COVID-19 vaccination in children and adolescents aged 5 years and older undergoing treatment for cancer and non-malignant haematological conditions: Australian and New Zealand Children's Haematology/Oncology Group consensus statement

COVID-19 infection in children with blood cancer: A systematic review

BACKGROUND

Blood cancer is the most common type of cancer and the leading cause of death by disease past infancy among children. Children with blood cancer are vulnerable population to viral infections such as coronavirus disease 2019 (COVID-19).

OBJECTIVES

To estimate the incidence of COVID-19 in children with blood cancer and analyse the demographic parameters, clinical characteristics and treatment outcomes in children with blood cancer with COVID-19 illness.

METHODS

We adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline and searched ProQuest, Medline, Embase, PubMed, CINAHL, Wiley online library, Scopus and Nature for studies on the development of COVID-19 in children with blood cancer, published from December 1, 2019 to April 30, 2023, with English language restriction.

RESULTS

Of the 3077 papers that were identified, 155 articles were included in the systematic review (83 case report, 54 cohort and 18 case-series studies). Studies involving 1289 children with blood cancer with confirmed COVID-19 were analysed. Leukaemias (1141 cases) were the most frequent types of blood cancer observed in children who developed COVID-19, followed by non-Hodgkin's lymphomas (59 cases), Hodgkin's lymphomas (36 cases), Langerhans cell histiocytosis (7 cases), myelodysplastic syndrome (7 cases) and myeloid neoplasm (1 case). Among all 1289 blood cancer paediatric cases who transmitted severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), some children were documented to be admitted to the intensive care unit (ICU) (n = 175, 13.6%), intubated and placed on mechanical ventilation (MV) (n = 111, 8.6%), suffered acute respiratory distress syndrome (ARDS) (n = 144, 11.2%) or died (n = 111, 8.6%). Overall, COVID-19 in children with different types of blood cancer resulted in no or low severity of disease in 78.6% of all included cases (COVID-19 severity: asymptomatic = 238, mild = 601, or moderate = 171). Treatment for COVID-19 was not necessary in a small number of children with blood cancer (n = 94, 7.3%). Fatality in children with blood cancer with COVID-19 was reported in any of the included blood cancer categories for leukaemias (n = 99/1141, 8.7%), non-Hodgkin's lymphomas (n = 7/59, 11.9%), Hodgkin's lymphomas (n = 2/36, 5.5%), myelodysplastic syndrome (n = 1/7, 14.3%) or myeloid neoplasm (n = 1/1, 100%). Fatality rate in children with blood cancer infected with SARS-CoV-2 was the highest in patients with Hispanic ethnicity (n = 44/111, 39.6%) and COVID-19-related fatality was highest in male patients (76.5% of deceased patients). Most studies reported to alter the intensity and regimen of anticancer treatment in children with blood cancer during course of SARS-CoV-2 infection, however, many studies have reported to successfully treat COVID-19 without any changes to the anticancer treatment.

CONCLUSION

Globally, leukaemias were the most prevalent and myeloid neoplasms were the least prevalent blood cancer types in children who developed SARS-CoV-2 infection. Children with blood cancer infected with SARS-CoV-2 may experience higher rates of ICU admission and mortality in comparison with the healthy pediatric populations. Mortality in children with blood cancer and infected with SARS-CoV-2 was highest in cases belonging to male gender and Hispanic ethnicity. However, children with blood cancer tend to have milder COVID-19 symptoms and are less likely to be hospitalized and have better prognosis when compared to adults. Continuation of anticancer treatment in individual paediatric blood cancer patients with COVID-19 seems to be possible.

Safety and efficacy of COVID-19 vaccines in children and adolescents with cancer

BACKGROUND

Children with cancer have a higher morbidity and mortality due to COVID-19. Vaccination of children with cancer is important. In this study, we aimed to investigate the effectiveness and side effects of the COVID-19 vaccines in children and adolescents with cancer.

METHODS

Fifty-eight patients from four centers were included in the study. Antibodies to the SARS-CoV-2 spike protein levels were measured. Vaccine-related complaints were recorded.

RESULTS

There were 33 male and 25 female patients. The mean age was 16.9±2.3 years. In 58.6% of cases, the diagnosis was hematological malignancies. Twenty patients were currently under treatment, while 38 had completed the treatment. Forty-eight patients received chemotherapy ± radiotherapy, 13 received immunotherapy, and 3 underwent stem cell transplantation. CoronoVac© and BNT162b2© vaccines were administered in 24% and 76%, respectively. The mean antibody level was lower in patients who received CoronaVac© than that of BNT162b2©, although the difference was not significant. The levels were within the protective limits in both groups. No significant difference was found in antibody levels according to diagnostic subgroups, treatment status, type of treatment, line of treatment, disease status and time between vaccines and measurement of antibody level. The most common side effects were pain at the injection site (37.9%) and malaise/weakness (17.2%), which were similar for both vaccines.

CONCLUSIONS

Our study showed that both mRNA and inactivated vaccines elicit an immune response in children with cancer. However, the seroconversion rate is significantly higher in mRNA vaccines. Side effects were similar to those seen in healthy children.

Impact of COVID-19 in pediatric oncology care in Latin America during the first year of the pandemic

BACKGROUND

The ongoing coronavirus 2019 disease (COVID-19) pandemic strained medical systems worldwide. We report on the impact on pediatric oncology care in Latin American (LATAM) during its first year.

METHOD

Four cross-sectional surveys were electronically distributed among pediatric onco-hematologists in April/June/October 2020, and April/2021 through the Latin American Society of Pediatric Oncology (SLAOP) email list and St Jude Global regional partners.

RESULTS

Four hundred fifty-three pediatric onco-hematologists from 20 countries responded to the first survey, with subsequent surveys response rates above 85%. More than 95% of participants reported that treatment continued without interruption for new and active ongoing patients, though with disruptions in treatment availability. During the first three surveys, respondents reported suspensions of outpatient procedures (54.2%), a decrease in oncologic surgeries (43.6%), radiotherapy (28.4%), stem cell transplants (SCT) (69.3%), and surveillance consultations (81.2%). Logistic regression analysis showed that at the beginning of the first wave, participants from countries with healthcare expenditure below 7% were more likely to report a decrease in outpatient procedures (odds ratio [OR]: 1.84, 95% CI: 1.19-2.8), surgeries (OR: 3, 95% CI: 1.9-4.6) and radiotherapy (OR: 6, 95% CI: 3.5-10.4). Suspension of surveillance consultations was higher in countries with COVID-19 case fatality rates above 2% (OR: 3, 95% CI: 1.4-6.2) and SCT suspensions in countries with COVID-19 incidence rate above 100 cases per 100,000 (OR: 3.48, 95% CI: 1.6-7.45). Paradoxically, at the beginning of the second wave with COVID-19 cases rising exponentially, most participants reported improvements in cancer services availability.

CONCLUSION

Our data show the medium-term collateral effects of the pandemic on pediatric oncology care in LATAM, which might help delineate oncology care delivery amid current and future challenges posed by the pandemic.

Answers to common questions about COVID-19 vaccines in children with cancer

BACKGROUND

The SARS-CoV-2 outbreak in 2020 evolved into a global pandemic, and COVID-19 vaccines became rapidly available, including for pediatric patients. However, questions emerged that challenged vaccine acceptance and use. We aimed to answer these questions and give recommendations applicable for use in pediatric patients with cancer by healthcare professionals and the public.

METHODS

A 12-member global COVID-19 Vaccine in Pediatric Oncology Working Group made up of physicians and nurses from all world regions met weekly from March to July 2021. We used a modified Delphi method to select the top questions. The Working Group, in four-member subgroups, answered assigned questions by providing brief recommendations, followed by a discussion of the rationale for each answer. All Working Group members voted on each recommendation using a scale of 1 to 10, 10 being complete agreement. A "pass" recommendation corresponded to an agreement ≥7.5.

RESULTS

We selected 15 questions from 173 suggested questions. Based on existing published information, we generated answers for each question as recommendations. The overall average agreement for the 24 recommendations was 9.5 (95% CI 9.4-9.6).

CONCLUSION

Top COVID-19 vaccine-related questions could be answered using available information. Reports on COVID-19 vaccination and related topics have been published at record speed, aided by available technology and the priority imposed by the pandemic; however, all efforts were made to incorporate emerging information throughout our project. Recommendations will be periodically updated on a dedicated website.