乌鸦传媒

There were no new or unexpected adverse events, and serious adverse events were rare, following the introduction of diphtheria-tetanus-acellular pertussis (DTaP) vaccines, researchers found.

In a review of a spontaneous surveillance reporting system, about a quarter of patients had injection site erythema, almost 20% had pyrexia and 15% had injection site swelling, reported Pedro L. Moro, MD, of the CDC in Atlanta, and colleagues.

In addition, about 11% of adverse events were serious adverse events, they wrote in .

They noted that postmarketing observational studies for DTaP-containing vaccines have "a good safety record," but that the initial studies for the DTaP vaccines conducted by the (VAERS) did not include any of the current DTaP vaccines available, and it only covered a short time period.

Researchers examined data from VAERS from 1991 to reports received by March 17, 2017. Overall, there were just over 50,000 reports that involved receipt of either Infanrix, Pediarix, Kinrix, or Daptacel or Pentacel. The earliest current licensed DTaP vaccines are Infanrix (approved in 1997), and Daptacel (approved in 2002), the authors noted.

About 11% of adverse events were coded as serious; 1.7% reported death. There were 844 deaths reported in total to VAERS, with death certificates and autopsy reports available for 725. Examining causes of death, 48.3% were due to sudden infant death syndrome (SIDS). Of these SIDS cases, 62% occurred in boys and over 90% were age <6 months.

There were 163 reports of anaphylaxis, with median patient age of 4. Of these, symptom onset time could be determined in 103 cases, and about three-quarters of those occurred within 30 minutes post-vaccination. The authors noted that almost 95% of the DTaP vaccines were given at the same time as other routine vaccines, as recommended by the .

Moro's group also noted the presence of "vaccination errors" (such as incorrect vaccine or vaccine formulation or administration of the vaccine at the wrong site) in their analysis, and called for "measures to prevent their occurrence."

In an , Flor M. Munoz, MD, of Baylor College of Medicine in Houston, noted that after acellular vaccines were introduced, there was a resurgence in pertussis in the U.S., and that the DTaP vaccine has been associated with "a shorter duration of protection," which requires booster doses in adolescents, adults and pregnant women.

Munoz spoke to the "imperative need" to develop more immunogenic vaccines against pertussis, and spoke to progress being made in the research field.

"Active research is ongoing for the development of novel vaccines, including live attenuated vaccines, whole-cell vaccines with reduced endotoxin content to be less reactogenic, outer membrane vesicles-based vaccines, and acellular vaccine formulations prepared with new adjuvants or additional and novel antigens [as detailed in ]" she wrote.