key: cord-0875797-cloqtudb
authors: Marais, Ben J
title: COVID-19 disease spectrum in children – first insights from Africa
date: 2020-11-14
journal: Clin Infect Dis
DOI: 10.1093/cid/ciaa1731
sha: e3dca466b08d79c15b1d2fdc0ef44776c8af6234
doc_id: 875797
cord_uid: cloqtudb

nan

M a n u s c r i p t 2 Although the morbidity and mortility observed among older people with SARS CoV-2 infection is high, a consistent observation has been the low risk of severe disease in children and young adults (1, 2) .

In fact paediatric intensive care units were often converted to accommodate adult patients in countries with major epidemic peaks that overwhelmed the healh care system, given the low numbers of children requiring intensive care compared to older adults. The pronounced age differential observed with severe COVID-19 disease is different to the experience with SARS or major influenza epidemics of the past and remains largely unexplained (1) .

Despite their relative protection against adverse outcomes, instances of severe disease in children do occur (3, 4) and it is important to better understand the risk profile of these children. In addition, disease rates in low and middle income countries (LMICs) with higher rates of childhood malnutrition Some form of respiratory support, mostly high flow nasal prongs oxygen, was required in nearly half (25/51; 49%) of the hospitalised children; of whom the majority (13/25; 52%) was younger than 3

A c c e p t e d M a n u s c r i p t 3 months of age. As has been the experience in other southern hemisphere settings where strict social distancing measures were in place throughout winter, total hospital admissions for respiratory infections were greatly reduced compared to historical averages. Despite the presence of SARS CoV-2 Tygerberg Hospital experienced a greater than 30% reduction in paediatric admissions due to respiratory infections during the study period, compared to the same period last year. This reflects the major impact that social distancing has had on the transmission of common respiratory viruses, with a concurrent reduction in secondary bacterial infections.

Among children admitted to ICU there was a high rate of virus co-infection, which is common in children with respiratory disease (7). This poses a major dilemma for cause attribution and Pneumocystis jiroveci pneumonia (PJP) until this has been excluded. In the absence of a compartor group it is impossible to assess the role that early steroid administration may have played to reduce disease severity. Diarrhoea and vomiting, as well as the rare multisystem inflammatory syndrome (MIS-C), was more common in older children and acute appendicitis was recognised as a potential gastro-intestinal presentation of SARS CoV-2 infection in this group (6, 9, 10) .

It is notable that a high percentage of children admitted to hospital (7/51; 13·7%) had a recent or new diagnosis of tuberculosis. Globally, the SARS CoV-2 pandemic has had a major detrimental impact on TB control efforts, mainly through reduced and delayed case detection and increased treatment A c c e p t e d M a n u s c r i p t 4 default caused by difficulties in health care access and treatment supervision (11) . Since more than 90% of children less than 3 months of age with severe COVID-19 received BCG vaccination, the authors concluded that this suggests lack of protective effect. The protective effect of BCG against COVID-19 remains highly contentious, but study observations do not provide new insight. Given that BCG induced immune responses are only activated 2-3 months after administration, the overrepresentaiton of children under 3 months of age among those with severe COVID-19 may suggest a protective effect rather than than the absence of a protective effect. However, given the myriad factors that increase vulnerability to severe infections in babies under 3 months of age it is important to guard against over-interpretation.

Returning to the pronounced age differential in COVID-19 disease vulnerability referred to earlier, it is interesting to review basic principles. It may be that young people are less likely to get infected with the virus, or that the virus is less likely to reach their lungs. From the available epidemiological evidence there is no indication that young children are less likely to become infected than older people,(12) although they may excrete the virus for a shorter period of time and unlike the situation with other respiratory viruses they contribute little to community spread (13) . The same cannot be said of younger adults with high levels of social contact who may contribute substantially to community transmission, although they are at low risk of disease development themselves (14) .

There is general consensus that primary SARS CoV-2 infection usually occurs in the upper airways.

Although aerosol transmission with direct lung infection can occur, this seems to be rare and most In general the report from South Africa contains good news about COVID-19 disease risk in HIVinfected and malnourished children, and supports observations that children are generally a low risk group. However, infants (especially those <3 months) hospitalized with SARS-CoV-2 frequently required respiratory support. The unavailability of continuous positive airway (CPAP) ventilation or even humidified oxygen via nasal prongs is a major concern in many LMICs, for optimal clinical management of severe COVID-19 and common childhood pneumonia (6, 15) . In children with severe COVID-19 there is also a need to better characterise longer term sequellae.

A c c e p t e d M a n u s c r i p t

Comparing SARS-CoV-2 with SARS-CoV and influenza pandemics

Pathways to COVID-19 'community protection'

COVID-19 in children and adolescents in Europe: a multinational, multicentre cohort study

Multisystem Inflammatory Syndrome in Children in New York State

Risk factors for mortality from acute lower respiratory infections (ALRI) in children under five years of age in low and middle income countries: a systematic review and meta-analysis of observational studies

Clinical experience with SARS CoV-2 related illness in children -hospital experience in Cape Town, South Africa

Community-acquired pneumonia requiring hospitalization among US children

Effect of Dexamethasone on Days Alive and Ventilator-Free in Patients With Moderate or Severe Acute Respiratory Distress Syndrome and COVID-19: The CoDEX Randomized Clinical Trial

Multisystem inflammatory syndrome in children in South Africa. The Lancet

Acute appendicitis in MIS-c and COVID-19

COVID-19 and Tuberculosis -threats and opportunities

Epidemiology and transmission of COVID-19 in 391 cases and 1286 of their close contacts in Shenzhen, China: a retrospective cohort study

Transmission of SARS-CoV-2 in Australian educational settings: a prospective cohort study

Optimising strategies to mitigate the impact of COVID-19 in the six most severely affected countries: a modelling study

Bubble continuous positive airway pressure for children with severe pneumonia and hypoxaemia in Bangladesh: an open, randomised controlled trial