Pneumococcal conjugate vaccines 7-valent and 13-valent (PCV7/PCV13) in children younger than 5 years of age in Israel were less prominent in meningitis than in nonmeningitis invasive pneumococcal disease (nm-IPD), according to S. Ben-Shimol, MD, and associates.

Between July 2000 and June 2015, 4,168 IPD episodes were reported; 426 (10.2%) were meningitis. The PCV13 serotype (13VT) meningitis rates significantly declined by 93% (incidence rate ratio = 0.07), from 3.6 ± 1.3 in the pre-PCV period to 0.3 in the last year of the study. Also, the 13VT nm-IPD rates significantly declined by 95% (IRR = 0.05), from a rate of 40.0 ± 5.4 in the pre-PCV period to 1.9. The non-13VT meningitis rates significantly increased by 273% (IRR = 3.73), from 0.8 ± 0.3 in the pre-PCV period to 3.0. And the non-13VT nm-IPD rates also significantly increased by 162% (IRR = 2.62), from 4.5 ± 0.8 in the pre-PCV period to 11.8.

The researchers noted that the increase in non-13VT meningitis was partially driven by a sharp and significant increase of serotype 12F, along with the other predominant non-13VT serotypes that caused meningitis: 15B/C, 24F, and 27. The serotypes also were predominant in non-13VT nm-IPD, as were additional serotypes 8, 10A, 33F, 7B and 10B.

“This finding may be attributed to the younger age of children with meningitis and differences in causative serotypes between the two groups, as the decline of the incidence of meningitis and nm-IPD caused by vaccine-serotypes is similar,” researchers concluded. “Continuous monitoring of meningitis and nm-IPD is warranted.”

Find the full study in Vaccine ( doi: 10.1016/j.vaccine.2016.07.038 ).