Long COVID symptoms in families a year after SARS-CoV-2 infection or household exposure

By Dr. Liji Thomas, MDMar 10 2022Reviewed by Danielle Ellis, B.Sc.

Scientists have reported that, typically, children and adolescents are asymptomatically, mildly, or moderately infected by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causal agent of the current coronavirus disease 2019 (COVID-19) pandemic. Therefore, these groups are considered to be at a lower risk of contracting acute COVID-19 infection.

*Important notice: Preprints with The Lancet publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.

Background

Recently, terms such as “post-COVID syndrome,” “long COVID,” or “post-acute sequelae of COVID-19 (PASC)” have been frequently used to describe the persistence or emergence of various symptoms, ranging from fatigue to specific organ dysfunction, long after recovering from SARS-CoV-2 infection. The majority of studies have defined long COVID as a condition when COVID-19 infected adults exhibit symptoms 3 to 6 months after acute illness.

The pandemic has reduced social interactions because of travel restrictions and the closure of schools and nurseries. Scientists have revealed that limited interactions have considerably impacted children and adolescents. They observed an increased prevalence of non-specific and psychological symptoms in children and adolescents who never contracted COVID-19 infection. Therefore, it is important to distinguish between the symptoms of long COVID from the general consequences of the pandemic.

Not much evidence is available regarding the possible long COVID symptoms in children and adolescents. The studies related to long COVID are mostly associated with individual-level risk factors, and they do not consider the disease dynamics within families. Previous studies reported the occurrence of various pediatric conditions, such as chronic pain and fatigue, to be related to parents’ symptoms, stress, and/or parenting behavior. Thereby, scientists believe families could also play a role in long COVID symptomatology.

A new study

A new study posted to Preprints with The Lancet* has analyzed symptoms up to one year of post-acute COVID-19 infection. Researchers conducted a reverse transcription-polymerase chain reaction (RT-PCR) test and serology analysis in families who participated in another study of SARS-CoV-2 transmission within households with children. As stated above, family context might have an important association with the prevalence of long COVID. Scientists took advantage of this study cohort and determined that the prevalence of reported symptoms was associated with reported symptoms amongst family members.

This study consisted of 1267 members from 341 households, which included 404 children above the age of fourteen, 140 adolescents (14-18 years), and 723 adults. The authors categorized these candidates based on serological assays and history of laboratory-confirmed infection. They were categorized into two groups, i.e., participants directly infected with SARS-CoV-2 and participants exposed to SARS-CoV-2 indirectly through an infected household member.

Key findings

Scientists revealed the family context of prolonged symptoms following SARS-CoV-2 infection, and the findings were in line with previous reports that showed that infected adults were more likely to experience worse health outcomes, such as fatigue and a range of persistent physical and psychological symptoms, compared to exposed adults.

Interestingly, negative outcomes were also relatively common amongst the exposed non-infected adults, which persisted for about a year after being exposed to SARS-CoV-2 patients. However, the exposed adults revealed negative SARS-CoV-2 serological assays. These results indicate the prevalence of nonspecific symptoms among COVID-19 exposed household members.

Researchers observed the prevalence of moderate to severe symptoms persist after one year of infection in men, women, and adolescent girls. They reported that individuals with symptomatic SARS-CoV-2 infection were more inclined to develop long COVID, compared to individuals with asymptomatic infection. Two of the common long COVID symptoms were acute diarrhea and dysgeusia.

Scientists reported that compared to men, women were more prone to develop persistent symptoms, such as moderate or severe fatigue, sleep disruption, and reduced physical resilience. However, both genders experienced moderate or severe dysgeusia/dysosmia, as long COVID symptoms. Interestingly, gender differences were also present in the exposed control group, where 14·2% of exposed women and 10·3% of exposed men reported at least one moderate or severe symptom.

As adolescent girls were more prone to develop long COVID than adolescent boys, more research is required to elucidate the risk factors and treatment strategies. Another significant finding of this study was determining the correlation between the number of moderate or severe persistent symptoms (in both exposed and infected individuals) and the number of moderate or severe persistent symptoms in other household members. There are many plausible explanations for this correlation, including shared genetic factors.

Conclusion

One of the main strengths of this study is the study cohort, which included individuals with mild or asymptomatic disease, i.e., a good representation of the majority of SARS-CoV-2 infections. Another important aspect is that both infected and exposed groups belonged to the same families, which enabled an excellent match with regards to socio-demographic and environmental factors.

One key limitation of this study is the small sample size, especially the adolescent group. However, the findings of this study are in line with a recent meta-analysis that showed that prolonged symptoms are prevalent in both infected as well as exposed children. The authors of this study stated that more research is required to understand family-level mechanisms and interventions in long COVID.

*Important notice: Preprints with The Lancet publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.