The study determines the best time to get vaccinated against RSV during pregnancy

Pregnant women are recommended to be vaccinated against respiratory syncytial virus (RSV) to protect both themselves and their newborns who are too juvenile to be vaccinated. Current guidelines recommend the injection between the 32nd and 36th week of pregnancy, but is there an optimal time during this period that could further augment protection for the newborn?

RSV is a common respiratory virus that can cause sedate infections in older adults and juvenile children. US Centers for Disease Control and Prevention (CDC) recommends protecting infants against severe RSV with either the mother’s vaccine during pregnancy or a dose of antibodies for the baby.

Researchers in a recent study found that getting vaccinated earlier at the recommended date, closer to 32 weeks of age, may provide newborns with the best protection against RSV.

In earlier studies by the same team, researchers found that the timing of vaccination against Covid-19 during pregnancy may affect the mother’s immune response and the transfer of antibodies across the placenta to the fetus. The latest study examined how the timing of RSV vaccine administration affected 124 pregnant women who received the vaccine between 32 and 36 weeks of pregnancy. To find out the level of protection in the infants, the researchers also tested antibodies in the umbilical cords of 29 infants born to these mothers.

“Researchers found that maternal RSV vaccination at least 5 weeks before delivery led to the most effective transfer of maternal antibodies across the placenta to the newborn compared to maternal vaccination 2-3 or 3-4 weeks before delivery,” he added. press release he stated.

By comparing antibodies in maternal blood and cord blood after RSV vaccination with those of unvaccinated mothers, researchers found that vaccination led to significantly higher and longer-lasting levels of RSV antibodies in both mothers and their newborns.

“This work provides much-needed data that can assist physicians advise patients about the timing of RSV vaccination during pregnancy. Our findings suggest that earlier vaccination at the approved date allows for the most effective transfer of antibodies across the placenta to the newborn. They may also have implications for when the monoclonal antibody against RSV, nirsevimab, should be administered to newborns. Similar studies should be conducted for other vaccines administered during pregnancy,” senior author Dr. Andrea Edlow said in a press release.

Researchers say more research is needed to determine the minimum level of antibodies needed to protect infants against RSV and to understand the additional protection that breast milk provides from vaccinated mothers.