Your Child's First 6 Months of Vaccines

Childhood vaccines like DTaP protect against multiple diseases with minimal risks

/ Author:  / Reviewed by: Joseph V. Madia, MD

Keeping a child up to date on vaccines often seems like a lot of doctor visits and shots to a new parent. It’s helpful to know what all those shots are for, as well as their risks and benefits.

Getting a host of different diseases throughout childhood was once a rite of passage for kids. The problem was that many of those children didn't survive the diseases, or they suffered lifelong disability from them.

The World Health Organization (WHO) estimates that two to three million deaths a year are prevented due to vaccination programs across the world.

Now that those diseases are seen less often, many parents are not sure what each immunization is for. They may wonder about the severity of the disease that the vaccine protects against and what the risks of the vaccine are.

"The vaccines given in the first 6 months are the most deadly to a child that age," said Thomas Seman, MD, a pediatrician at North Shore Pediatrics in Danvers, Mass. and a dailyRx expert.

Below is a description of each shot, the diseases it protects against and the most common possible side effects of the vaccine in the Centers for Disease Control and Prevention childhood immunization schedule from birth through 6 months old.

One vaccine reaction that is possible with some vaccines but extremely rare is an allergic reaction. Severe allergic reactions from the hepatitis B vaccine can occur in about 1 in 1.1 million doses. The DTaP shot can also cause a severe allergic reaction in less than 1 in 1 million doses.

Hepatitis B

The Hepatitis B vaccine is given shortly after a baby is born to protect against this liver disease. Hepatitis B is typically passed along through blood or sexual contact, but the vaccine is given at birth because a mother with hepatitis B could infect her baby. Or the baby could contract Hepatitis B through other sources in the hospital or even in a later childcare setting.

Hepatitis B can be a lifelong disease. In addition to symptoms like pain, nausea and vomiting, hepatitis B can cause a person to develop cirrhosis of the liver or liver cancer.

The most common side effects of the vaccine are soreness where the shot was given and an elevated temperature.


Rotavirus  is the leading cause of severe diarrhea and vomiting in children across the world. It can lead to dehydration and kills half a million children every year.

The most common side effects are irritability and possibly mild, temporary diarrhea or vomiting. One rare side effect that can occur in 1 in 100,000 babies is a blockage in the bowels called intussusception, which requires medical attention.


The DTaP shot protects against three diseases: diphtheria, tetanus and pertussis, also known as whooping cough.

Diphtheria causes a thick covering in the back of the throat and is now almost nonexistent in the US because of the vaccine. It can cause breathing difficulties, paralysis, heart failure and death.

Tetanus, also called lockjaw, causes painful tightening of the muscles all over a person's body, including locking the jaw so they cannot open their mouth or swallow. About one in ten people who get tetanus die from it.

Pertussis, or whooping cough, is a severe respiratory tract infection in which a person has violent coughing that can last weeks or even months. Although most children and adults do not suffer complications from pertussis, babies who catch it can develop pneumonia, have slowed breathing, damage a lung or even die.

Dr. Seman noted that pertussis can actually slow down a child's breathing to the point of suffocation, and after resuscitation, the child could have brain damage.

"Pertussis is on the rise in some parts of the US, and the largest repository for the disease is the 11 to 21 year olds," Dr. Seman said. "Unfortunately this is also the same age group that does most of the babysitting and camps and have the greatest interactions with different families as they each visit school friends."

The most common side effects of the DTaP are fever, fussiness, tiredness and redness, swelling or soreness where the shot was given. Vomiting is a less common side effect.

Rare but possible side effects include a very high fever, non-stop crying for three hours or more and a seizure, though the seizures (in 1 out of 14,000 children) do not cause lasting damage.


The Hib vaccine protects against Haemophilus influenzae type b, a bacteria that can cause pneumonia, a severe throat infection, meningitis or other infections. Meningitis is an infection of the spinal cord and brain.

An infection from Hib can cause brain damage, hearing loss, loss of limbs or even death. The only reported side effects of the Hib vaccine are redness, warmth or swelling where the shot was given or a fever over 101 degrees.

"HiB used to be the leading cause of meningitis leading to death, deafness, blindness in younger children," said Dr. Seman. "Since the effectiveness of the vaccine has been good, this is not seen that often, so pneumoccocal disease became the leading cause of meningitis, deafness, blindness and death."

PCV (pneumonia)

The PCV vaccine is the pneumococcal conjugate vaccine that protects against several different strains of pneumonia. Pneumonia is an infection of the lungs that can cause coughing, fever, fatigue, nausea, vomiting, rapid breathing, shortness of breath, chills or chest pain. It is possible to die from pneumonia.

The most common side effects of the PCV vaccine are drowsiness, loss of appetite, fever, irritability and redness, swelling or tenderness at the injection site.

IPV (polio)

The IPV vaccine stands for inactivated polio vaccine and protects against polio. Polio is transmitted through the throat and intestinal tract and can cause paralysis, permanent disability or death. The disease was very common in the US until the first polio vaccine in 1955.

The previous polio vaccine was a "live virus" vaccine, but the currently given vaccine contains a deactivated virus. The only reported side effect is soreness or redness at the injection site.

After 6 Months

These vaccines are the only ones given up until a child is 6 months old. Babies aged 6 months and older can also get the flu vaccine during flu season.

It seems as though babies get a lot of shots during those first six months, but the injections protect them against eight different diseases, all of which can be deadly. The extra shots at the 4-month and 6-month visits are to boost the child's immunity.

Once a child turns 1 year old, it is recommended that they get several additional vaccines, which include the measles, mumps, and rubella vaccine, the varicella (chickenpox) vaccine and the hepatitis A vaccine.

We May Not See Them – But The Diseases Are Still There

Several of these diseases are rarer now because of the widespread use of vaccines to prevent them. But, that does not mean they are gone.

"Even though we have seen a great reduction in these diseases, the germs are still all around us, mostly in everyone's mouth and nose since these organisms are common oral and nasal flora," Dr. Seman said.

"So, everyone has the possibility of harboring these germs in their mouths," he said. "When they kiss or interact with an infant, they can potentially infect the child with these significant pathogens."

Dr. Seman pointed out, for example, that polio is still present in the Northern hemisphere, especially in several smaller Caribbean islands where tourists may visit.

"We always feel quite in control on our street and in our hometown, but all of the diseases are only a few hours plane ride away," Dr. Seman said. "Either we visit or others come from these areas and expose us and our family."

It is also not always possible to treat these diseases, he said. Some can be treated with antibiotics while others cannot be treated and must run their course.

"There are side effects to everything we do, but let us take charge of our children's health and the future and immunize to protect them from many of these diseases," Dr. Seman said. "This is a clear example of the old saying, 'An ounce of prevention is worth a pound of cure.'"

Review Date: 
April 22, 2013