to the editor: Drs. LaHood and Bryant should be commended for outlining the need for vigilant health care screening of the premature infant, especially for emphasizing the importance of influenza vaccinations for close contacts and caregivers, who can serve as reservoirs and agents of disease transmission.

However, two points from the article regarding premature infants and vaccination require explanation. First, administration of acellular pertussis vaccine as part of a tetanus toxoid, reduced diphtheria toxoids, and acellular pertussis vaccine (Tdap; Adacel) is recommended for all close contacts and caregivers of children younger than one year.¹ As with influenza, infected parents can transmit pertussis to their preterm infants. A 2004 study pointed to an adult contact (parent or grandparent) in almost all of the 264 infant cases of pertussis studied.²

In the 1990s, between 29 and 51 percent of infant deaths caused by pertussis were in children younger than 37 and 35 weeks' gestation, respectively.³ Preterm infants also produce lower antibody levels in response to vaccination against pertussis infection.⁴ Providing complete protection and optimizing outpatient care of preterm infants against vaccine-preventable diseases requires administration of Tdap to contacts of preterm infants as part of an overall vaccination regimen.

Secondly, the authors note that the Advisory Committee on Immunization Practices supports rotavirus vaccination of preterm infants after six weeks of age. This recommendation was based on a prelicensure trial of live, oral rotavirus vaccine in 2,070 preterm infants (25 to 36 weeks' gestation; median age 34 weeks).⁵ Rotavirus vaccine has not been studied; thus, its use cannot be recommended in children younger than 25 weeks' gestation. As larger numbers of premature infants survive, the key points discussed here and in the article are important to manage the complex medical needs of this unique patient population.