Estimated impact of maternal vaccination on global paediatric influenza-related in-hospital mortality: A retrospective case series

Abstract

Background: Influenza virus infection is an important cause of under-five mortality. Maternal vaccination protects children younger than 3 months of age from influenza infection. However, it is unknown to what extent paediatric influenza-related mortality may be prevented by a maternal vaccine since global age-stratified mortality data are lacking. Methods: We invited clinicians and researchers to share clinical and demographic characteristics from children younger than 5 years who died with laboratory-confirmed influenza infection between January 1, 1995 and March 31, 2020. We evaluated the potential impact of maternal vaccination by estimating the number of children younger than 3 months with in-hospital influenza-related death using published global mortality estimates. Findings: We included 314 children from 31 countries. Comorbidities were present in 166 (53%) children and 41 (13%) children were born prematurely. Median age at death was 8¢6 (IQR 4¢5À16¢6), 11¢5 (IQR 4¢3À24¢0), and 15¢5 (IQR 7¢4À27¢0) months for children from low-and lower-middle-income countries (LMICs), uppermiddle-income countries (UMICs), and high-income countries (HICs), respectively. The proportion of children younger than 3 months at time of death was 17% in LMICs, 12% in UMICs, and 7% in HICs. We estimated that 3339 annual influenza-related in-hospital deaths occur in the first 3 months of life globally. Interpretation: In our study, less than 20% of children is younger than 3 months at time of influenza-related death. Although maternal influenza vaccination may impact maternal and infant influenza disease burden, additional immunisation strategies are needed to prevent global influenza-related childhood mortality. The missing data, global coverage, and data quality in this study should be taken into consideration for further interpretation of the results. Funding: Bill & Melinda Gates Foundation.

Acceptance and uptake of vaccines against tetanus, influenza, pertussis, and COVID-19 among pregnant and postpartum women in low- and middle-income countries: a systematic review and meta-analysis protocol.

“…A recent prospective cohort research also revealed that pregnant women who were infected with in uenza during pregnancy were more likely to have adverse pregnancy outcomes, such as late pregnancy loss and a reduction in their infants' birthweight when compared to women who were not infected [7,[9][10][11][12]. Additionally, acute lower respiratory infection (ALRI) caused by the in uenza virus is a leading cause of death in children under the age of ve [13,14]. In 2018, in uenza was linked to 15,300 in-hospital deaths in children under the age of ve worldwide [13,14].…”

“…Additionally, acute lower respiratory infection (ALRI) caused by the in uenza virus is a leading cause of death in children under the age of ve [13,14]. In 2018, in uenza was linked to 15,300 in-hospital deaths in children under the age of ve worldwide [13,14]. More than a third of in-hospital deaths were in children under the age of six months, with the majority (82%) occurring in low-income and lower-middle-income nations (LMICs).…”

“…More than a third of in-hospital deaths were in children under the age of six months, with the majority (82%) occurring in low-income and lower-middle-income nations (LMICs). When compared to older children in high-income countries (HICs), children under the age of six months had greater rates of in uenza-related hospitalization and mortality [13,14]. Infants can be protected early in infancy if their mothers are vaccinated [13,14].…”

“…When compared to older children in high-income countries (HICs), children under the age of six months had greater rates of in uenza-related hospitalization and mortality [13,14]. Infants can be protected early in infancy if their mothers are vaccinated [13,14]. Bordetella pertussis is what causes the pertussis infection, also known as whooping cough, a highly contagious disease of the respiratory tract [15][16][17].…”

“…The advantages of vaccination during pregnancy for infants were revealed for the rst time in 1879 when it was discovered that babies born to mothers who had received the vaccinia virus vaccine during pregnancy were protected from smallpox during the early period of their life [14,30,31]. Neonatal vaccination is an alternate method for protecting young infants from infectious diseases.…”