South Australia plans to offer pregnant women RSV vaccine next year. Here’s what you need to know

Last week, South Australia announced it would offer free respiratory syncytial virus (RSV) vaccinations to pregnant women from next year, the first Australian state or territory to do so.

RSV can be particularly serious for infants, so vaccination during pregnancy is intended to protect the baby.

The vaccine, called Abrysvo, was registered for use in pregnancy by Australia’s Therapeutic Goods Administration in March 2024. It is also approved for use in adults over 60, who are also vulnerable to RSV.

However, RSV vaccination is not funded by the National Immunisation Programme. This means that people who want to be vaccinated must pay for it, unless it is offered by a state or territory programme.

So why is South Australia considering offering this vaccine to pregnant women? And if you’re expecting, is Abrysvo worth considering?

What is VRS?

RSV infects the lungs and airways. It is extremely common, with most children being infected before the age of two. In most people, symptoms are mild, such as a runny nose, dry cough, sore throat, sneezing or headache.

However, in babies under 12 months, and especially under 6 months, symptoms can sometimes be severe, leading to breathing difficulties requiring hospitalization. This is because the infection can spread to the lungs and cause pneumonia.

RSV can also cause serious infection in premature babies and in people with other health problems such as heart disease or weakened immune systems.

There is no specific treatment for this virus once a person is infected. Antibiotics are not effective against RSV infection, so prevention is essential.

Fortunately, there is now a vaccine available in Australia that can protect the most vulnerable. This vaccine is also approved in Europe, the UK and the US

What is the vaccine and how does it work?

The Abrysvo vaccine is a protein subunit vaccine, which means it targets an important protein in the virus called the RSV F protein.

The vaccine given to the mother during pregnancy allows her to produce antibodies against RSV. Antibodies play an important role in our immune system and protect us against infections and serious diseases.

These antibodies cross the placenta to the baby, so that when it is born, it is ready and able to fight off RSV if it encounters the virus.

This vaccine does not contain any live virus, so you cannot get RSV from the vaccine.

The vaccine is recommended for pregnant women between 28 and 36 weeks of pregnancy. Only one dose is needed.

How effective is the vaccine? And is it safe?

In a phase 3 clinical trial, Abryvso was particularly effective in protecting infants during the first three months of life, but its effectiveness declined over time. The trial was conducted in 18 countries and included 3,682 pregnant women who received the vaccine and 3,676 pregnant women who received a placebo injection.

Efficacy (the degree of protection against severe forms of the disease) was 81.8% in the first three months after birth, then dropped to 69.4% at six months. The vaccine was less effective in protecting against moderate infections, with an efficacy of 57.1% up to three months of age.

It is not yet known how long protection lasts beyond the first six months of life. However, babies are most at risk during these first months of life.

The rate of reported side effects was similar for women who received the vaccine (13.8% reported an adverse event within 1 month of vaccination) and women who received the placebo (13.1% reported an adverse event).

The most commonly reported local reaction in both the vaccine and placebo groups was pain at the injection site. The most commonly reported systemic symptom in both groups was fatigue.

The rate of preterm births was similar in both groups. There were 28 cases of preterm births in the vaccinated group, compared with 23 cases in the unvaccinated group.

Are there any other alternatives?

Beyfortus (also known as nirsevimab) is a treatment called a long-acting monoclonal antibody. It can be given to babies from birth. Just like the antibodies that cross the placenta after the mother is vaccinated during pregnancy, nirsevimab can also protect the baby for the first six months of life.

However, access to nirsevimab currently varies depending on the state you live in. Western Australia, Queensland and New South Wales have funded their own programs this year. It is not yet known which states, if any, will fund nirsevimab in 2025.

How to access this vaccine?

In Australia, Abryvso is not currently funded by the National Immunisation Program, but can be purchased privately with a prescription from your doctor.

Last week, South Australia announced Australia’s first publicly funded program, which will begin in 2025. The South Australian government will use a combination approach to prevent RSV disease in newborns. The state will fund Abryvso for pregnant women. For babies with health conditions, babies born prematurely or babies whose mothers have not been vaccinated, the monoclonal antibody will be recommended.

Now that an effective and safe vaccine is available, all pregnant women should discuss this vaccine with their GP or maternity care provider and consider receiving it to protect their newborn against RSV.