What timing of vaccination is potentially dangerous for children younger than 2 years?

Figures & data

Table 1. French 2015 vaccination schedule and recommendations for children younger than 2 years of age.

Vaccines	2 months	4 months	11 months	12 months	16–18 months
DTaP-IPV-Hib	X	X	X
HBV	X	X	X
PCV	X	X	X
MenC				X
MMR				X	X

DTaP-IPV-Hib: diphtheria tetanus acellular pertussis-inactivated polio vaccine-Hi b vaccine, PCV: pneumococcal conjugate vaccine, MenC: meningococcal C conjugate vaccine, MMR: measles-mumps-rubella vaccine, HBV: hepatitis B vaccine.

Table 2. Potentially damaging vaccination delay for each dose of each recommended vaccine for children younger than 2 y according to the French immunization schedule: Round 1.

		Vaccination delay
Vaccines	Recommended age^*	%	95% CI	%	95% CI	%	95% CI	%	95% CI	%	95% CI
DTaP-IPV/Hib^a		≥ 1 d		7 d		15 d		28 d		Other/NA^f
1^stdose	2 months	24.1	11.0–43.9	13.8	4.5–32.6	27.6	13.4–47.5	31.0	16.0–51.0	3.5	0.2–19.6
2^nd dose	4 months	6.9	1.2–24.2	3.5	0.8–17.8	24.1	11.0–43.9	58.6	39.1–75.9	6.9	1.2–24.2
1^st booster dose	11 months	≥ 2 m		≥ 6 m		≥ 1 y		≥ 2 y		Other/NA^f
		48.3	29.9–67.1	34.5	18.6–54.3	3.5	0.1–14.4	3.5	0.1–14.4	10.3	2.7–28.5
PCV^b		≥ 1 d		≥ 15 d		≥ 1 m		≥ 2 m		Other/NA^f
1^st dose	2 months	31.0	16.0–51.0	37.9	21.0–50.7	24.1	11.0–43.9	6.9	1.2–24.2	0.0	0.0–10.7
2^nd dose	4 months	20.7	8.7–40.3	31.0	16.0–51.0	34.5	18.6–54.3	10.3	2.7–28.5	3.5	0.2–19.6
booster dose	11 months	3.5	0.2–19.6	20.7	8.7–40.3	41.4	26.7–57.8	15.0	6.8–37.6 )	17.2	6.5–36.5
MMR^c		≥1 m		≥ 3 m		≥ 6 m		≥ 1 y		Other/NA^f
1^st dose	12 months	75.9	56.1–89.0	20.7	8.7–40.3	0.0	0.0–10.7	0.0	0.0–14.6	3.5	0.2–19.6
2^nd dose	16–18 months	24.1	11.0–43.9	24.1	11.0–43.9	31.0	16.0–51.0	13.8	4.5–32.6	6.9	1.2–24.2
MenC^d	12 months	≥1 m		≥ 2 m		≥ 6 m		≥ 1 y		Other/NA^f
		51.7	32.9–70.1	13.8	4.5–32.6	17.2	6.5–36.5	17.2	6.5–36.5	0.0	0.0–14.6
HBV^e	11 months	≥ 16 m		≥ 6 y		≥ 11 y		≥ 16 y		Other/NA^f
		41.4	24.1–60.9	13.8	4.6–27.0	31.0	16.6–45.7	6.9	1.2–24.2	6.9	1.2–24.2

^a diphtheria tetanus acellular pertussis-inactivated polio vaccine-Haemophilus influenzae b vaccine;

^b pneumococcal conjugate vaccine;

^c Measles-Mumps-Rubella vaccine;

^d meningococcal C vaccine;

^e hepatitis B vaccine ;

^f not answered. Percentage of vote by experts were rounded off to one decimal, with 95% confidence interval (95% CI)

* 2013 vaccination schedule and recommendations,⁹ still ongoing in 2016

Figure 1. Development of experts' choices from round 1 to round 3 for each recommended injection of routine vaccines for children younger than 2 y.

Table 3. Potentially damaging vaccination delays for each dose of each vaccine in children younger than 2 y according to the French immunization schedule.

		Most frequently cited delay if consensus (> 70%)			2^nd most frequently cited delay in the absence of consensus
Vaccines		Delay 1	%	95% CI	Delay 2	%	95% CI	Potentially dangerous delay
DTaP-IPV/Hib^a	1^stdose	15 d	71.4	51.1–86.0	/			15 d
2^nd dose		15 d	78.6	58.5–91.0	/			15 d
1^st booster dose		1 month	52.5	36.3–68.2	2 months	42.9	25.0–62.6	2 months
PCV^b	1^st dose	15 d	60.7	40.7–77.9	7 d	32.1	16.6–52.4	15 d
2^nd dose		15 d	85.7	66.4–95.3	/			15 d
booster dose		1 month	67.9	47.6–83.4	2 months	28.6	14.0–48.9	2 months
MMR^c	1^st dose	1 month	89.3	70.6–87.2	/			1 month
2^nd dose		6 months	64.3	44.1–80.7	1 month	22.5	11.4–38.9	6 months
MenC^d		1 month	82.8	63.5–93.5	/			1 month
HBV^e		11 y	78.6	58.5–91.0	/			11 y

^a diphtheria tetanus acellular pertussis-inactivated polio vaccine-Haemophilus influenzae b vaccine;

^b pneumococcal conjugate vaccine;

^c Measles-Mumps-Rubella vaccine;

^d meningococcal C vaccine;

^e hepatitis B vaccine;

Percentages of vote by experts were rounded off to one decimal, with 95% confidence interval (95% CI)