- Immunization prevents illness, disability and death from vaccine-preventable diseases including cervical cancer, diphtheria, hepatitis B, measles, mumps, pertussis (whooping cough), pneumonia, polio, rotavirus diarrhoea, rubella and tetanus.
- Global vaccination coverage is generally holding steady.
- Uptake of new and underused vaccines is increasing.
- Immunization currently averts an estimated 2 to 3 million deaths every year. An additional 1.5 million deaths could be avoided, however, if global vaccination coverage improves.
- An estimated 19.4 million infants worldwide are still missing out on basic vaccines.
Immunization averts an estimated 2 to 3 million deaths every year from diphtheria, tetanus, pertussis (whooping cough), and measles; however, an additional 1.5 million deaths could be avoided if global vaccination coverage improves. Global vaccination coverage – the proportion of the world’s children who receive recommended vaccines – has remained steady for the past few years.
During 2015, about 86% (116 million) of infants worldwide received 3 doses of diphtheria-tetanus-pertussis (DTP3) vaccine, protecting them against infectious diseases that can cause serious illness and disability or be fatal. By 2015, 126 countries had reached at least 90% coverage of DTP3 vaccine.
Global immunization coverage 2015
Haemophilus influenzae type b (Hib) causes meningitis and pneumonia. Hib vaccine had been introduced in 191 countries by the end of 2015. Global coverage with 3 doses of Hib vaccine is estimated at 64%. There is great variation between regions. In the Americas, coverage is estimated at 90%, while it is only 25% and 56% in the Western Pacific and South-East Asia Regions respectively.
Hepatitis B is a viral infection that attacks the liver. Hepatitis B vaccine for infants had been introduced nationwide in 185 countries by the end of 2015. Global coverage with 3 doses of hepatitis B vaccine is estimated at 83% and is as high as 90% in the Western Pacific. In addition, 96 countries introduced one dose of hepatitis B vaccine to newborns within the first 24 hours of life, and the global coverage is 39%.
Human papillomavirus is the most common viral infection of the reproductive tract, and can cause cervical cancer, other types of cancer, and genital warts in both men and women. Human papillomavirus vaccine was introduced in 66 countries by the end of 2015.
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 2015, 85% of children had received 1 dose of measles vaccine by their second birthday, and 160 countries had included a second dose as part of routine immunization and 61% of children received 2 doses of measles vaccine according to national immunization schedule.
Meningitis A is an infection that can cause severe brain damage and is often deadly. By the end of 2015 – 5 years after its introduction – more than 235 million people in African countries affected by the disease had been vaccinated with MenAfriVac, a vaccine developed by WHO and PATH.
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 121 countries by the end of 2015.
Pneumococcal diseases include pneumonia, meningitis and febrile bacteraemia, as well as otitis media, sinusitis and bronchitis. Pneumococcal vaccine had been introduced in 129 countries by the end of 2015, and global coverage was estimated at 37%.
Polio is a highly infectious viral disease that can cause irreversible paralysis. In 2015, 86% of infants around the world received 3 doses of polio vaccine. Targeted for global eradication, polio has been stopped in all countries except for 3: Afghanistan, Pakistan and Nigeria. Polio-free countries have been infected by imported virus, and all countries – especially those experiencing conflict and instability – remain at risk until polio is fully eradicated.
Rotaviruses are the most common cause of severe diarrhoeal disease in young children throughout the world. Rotavirus vaccine was introduced in 84 countries by the end of 2015, and global coverage was estimated at 23%.
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 147 countries by the end of 2015 and global coverage was estimated at 46%.
Tetanus is caused by a bacterium which grows in the absence of oxygen, for example in dirty wounds or in 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. The vaccine to prevent maternal and neonatal tetanus had been introduced in 106 countries by the end of 2015. An estimated 83% of newborns were protected through immunization. Maternal and neonatal tetanus persist as public health problems in 19 countries, mainly in Africa and Asia.
Yellow fever is an acute viral haemorrhagic disease transmitted by infected mosquitoes. As of 2015, yellow fever vaccine had been introduced in routine infant immunization programmes in 35 of the 42 countries and territories at risk for yellow fever in Africa and the Americas.
Last year, the Strategic Advisory Group of Experts on immunization (SAGE) identified 5 factors to achieving results in immunization coverage:
- quality and use of data
- community involvement
- better access to immunization services for marginalized and displaced populations
- strong health systems
- access to vaccines in all places at all times.
In 2015, an estimated 19.4 million infants worldwide were not reached with routine immunization services such as DTP3 vaccine. Around 60% of these children live in 10 countries: Angola, the Democratic Republic of the Congo, Ethiopia, India, Indonesia, Iraq, Nigeria, Pakistan, the Philippines, and Ukraine.
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 lifesaving vaccines.
WHO is working with countries and partners to improve global vaccination coverage, including through these initiatives adopted by the World Health Assembly in May 2012.
The Global Vaccine Action Plan
The Global Vaccine Action Plan (GVAP) is a roadmap to prevent millions of deaths through more equitable access to vaccines. Countries are aiming to achieve vaccination coverage of at least 90% nationally and at least 80% in every district by 2020. While the GVAP should accelerate control of all vaccine-preventable diseases, polio eradication is set as the first milestone. It also aims to spur research and development for the next generation of vaccines.
WHO is leading efforts to support regions and countries as they adapt the GVAP for implementation. In April 2016, WHO warned that 5 out of the 6 GVAP targets were off-track, with only 1 target on the introduction of underutilized vaccines showing sufficient progress. This finding was based on the independent assessment report by SAGE.
The GVAP recommends 3 key steps for closing the immunization gap:
- integrating immunization with other health services, such as postnatal care for mothers and babies;
- strengthening health systems so that vaccines continue to be given even in times of crisis; and
- ensuring that everyone can access vaccines and afford to pay for them.
World Immunization Week
The last week of April each year is marked by WHO and partners as World Immunization Week. It aims to accelerate action to increase awareness and demand for immunization and improve vaccination delivery services so that people everywhere can be protected against deadly diseases.
In 2016, under the global slogan "Close the immunization gap”, the campaign focused on immunization for all throughout life. .More than 180 countries, territories and areas marked the week with activities including vaccination campaigns, training workshops, round-table discussions and public information campaigns. The theme for World Immunization Week 2017 is #VaccinesWork.