Vaccination has been proven to help children prevent and survive varying diseases, and live a long and healthy life, irrespective of their place of birth.
However, the world, in recent times, has been facing lots of challenges convincing people about the importance of the small liquid in vaccine bottles.
This has made health experts around the world struggle with containing the spread of killer diseases, most of which are vaccine-preventable.
Developing countries such as Nigeria, Democratic Republic of Congo, Afghanistan, Pakistan, India, among others, have not stopped reporting cases of vaccine-preventable diseases, despite the availability of these vaccines.
Childhood killer diseases such as pneumonia, measles, meningitis, cholera among others have become epidemics and are still far from being over in most of these countries.
Meanwhile, developed countries like Ukraine, England, the US, which have made progress in the elimination of most of the preventable diseases, are, in recent times, beginning to report new cases of these diseases.
In 2019, the health community suffered a setback in health safety due to the resurgence of polio and measles in some countries where these diseases were once eliminated.
Four countries - Albania, Czech Republic, Greece and the United Kingdom, which had eradicated the disease, lost their measles free certification due to the emergence of the disease with their territories.
Also, the Philippines and Malaysia suffered a setback in polio eradication as new cases of circulating vaccine-derived polio were reported after so many years.
Though Nigeria has successfully attained three years without a reported case of wild polio virus in the country, new polio challenges are arising - particularly the circulating vaccine derived polio (cVDPv).
While some countries have been suffering setbacks, Nigeria in its own case, is still struggling with effective routine immunisation coverage for most of its children under the age of five.
The World Health Organisation has blamed the resurgence on the low compliance to vaccination, vaccine hoax, vaccine hesitancy and low immunisation culture.
A 2018 WHO report on global immunisation estimated that 19.4 million children worldwide are missed out on lifesaving immunisation services such as three doses of DTP vaccine (DTP is a combination vaccine against three infectious diseases in humans: diphtheria, pertussis (whooping cough), and tetanus).
About 60 per cent of these children live in 10 countries- Angola, Brazil, Democratic Republic of Congo (DRC), Ethiopia, India, Indonesia, Nigeria, Pakistan, the Philippines and Vietnam.
Meanwhile, the 2018 Nigeria Demographic Health Survey (NDHS), shows that the national immunisation coverage rate is still very low.
According to the survey, only 31 per cent of the children with ages 12 to 23 months received all basic vaccinations at the time before the survey, while 28 per cent received the basic vaccination by the appropriate age of 12 months and 19 per cent received no vaccination at all.
Immunisation coverage in a country is one of the indicators used to monitor progress towards a reduction in child morbidity and mortality.
As it stands, Nigeria is one of the countries in the world with the highest childhood mortality rate.
According to NDHS, the infant mortality rate was 67 per 1,000 for the five-year period preceding the survey, while under-five mortality rate was 132 deaths per 1,000 live births. This implies that more than one in eight children in Nigeria dies before their fifth birthday.
Many of these deaths are related to childhood diseases (measles, meningitis, cholera, pneumonia, diarrhoea, measles, tetanus, and polio which could have been prevented by a shot of vaccines.
WHO Director-General, Tedros Ghebreyesus, said current world vaccination status needs to be improved as it is unacceptable that while most children are being vaccinated, far too many are left behind.
According to him, it is often those who are most at risk, the poorest, and the most marginalised, those in areas of conflict or forced from their homes- who are persistently missed.
"If these children do get sick, they are (at) risk of the severest health consequences and least likely to access life-saving treatment and care," he said.
Recommended childhood vaccines
Based on the recommended WHO childhood vaccination schedule, a child from age 0 to two is expected to receive vaccines which can protect them against 13 diseases.
The first batch of vaccines is expected to be given at birth. The child is expected to receive three vaccines which are expected to protect against hepatitis B, Polio and Tuberculosis.
At six weeks, the child is to be given another set of vaccines, which covers for four more diseases and second dose for two.
While NDHS figures shows that there has been an improvement in vaccination coverage in Nigeria over the last ten years, health experts believe Nigeria still has a long way in terms of immunisation coverage.
This is due to the periodic infectious outbreak in the country and the numbers of suspected, confirmed cases and deaths recorded from such outbreaks.
According to NDHS, the percentage of children ages 12 to 23 months who received all basic vaccination increased from 23 per cent in 2008 to 31 per cent in 2018.
The percentage of the children who received none of the basic vaccinations declined from 29 per cent to 19 per cent during the same period.
While this trend shows improvement, it still falls short of the Sustainable Development Goal three, whose target is for countries to achieve 90 per cent coverage of all basic vaccinations among children ages 12 to 23 months.
A professor of virology, Oyewale Tomori, said Nigeria would reduce most of its health challenges if immunisation routine is observed diligently.
Mr Tomori, however, said this can only be achieved through dedication on the part of the government.
He said Nigeria was able to attain a commendable status in its fight against wild polio because of the commitment of the government which translated to commitment on the part of the caregivers and community.
"The government needs to put in (the) same level of commitment the made in polio eradication to all types of vaccinations for the country to have a head way.
"Without proper monitoring and evaluation process for immunisation, Nigeria will not be able to make much progress," he said.
Despite the known benefits of vaccines, many Nigerians (both children and adults) do not present themselves for vaccination.
Mr Ghebreyesus said the global rise in vaccine hesitancy and anti-vaccine movement has also affected many parents' choice of presenting their children for vaccination.
The UN health agency said vaccine hesitancy is the reluctance or refusal to vaccinate, despite the availability of vaccines.
A WHO vaccine advisory group identified complacency, inconvenience in accessing vaccines and lack of confidence as key reasons for the hesitancy.
An example is the yellow fever vaccination which is one of the compulsory travelling requirements within African states. Evidence has shown that most Nigerian travellers after paying for the service, shun the vaccine and only collect the yellow card.
The non-compliance for vaccination is also evident even in places where the government provides the vaccines.
The government, in collaboration with development partners such as GAVI, and WHO have been providing vaccines for childhood routine immunisation in the country, but much is yet to be achieved as regards the immunisation rate in the country.
Unfortunately, the non-compliance of parents and health care givers to routine immunisation has been creating problems in the health sector in Nigeria.
This has been putting a strain on the already burdened health sector as there are constant cases of outbreak of these diseases.
The reluctance of some parents and caregivers to comply with vaccination schedules for children has also led to the resurgence of old diseases such as yellow fever, which was on the brink of eradication.
Diseases to vaccines
1. Haemophilus Influenzae type b (Hib) - causes meningitis and pneumonia. The name of the vaccine for this is Hib vaccine
2. Hepatitis B vaccine - is a vaccine that prevents hepatitis B. The first dose is recommended within 24 hours of birth with either two or three more doses given afterwards.
3. Measles vaccine - measles is a highly contagious disease. It usually results to high fever and rashes and can lead to blindness, encephalitis or death.
4. 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.
5. Meningitis A is an infection that can cause severe brain damage and is often deadly.
6. 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.
7. Pneumococcal diseases include pneumonia, meningitis and febrile bacteraemia, as well as otitis media, sinusitis and bronchitis.
8. Polio is a highly infectious viral disease that can cause irreversible paralysis. In 2017, 85 per cent 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. Nigeria is also witnessing vaccine derived polio due to the non-compliance with immunization schedule by parents.
9. Rotaviruses are the most common cause of severe diarrhoeal disease in young children throughout the world.
10. 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.
11. 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 tetanus vaccine to prevent maternal and neonatal tetanus had been introduced in Nigeria. Maternal and neonatal tetanus persist as public health problems in 14 countries, mainly in Africa and Asia.
12.. Yellow fever is an acute viral haemorrhagic disease transmitted by infected mosquitoes.