A new vaccine against bronchiolitis has just been authorized in Luxembourg. It is administered during pregnancy.
AprAnds l’arrivedReleased from Beyfortus® (monoclonal antibody) in 2023, a new vaccine intended for pregnant women now strengthens prevention strategies against Respiratory Syncytial Virus (RSV or RSV in French).ais). The ABRYSVO vaccine®, developed by Pfizer and rrecently approved in Luxembourg, is an inactivated protein vaccine bivalent. Unlike Beyfortus®, which acts by directly administering antibodies to newborns, this vaccine is based on another mechanism: vaccinating the mera from the 32ndmy week of pregnancy. This will produce antibodies that’she will transmit to son bthat’s it via the placenta, the protgrowing thus during its first months of life. This vaccine will be available from September. Talk to your gynecologist.
In April 2024, the Higher Council for Infectious Diseases (CSMI) issued new directives aimed at strengthening protection infants against RSV. These recommendations recommend a double stratumgie: either l’administration du Beyfortus© (Nirse-vimab) to infants, a monoclonal antibody already employborn after the lastAndre RSV epidemic (2023-2024), i.e. the possibility to vaccinate pregnant women. These measures are intended to provide seasonal protectionAndre optimal for newborns and small infants during the period of circulation of RSV, from September to February.
Why a dual strategy?
Dr Isabel De La Fuente, mchief physician of the Pediatrics department of the CHL and doctordecking spspecialized in infectious diseases: “A double stratumgie is indeed essential for ensure complete protectionAndyou and continue against RSV. It is based on three main reasons:
• There are situations wherewhere the RSV vaccinen’is currently not yet recommended (due to lack of data) and ou le Beyfortus© is for its partligible
– Multiple pregnancies
– Pregnancies at risk of’pre childbirthmatureand
– Non-physiological pregnancies with mAndres presenting comorbiditandyes (diabete, high blood pressure, etc.);
• This dual strategy makes it possible to better manage thes unforeseen events linked to difficulties’supply of vaccines, such as stock-outs or problemsAndmy delivery.
• Some children trAnds fragile (with unstable heart disease, cystic fibrosis, oxygandnothhome therapy, etc.) are eligible for protection against RSV also during the secondAndth year of life and will require an injection of Beyfortus© during their 2Andth season of RSV circulation (because both the vaccine during pregnancy and’Beyfortus injection© during the 1era annlife will not protect against’infection to RSV only for a periodof the limited several months).“
Vaccination of pregnant women against RSV: what to remember
The ABRYSVO© vaccine, available in Luxembourg since August 2024, can now be administeredto future mothers to protect babies born leave of September.
Who is eligible?
All future mothers in good health, whose pregnancy is progressing harmoniously and whose’childbirth is planned between September and February, may get vaccinatedit’s the 32ndmy week of pregnancy (and up to 36 weeks of pregnancy).
Why only from the 32nd week?
Dr De La Fuente explains this choice of the Higher Council for Infectious Diseases, of which she is a member: “We prioritized safety. In terms of safety profile, the results of the studies carried out on the RSV vaccine were overall very good.very reassuring. A major study, called “Matisse”, which included more than 3,000 women in a randomized controlled trial, did not demonstrate malformations in newborns or statistically significant adverse events. However, although not statistically conclusive, a slight increase in premature births has been observed in a specific population, notably in middle-income countries. This approach in the vaccination protocol therefore aims to avoid the period when the risk of premature birth is higher.thus ensuring a very safe vaccination program. In the future, with the accumulation of new post-marketing vaccine safety data (e.g. from the United States), it is likely that in Luxembourg, vaccination will one day be recommended earlier in pregnancy, i.e. that is to say from the 24th week of amenorrhea.”
How does the vaccine work and what are its benefits?
Unlike the Beyfortus treatment©, admindirectly to the baby for almost immediate protectiondiate, the ABRYSVO vaccine®, classic and without adjuvant, is an inactivated protein vaccine injected this time into the mera.
The mother produces antibodies which are passively transmitted to the baby away the placenta, thus providing protectionAnds birth. Dr De La Fuente: “The mechanism of action of the vaccine and monoclonal antibodies is very similar, since they both target a very specific region: the prefusion-shaped protein of the respiratory syncytial virus (RSV), with a very good immune response in both cases. In pre-marketing studies, the vaccine would also reduce severe symptoms linked to RSV infections (e.g. respiratory failure) and hospitalizations in infants by around 70%. is that it avoids an additional injection for the baby, while ensuring that the baby is protected from birth. For me, this is the main advantage of the vaccine: the baby is already born protected.
As both strategies are based on passive immunization of infants (infants “receive” directly antibodies against RSV), the duration of protection is limited in time, allowing protection for 5-6 months afterAnds birth or afterAnds l’injection. However, this duration of protection makes it possible to protect the infant during the period of high circulation of the virus and during the period of life most vulnerable to RSV infections.
What are the possible disadvantages of vaccination?
In this context, two main disadvantages of vaccination can be highlighted:
• An additional injection for the mother, which can be a source of stress or distress’discomfort;
A busy vaccination schedule. According to Dr. From the Source: “The vaccination schedule for pregnant women is already full. In addition to the RSV vaccine, pregnant women should get vaccinated against whooping coughdue to its active circulation and the risk of serious infection for newborns. They should also get the flu vaccine seasonally, and flu season often coincides with RSV season. Pregnant women may end up with three or more vaccine shots during pregnancy: pertussis, flu, and RSV. Added to this is the Covid-19 vaccine, recommended by the Higher Council for Infectious Diseases, especially for pregnant women with comorbidities increasing their risk of serious COVID-19 infection (gestational diabetes requiring drug treatment, obesity, underlying pulmonary or heart diseases, etc.). Managing this busy vaccination schedule requires careful coordination. Although this is feasible, it requires careful planning on the part of healthcare professionals and expectant mothers.”Dr De La Fuente concluded: “Despite the potential harms of vaccination, vaccination strategies during pregnancy are paramount, as they help reduce mortality and morbidity from infectious diseases, both for the mother and their unborn baby. Vaccination against RSV, in in particular, is essential to protect the newborn during the first 5 to 6 months of his life.”
