Early start to measles vaccine regimen safer for kids
Children's first measles-containing vaccine dose should be given by 15 months of age because of an increased risk of fever and seizures when given later in their second year, according to findings of a retrospective, cohort study published yesterday in JAMA Pediatrics.
The authors, many from Kaiser Permanente, found that the relative risk of fever and seizures 7 to 10 days after administration of measles-containing vaccine, the time when vaccine virus replication is at its peak, was significantly greater among children 16 to 23 months of age at first dose than among those 12 to 15 months old, with the incidence of fever declining steadily from the early to the late part of that spectrum.
In evaluating the effects of different combinations of vaccines, the authors found that the risk of febrile seizures 7 to 10 days after administration of vaccine containing measles, mumps, rubella, and varicella (MMRV) was double than when MMR vaccine was given separately, with or without a separate varicella vaccine injection.
Even when measles-containing vaccine is given later than age 15 months, the risk of febrile seizures is small. Said senior author Nicola Klein, MD, PhD, in a press release from Kaiser Permanente, "Concerned parents should understand that the risk for febrile seizures after any measles-containing vaccine is low—less than one febrile seizure per 1,000 injections."
The researchers used data from the Vaccine Safety Datalink, a collaborative effort of the Centers for Disease Control and Prevention and nine managed care organizations, collected from 2001 to 2011. A total of 840,348 children were included.
Oct 14 JAMA Pediatr abstract
Phase 3 dengue vaccine trial shows good safety, immune response
Three doses of a four-strain dengue candidate vaccine were safe and immunogenic in children in a phase 3 trial whose results were detailed yesterday in Vaccine.
An international team enrolled 250 Malaysian children aged 2 to 11 years in the study of Sanofi Pasteur's CYD-TDV vaccine. The children were randomized 4:1 to receive CYD-TDV or placebo at 0, 6, and 12 months.
Adverse events were similar between the groups after each dose, and serious adverse events were actually higher in the placebo group (11.8% vs 5.5%).
Geometric mean titers (GMTs) of antibodies increased after two vaccine doses for all four dengue virus (DENV) strains in the vaccine compared with baseline, ranging from 4.8-fold for DENV-1 to 8.1-fold for DENV-3. GMTs further increased after the third vaccine dose for DENV-1 and DENV-2, and increases from baseline after three doses ranged from 6.1-fold (DENV-1) to 8.0-fold (DENV-3).
Oct 14 Vaccine study