Boostrix (3-in-1) vaccine, manufactured by GlaxoSmithKline, was introduced in 2013 for pregnant women to vaccinate against pertussis (whooping cough). Since there is no standalone whooping cough vaccine, Boostrix— which also includes vaccines for diphtheria and tetanus— is used instead. This article provides an overview of the potential risks associated with both the vaccine and the diseases it targets, helping you make an informed decision.
Disease versus Vaccine Risk Summary
| Disease | Risk of getting | Risk of death |
|---|---|---|
| Pertussis | Approx 1 in 30,000 (0.003%) for all ages | Pre vaccine (1952): approx 1 in 16,000 (0.006%) |
| Diphtheria | 2 cases since 1967 | Pre vaccine (1930s): approx 1 in 11,000 (0.009%) for all ages. Last death 1967 |
| Tetanus | No cases in under 5s in over 40 years since 1981 | Pre vaccine (1930s): approx 1 in 137,000 (0.0007%) for all ages |
| Risks from each dose of 3 in 1 vaccine Boostrix (3-in-1) |
|---|
| 1 dose recommended during pregnancy (As per patient information leaflet Feb 2023) |
| Observed side effects post administration of Boostrix (post marketing) |
|---|
|
| Risk Category | Observed Side Effects |
|---|---|
| Up to 1 in 100 (1%) |
|
| Up to 1 in 10 (1% to 10%) |
|
| More than 1 in 10 (10%) |
|

What is pertussis (whooping cough)?
Pertussis, commonly referred to as whooping cough is a highly contagious respiratory disease caused by the Bordetella (B) pertussis bacterium. It can be quite a nasty and prolonged illness. It is rarely serious in children older than six and adults rarely contract the illness even when exposed and have never had it before. The American Journal of Epidemiology in 1949 noted that infants less than 6 months of age had a disproportionately high incidence of severe pertussis, with mortality highest in those under 2 months, before any vaccine is available.
Pertussis begins with cold-like symptoms, including a runny nose, dry cough, fatigue, loss of appetite, and sometimes mild fever. After one to two weeks, it progresses to severe coughing fits with thick mucus, gagging, and vomiting, sometimes accompanied by a “whoop.” Coughing worsens at night, and during the day, the person may seem otherwise fine. Full recovery can take weeks to months, with occasional coughing persisting. Treatment includes rest, hydration, antibiotics and vitamin C in the form of ascorbic acid.
What is the risk of getting whooping cough in Ireland?
Between 2004 and 2017, the risk of getting whooping cough was approximately 1 in 30,000 (0.003%). Not all of these cases were confirmed.
What is the risk of death from whooping cough in Ireland?
There has been four deaths from whooping cough since 1990, three of these were under one year of age. The risk of dying from whooping cough in Ireland in the decade before the vaccine was introduced in 1952 was approximately 1 in 16,000 (0.006%) for all ages.

Does Boostrix (3-in-1) vaccine guarantee protection against whooping cough?
No. You may still get whooping cough even after vaccination and the whooping cough vaccine has a particularly high failure rate. Of the 610 cases of whooping cough between 2013 and 2018, 56% were vaccinated.

In a whooping cough outbreak in LA, all 30 cases were vaccinated [6]

What is diphtheria?
Diphtheria has all but disappeared in countries such as Ireland that have clean water and sanitation. It is a contagious, bacterial disease of the upper respiratory system. It is mainly spread by the coughing and sneezing of infected persons. The first symptoms appear two to five days after infection. They include a sore throat, headache, coughing, fever and swollen lymph nodes in the neck. As the disease progresses, a thick membrane forms on the surface of the tonsils and throat and may extend into the windpipe and lungs. This membrane may interfere with breathing and swallowing. Diphtheria can lead to breathing problems, airway obstruction, paralysis, heart failure, coma and even death if not treated promptly.
What is the risk of getting diphtheria in Ireland?
Since 1967 there have been just two cases of diphtheria in 2015 and 2016.

What is the risk of death from diphtheria in Ireland?
The last death from diphtheria in Ireland was in 1967. The risk of dying from diphtheria in Ireland in the decade before the vaccine was introduced in the 1930s was approximately 1 in 11,000 (0.009%).

Does the Boostrix vaccine guarantee protection from diphtheria?
No – you may still get diphtheria even after vaccination.

What is tetanus?
Tetanus is not a contagious disease. Tetanus is caused by toxins called clostridium tetani that can be present in the gut of many farm animals, in soil, dust and manure. They can enter the body through cuts and puncture wounds but will only multiply in an anaerobic (oxygen-free) environment. It is also called lockjaw because some victims are unable to open their mouths or swallow. Symptoms include severe muscular contractions, headaches and spasms that interfere with breathing.
Careful attention to wound hygiene will eliminate the possibility of tetanus in the majority of cases. Deep puncture wounds and wounds with a lot of dead tissue should be thoroughly cleaned and not allowed to close until healing has occurred beneath the skin. Clean wounds are very unlikely to contain tetanus spores. Human tetanus immunoglobulin injection (not a vaccine) is the recommended treatment where there is a risk of tetanus. Intravenous vitamin C in form of ascorbic acid has also led to more successful outcomes.
What is the risk of getting tetanus in Ireland?
There has been no tetanus cases in under 5s since 1981.
What is the risk of death from tetanus in Ireland?
The last recorded death in CSO statistics from tetanus in an under 5 year old was in 1960. The risk of death from tetanus in Ireland for all ages in the decade before the vaccine was introduced in the 1930s was approximately 1 in 137,000 (0.0007%).


Does the Boostrix (3-in-1) vaccine guarantee protection from tetanus?
No – you may still get tetanus even if vaccinated.
Additonal Vaccine Safety Data
Like all medicines, vaccines come with side effects, sometimes very serious. Parents need to research every vaccine and ensure benefits outweigh the risks.
- See Disease versus Vaccine Risk Summary for list of side effects as per the Boostrix (3-in-1) patient information leaflet
- “Severe allergic reactions can occur to any vaccine but they are very rare and are usually seen in less than 1 in 10,000 people who are vaccinated” [Menitorix PIL, 11/2016]
- As of 11th June, 2024, 246,590 adverse events (including 1,181 SIDS deaths) have been reported on the World Health Organisation Vigiaccess database for 3-in-1 vaccines including Boostrix
- Injury and death from combination vaccines containing pertussis vaccines accounted for 25% of compensation paid from the Vaccine Injury Compensation Program (VICP) in the US since the start of the program in Oct 1988 to 9th Jan 2023. Total compensation paid out over the life of the program to January 2023 is $5 billion.
What are the vaccine ingredients?
| Vaccine | Ingredients as listed on patient information leaflet |
|---|---|
| Boostrix (3-in-1) |
Active substances: Active substances: diphtheria toxoid, tetanus toxoid and pertussis toxoid adsorbed on [popup_anything id=”2213″] hydroxide and [popup_anything id=”2213″] phosphate.
Other ingredients: [popup_anything id=”4326″] and water for injections |