Is The Whooping Cough Vaccine Safe?

Overview

Yes, the whooping cough - also called pertussis - vaccine is very safe, for all people older than two months of age. In the past, concerns were raised about the vaccine safety at the National Childhood Encephalopathy Study with the fear that the whole-cell pertussis vaccine was associated with the onset of neurological problems and brain damage in young children.

After careful analysis, there was no sufficient evidence to corroborate the association between the whole-cell pertussis vaccine and neurological problems or brain damage in young children. ^1,2,3 Additionally, nowadays the two most used vaccines against pertussis are “acellular” vaccines, which are a different type of vaccine compared to the whole-cell pertussis vaccines. The vaccines currently used, the acellular vaccines, are much more modern, safer, and have fewer side effects than the older vaccines (the whole-cell vaccines). ^2,3

It is not only safe for all people older than two months of age to be vaccinated against pertussis but it is also recommended by the World Health Organization. Just as with any other vaccine, side effects can occur after pertussis vaccine administration. However, in most cases those are mild - including low fever and fatigue - and tend to get better on their own. Severe side effects are rare and do not outweigh the great health benefits that come with vaccination against pertussis. ^1,2,3

About Whooping Cough 

Whooping cough, also called pertussis, is a highly contagious respiratory disease that occurs only in humans caused by a bacteria named Bordetella pertussis. It spreads from person to person through coughing, sneezing, sharing the same space, or breathing the same air for a long time with people that are infected. ^1,2,3

The symptoms normally start five to ten days after exposure, but it can also take up to three weeks. The most contagious phase is around two weeks after the symptoms start. The first symptoms occur for one to two weeks and are similar to a common cold, including a runny nose, low fever, cough, and, for babies, a pause in breathing (also called apnea). After that, more severe symptoms can occur, such as violent and rapid coughing, which can be followed or accompanied by vomiting and exhaustion, or in the case of young children, even turning blue. ^1,2,3

Even though whooping cough can cause serious illness at any age, it is more dangerous for babies, especially if they did not get all the recommended vaccines against the disease or if the mother did not get vaccinated during pregnancy. Almost 50% of babies less than one year of age need to be hospitalized when they have the disease, 25% develop pneumonia (an infection of the lungs) and 60% get pauses in breathing (apnea).^1,2,3

Pertussis vaccination is the single best measure to protect people of all ages against whooping cough and to control the disease. That makes immunization practices against pertussis a public health matter, which is why the pertussis vaccine is widely included in many National Immunization Programs around the world. ^1,2,3

Is the Whooping Cough vaccine safe?

Yes, the whooping cough vaccine is very safe, including for pregnant women and babies older than two months of age. It does not increase the risk of pregnancy complications. It is also important to know that you can not get whooping cough from the vaccine. ^1,2,3

How does the whooping cough vaccine work?

The whooping cough vaccine is a type of “acellular” vaccine. This is a modern type of vaccine that causes fewer side effects than older vaccines and is very safe. ^1,2

The vaccine contains a really small amount of proteins of the Bordetella pertussis bacteria, the one that causes the whooping cough disease. Our immune system acts against these “small pieces” of the bacteria by producing antibodies against them. In this way, our immune system “gets ready” to fight the disease if you are ever exposed to the bacteria itself, preventing you from getting severe symptoms if infected. ^2,3

Because the vaccine contains just small amounts of proteins of the bacteria and not the bacteria as a whole, it is important to emphasize that the vaccine can not cause the disease. ^2,3

How long are you protected for?

The protection given by pertussis vaccination lasts from 4 up to 20 years. That is why it is recommended to all adults to get a shot every 10 years. ^2,3

The highest levels of protection are in the first two years after vaccination, with protection getting lower in the years after that. Therefore, even a fully vaccinated person can get the disease, but in these cases usually, the symptoms are not severe and do not require hospitalization. ^2,3

Side Effects of the whooping cough vaccine

The vast majority of people who get pertussis vaccines do not get any severe effects. Nevertheless, just as with any other vaccine, side effects can happen after pertussis vaccination. Fortunately, when side effects occur, they are usually mild and get better in a few days without needing any treatment. The most common side effects include: ^1,2,3

• Soreness, redness, pain, and/or swelling where the vaccine was applied (most common side effect);
• Fatigue;
• Fever;
• Loss of appetite;
• Vomiting.

Severe side effects can also occur, such as seizures and severe allergic reactions, but those are rare and do not outweigh the benefits of the vaccine.

Getting the whooping cough vaccine

The two most used vaccines against whooping cough around the world are DTaP and Tdap, which also protect against tetanus and diphtheria. Some vaccines have proteins against polio and hepatitis B as well. The vaccination is recommended for everyone older than 2 months of age. ^1,2,3 Check with your general practitioner if you should get vaccinated. If you also need to get a flu vaccine, you can get it at the same time as the pertussis vaccine without any problems. ^1,2,3

How you receive the vaccine

The vaccine is given via intramuscular, meaning it is applied through an injection in the muscles, usually in the upper arm for adults.

The number and type of shots that are given depend on the age and according to the World Health Organization, are as follows:

• Five shots of DTaP for children younger than 7 years of age at the following ages:  2, 4, 6, 15-48 months, and 4-6 years;
• Tdap for adolescents: one shot at 11-12 years;
• Tdap for pregnant women:  at the 27-36^th week of every pregnancy, the earlier in this interval the better;
• Tdap for adults: every 10 years for those who were already vaccinated or anytime for those who were never vaccinated.

When should you get the vaccine

• Babies should get five shots of the vaccine at the ages of 2, 4, 6, 15-48 months, and 4-6 years;
• Adolescents should get one shot of the vaccine between the ages of 11 and 12 years;
• Pregnant women should get one shot of the vaccine in every pregnancy, between 27 and 36^th week of pregnancy, the sooner at this interval the better;
• Adults who were vaccinated previously should get one shot of the vaccine every 10 years and adults who were never vaccinated should get one shot of the vaccine as soon as possible. ^1,2,3

Whooping cough vaccine and pregnancy 

The pertussis vaccine is only safe for babies after 2 months of age. However, pertussis can cause serious illness and even death for babies younger than 2 months of age. Therefore, the best way to protect young babies is by vaccinating pregnant women. By vaccinating expectant mothers in the third trimester of pregnancy, women pass their antibodies to their babies before birth and while breastfeeding, protecting them against the disease in the first months of life, while it is still not safe for them to be vaccinated. ⁴

Expectant mothers should get vaccinated against pertussis between the 27th and 36th of pregnancy. The peak of antibodies occurs two weeks after vaccination and takes a while for the antibodies to pass to the baby. Therefore, the vaccination should preferably happen at the beginning of the 27-36^th-week interval. Vaccination during pregnancy decreases the risk of the disease in babies younger than two months by almost 80%. ⁴

Importantly, if the woman has two pregnancies that are less than a year apart, she should still get vaccinated in each pregnancy, since the number of antibodies gets lower over time after vaccination. ^4,5

If by any chance a woman, unfortunately, was not vaccinated during pregnancy, she should still get vaccinated after giving birth. In this way, it is less likely that the woman can pass the disease to the baby if she gets infected. However, the baby will still be vulnerable to catching the disease from others. ^4,5

When it comes to visits to newborns, it is important to know that adults might not know that they are infected and pass the bacteria to the baby. In fact, when a baby gets whooping cough, it is usually transmitted by someone in their household, such as parents, siblings, grandparents, and caregivers. Therefore, it is recommended that everyone that visits a newborn baby is properly vaccinated against pertussis. If an adult is not up to date with his pertussis vaccination, it is important to get a shot at least 2 weeks before visiting a baby. ^4,5

Summary

Whooping cough or pertussis is a very contagious respiratory disease that can cause severe illness and death, particularly in young children. Usually, the disease starts as a common cold and can evolve to more severe symptoms, like violent and rapid coughing, and even evolve to death. 

The best way to protect people against the disease is through vaccination and currently, the most used vaccines worldwide are DTaP and Tdap. These are a modern type of vaccines – called acellular vaccines – which are highly safe and produce few side effects. When side effects occur, those are usually mild and get better on their own. These vaccines contain tiny parts of the bacteria that causes the whooping cough disease. Our immune system acts against these tiny parts, producing antibodies and protecting us against the disease. As the vaccine does not contain the bacteria as a whole, the vaccine cannot cause the disease.

The vaccine is recommended for everyone older than 2 months of age, including one shot for pregnant women in every pregnancy in the third trimester. Because the amount of antibodies decreases over time, all adults should get a booster shot every 10 years.

It is not safe to vaccinate children younger than 2 months of age against pertussis, which is the age that the disease is more severe. That is why it is extremely important to vaccinate expectant mothers, so they can pass their antibodies to their babies. It is also important for adults visiting newborns to be vaccinated since they can be infected without showing any symptoms and inadvertently pass the bacteria to the baby.