Due to advancements in medical technology, premature babies today usually survive to adulthood and lead healthy and productive lives. Just a few decades ago, most babies born too early died because their lungs were not ready to breathe on their own. Now there are more children who were born prematurely than ever before. While the vast majority of them do very well, some of them have problems that can persist into late childhood.

Even though premature babies are born early, it is not necessary to postpone routine childhood immunization. In fact, these babies typically have weakened immune systems and need the routine immunization even more than other babies.

The only exception to the immunization schedule for extremely premature babies (babies who are less than four pounds at birth) is that these very tiny babies should not get the hepatitis B vaccine right at birth. The hepatitis B vaccine for these very small babies should be postponed for at least a week. Studies have shown that if the hepatitis B vaccine is given too soon it does not work very well.

Premature Lungs

Babies born more than a month before their due date almost invariably have lungs that are not completely ready to breathe air immediately after birth. Of all the internal organs of a fetus, the lungs are the last to reach maturity. Normally, during the last month of gestation, the fetal lungs produce a substance that allows the lungs to fully expand almost instantly after birth, allowing the newborn baby to start breathing in oxygen right away after birth. Babies who are born early never have the chance to make this substance, so when they are born, doctors must manually pump air and oxygen into their lungs.

Unfortunately, the lungs are not designed to have air actively pumped into them. In the process of keeping these premature babies alive, the active pumping of air into the lungs can sometimes damage the lungs. The longer these babies need aggressive help with their breathing, the more likely their lungs will be damaged.

Consequently, many premature babies, especially the ones who were born extremely early (earlier than twenty-eight weeks gestation), end up with lung damage. These babies with damaged lungs often grow up with weakened lungs, and they tend to develop wheezing later on in life. If these babies catch a cold or flu, they are likely to become extremely ill and often require many days of hospitalization.

RSV

RSV stands for “respiratory syncytial virus.” The word “syncytial” is used to describe this virus because the virus has a tendency to make infected cells stick to each other, as if the cells are having a meeting, or syncytium.

RSV is an extremely common infection among infants. Virtually every child has had this infection by the time she is three years old. Similar to the flu, most RSV infections occur during the winter months. In older children or full-term babies, RSV can cause a bad cold, but it is almost never life threatening. However, in premature babies with damaged lungs, RSV infection could be fatal.

RSV is passed from one person to another by contact of secretion. Most commonly, a tiny amount of secretion from a sick baby containing the virus is touched by a care provider, and the secretion is transferred to other places on the hands. The virus can stay alive on a contaminated surface for many hours. If another person (often other children or babies) touches the contaminated object, the virus is transferred to the next victim.

Since premature babies are more vulnerable to serious RSV infections, doctors routinely recommend very premature babies (usually babies born before thirty-two weeks gestation or more than two months prior to the due date) receive antibody against RSV during each winter season.

The RSV antibody is administered once a month during the entire winter season, when RSV infections are wide spread. Since the RSV antibody injection is very expensive, it is reserved for only extremely premature babies and babies with heart problems. Healthy or full-term babies are not eligible to get the RSV antibody injections.

The Flu Shot

In addition to RSV infections, the flu also poses a big threat to premature babies. For the same reasons that premature babies are more prone to getting serious problems from RSV infections, the flu can make these babies extremely ill. Premature babies with lung damage are significantly more likely to become hospitalized with the flu than healthy babies. For more information on the flu vaccine, please refer to Chapter 18.

It is recommended that premature babies receive flu shots annually, starting at six months of age. During the first flu season, these babies should get a booster flu vaccine to maximize the benefit from the flu vaccine.