dTap vaccine is a combination vaccine that helps protect against three serious diseases: diphtheria, tetanus, and pertussis (whooping cough). This vaccine is given as a booster to help strengthen the body’s defense system, or immunity, against these diseases. In this clinical trial, health care workers receive the dTap vaccine to see how their immune systems respond to it, both before and four weeks after getting the booster shot. The goal is to understand how well the vaccine works in boosting immunity against these diseases in people who work in health care settings.

Diphtheria – Diphtheria is a bacterial infection caused by Corynebacterium diphtheriae. It primarily affects the mucous membranes of the throat and nose. The disease begins with a sore throat, fever, and chills. As it progresses, a thick, gray membrane forms in the throat, which can lead to difficulty breathing and swallowing. The bacteria produce a toxin that can spread through the bloodstream, potentially affecting the heart and nerves. Without intervention, the infection can cause severe complications.

Tetanus – Tetanus is a serious bacterial infection caused by Clostridium tetani. The bacteria produce a toxin that affects the nervous system, leading to muscle stiffness and spasms. The disease often starts with muscle stiffness in the jaw, commonly known as lockjaw. As it progresses, the stiffness spreads to other muscles, causing severe muscle spasms and difficulty swallowing. The spasms can be strong enough to cause bone fractures. The bacteria typically enter the body through wounds or cuts.

Pertussis (Whooping Cough) – Pertussis, also known as whooping cough, is a highly contagious respiratory disease caused by the bacterium Bordetella pertussis. It starts with symptoms similar to a common cold, such as a runny nose, mild cough, and fever. As the disease progresses, severe coughing fits develop, which can be followed by a high-pitched “whoop” sound when breathing in. The coughing fits can lead to vomiting and exhaustion. The disease is particularly dangerous for infants and can lead to complications such as pneumonia. The bacteria spread through respiratory droplets from coughing or sneezing.