• Immunization prevents illness, disability and death from vaccine-preventable diseases including cervical cancer, diphtheria, hepatitis B, measles, mumps, pertussis (whooping cough), pneumonia, polio, rota virus diarrhoea, rubella and tetanus.
  • Global vaccination coverage remains at 85%, with no significant changes during the past few years.
  • Uptake of new and underused vaccines is increasing.
  • An additional 1.5 million deaths could be avoided, however if global immunization coverage improves.
  • An estimated 19.9 million children under the age of one did not receive DTP3 vaccine.

Overview

Global vaccination coverage – the proportion of the world’s children who receive recommended vaccines – has remained the same over the past few years.

During 2017, about  85% of infants worldwide (116.2 million infants) 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 2017, 123 countries had reached at least 90% coverage of DTP3 vaccine.

Global immunization coverage 2017

A summary of global vaccination coverage in 2017 follows.

Haemophilus influenzae type b (Hib) causes meningitis and pneumonia. Hib vaccine had been introduced in 191 countries by the end of  2017. Global coverage with 3 doses of Hib vaccine is estimated at  72%. There is great variation between regions. In the WHO Region of the Americas, coverage is estimated at  91%, while it is only 28% in the WHO Western Pacific Region. The WHO South-East Asia Region raised coverage from 80% in 2016 to 86% in 2017.

Hepatitis B is a viral infection that attacks the liver. Hepatitis B vaccine for infants had been introduced nationwide in 187 countries by the end of 2017. Global coverage with 3 doses of hepatitis B vaccine is estimated at 84% and is as high as 93% in the Western Pacific. In addition, 105 countries introduced one dose of hepatitis B vaccine to newborns within the first 24 hours of life, and the global coverage is  43%.

Human papillomavirus (HPV) 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. HPV vaccine was introduced in  80 countries by the end of 2017, excluding four countries with introduction in some parts of the country.

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 2017, 85% of children had received one dose of measles vaccine by their second birthday, and 167 countries had included a second dose as part of routine immunization and 67% of children received two doses of measles vaccine according to national immunization schedules.

Meningitis A is an infection that can cause severe brain damage and is often deadly. By the end of 2017 – 7 years after its introduction – more than 280 million people in African countries affected by the disease had been vaccinated with MenAfriVac, a revolutionary vaccine developed by WHO and PATH. In 2012, MenAfriVac became the first vaccine to gain approval for travel outside the cold chain – for as long as four days without refrigeration and at temperatures of up to 40°C. Ghana and Sudan were the first two countries to include the MenAfriVac in their routine immunization schedule in 2016, followed by Burkina Faso, Central African Republic, Chad, Mali and Niger in 2017.

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 122 countries by the end of 2017.

Pneumococcal diseases include pneumonia, meningitis and febrile bacteraemia, as well as otitis media, sinusitis and bronchitis. Pneumococcal vaccine had been introduced in 135 countries by the end of 2017, including  five in some parts of the country, and global coverage was estimated at 44%.

Polio is a highly infectious viral disease that can cause irreversible paralysis. In 2017, 85% of infants around the world received three doses of polio vaccine. Targeted for global eradication, polio has been stopped in all countries except for 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 91 countries by the end of 2017, including six in some parts of the country, and global coverage was estimated at 28%.

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 162 countries by the end of 2017, and global coverage was estimated at 52%.

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 2017. An estimated 85% of newborns were protected through immunization. Maternal and neonatal tetanus persist as public health problems in 14 countries, mainly in Africa and Asia.

Yellow fever is an acute viral haemorrhagic disease transmitted by infected mosquitoes. As of 2017, yellow fever vaccine had been introduced in routine infant immunization programmes in 36 of the 42 countries and territories at risk for yellow fever in Africa and the Americas. In these 42 countries and territories, coverage is estimated at  43%.

Key challenges

In 2017, an estimated  19.9 million infants worldwide were not reached with routine immunization services such as 3 doses of DTP vaccine. Around 60% of these children live in 10 countries: Afghanistan, Angola, the Democratic Republic of the Congo, Ethiopia, India, Indonesia, Iraq, Nigeria, Pakistan and South Africa.

Monitoring data at sub national 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.

culled @ who

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