Overview
While immunization is one of the most successful public health interventions, coverage plateaued in the decade prior to COVID-19. The COVID-19 pandemic, associated disruptions, and vaccination efforts strained health systems in 2020 and 2021, resulting in dramatic setbacks. However, from a global perspective recovery is on the horizon: in 2022 diptheria-pertussis-tetanus (DTP) immunization coverage almost recovered to 2019 levels.
During 2022, about 84% of infants worldwide (110 million) received 3 doses of diphtheria-tetanus-pertussis (DTP3) vaccine, protecting them against infectious diseases that can cause serious illness and disability or be fatal. These global figures however hide significant disparity become countries of different income strata, with low-income countries lagging behind.
Measles, because of its high transmissibility, acts as an early warning system, quickly exposing any immunity gaps in the population. Still, 21.9 million children missed their routine first dose of measles, far from 2019 levels of 19.2 million.
Global immunization coverage 2022
A summary of global vaccination coverage in 2022 follows.
Haemophilus influenzae type b (Hib) causes meningitis and pneumonia. Hib vaccine had been introduced in 193 Member States by the end of 2022. Global coverage with 3 doses of Hib vaccine is estimated at 76%. There is great variation between regions. The WHO European Region and South-East Asia Region are estimated to have 93% coverage and 91% coverage, respectively, while it is only 32% in the WHO Western Pacific Region.
Hepatitis B is a viral infection that attacks the liver. Hepatitis B vaccine for infants had been introduced nationwide in 190 Member States by the end of 2022. Global coverage with 3 doses of hepatitis B vaccine is estimated at 84%. In addition, 113 Member States introduced nationwide 1 dose of hepatitis B vaccine to newborns within the first 24 hours of life. Global coverage is 45% and is as high as 80% in the WHO Western Pacific Region, while it is only estimated to be at 18% in the WHO African Region.
Human papillomavirus (HPV) is the most common viral infection of the reproductive tract and can cause cervical cancer in women, other types of cancer, and genital warts in both men and women. One hundred thirty Member States had the HPV vaccine in their national immunization services by the end of 2022, including 14 new introductions. Since many large countries have not yet introduced the vaccine and vaccine coverage continues to be suboptimal in 2022 in many countries, global coverage with the first dose of HPV among girls is now estimated at 21%. This is a proportionally large increase from 16% in 2021 and was driven in particular by the effect of new introductions and programmes that resumed after interruptions.
Bacterial meningitis is an infection that is often deadly and leaves 1 in 5 individuals with long-term devastating sequelae after the acute infection. Before the introduction of MenAfriVac in 2010 – a revolutionary vaccine – Neisseria meningitidis serogroup A (NmA) accounted for 80–85% of meningitis epidemics in the African meningitis belt. By the end of 2022, more than 350 million people in 24 out of the 26 countries in the meningitis belt had been vaccinated with MenAfriVac through campaigns and 14 countries had included MenAfriVac in their routine immunization schedule. No case of NmA meningitis has been confirmed since 2017 in the meningitis belt.
Measles is a highly contagious disease caused by a virus, which usually results in a high fever and rash, and can lead to blindness, encephalitis or death. By the end of 2022, 83% of children had received 1 dose of measles-containing vaccine by their second birthday, and 188 Member States had included a second dose as part of routine immunization and 74% of children received 2 doses of measles vaccine according to national immunization schedules.
Mumps is a highly contagious virus that causes painful swelling at the side of the face under the ears (the parotid glands), fever, headache and muscle aches. It can lead to viral meningitis. Mumps vaccine had been introduced nationwide in 123 Member States by the end of 2022.
Pneumococcal diseases include pneumonia, meningitis and febrile bacteraemia, as well as otitis media, sinusitis and bronchitis. Pneumococcal vaccine had been introduced in 155 Member States by the end of 2022 and global third dose coverage was estimated at 60%. There is great variation between regions. The WHO European Region is estimated to have 83% coverage, while it is only 23% in the WHO Western Pacific Region.
Polio is a highly infectious viral disease that can cause irreversible paralysis. In 2022, 84% of infants around the world received 3 doses of polio vaccine. In 2022, the coverage of infants receiving their first dose of inactivated polio vaccine (IPV) in countries that are still using oral polio vaccine (OPV) is estimated at 84% as well. Targeted for global eradication, polio has been stopped in all countries except for Afghanistan and Pakistan. Until poliovirus transmission is interrupted in these countries, all countries remain at risk of importation of polio, especially vulnerable countries with weak public health and immunization services and travel or trade links to endemic countries.
Rotaviruses are the most common cause of severe diarrhoeal disease in young children throughout the world. Rotavirus vaccine was introduced in 121 countries by the end of 2022, including 3 in some parts of the country. Global coverage was estimated at 51%.
Rubella is a viral disease which is usually mild in children, but infection during early pregnancy may cause fetal death or congenital rubella syndrome, which can lead to defects of the brain, heart, eyes and ears. Rubella vaccine was introduced nationwide in 174 Member States by the end of 2022, and global coverage was estimated at 68%.
Tetanus is caused by a bacterium which grows in the absence of oxygen, for example in dirty wounds or the umbilical cord if it is not kept clean. The spores of C. tetani are present in the environment irrespective of geographical location. It produces a toxin which can cause serious complications or death. Maternal and neonatal tetanus persist as public health problems in 12 countries, mainly in Africa and Asia.
Yellow fever is an acute viral haemorrhagic disease transmitted by infected mosquitoes. As of 2022, yellow fever vaccine had been introduced in routine infant immunization programmes in 37 of the 40 countries and territories at risk for yellow fever in Africa and the Americas. In these 40 countries and territories, coverage is estimated at 45%.
Key challenges
In 2022, 14.3 million infants did not receive an initial dose of DTP vaccine, pointing to a lack of access to immunization and other health services, and an additional 6.2 million are partially vaccinated. Of the 20.5 million, just under 60% of these children live in 10 countries: Angola, Brazil, the Democratic Republic of the Congo, Ethiopia, India, Indonesia, Mozambique, Nigeria, Pakistan and the Philippines.
Monitoring data at subnational levels is critical to helping countries prioritize and tailor vaccination strategies and operational plans to address immunization gaps and reach every person with life-saving vaccines.
WHO response
WHO is working with countries and partners to improve global vaccination coverage, including through these initiatives adopted by the World Health Assembly in August 2020.
Immunization Agenda 2030
IA2030 sets an ambitious, overarching global vision and strategy for vaccines and immunization for the decade 2021–2030. It was co-created with thousands of contributions from countries and organizations around the world. It draws on lessons from the past decade and acknowledges continuing and new challenges posed by infectious diseases (e.g. Ebola, COVID-19).
The strategy has been designed to respond to the interests of every country and intends to inspire and align the activities of community, national, regional and global stakeholders towards achieving a world where everyone, everywhere fully benefits from vaccines for good health and well-being. IA2030 is operationalized through regional and national strategies and mechanisms to ensure ownership and accountability and a monitoring and evaluation framework to guide country implementation.
In 2020, the World Health Assembly adopted the global strategy towards eliminating cervical cancer. In this strategy, the first of the 3 pillars require the introduction of the HPV vaccine in all countries and has set a target of reaching 90% coverage. With introduction currently in 67% of Member States, large investments towards introduction in low and middle-income countries will be required in the next 10 years as well as programme improvements to reach the 90% coverage targets in low and high-income settings alike will be required to reach the 2030 targets.
