Leading experts discuss the burden of respiratory syncytial virus in infants and the role of early prevention at a seminar in Hà Nội on July 26. — VNS Photo Thanh Hải

HÀ NỘI — Health experts discussed the burden of respiratory syncytial virus (RSV) in infants and called for a greater focus on early prevention at a seminar in Hà Nội on Sunday.

The event, entitled 'Care Strategies For Pregnant Women: Proactive Mothers - Protected Infants', was jointly organised by the Vietnam Association of Gynaecology and Obstetrics (VAGO) and Pfizer Vietnam.

The seminar brought together leading experts in obstetrics, gynaecology, and paediatrics to discuss the protection gap during an infant's first six months of life against RSV, while highlighting the role of proactive antenatal care in supporting protection for infants.

In his opening remarks, VAGO President and Professor Nguyễn Viết Tiến said: “In recent years, antenatal care has evolved beyond monitoring foetal development to increasingly focus on preventing health risks that may affect children after birth, including those associated with RSV. 

"This approach is also reflected in newly updated professional guidelines, which aim to standardise clinical practice and support healthcare professionals in delivering proactive, preventive antenatal care for the long-term health and well-being of both mothers and their babies."

At the event, experts said that RSV is one of the leading causes of lower respiratory tract infections in children, associated with 1.4 million hospitalisations and 27,300 deaths in infants under six months.

In Việt Nam, data from paediatric hospitals show that RSV accounts for approximately 24–48 per cent of lower respiratory tract infections in children. Research conducted at the Việt Nam National Children's Hospital indicates that the disease burden is mainly concentrated in infants under three months (42.7 per cent), followed by those aged three to six months.

According to experts, this period creates an 'immunity gap' during the first six months of life because infants' immune systems are not fully developed and their airways are small. Additionally, small airways make infants more susceptible to inflammation, oedema and obstruction caused by RSV, while their bodies lack sufficient antibodies to fight off the virus, leading to a higher risk of being severely affected by RSV.

Preterm infants and those with congenital heart disease, chronic lung disease or weakened immune systems are recognised as being at higher risk of developing severe RSV disease. However, that concern should not be limited only to these high-risk groups alone, as RSV can still cause severe illness in all young children.

Associate Professor Nguyễn Thị Diệu Thúy, head of the Department of Paediatrics at Hà Nội Medical University, said that the majority of infants requiring treatment in the intensive care unit (ICU) for RSV-associated lower respiratory tract infections were born at term and were previously healthy. Data show that approximately eight in 10 infants (81.2 per cent) requiring ICU treatment due to RSV had no underlying medical conditions.

“Being healthy does not mean a child is safe from RSV. Many children may initially present with just a cough, runny nose or shortness of breath, but their conditions can rapidly progress to bronchiolitis and respiratory failure, requiring respiratory interventions such as mechanical ventilation or endotracheal intubation. 

"Parents should thus not be complacent and need to take early preventive measures rather than waiting until the child falls ill," Thúy said.

Thúy added that children with RSV infection often experience longer hospital stays, have a higher likelihood of requiring ICU admission, and are more likely to need intensive medical interventions. Furthermore, RSV infection has been associated with increased risk of long-term respiratory complications in young children, such as recurrent wheezing, asthma or impaired lung function.

The management of RSV disease remains primarily supportive, focusing on symptom control and respiratory support. Experts thus emphasised the need to shift the focus toward early prevention through a comprehensive approach that begins during pregnancy.

Protecting infants against infectious respiratory diseases requires a combination of appropriate care and preventive measures throughout pregnancy and after birth, including regular antenatal care, adequate nutrition, medical counselling, and maternal immunisation.

During pregnancy, the maternal immune system undergoes physiological adaptations that both help protect the mother against infectious diseases and support the healthy development of the foetus. 

Through the natural transfer of maternal antibodies across the placenta, particularly during the third trimester, a foetus can receive passive antibodies before birth. These provide early protection while the infant's own immune system is still immature, particularly during the first six months of life, when infants experience the immunity gap.

Executive Committee Member at the Việt Nam Society of Sexual Medicine Ngô Thị Yên said: “During the final months of pregnancy, a mother passes on part of her antibodies to her baby, so that from the baby's very first breath, he or she already carries a degree of protection against RSV.  

"It is this protection passed from mother to child during this critical period that helps narrow the protection gap in the first six months of life, when a baby's immune system is still immature and not yet able to protect itself."

At the roundtable, experts expressed their hope that pregnant women and their families will gain a more comprehensive, evidence-based understanding of respiratory health risks in young children, particularly RSV and the immunity protection gap during the first six months of life, enabling them to engage in informed discussions with their doctors about appropriate care options during pregnancy and after childbirth.— VNS