Representative photo: students wearing protective masks at a government school in Hyderabad, March 2020. Photo: Reuters/Vinod Babu
- Reopening schools is a complex task fraught with many challenges and uncertainties. At the same time, we can’t postpone reopening indefinitely.
- If children in general don’t experience serious illness due to SARS-CoV-2 infections, it means they have an inherent capacity to fight the virus.
- Scientific reports suggest that children are less susceptible to infection than adults, and when infected they are less likely to spread the virus to others.
Schools and colleges have started reopening across the country after a prolonged shutdown. Authorities neither at the national nor at state levels have articulated why they have permitted educational institutions to reopen now.
As a result, there are many unanswered questions in the minds of the general public, especially parents, teachers and older children, linked to school reopening: Why now? Does school reopening mean the pandemic is going away soon? Is it true that children are not affected much by SARS-CoV-2? Are schools not likely to turn into COVID-19 ‘hotspots’? Will it be necessary to vaccinate children? How are schools planning to ensure children’s safety?
Finding answers to many of these questions is not easy. This is because scientists are still in the process of understanding SARS-CoV-2, COVID-19 and the pandemic’s changing dynamics. Also, we don’t have the necessary and sufficient India-centric data on the COVID-19 burden among children.
Reopening schools is a complex task fraught with many challenges and uncertainties. At the same time, we can’t postpone reopening indefinitely. So let us examine the available data to arrive at some answers to guide our decision-making.
Why should schools reopen now?
The pandemic has wreaked irreparable damage to children’s education around the world, more so in poorer countries. UNICEF reports that the education of over 400 million children in South Asia has been disrupted.
It is also apparent now that remote-learning is seriously hamstrung by limited access to devices, low internet-connectivity and limited teacher contact. And of those able to access online learning, a significant fraction has reported poorer learning outcomes compared to in-person learning before the pandemic. A recent survey covering 15 states, conducted by noted economist Jean Drèze, provides some perspective: his team found that only 8% of rural children had access to online education while 37% had just given up.
We are also realising that prolonged school shutdowns don’t only impact the education and future of children and adolescents, but also affect their physical and mental well-being. With the pandemic well into its second year, and not knowing if and when it is going to end, world bodies like the WHO, UNICEF and UNESCO have urged countries to prioritise safely reopening schools as early as possible.
The consensus opinion that has emerged is that education is an obligatory and essential service and must be regarded as such. Therefore, countries, governments and communities owe it to their upcoming generations to find ways to reopen schools with appropriate safety measures in place, without waiting any longer.
Pandemic ebbing for now
India’s second COVID-19 outbreak, which peaked in early May 2021, has pretty much dissipated now, but is not totally gone. The ‘Our World in Data’ website shows that at the national level, COVID-19 cases in India, which were as high as 280 per million, have settled at about 20 cases per million in the third week of September.
Deaths have come down from three per million cases at the peak to about 0.2 per million, with the case fatality rate down from 3% to less than 1% at present. Based on the basic reproduction number, R0, the virus also appears to be spreading more slowly now.
During an outbreak, the first person who carries the infection into a community is designated as the primary case. People who get the infection from the primary case are known as secondary cases. R0 refers to the number of secondary cases that can be traced back to a single primary case. An R0 value of more than 1 indicates that the virus is spreading actively, while values less than 1 indicate that virus spread is slowing down. The R0 value is currently around 0.9, indicating that the epidemic is in control at present.
At this time, about 45% of India’s 940 million adults have received at least one dose of a COVID-19 vaccine as well.
Taken together, the epidemic seems to be receding in India and we can chart a path to normalcy. There are a few caveats, however. The epidemic is actually more complex than it appears, and its course is not amenable to accurate prediction. Many experts have pointed out that our COVID-19 metrics, especially the number of deaths during the pandemic, may have been seriously underestimated, for a variety of reasons. It follows that the R0 value derived from such data would not reflect the ground situation. In fact, the R0 value in the days preceding India’s massive second outbreak was lower than 1.
Next, the emergence of the delta variant last October has been a game-changer in the pandemic. In the early days of the pandemic, R0 for the ‘original’ SARS-CoV-2 strain was between 2 and 3, meaning a primary case passed on the infection to two or three secondary cases.
In reality, the spread happens in bursts, with a small number of infected individuals passing on the virus to large clusters of people, usually in crowded places. A preprint paper posted online last month reported the R0 of the delta variant to be 6.4. This means the delta variant is at least twice as effective at spreading, and can seed large clusters.
The delta variant has also been found to be able to cause fever and illness more rapidly (in about three days), which is often before the body can mount an immune response. This has enabled the delta variant to outpace other variants, making it the predominant driver of the pandemic today.
The delta variant is also able to break through the ‘shield’ of protection of vaccinated individuals. We need to remember that all the COVID-19 vaccines were tested against the ‘original’ strain of the novel coronavirus, not against the delta variant. While these vaccines have been able to blunt the severity of breakthrough infections, they do not stop these vaccinated individuals from spreading the virus.
This means unvaccinated individuals can catch the delta variant from other vaccinated people experiencing breakthrough infections, if they fail to observe masking and social distancing practices, and then pass them on to yet others. We must remember that children – both in India and around the world – represent a significant fraction of the unvaccinated population.
Children don’t escape
An extensive contact-tracing effort in Tamil Nadu and Andhra Pradesh in the first four months of the pandemic reported that children of all ages get infected with and spread SARS-CoV-2 to others. This is consistent with recent serological surveys conducted in April-July this year, at the local and national levels. These surveys reported that 50-60% of children (<18 years) had been exposed to SARS-CoV-2. Considering that the delta variant has been dominant in the country for most of 2021, it is likely that all these children had been exposed to this variant. None of these surveys provided any information on any illnesses that any of these children may have experienced.
According to the US Centres for Disease Control and Prevention, children in general are not affected much by SARS-CoV-2. Upon infection, they may not show any symptoms (asymptomatic) or may suffer a mild illness. But some children can experience severe COVID-19, especially if they have comorbidities. Some children may also develop a rare but serious inflammatory immune condition called multisystem inflammatory syndrome in children (MIS-C), several weeks after being exposed to the virus.
The delta surge that occurred recently in the US has been linked to a rise in MIS-C, mostly among Hispanic/Latino and non-Hispanic Black children. As of August 2021, the CDC documented more than 4,600 MIS-C cases in 5-3-year olds, with a fatality rate of 1%. Apparently, MIS-C has also affected children in India during the second wave, but there is no precise documentation of these cases.
In countries like Israel, the US and the UK, which have fully vaccinated more than half of their adult populations, the highly transmissible delta variant is now making COVID-19 a disease of the unvaccinated, of which children younger than 18 years constitute a significant chunk. India has not yet achieved the vaccination levels of these countries, and a significant fraction of its children are exposed to the virus.
It is clear that children do get infected by SARS-CoV-2, perhaps at rates comparable to adults. Are children more susceptible to the delta variant? Is there a definitive link between ethnicity of children and their susceptibility to the virus? These questions we have not been able to answer so far.
A robust innate immunity
If children in general don’t experience serious illness due to SARS-CoV-2 infections, it means they have an inherent capacity to fight the virus. How do they do it?
The inner lining of the nose (nasal epithelium) is one of the first sites of infection. The virus finds and attaches to an enzyme called angiotensin-converting enzyme 2 (ACE2), present on the outer surface of cells of this nasal lining. ACE2 serves as a SARS-CoV-2 receptor. One hypothesis to explain children’s resilience to SARS-CoV-2 infection is that children have fewer ACE2 receptors than adults in the nasal epithelium. This means children would be exposed to a lower amount of viral particles and will therefore not experience serious illness.
Two groups of scientists, one in the US and the other in Germany, tested the levels of ACE2 receptors in the nasal epithelium of children and adults, but obtained contradictory results. One critical difference between the work of the American and German scientists was that the former used frozen samples, collected a year or earlier before the pandemic started – while the latter collected samples for analysis from both healthy and infected children and adults during the pandemic.
This controversy may perhaps be resolved by an ongoing study, involving a large number (>5,000) of children and adults, designed to quantitatively correlate ACE2 levels to SARS-CoV-2 infection rates.
New insights have also come from the work of the same group of German scientists. In addition to ACE2, they also examined the status of the innate immune system in the nasal epithelium of healthy and infected children and adults.
Recall the high-school biology lesson on the functioning of our immune system. When we get infected by any disease-causing agent, known as a pathogen, the immune system mounts an early non-focused response, followed later by a pathogen-focused specific response. The early response, known as the innate immune response, relies on special molecules that act as sensors capable of recognising pathogen-associated molecules and their patterns. The innate immune system springs to action when such a sensor ‘senses’ an intruder.
The result is the production of certain proteins that strongly interfere with and suppress virus multiplication at multiple levels. These interfering proteins are known as interferons. Switching ‘on’ the innate immune response paves the way to activate the focused response, known as the adaptive (or acquired) immune response. This acts through the production of antibodies that specifically attack the particular intruder, and specialised immune cells (known as T cells) that eliminate infected cells.
The German team’s study found that the nasal epithelium of healthy children – but not adults – happen to have high levels of a molecule known as MDA5, which turns out to be a major innate immune sensor of SARS-CoV-2. As soon as MDA5 senses SARS-CoV-2 in the nasal epithelium, it triggers a massive interferon surge to suppress the virus from multiplying. The German scientists also found evidence of certain immune cells – dendritic cells and macrophages – in the nasal epithelium of children in a heightened state of alertness.
Altogether, the innate immune system of children appears to be primed and ready to tackle SARS-CoV-2 from the get-go. Adults don’t have these advantages: their innate immune system is slower to respond. Scientists in the US have also uncovered evidence that SARS-CoV-2 may exploit this time lag to interfere with the function of interferons.
Of course, these factors by themselves are unlikely to account for the different extents to which children and adults seem to be susceptible to COVID-19. The innate and adaptive immune systems are functionally interconnected and there are likely other players contributing to defending against the virus.
At this time, there is not much information concerning the adaptive immune system response to SARS-CoV-2 in children versus adults. All children are not uniformly susceptible to the virus. Studies of school children in Germany and the US have shown that there is an age-wise gradation in susceptibility, too. The younger children (5-11 years old) appear to be less likely to be affected compared to the older ones (12-17 years old).
Schools as possible hotspots
Our schools have largely been shut for the one-and-half years. Do we expect to see a surge of infections in children as they return to schools? To address this question, we may draw from the experiences of schools in Europe and the US, which reopened during the pandemic. Note that any information we glean from them should be tempered by the fact that these school-reopening experiences predate the arrival of the highly transmissible delta variant, and also acknowledge the socioeconomic and cultural differences between settings in India versus those in the ‘developed’ world.
In September 2020, when its caseload was climbing, Italy reopened its schools. A month later, about 1,200 of 65,000 schools reported outbreaks. In a majority (93%), there was only a single infection. This means the spread of the virus was very low in these schools.
The public health agency of England conducted a month-long national survey of SARS-CoV-2 transmission in schools when they reopened in June 2020. It found that infections and outbreaks were rare in schools. And in these rare instances, the staff members seemed to be at increased risk of infection.
A US study monitored more than 90,000 students and staff who attended schools in person in North Carolina over two months, from mid-August 2020. This study, published in January 2021, found through contact-tracing exercises that only 32 infections were acquired on school premises, with no instances of child-to-adult spread of COVID-19. Similarly low transmission rates in schools have been reported from New York and Utah.
But did these studies miss out cases of asymptomatic infection and underestimate the spread of the virus? That COVID-19 spread in school settings is indeed low, even after accounting for asymptomatic children, is evident from a study conducted in Norway. Here, investigators identified about a dozen primary school children who had contracted SARS-CoV-2 infections, followed up on their children and adult contacts, and tested them. They found that child-to-child and child-to-adult spread was less than 1% and 2%, respectively.
These reports, as well as another analysis, suggest that children are less susceptible to infection than adults, and when infected they are less likely to spread the virus to others. Clearly, schools did not serve as COVID-19 hotspots in these instances. It is important to note that the children in the aforementioned studies were not in a typical school environment, but in an environment following COVID-appropriate protocols and behaviour.
Can the experience of schools abroad apply to Indian schools? Israel’s case may be instructive, and in fact offers an important pointer: the country reopened its schools, (which are usually crowded and don’t allow for adequate physical distancing) in mid-May 2020, with some preventive measures.
With summer temperatures climbing to 40º C and beyond, the government briefly exempted the need for face-masks and allowed air-conditioners to operate. Subsequently, an outbreak that started with two confirmed cases of COVID-19 in one of its schools spread to a total of 260 individuals, including students, staff and family members. Fortunately, most were asymptomatic.
Is it because of children’s innate capacity to ward off COVID-19? Is it because the delta variant hadn’t yet arrived in the country? Definitive answers to these questions are lacking.
The high population density in our country, especially in cities like Mumbai and Delhi, make physical-distancing a big challenge. Children need to negotiate these highly populated spaces as they travel between their homes and schools. With the delta variant driving the pandemic now, children are likely to be exposed to the virus and schools can very well be COVID-19 hotspots.
What should schools do to protect children from safety risks, while ensuring that they do not lose out on their education?
Challenges and uncertainties
The typical scenes we witness today, with most people unmasked and jostling in crowded streets, markets and other public spaces, convey an illusory sense of normalcy. This ends up encouraging many others, who are not sure if they must indeed exercise caution, and the uninformed to drop their guard.
The reality is that the pandemic has not ended, but we don’t know how it is going to play out. Lack of effective ways of public messaging to make people internalise this reality, and be responsive and responsible, is a big challenge.
India has thus far administered at least one dose of a COVID-19 vaccine to about 45% of its eligible adult population. This leaves about 520 million adults still to be vaccinated. Add the 460 million or so people younger than 18 years, and India alone has nearly a billion unvaccinated people at this time.
The country is currently reporting new COVID-19 cases daily of about 30,000, most of whom are likely to be afflicted by the delta variant. With about a billion unvaccinated people in the country, this live spark of a virus can rapidly trigger a bigger conflagration, particularly in the face of low or no adherence to COVID-appropriate behaviour.
Such a surge could exact a huge public health cost as well as provide an ideal breeding ground for new, and perhaps more worrisome, variants to emerge in the future. We also have no way to predict if a new variant will turn out to be more or less dangerous than the delta variant.
Experts in the developed world have argued that rapidly vaccinating all adults may serve to shield children from the virus. This view conflicts with the experiences of countries with high adult vaccination coverage seeing more of their children get infected as well. Nevertheless, many countries advocate child vaccination and several have already started administering COVID-19 vaccines to their children.
COVID-19 vaccines for children are being tested in India and expected to be launched in the near future. However, note that other countries vaccinating their children does not offer a rationale to vaccinate children in India, especially when answers to many critically relevant questions are not available. Some include: What is the actual burden of COVID-19 in children, in terms of disease severity and mortality? And how safe will the vaccines be among children, especially in the long-term?
What should schools do?
Given all these challenges and uncertainties, how are schools to reopen safely and resume uninterrupted education of children? UNICEF has provided some guidelines to this effect.
First: schools must change to offer a hybrid mode of education, using both offline and online modes. Reopening must implement all reasonable measures to ensure students, teachers, staff and all their families are protected. Schools also need to ensure safe operations focused on risk-mitigation measures, physical distancing, sanitation and hygiene, and have the capacity to actively monitor health indicators.
Second: Underprivileged children need to be prioritised for in-person learning. Children from higher economic strata could be offered online classes. For this, schools must strengthen remote-learning and enhance its quality to make it more practical (including in terms of adhering to physical distancing), integrate out-of-school children, and at the same time ensure better online-learning.
To enable schools to implement these activities, they must have assured funding and policy guidance from local and national educational authorities.
S. Swaminathan is a retired scientist based in Hyderabad. The views expressed here are the author’s own.