Vaccination

Percentage of children age 12-23 months and children age 24-35 months who received specific vaccines at any time before the survey according to vaccination card, according to mother’s report, according to either vaccination card or mother’s report, and percentage who received specific vaccines by appropriate age

Definition

1)      Percentage of children age 12-23 months who received specific vaccines at any time before the survey according to vaccination card.

2)      Percentage of children age 12-23 months who received specific vaccines at any time before the survey according to mother’s report.

3)      Percentage of children age 12-23 months who received specific vaccines at any time before the survey according to either vaccination card or mother’s report.

4)      Percentage of children age 12-23 months who received specific vaccines by appropriate age.

5)      Percentage of children age 24-35 months who received specific vaccines at any time before the survey according to vaccination card.

6)      Percentage of children age 24-35 months who received specific vaccines at any time before the survey according to mother’s report.

7)      Percentage of children age 24-35 months who received specific vaccines at any time before the survey according to either vaccination card or mother’s report.

8)      Percentage of children age 24-35 months who received specific vaccines by appropriate age.

Coverage:

Population base: Living children age 12–23 months and 24-35 months (KR file)

Time period: 3 years preceding the survey

Numerators:

1)      Number of living children age 12–23 months and 24-35 months receiving specified vaccines, fully vaccinated (basic antigens), fully vaccinated (according to national schedule), all age appropriate vaccinations, and no specified vaccines, according to information on vaccination card (b5 = 1 & h1 = 1 & vaccination given [see Calculation])

2)      Number of living children age 12–23 months and 24-35 months receiving specified vaccines, fully vaccinated (basic antigens), fully vaccinated (according to national schedule), all age appropriate vaccinations, and no specified vaccines, according to mother’s report (b5 = 1 & h1 ≠ 1)

3)      Number of living children age 12–23 months and 24-35 months receiving specified vaccines, fully vaccinated (basic antigens), fully vaccinated (according to national schedule), all age appropriate vaccinations, and no specified vaccines, according to information on vaccination card or mother’s report (b5 = 1 & vaccination given [see Calculation])

4)      Number of living children age 12–23 months and 24-35 months receiving specified vaccines, fully vaccinated (basic antigens), fully vaccinated (according to national schedule), all age appropriate vaccinations, by the appropriate age (b5 = 1 & vaccination given by appropriate age [see Calculation])

Denominators:

a)       Number of living children age 12–23 months (b5 = 1 & b19 in 12:23)

b)      Number of living children age 24-35 months (b5 = 1 & b19 in 24:35)

Variables: KR file.

For the above, hxxd, hxxm, and hxxy are the day, month, and year the child received the vaccination.

Calculation

Numerators:

Number of living children between age 12 and 23 months or between age 24 and 35 months at the time of the survey who received the specified vaccine.

Specific vaccines:

The following provides a list of the typical vaccines reported, based on the national schedule of vaccines. The specific vaccines provided may differ from country to country and will change over time.

BCG (Bacille Calmette-Guérin)—Anti-tuberculosis vaccine received shortly after birth.

HepB—A birth dose of hepatitis B vaccine should be given within 24 hours of birth; it is classified as given within 1 day of birth and after 1 day of birth.

DPT-HepB-Hib—A pentavalent vaccine against diphtheria, pertussis, tetanus (DPT), hepatitis B (HepB), and Haemophilus influenza type b (Hib) received in 3 doses typically at 6, 10, and 14 weeks after birth. If DPT, HepB, and Hib are not provided as a single pentavalent vaccine, each vaccine type is reported separately.

Polio—Given either as oral polio vaccine (OPV) or inactivated polio vaccine (IPV). Received in 3 doses usually given at same time as DPT-containing vaccine (6, 10, and 14 weeks after birth). In some countries, an additional birth dose of OPV (polio 0) is given. Increasingly a single dose of IPV is given at the same time as the third dose of OPV.

Pneumococcal—Pneumococcal conjugate vaccine is given in 3 doses: 2 doses before age 6 months of age, plus booster dose at age 9-15 months or on the same schedule as DPT-containing vaccine (6, 10, and 14 weeks after birth).

Rotavirus—Depending on the type of vaccine, rotavirus vaccine is given on a 2 or 3 dose schedule at the same time as DPT-containing vaccine.

Measles containing vaccine (MCV)—In countries with ongoing measles transmission, dose 1 is recommended to be given at age 9 months. In countries with low levels of measles transmission, MCV 1 is recommended to be given at age 12 months. MCV 2, where given, is usually at 15-18 months. Measles containing vaccine includes vaccines such as the measles-mumps-rubella (MMR) vaccine and the measles-rubella (MR) vaccine.

Fully vaccinated (basic antigens):

BCG, 3 doses of DPT-containing vaccine, 3 doses of polio vaccine (excluding polio vaccine given at birth), and 1 dose of MCV.

Fully vaccinated (according to national schedule):

For children age 12-23 months: BCG, HepB (birth dose), 3 doses of DPT-HepB-Hib, 3 [4] doses of OPV, 1 dose of IPV, 3 [2] doses of pneumococcal vaccine, 3 [2] doses of rotavirus vaccine, and 1 dose of MCV, according to the national vaccination schedule.

For children age 24-35 months, BCG, HepB (birth dose), 3 doses of DPT-HepB-Hib, 3 [4] doses of OPV, 1 dose of IPV, 3 [2] doses of pneumococcal vaccine, 3 [2] doses of rotavirus vaccine, and 2 doses of MCV, according to the national vaccination schedule.

No vaccinations: None of the above specified childhood vaccinations was given to the child.

Vaccinated at any time

Where the information is present on a vaccination card shown to the interviewer, the record of the vaccination is used. Where no card was shown to the interviewer or there was no record of the vaccination, the mother’s report of the vaccination is used. A vaccination is considered given if information is provided from either source (hxx in 1:3).

For multi-dose vaccines, the record of vaccines may include gaps in the vaccination history. The DHS Program assumes that the missing vaccination has not been given and renumbers the vaccines to match the number of a specific type of vaccine given. For example, if a child is recorded as having received DPT-HepB-Hib 2 only and there is no record of DPT-HepB-Hib 1, it is assumed that DPT-HepB-Hib 1 has been given, but not DPT-HepB-Hib 2. Similarly, if a child has a record with Polio 1 and Polio 3 completed, but not Polio 2, it is assumed that Polio 1 and Polio 2 have been given but not Polio 3. That is, the logic goes by the number of vaccinations known to have been given, not by the position in the record that the vaccinations are recorded.

The logic for multi-dose vaccinations is as follows:

Vacc 1: Sum of (hxx in 1:3) + (hyy in 1:3) + (hzz in 1:3) ≥ 1

Vacc 2: Sum of (hxx in 1:3) + (hyy in 1:3) + (hzz in 1:3) ≥ 2

Vacc 3: Sum of (hxx in 1:3) + (hyy in 1:3) + (hzz in 1:3) ≥ 3

Where hxx is the first vaccination in a series, hyy is the second, and hzz is the third.

For example for DPT-HepB-Hib:

DPT-HepB-Hib 1: Sum of (h3 in 1:3) + (h5 in 1:3) + (h7 in 1:3) ≥ 1

DPT-HepB-Hib 2: Sum of (h3 in 1:3) + (h5 in 1:3) + (h7 in 1:3) ≥ 2

DPT-HepB-Hib 3: Sum of (h3 in 1:3) + (h5 in 1:3) + (h7 in 1:3) ≥ 3

Vaccinated by appropriate age

A vaccination is considered to have been given at the appropriate age if the vaccination was given within the first 12 months for vaccines scheduled to be given in the first year of life and given within the first 24 months for vaccines scheduled to be given in the second year of life. Typically, all childhood vaccines reported in a DHS survey are given in the first year of life except for MCV 2, which is usually scheduled to be given in the second year of life. In some countries MCV 1 is given at 12 months and MCV 2 at 24 months or later, and the appropriate age is adjusted accordingly for these vaccines in this case.

The logic for assessing if a vaccine was given at the appropriate age is similar to that for vaccinated at any time, except for the additional test for the vaccination having been given in the first year of life or the second year of life as appropriate. This test is only possible for children with vaccination dates reported on a vaccination card. When a child does not have a vaccination card that was shown to the interviewer, an assumption is made that the ages at vaccinations for children whose mothers reported the vaccination are the same as those derived from the dates on the vaccination cards. Additionally, there may be vaccination dates that are unknown or not fully recorded on the vaccination cards, some of which provide enough information to determine if the vaccination was given by the appropriate age, while others do not. Therefore, the number of all children with the specific vaccination dose is multiplied by the proportion of that dose given before age 12 months compared with those for which it is possible to determine if the vaccination was given by the appropriate age, as determined by information taken from the vaccination card.

The calculation of this proportion requires two steps:

1)      Number of vaccinations where the vaccination was given by the appropriate age, if:

a)       Year of vaccination is the same as year of birth and vaccination was given after date of birth, or

b)      Year of vaccination equals the year of birth plus 1 (or plus 2 for MCV 2) years and

·         month of vaccination is before month of birth, or

·         month of vaccination equals month of birth and day of vaccination is before day of birth, or

c)       Year of vaccination equals the year of birth plus 1 for MCV 2 only.

2)      Number of vaccinations where it is possible to say whether the vaccination was given by the appropriate age:

a)       Year of vaccination equals year of birth and vaccination was given after date of birth, or

b)      Year of vaccination equals year of birth plus 1 (or plus 2 for MCV 2) years, and month of vaccination is given and, if month of vaccination equals month of birth, day of vaccination is also given, or

c)       Year of vaccination is any other year after the year of birth.

It is the ratio of these two that provides the proportion that is applied to the number of all children having received the specific vaccination to produce the percentage given by the appropriate age.

Denominators:

a)      Number of living children age 12–23 months (b5 = 1 & b19 in 12:23)

b)      Number of living children age 24-35 months (b5 = 1 & b19 in 24:35)

Indicator Definitions:

Indicators 1-3, 5-7: Numerator divided by denominator for the age group, multiplied by 100.

Indicators 4, 8 and Indicators 3 or 7, respectively, multiplied by the quotient of the number of vaccinations where the vaccination was given by the appropriate age (see Step 1) in Calculation above) divided by the number of vaccinations where it is possible to say whether the vaccination was given by the appropriate age (see Step 2) in Calculation above).

Handling of Missing Values

Missing vaccination card: Mother’s report of vaccination, if any, is used.

Missing vaccination on card: Use mother’s report of vaccination, if any, and otherwise assume vaccination is not given.

Missing or invalid date on vaccination card: Impute whether before or after age 12 months or before or after age 24 months according to distributions on vaccination cards with valid dates – applied in aggregate after calculation of number of children receiving each vaccine.

Missing mother’s report of vaccination or mother does not know if vaccination given: Treat as vaccine not received when no valid information is on the vaccination card.

Notes and Considerations

The complexity of the vaccination landscape and the fact that it has changed over time (and is expected to continue to do so) complicates trend analysis, and cross-country comparisons. The all basic vaccinations indicator can be used for trend analysis, although the components of this indicator too have changed over time (for example, DPT has been replaced by DPT-HepB-Hib or other DPT-containing vaccines in most countries).

In some countries, especially those of Latin America and the Commonwealth of Independent States (CIS), the recommended age for MCV 1 is at 12 months or later, compared with at 9 months in many other countries. In such cases, MCV 1 will only be reported for children age 24-35 months. Similarly, in many of these same countries, the recommended age for giving MCV 2 is at 24 months or later, in which case MCV 2 is not reported for children age 24-35 months. Similarly, other vaccines may be given at later ages according to the national vaccination schedule and will be excluded from reporting for age groups where all children in the age group have not had the opportunity to receive the vaccine.

The fully vaccinated (according to national schedule) indicator will change every time a country adds an additional vaccine to its national vaccination schedule. The age-appropriate vaccinations will vary depending on the national vaccination schedule, and the numbers of doses, the types of vaccine included, or the ages at which they are given may vary from country to country or from survey to survey.

Care needs to be taken not to confuse the oral polio vaccine (OPV) dose given at birth (called polio 0) from the OPV doses given later (polio 1, polio 2, and polio 3). Similarly, the inactivated polio dose (IPV) may be given at the same time as the third OPV dose and should not be confused with the third dose of OPV. Alternatively, IPV may entirely replace OPV or IPV may be given in combination with DPT-Hib or DPT-HepB-Hib as a pentavalent or hexavalent antigen vaccine.

Changes over Time

In some countries, especially those of Latin America, the recommended age for MCV has changed from below age 12 months to age 12 months or above. In DHS-VI and earlier, where this was the case, the age range of the children in both numerator and denominator was changed from 12-23 months to 18-29 months. Additionally, age 18 months instead of age 12 months was used as the age by which vaccinations should have taken place. However, in DHS-7 and DHS-8, The DHS Program is consistently reporting vaccination rates across the age 12-23 and 24-35 month cohorts. Thus, in the instance where a child should receive MCV 1 at age 18 months, the survey would report on whether or not a child age 24-35 months received the MCV 1, and this vaccine would not be reported for children age 12-23 months.

In surveys before DHS-7, the calculation of whether vaccinations were given in the first year of life was only calculated to the month because the day of birth of the child was not collected. Beginning in DHS-8, the calculation is performed to the day using the day, month, and year of birth and of vaccination.

The nomenclature used for key vaccination coverage indicators has also changed over time. Following guidance developed under the auspices of WHO’s Expanded Programme on Immunization, beginning in DHS-8, the term “fully vaccinated (basic antigens)” replaces “all basic vaccinations” and the term “fully vaccinated (according to national schedule)” replaces “all age appropriate vaccinations”.

References

Assaf, S., L. Horton, M. Bornstein, and T. Pullum. 2017. Levels and Trends of Maternal and Child Health Indicators in 11 Middle East and North African Countries. DHS Comparative Report No. 46. Rockville, Maryland, USA: ICF. https://www.dhsprogram.com/publications/publication-CR46-Comparative-Reports.cfm

Cutts, F.T., P. Claquin, M.C. Danovaro-Holliday, D.A. Rhoda. 2016. “Monitoring vaccination coverage: Defining the role of surveys.” Vaccine 34: 4103-4109. https://www.ncbi.nlm.nih.gov/pubmed/27349841

Cutts, F.T., H.S. Izurieta, D.A. Rhoda. 2013. “Measuring Coverage in MNCH: Design, Implementation, and Interpretation Challenges Associated with Tracking Vaccination Coverage Using Household Surveys.” PLOS Medicine 10: 1-11. https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1001404

Rutstein, S.O., S. Staveteig, R. Winter, and J. Yourkavitch. 2016. Urban child poverty, health, and survival in low- and middle-income countries. DHS Comparative Reports No. 40. Rockville, Maryland, USA: ICF International. https://www.dhsprogram.com/publications/publication-CR40-Comparative-Reports.cfm

WHO, UNICEF, World Bank. 2009. State of the world’s vaccines and immunization, 3rd ed. Geneva, World Health Organization. https://apps.who.int/iris/handle/10665/44169

World Health Organization. 2018. Global reference list of 100 core health indicators. Geneva: World Health Organization. https://apps.who.int/iris/handle/10665/259951

White paper commissioned by WHO’s Expanded Programme on Immunization. 2019 Harmonizing vaccination coverage measures in household surveys: a primer.

https://cdn.who.int/media/docs/default-source/immunization/immunization-coverage/surveys_white_paper_immunization_2019.pdf?sfvrsn=7e0fb0ae_9

UNICEF. 2018. Immunization. https://data.unicef.org/topic/child-health/immunization/

WHO. WHO vaccine-preventable diseases: monitoring system. 2018 global summary. 2018.

https://immunizationdata.who.int/

Resources

DHS-8 Tabulation plan: Tables 10.3 and 10.4

API Indicator IDs:

By source of information:

CH_VACS_C_BCG, CH_VACS_C_DP1, CH_VACS_C_DP2, CH_VACS_C_DP3, CH_VACS_C_OP0, CH_VACS_C_OP1, CH_VACS_C_OP2, CH_VACS_C_OP3, CH_VACS_C_MSL, CH_VACS_C_MS2, CH_VACS_C_HP0, CH_VACS_C_HP1, CH_VACS_C_HP2, CH_VACS_C_HP3, CH_VACS_C_HB1, CH_VACS_C_HB2, CH_VACS_C_HB3, CH_VACS_C_PN1, CH_VACS_C_PN2, CH_VACS_C_PN3, CH_VACS_C_RT1, CH_VACS_C_RT2, CH_VACS_C_RT3, CH_VACS_C_BAS, CH_VACS_C_APP, CH_VACS_C_NON

(API link, STATcompiler link)

By background characteristics:

CH_VACC_C_BCG, CH_VACC_C_DP1, CH_VACC_C_DP2, CH_VACC_C_DP3, CH_VACC_C_OP0, CH_VACC_C_OP1, CH_VACC_C_OP2, CH_VACC_C_OP3, CH_VACC_C_MSL, CH_VACC_C_MS2, CH_VACC_C_HP0, CH_VACC_C_HP1, CH_VACC_C_HP2, CH_VACC_C_HP3, CH_VACC_C_HB1, CH_VACC_C_HB2, CH_VACC_C_HB3, CH_VACC_C_PN1, CH_VACC_C_PN2, CH_VACC_C_PN3, CH_VACC_C_RT1, CH_VACC_C_RT2, CH_VACC_C_RT3, CH_VACC_C_BAS, CH_VACC_C_APP, CH_VACC_C_NON

(API link, STATcompiler link)

SDG Indicator 3.b.1: Proportion of the target population covered by all vaccines included in their national programme

WHO 100 Core Health Indicators: National vaccination rate by vaccine

MICS6 Indicator TC.1: Tuberculosis immunization coverage

MICS6 Indicator TC.2: Polio immunization coverage

MICS6 Indicator TC.3: Diphtheria, tetanus, and pertussis (DTP) immunization coverage

MICS6 Indicator TC.4: Hepatitis B immunization coverage

MICS6 Indicator TC.5: Haemophilus influenza type B (Hib) immunization coverage

MICS6 Indicator TC.6: Pneumococcal (conjugate) immunization coverage

MICS6 Indicator TC.7: Rotavirus immunization coverage

MICS6 Indicator TC.10: Measles immunization coverage

MICS6 Indicator TC.11: Full immunization coverage

Percentage of children who ever had a vaccination card and who had a vaccination card seen

Definition

1)      Percentage of children age 12–23 months who ever had a vaccination card.

2)      Percentage of children age 12–23 months who had a vaccination card seen.

3)      Percentage of children age 24-35 months who ever had a vaccination card.

4)      Percentage of children age 24-35 months who had a vaccination card seen.

Coverage:

Population base: Living children age 12–23 months and 24-35 months (KR file)

Time period: 3 years preceding the survey

Numerators:

1)      Number of living children age 12-23 months who ever had a vaccination card (b5 = 1 & h1 in 1:3)

2)      Number of living children age 12-23 months whose vaccination card was seen at the time of the interview (b5 = 1 & h1 = 1)

3)      Number of living children age 24-35 months who ever had a vaccination card (b5 = 1 & h1 in 1:3)

4)      Number of living children age 24-35 months whose vaccination card was seen at the time of the interview (b5 = 1 & h1 = 1)

Denominators:

a)       Number of living children age 12-23 months (b5 = 1 & b19 in 12:23)

b)      Number of living children age 24-35 months (b5 = 1 & b19 in 24:35)

Variables: KR file.

Calculation

Numerator divided by the denominator, multiplied by 100.

Handling of Missing Values

Missing data or “don’t know” response for whether ever had a card or whether it was seen are excluded from numerators.

Notes and Considerations

The term vaccination card encompasses card, booklet, or other home-based record in which vaccination information has been recorded.

Changes over Time

Percentage who ever had a card was first included in DHS-7.

References

Brown, D.W., and M. Gacic-Dobo. 2015. “Home-based record prevalence among children age 12-23 months from 180 demographic and health surveys.” Vaccine. 33: 2584-2593.

https://www.sciencedirect.com/science/article/pii/S0264410X15004405

Resources

DHS-8 Tabulation plan: Table 10.2

API Indicator IDs:

CH_VACP_C_EV1, CH_VACP_C_SN1

(API link, STATcompiler link)

Percentage of children age 12-23 months and 24-35 months by source of most vaccinations

Definition

1)      Among children age 12-23 months who received at least one vaccination, percent distribution of children by source of most vaccinations.

2)      Among children age 23-35 months who received at least one vaccination, percent distribution of children by source of most vaccinations.

Coverage:

Population base: Living children age 12–23 months and 24-35 months (KR file)

Time period: 3 years before survey; at the time of interview

Numerators:

1)      Number of living children age 12-23 months whose source of most vaccinations was: public medical sector, private medical sector (non-NGO), private medical sector (NGO), other (b5 = 1 & b19)

2)      Number of living children age 24-35 months whose source of most vaccinations was: public medical sector, private medical sector (non-NGO), private medical sector (NGO), other (b5 = 1 & b19)

Denominators:

a)       Number of living children age 12-23 months who received at least one vaccination (b5 = 1 & b19 in 12:23)

b)      Number of living children age 24-35 months who received at least vaccination (b5 = 1 & b19 in 24:35)

Variables: KR file.

Calculation

Numerator divided by the denominator, multiplied by 100.

Source of most vaccination is categorized as public medical sector (b19 in 10:19), private medical sector (non-NGO) (b19 in 20:29), private medical sector (NGO) (b19 in 30:39), other (b19 in 40:46)

Handling of Missing Values

“Don’t know” responses and missing values are included in the “don’t know” category in the percent distributions. Percent distributions add up to 100 percent.

Changes over Time

Information on source of vaccinations was introduced in DHS-8.

Resources

DHS-8 Tabulation plan: Table 10.5

API Indicator IDs:

TBD

(API link TBD, STATcompiler link TBD)