Whooping babies

By Dr Zulkifli Ismail, TheStar 20/01/2008

The good news is, the incidence of whooping cough (pertussis) among newborns is very low. The bad news is, those who do contract it are getting it from infected adults. Here’s how you can protect your children.

It had been ten years since she gave birth to her son Zaki, and today, Sabariah is the proud mother of her new baby girl Zara. The weeks after bringing Zara home from the hospital were hectic: relatives and friends were popping in to visit the new baby every day. Sabariah and hubby Amir ran themselves ragged, entertaining the steady stream of well-wishers. One day, Sabariah started coughing and developed flu-like symptoms, with a tingling sensation in her throat. Blaming it on the stresses of being a new mother, she decided to treat herself with over-the-counter cough medications.

The majority of pertussis infections in newborns are actually caused by infected adults. - Reuters photo

Within a week, Sabariah’s cough became persistent and she became more breathless. She finally went to see her doctor and was diagnosed with pertussis, also known as whooping cough. At that point, baby Zara was starting to experience symptoms of the infection – she had bouts of severe coughing ending with a “whoop”, and each cough made her face red and left her more irritable and distressed. Zara too was diagnosed with pertussis.

Sabariah was told that her immunity had decreased over the years even though she had been vaccinated against pertussis as a baby. In the meantime, Zara had yet to complete her three-dose vaccination course against pertussis, which made her vulnerable to the disease. To prevent the infection from spreading, the doctor recommended an immediate booster vaccination for 10-year-old Zaki.

What is pertussis?

Pertussis is a serious infection of the respiratory system caused by the Bordetella pertussis bacteria. Even though this disease is preventable with vaccination, there is still between 30 and 50 million cases of pertussis infections worldwide annually, with 300,000 of these cases resulting in deaths.

In Malaysia, all babies are required to receive the DTP (Diphtheria, Tetanus and Pertussis) vaccine. The effectiveness of the vaccine has led to a dramatic decline in pertussis infections. In fact, the World Health Organization’s Immunization Profile of Malaysia reports that only six cases of pertussis were reported in 2006.

Infants receive their DTP vaccination shots at the age of two months, three months and five months, with a booster at 18 months. - Reuters photo

Full immunity against pertussis for newborns is only attained after the third dose of the vaccine, administered when the baby is five months old. Exposure to the bacteria at any time before full immunity is achieved can lead to an infection, which can result in deadly effects. The problem is, immunity doesn’t last forever; it decreases by the time a child turns 11 or 12 years old.

However, 12-year-olds are given a booster shot against pertussis, so it’s unlikely that they will contract pertussis and pass it on to a newborn baby. The majority of pertussis infections in newborns are actually caused by infected adults.

What are the symptoms?

Early symptoms of a pertussis infection mimic those of the common cold. These would include a runny nose, mild coughing, low fever and sneezing. Between one and two weeks into the infection, coughing intensifies into coughing spells. Most of the time, a whooping sound accompanies the coughing at the end of the bout, hence its name. Persistent coughing spells may also cause some children to vomit.

However, not everyone infected with pertussis will produce a whooping sound or a coughing spell. Babies may gasp for breath, subsequently turning red in the face. They may even stop breathing for several seconds during bad spells (“apnoea”). Some adults or adolescents may just develop prolonged coughs, without the whooping sound. These often go undiagnosed and are treated as conditions like the common cold or asthma.

How contagious is it?

A pertussis infection is highly contagious as it is spread through droplets in the air when an infected person sneezes, coughs or laughs. Thus, anyone located in the same room as an infected person risks catching the infection simply by inhaling, or by rubbing their noses and mouths with their hands after unknowingly touching the droplets. Also, an infected person can start spreading the bacteria from the early stages of infection, until about two weeks after coughing commences.

Can pertussis be treated?

While infected adults, adolescents and older children recover from pertussis with a course of antibiotic treatment, younger children and babies may need to be hospitalised. Complications that may arise include pneumonia, dehydration, ear infections and seizures. Serious complications of pertussis that can cause death in babies younger than six months of age include cerebral haemorrhage, hypoxia and encephalopathy (infection of the brain).

Can pertussis be prevented?

Fortunately, in preventing pertussis infections, modern science has brought us the pertussis vaccine. It is administered as a three-in-one vaccine known as DTP, a vaccination against Diphtheria, Tetanus and Pertussis. The DTP vaccination is one of the vaccines under the National Immunisation Programme of the Ministry of Health of Malaysia, which aims to immunise every child in Malaysia.

Infants receive their DTP vaccination shots at the age of two months, three months and five months, with a booster at 18 months. As the effectiveness of pertussis vaccinations typically last about five years, it is recommended for adults to be given boosters to prevent pertussis. This is especially important so that adults don’t act as reservoir of infection and pass it on to a baby who has yet to complete his or her full course of DTP vaccination.

The adult booster vaccine differs from the infant vaccine and has less diphtheria and pertussis components (dTp). Adult booster vaccines are encouraged for all adults who are in contact with infants. These include nursery teachers, day-care workers, maids and nannies, even health care workers especially paediatric hospital staff.

Lifelong immunity

If you are a parent, ensure that your baby is given the appropriate vaccinations against pertussis according to the local immunisation schedule. Ensure continued immunity against this infection for your children by making sure that they receive their booster shots at 12 years old. Adults are also strongly recommended to get booster shots every 10 years as well. Bring this up at your next visit to the doctor.

Ø Dr Zulkifli Ismail is a consultant paediatrician, immediate-past president of the Malaysian Paediatric Association and chairman of the Positive Parenting Management Committee. The Positive Parenting Programme is managed by Malaysian Paediatric Association and supported by an unconditional educational grant from GlaxoSmithKline. For more information, please visit www.mypositiveparenting.org