Number of one-year-olds who are not fully vaccinated against in Sierra Leone
Sierra Leone: Number of one-year-olds who are not fully vaccinated against was 21,194 one-year-olds in 2023. ◆ Volatile
Number of one-year-olds who are not fully vaccinated against diphtheria, pertussis and tetanus in Sierra Leone, 1999–2023
Source: WHO & UNICEF (2026); UN, World Population Prospects (2024) – processed by Our World in Data. Measured in one-year-olds.
Analysis
The most recent figure for number of one-year-olds who are not fully vaccinated against diphtheria, pertussis and tetanus in Sierra Leone is 21,194 one-year-olds, measured in 2023.
That represents a change of up 0.7% on the previous year and up 21.3% over ten years.
Over the whole period, number of one-year-olds who are not fully vaccinated against diphtheria, pertussis and tetanus in Sierra Leone peaked at 106,434 one-year-olds in 2001 and was at its lowest, 11,358 one-year-olds, in 2019.
Sierra Leone ranks 79th of 195 countries on this measure, in the middle of the range.
The series is highly variable year to year, so single readings are best treated with caution.
Number of one-year-olds who are not fully vaccinated against in Sierra Leone, year by year
| Year | one-year-olds | Change |
|---|---|---|
| 1999 | 90,195 one-year-olds | — |
| 2000 | 90,782 one-year-olds | +0.7% |
| 2001 | 106,434 one-year-olds | +17.2% |
| 2002 | 85,236 one-year-olds | -19.9% |
| 2003 | 50,757 one-year-olds | -40.5% |
| 2004 | 67,443 one-year-olds | +32.9% |
| 2005 | 68,044 one-year-olds | +0.9% |
| 2006 | 70,364 one-year-olds | +3.4% |
| 2007 | 71,496 one-year-olds | +1.6% |
| 2008 | 46,545 one-year-olds | -34.9% |
| 2009 | 33,001 one-year-olds | -29.1% |
| 2010 | 29,424 one-year-olds | -10.8% |
| 2011 | 23,430 one-year-olds | -20.4% |
| 2012 | 19,424 one-year-olds | -17.1% |
| 2013 | 17,478 one-year-olds | -10.0% |
| 2014 | 37,268 one-year-olds | +113.2% |
| 2015 | 30,646 one-year-olds | -17.8% |
| 2016 | 35,045 one-year-olds | +14.4% |
| 2017 | 22,073 one-year-olds | -37.0% |
| 2018 | 15,681 one-year-olds | -29.0% |
| 2019 | 11,358 one-year-olds | -27.6% |
| 2020 | 20,688 one-year-olds | +82.1% |
| 2021 | 18,560 one-year-olds | -10.3% |
| 2022 | 21,040 one-year-olds | +13.4% |
| 2023 | 21,194 one-year-olds | +0.7% |
Sierra Leone compared with similar countries
- Sierra Leone's 21,194 one-year-olds is below the median for low income countries, which is 144,384 one-year-olds, 15% of the median. (25 countries reporting)
- Sierra Leone's 21,194 one-year-olds is below the median for Sub-Saharan Africa, which is 52,290 one-year-olds, 41% of the median. (48 countries reporting)
Averages by decade
| Decade | Average | Lowest | Highest | Years |
|---|---|---|---|---|
| 1990s | 90,195 one-year-olds | 90,195 one-year-olds | 90,195 one-year-olds | 1 |
| 2000s | 69,010 one-year-olds | 33,001 one-year-olds | 106,434 one-year-olds | 10 |
| 2010s | 24,183 one-year-olds | 11,358 one-year-olds | 37,268 one-year-olds | 10 |
| 2020s | 20,370 one-year-olds | 18,560 one-year-olds | 21,194 one-year-olds | 4 |
Countries ranked near Sierra Leone
More health data for Sierra Leone
- Un projection of annual infant deaths, annual growth rate -2.34 % change on previous year (2100)
- Heat deaths vs projected death rates, annual growth rate 0.773 % change on previous year (2090)
- Number of infants who die before age 1 4,209 deaths (2100)
- Neonatal tetanus - number of reported cases, gaps filled 38 (2025)
- Population ages 00-04, female, annual growth rate 0.6447 % change on previous year (2025)
- Population ages 00-04, female, per unit of GDP 0.0001 units per US$ of GDP (2025)
- Population ages 00-04, female, per capita 0.0663 units per person (2025)
- Population ages 00-04, male, annual growth rate 0.6611 % change on previous year (2025)
- Population ages 00-04, male, per unit of GDP 0.0001 units per US$ of GDP (2025)
- Population ages 00-04, male, per capita 0.0676 units per person (2025)
Frequently asked questions
- What is number of one-year-olds who are not fully vaccinated against diphtheria, pertussis and tetanus in Sierra Leone?
- Number of one-year-olds who are not fully vaccinated against diphtheria, pertussis and tetanus in Sierra Leone was 21,194 one-year-olds in 2023, according to WHO & UNICEF (2026); UN, World Population Prospects (2024) – processed by Our World in Data.
- What is the highest number of one-year-olds who are not fully vaccinated against diphtheria, pertussis and tetanus recorded in Sierra Leone?
- The highest recorded value was 106,434 one-year-olds in 2001.
- What is the lowest number of one-year-olds who are not fully vaccinated against diphtheria, pertussis and tetanus recorded in Sierra Leone?
- The lowest recorded value was 11,358 one-year-olds in 2019.
- How does Sierra Leone rank for number of one-year-olds who are not fully vaccinated against diphtheria, pertussis and tetanus?
- Sierra Leone ranks 79th out of 195 countries with data for 2023.
- Is number of one-year-olds who are not fully vaccinated against diphtheria, pertussis and tetanus rising or falling in Sierra Leone?
- Over the last ten years it is up 21.3%. The long-run trend across the full record is volatile.
- Where does this Sierra Leone data come from?
- The figures come from WHO & UNICEF (2026); UN, World Population Prospects (2024) – processed by Our World in Data, published as part of Number of one-year-olds who are not fully vaccinated against diphtheria, pertussis and tetanus. Statizoid updates them automatically from the source API.
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About this data
Number of one-year-olds who have not had three doses of the combined diphtheria, tetanus and pertussis vaccine in a given year.