one-half received glucocorticoids.19
Interestingly, MIS-C develops further into the course of illness, with children meeting the diagnostic criteria on average 25 days into their illness.19 This is similar to adults who tend to develop more severe symptoms as their viral load decreases, suggesting an immune-mediated process.19 Until we know more about the effects of MIS-C, and due to its similarities to Kawasaki disease, it is important to closely observe these patients and perform repeat echocardiography to monitor for aneurysm.19
How Do We Manage SARS-CoV-2 INFECTION?
The best way to manage SARS-CoV-2 is to prevent infection from occurring. Public health measures and community cooperation are essential in slowing the spread of this disease. These important measures include social distancing, quarantine, travel restrictions, mask use, handwashing, and surface disinfection.19 If we can contain SARS-CoV-2 through a public health approach, it will allow time for the development and testing of vaccines, which is the most effective strategy for preventing the spread of infectious disease.4 Not only are vaccines effective at reducing morbidity and mortality, but they are also cost-effective, as the management of the illness is often expensive in comparison to the cost to prevent it.4 There are many vaccines in development now, but none ready yet for distribution. It is unknown how long the protection from a vaccine will last as coronaviruses have a propensity to mutate rapidly, which can decrease or even eliminate the protection from antibodies formed from the vaccine.2
Treatment for someone who has been infected with SARS-CoV-2 is largely supportive. Most people (especially children) can be managed at home, but strict isolation is encouraged while doing so.3,8 In more severe cases, oxygen supplementation, fluid management, and nutrition are the mainstay of treatment.2,3,7,8 Should a higher level of support be needed, early intubation and ventilation is recommended along with prone positioning.3,8
In some cases, medication is needed to manage the symptoms of the disease. Corticosteroids should be avoided unless their use is indicated for another reason.17 Early reports suggested that hydroxychloroquine might be helpful in the management of SARS-CoV-2, but subsequent research showed that it may actually cause harm and its use is not recommended.17 There are no antivirals that are recommended for pediatric patients, although some have been tried in adults.13 There are other methods of treatment being studied, such as using convalescent plasma collected from infected donors in order to confer antibodies.17 Antibiotics may be needed in cases of bacterial superinfection.3 Finally, a big driver of severe disease is the cytokine storm produced by the infection, so plasma exchange or immunomodulators may help reduce the cytokine load and thus reduce inflammatory damage to the lungs and other systems.3,13
What About School?
One of the biggest decisions for parents in this unprecedented time is whether or not to send children back to school and how safe it is for students and their teachers. It is important to weigh the risks of school attendance with the benefits that come along with being in this important social and educational environment. For many children, school is the only space where they are safe, get a good meal, have access to social services, and so much more. For many families, keeping children at home during the school day is not a viable option. It is essential that we do our best to keep teachers, staff, and children safe, while also tending to the mental, physical, and social health of our own children.
Several studies have been done looking at this issue, and the general consensus is that younger children are less of an infection and transmission risk, but adolescents seem to spread the disease at similar rates as adults. A study by the department of health in Sweden looked at the differences between Finland, which closed schools due to the pandemic, and Sweden, which closed only secondary schools (age 16 years and older) and colleges while primary schools and daycares remained open.15 There was no difference in the overall incidence of confirmed SARS-CoV-2 cases in the group aged 1 to 19 years between the two models.15 There was also no difference between the periods of time in Finland when schools were open versus closed, supporting the idea that school closure does not greatly affect the spread of COVID-19.15 Separate studies of viral transmission in Finland also showed that children do not seem to be contributing much to the spread of COVID-19.15 During the 2-week reopening period for schools in Finland, there were 23 exposures in 21 schools. During those 2 weeks and the following 2 weeks (the quarantine period for those exposed), there were zero secondary cases from those exposures.15 A study from Sweden also compared risk for different professions and found that teachers and daycare providers showed no increased risk compared with the general population.15
A French study by Fontanet et al.16 also supports the finding that young children do not play a major role in the transmission of SARS-CoV-2. In this study, prior to school closure, there were three exposures at three different schools that resulted in zero secondary cases.16 It seems that although children carry viral loads similar to or even higher than adults, they do not seem to spread the virus nearly as much.16 Interestingly, a similar study of the high school in the same town produced significantly different results, with 38% of students, 43% of teaching staff, and 59% of nonteaching staff testing positive for antibodies to SARS-CoV-2, indicating a much higher level of spread.16
Based on the information available at this time, the American Academy of Pediatrics (AAP) has developed guidelines for returning to school, dependent upon the local transmission rates and ability to provide a certain level of protective measures.12 They strongly advocate that all plans should have the central goal of providing in-person instruction with children physically present at school.12 These plans should be adaptable to changing conditions in the community with regard to SARS-CoV-2 and also provide options to those who are high-risk or have family members who are high-risk.12 Many considerations are necessary to ensure a safe environment to which the teachers and students can return.12 Some of these measures include wearing masks (for both adults and children), physical distancing of at least 3 feet whenever possible, staggered drop-off and pick-up times, limiting the number of people in the building, and providing education and opportunity for frequent handwashing and hygiene measures.12 Other measures may include keeping students in cohorts, having teachers move from room to room instead of students, eliminating locker use, using outdoor spaces, lunch in the classrooms, and physical barriers and visual guides in the hallways to promote distancing.12 Children receiving special education or those with an individualized education plan may require a more personal plan that takes into account their particular developmental needs.12 The AAP also emphasizes the importance of having ample availability for viral testing as well as a clear plan for infection control should a student or teacher become symptomatic.12 It is also essential to address the mental health needs of the students and teachers as they navigate this unprecedented situation and completely new approach to education.12 Due to the lost time from spring distance learning as well as the fluctuations in education models that are likely to occur throughout this school year, it is important to set realistic expectations for teachers and students.12 For example, curriculum should not be “fast tracked” to catch up for previous lost instructional time, consideration should be taken to the fact that transitioning between education models can be a difficult adjustment, and allowances may need to be made in certain situations.12 It is also important to continue to provide enrichment opportunities outside of the core curriculum such as art, music, media, and physical education.12
No matter your age, race, occupation, or location, we have all been affected by SARS-CoV-2 in some way. The medical profession has had a steep learning curve not only for managing the frontlines of a pandemic but also in the rapid implementation of telehealth. The education system had to emergently rethink how we teach and alter curriculum in a matter of weeks. Now, we as a nation are preparing for a school year unlike any other we have experienced. The general workforce learned what must be done in person and what can be managed remotely. As a society, we were reminded just how intertwined we all are, not only emotionally and socially, but physically as well. We learned alternate ways to say hello and express love. We found ways to remain safe but still connect through streaming apps and socially distant gatherings. Perhaps most inspiring is the way children have used their empathy and creativity to spread joy and maintain friendships during this difficult time.
While we are slowly building our knowledge of SARS-CoV-2, and particularly how it affects children, there is still much that is unknown. We make decisions based on the best information possible but only time, data collection, and some trial and error will lead us to more answers and better management of COVID-19 in the future. If we can unite as a community and use what we learn to work toward halting the spread of the virus, we will be able to weather this storm and be better prepared to face similar situations in the future.
- Hong H, Wang Y, Chung HT, Chen CJ. Clinical characteristics of novel coronavirus disease 2019 (COVID-19) in newborns, infants and children. Pediatr Neonatol. 2020;61(2):131–132. doi:10.1016/j.pedneo.2020.03.001 [CrossRef] PMID:32199864
- Zimmermann P, Curtis N. Coronavirus infections in children including COVID-19: an overview of the epidemiology, clinical features, diagnosis, treatment and prevention options in children. Pediatr Infect Dis J. 2020;39(5):355–368. doi:10.1097/INF.0000000000002660 [CrossRef] PMID:32310621
- Balasubramanian S, Rao NM, Goenka A, Roderick M, Ramanan AV. Coronavirus disease 2019 (COVID-19) in children - what we know so far and what we do not. Indian Pediatr. 2020;57(5):435–442. doi:10.1007/s13312-020-1819-5 [CrossRef] PMID:32273490
- Ahn DG, Shin HJ, Kim MH, et al. Current status of epidemiology, diagnosis, therapeutics, and vaccines for novel coronavirus disease 2019 (COVID-19). J Microbiol Biotechnol. 2020;30(3):313–324. doi:10.4014/jmb.2003.03011 [CrossRef] PMID:32238757
- Kelvin AA, Halperin S. COVID-19 in children: the link in the transmission chain. Lancet Infect Dis. 2020;20(6):633–634. doi:10.1016/S1473-3099(20)30236-X [CrossRef] PMID:32220651
- She J, Liu L, Liu W. COVID-19 epidemic: disease characteristics in children. J Med Virol. 2020;92(7):747–754. doi:10.1002/jmv.25807 [CrossRef] PMID:32232980
- Ludvigsson JF. Systematic review of COVID-19 in children shows milder cases and a better prognosis than adults. Acta Paediatr. 2020;109(6):1088–1095. doi:10.1111/apa.15270 [CrossRef] PMID:32202343
- Sankar J, Dhochak N, Kabra SK, Lodha R. COVID-19 in children: clinical approach and management. Indian J Pediatr. 2020;87(6):433–442. doi:10.1007/s12098-020-03292-1 [CrossRef] PMID:32338347
- World Health Organization. WHO coronavirus disease (COVID-19) dashboard. Accessed September 25, 2020. https://covid19.who.int/
- Lee PI, Hu YL, Chen PY, Huang YC, Hsueh PR. Are children less susceptible to COVID-19?J Microbiol Immunol Infect. 2020;53(3):371–372. doi:10.1016/j.jmii.2020.02.011 [CrossRef] PMID:32147409
- Lee B, Raszka WV Jr, . COVID-19 Transmission and children: the child is not to blame. Pediatrics. 2020;146(2):e2020004879. doi:10.1542/peds.2020-004879 [CrossRef] PMID:32457212
- American Academy of Pediatrics. COVID-19 planning considerations: guidance for school re-entry. Accessed September 19, 2020. https://services.aap.org/en/pages/2019-novel-coronavirus-covid-19-infections/clinical-guidance/covid-19-planning-considerations-return-to-in-person-education-in-schools/.
- Shen K, Yang Y, Wang T, et al. China National Clinical Research Center for Respiratory DiseasesNational Center for Children's Health, Beijing ChinaGroup of Respirology, Chinese Pediatric Society, Chinese Medical AssociationChinese Medical Doctor Association Committee on Respirology PediatricsChina Medicine Education Association Committee on PediatricsChinese Research Hospital Association Committee on PediatricsChinese Non-government Medical Institutions Association Committee on PediatricsChina Association of Traditional Chinese Medicine, Committee on Children's Health and Medicine ResearchChina News of Drug Information Association, Committee on Children's Safety MedicationGlobal Pediatric Pulmonology Alliance. Diagnosis, treatment, and prevention of 2019 novel coronavirus infection in children: experts' consensus statement. World J Pediatr. 2020;16(3):223–231. doi:10.1007/s12519-020-00343-7 [CrossRef] PMID:32034659
- Morand A, Fabre A, Minodier P, et al. COVID-19 virus and children: what do we know?Arch Pediatr. 2020;27(3):117–118. doi:10.1016/j.arcped.2020.03.001 [CrossRef] PMID:32253003
- Public Health Agency of Sweden. Nohynek H, Helve O. COVID-19 in schoolchildren: a comparison between Finland and Sweden. Accessed September 24, 2020. https://www.folkhalsomyndigheten.se/contentassets/c1b78bffbfde4a7899eb0d8ffdb57b09/covid-19-school-aged-children.pdf
- Fontanet A, Grant R, Tondeur L. xSARS-CoV-2 infection in primary schools in northern France: a retrospective cohort study in an area of high transmission. Preprint. Posted online June 29, 2020. medRxiv 2020.06.25.20140178. doi:10.1101/2020.06.25.20140178 [CrossRef]
- Zhai P, Ding Y, Wu X, Long J, Zhong Y, Li Y. The epidemiology, diagnosis and treatment of COVID-19. Int J Antimicrob Agents. 2020;55(5):105955. doi:10.1016/j.ijantimicag.2020.105955 [CrossRef] PMID:32234468
- Andina D, Noguera-Morel L, Bascuas-Arribas M, et al. Chilblains in children in the setting of COVID-19 pandemic. Pediatr Dermatol. 2020;37(3):406–411. doi:10.1111/pde.14215 [CrossRef] PMID:32386460
- Feldstein LR, Rose EB, Horwitz SM, et al. Overcoming COVID-19 InvestigatorsCDC COVID-19 Response Team. Multisystem inflammatory syndrome in U.S. children and adolescents. N Engl J Med. 2020;383(4):334–346. doi:10.1056/NEJMoa2021680 [CrossRef] PMID:32598831