INTRODUCTION

Vaccination is the process of administering a vaccine, in order to help the immune system develop protection from a disease. Vaccines contain weakened versions of microorganisms and viruses and when administered, helps in stimulating the body’s immunity towards sickness from infectious diseases (ChangY, 2009). It is thereby the most effective method of preventing infectious diseases.

Vaccines protect the body throughout life and at different ages, from birth to childhood, as teenagers and into old age. According to the Nigerian Federal Ministry of Health, a child is regarded as fully vaccinated only when he/she has received a BCG vaccination against tuberculosis; three doses of DPT to prevent diphtheria, pertussis (whooping cough), and tetanus; at least three doses of polio vaccine; and one dose of measles vaccine all within their first year of life over the course of five visits, including the doses delivered at birth (Tula et al., 2014). In accordance with this schedule, children aged 12–23 months would have concluded their immunizations and be fully immunised. To track and monitor the delivery of these vaccines and when next they are due, all parents or guardians are provided with a health card on which each dose is recorded.

It is important to make sure that all these vaccines are up to date and taken at their appropriate times, if there is a delay, the body is put at risk of getting seriously sick. The wait period where a disease outbreak will be the motivating factor to get a vaccine is not advisable, there may not be enough time for the vaccine to work and to receive all the recommended doses. Increases in vaccine coverage have therefore been seen as an important strategy for reducing infant and child mortality rates.

Vaccines help in the prevention of 2–3 million deaths each year (WHO, 2018). A high proportion of vaccine-preventable deaths occur in early infancy (WHO,2015). While some deaths cannot be directly prevented because of the minimum age of vaccination, delay in vaccination from schedule can result in preventable deaths. Numerous studies have documented delays in vaccination in multiple settings (Clark A.,Sanderson C., 2009).

GLOBAL STATISTICS

Globally, an estimated 25% of under-five deaths were attributed to vaccine preventable diseases (VPDs) in 2017 (UN-IGME, 2017). Despite all the efforts to introduce and encourage essential vaccine uptake, VPDs still account for over half a million under five deaths annually in Africa, representing 56% of global VPD-related deaths (WHO, 2019). Between 1990 and 2017, immunization contributed to a 55% global decline in under-five mortality rates, with a drop from 87 to 39 deaths per 1,000 live births, and from 2011 to 2020, over 14 million deaths were prevented by measles vaccination alone (BMGF, 2008).

Nigeria ranks second to India with the highest number of neonatal deaths (UNICEF, 2013) and as such, there is the need for continuous attention and interventions to help reduce the risk of mortality among neonates. Some of the factors attributed to this include misconception about immunization and the rejection of routine immunization (Ophori, 2014). Vaccinations also have to be taken at the stipulated time and in the correct order for them to be effective. Infectious diseases have always been one of the major causes of child deaths, but the success of vaccination campaigns and antibiotic availability has done a great deal to reduce mortality from infectious diseases (CDC, 2020).

LOCAL STATISTICS

Figure 1: Percentage of children (aged 1) fully immunized in Nigeria over the years, NHMIS 2013-2020. (Source: The MSDAT)

According to the National Health Management Information System (NHMIS), an estimated 60% of children were fully immunized showing a 40% increase in the percentage of children fully immunized since 2013 (Fig. 1). The rate of immunization has been on an increase since 2013 up until 2018, 2020. In 2014, the increase started with about 28% increase from 2013 and maintained an increase till 2020.

Figure 2: Percentage of children aged 1 fully immunized across Nigeria, NHMIS 2013-2020. (Source: The MSDAT)

According to the National Health Management Information System (NHMIS), the chart shows the percentages of children fully immunized at the age of 1 across the 36 states in Nigeria. The national target percentage is 85%. The states that met the target and have percentages beyond the national target are Jigawa, Adamawa and Kaduna, having a percentage of about 5% above the national target.The state with the lowest target percentage was Bayelsa having a percentage of about 18% of children fully immunized at the age of one.

Figure 3: Percentage of children fully immunized against childhood diseases by age 1 according to geopolitical zones NHMIS 2013-2020. (Source: The MSDAT)

According to the National Health Management Information System (NHMIS), the chart shows the percentages of children fully immunized at the age of 1 across the regions in Nigeria. The national target percentage is 85%. The regions that met the target and have percentages beyond the national target are the North-west and the North-east. The regions that had the lowest percentages are the South-south and South-east.There is a 70% difference between the lowest region having the lowest percentage and the region with the highest percentage which are Edo and Jigawa respectively.

FACTORS ASSOCIATED WITH DELAYED VACCINATIONS

1. Delayed vaccination increases the susceptibility window for vaccine preventable diseases. There are factors associated with delayed vaccination, some of them are outlined below; 

2. Maternal factor: Early childbirth and lower maternal education was associated with delay of vaccination. The mother of the child, going through childbirth at an early age as an adolescent will mean being out of school where being educated about immunization would have been missed can lead to delayed vaccination as knowledge on the right medical procedures post childbirth is not known by the mother.

3. Birth weight: Low birth weight, especially those below 2 kg at birth and pre-maturity are known to be associated with vaccination delay, because of the parental concern about the safety and benefit of vaccination for a premature child. This is because the parents of the child are already concerned that the child is a premature born, so taking the vaccination against disease when they aren’t sure of life isn’t something they are necessarily open to vaccination at that point.

4. Education: Understanding of the importance of vaccination. Some people do not have the education about vaccination and its importance. Hence will have their offspring in the delayed vaccination bracket. Out of fear, because of lack of proper education some parents or guardians refuse the vaccination.

5. Health care services: Out-of-hospital birth, individuals that do not give birth in the hospital means they didn’t get to attend the prenatal classes and get the education on vital subjects such as vaccination, these set of individuals will most likely have the vaccination of their child delayed mainly because they are unaware of what to do. Also out of hospital birth leads to irregular monitoring or no monitoring, as the hospitals wouldn’t have the bio-data of the child being born to monitor the vaccination schedules and appointments.

IMPACT OF COVID-19 ON VACCINATION 

Figure 3: Immunization-Fully immunized less than one year  NDHS, 2018 (Source: The MSDAT)

The image above depicts the indicator of babies immunized less than a year at the National level. In 2019, a total of 492,786 babies were immunized in February , in 2020, there was drop in the number leading to a total of 443,743 babies immunized in february, in 2021, there was a massive drop in the total amount of babies immunized leading to a total of 384,659. Reduction in routine immunization rates exposes children to vaccine preventable diseases. 

During the COVID-19 pandemic, access to routine healthcare for regular needs, such as antenatal care, newborn screening, or immunization was limited (UNICEF, 2020). There is a probability that Nigerian citizens might also have been afraid to attend healthcare services due to fear of contracting the virus (WHO, 2020). 

LIST OF VACCINE PREVENTABLE DISEASES

1. Polio: Polio is a crippling and potentially deadly infectious disease that is caused by polio virus. The virus spreads from person to person and can invade an infected person’s brain and spinal cord, causing paralysis. It is recommended that your child get four doses of the polio vaccine (also called IPV). Children need one dose at each of the following ages:1-2 months and 4 months.

2. Tetanus: This causes painful muscle stiffness and lockjaw and can be fatal. It is recommended that your child get five doses of the DTaP vaccine. Children need one dose at each of the following ages:1-2 months and 4 months.

3. Hepatitis B: This is spread through blood or other bodily fluids. It’s especially dangerous for babies, since the hepatitis B virus can spread from an infected mother to child during birth. About nine out of every 10 infants who contract it from their mothers become chronically infected, which is why babies should get the first dose of the hepatitis B vaccine shortly after birth. All pregnant women should be tested and all babies should be vaccinated.

It is recommended that children get three doses of the Hepatitis B shot for best protection. Typically, infants will need one dose at each of the following ages, shortly after birth, 1-2 months and 6 months.

4. Hib (Haemophilus influenzae type b): Hib can do some serious damage to a child’s immune systems and cause brain damage, hearing loss, or even death. Hib mostly affects kids under five years old. It is recommended that a child gets four doses of the Hib vaccine. Children will need one dose at each of the following ages: 1-2 months, 4 months.

5. Whooping cough, or pertussis: This is a highly contagious disease that can be deadly for babies. Whooping cough can cause uncontrollable, violent coughing, which often makes it hard to breathe. Its “whooping” name comes from the sharp breath intake sound right after a coughing fit. In babies, this disease also can cause life-threatening pauses in breathing with no cough at all. Whooping cough is especially dangerous to babies who are too young to be vaccinated themselves. Mothers should get the whooping cough vaccine during each pregnancy to pass some protection to their babies before birth. It is very important for babies to get the whooping cough vaccine on time so they can start building their own protection against the disease.

It is recommended that children get five doses of the DTaP vaccine. A child will need one dose at each of the following ages:1-2 months, 4 months, 6 months

6. Pneumococcal Disease: This disease is caused by bacteria called Streptococcus pneumoniae. It causes ear infections, sinus infections, pneumonia, and even meningitis, making it very dangerous for children. The germs can invade parts of the body—like the brain or spinal cord—that are normally free from germs.

It is recommended that a child gets four doses of the pneumococcal conjugate vaccine (also called PCV13). One dose at each of the following ages: 1-2 months, 4 months.

7. Rotavirus: This is contagious and can cause severe watery diarrhea, often with vomiting, fever, and abdominal pain, mostly in infants and young children. Children can become severely dehydrated from the disease and need to be hospitalized. If a dehydrated child does not get needed care, they could die. Rotavirus is one of the first vaccines an infant can get; it’s the best way to protect your child from rotavirus disease. It is recommended that children get two or three doses of the vaccine (depending on the brand) at 1-2 months, 4 months.

8. Diphtheria: This vaccine, called DTaP, provides protection against diphtheria, tetanus, and pertussis (whooping cough). While preventable, diphtheria does still exist. It can cause a thick covering in the back of the nose or throat that makes it hard to breathe or swallow. Diphtheria can also lead to heart failure, paralysis, and even death. Make sure to vaccinate to help keep this dangerous infection from your kids.

It is recommended that a child gets five doses of the DTaP vaccine. A child will need one dose at each of the following ages: 1-2 months, 4 months.

RECOMMENDATION AND CONCLUSION

Protection from vaccine-preventable diseases is a child’s basic right and while a lot of work has been put into the creation of vaccines to help reduce neonatal mortality rate, the accomplishments are still limited because of non-compliance to the routines and schedules of when vaccines are to be taken and completion of required doses. To help with these, the following can be done;

1. The creation of an outreach system to follow up children who miss doses.

2. Entry checks and sensitization at schools to promote immunisation. 

3. A national immunisation coverage surveillance system to enable implementation and evaluation of the other recommended strategies.  

4. An increase in resourcing health professional commitment is vital for success (Turner et al., 2000).

In addition, neonates are particularly vulnerable to infections with Gram-negative bacteria and group B Streptococcus, for which no neonatal vaccines currently exist (Kobayashi, M. et al,2016). The gap in early protection can be bridged by administering vaccines to women in pregnancy, relying on passively transferred antibodies to protect infants in the first few months of life, until vaccinations administered during infant stage or later can provide protection. On the basis of this principle, tetanus, influenza and pertussis vaccinations are recommended for pregnant women to prevent neonatal infections such as neonatal tetanus (Yen, 2019).

CITATIONS

Centers for Disease Control and Prevention. (2013)” Vaccines for your children” .LINK

National institute of child health and human development “Why are immunizations important for my infant “ LINK

Ophori, E. A., Tula, M. Y., Azih, A. V., Okojie, R., & Ikpo, P. E. (2014). Current trends of immunization in Nigeria: prospect and challenges. Tropical medicine and health, 42(2), 67–75. https://doi.org/10.2149/tmh.2013-13

United Nations Inter-agency Group for Child Mortality Estimation (UN IGME) United Nations Children’s Fund; New York: 2017. Levels & Trends in Child Mortality: Report 2017. Estimates Developed by the UN Inter-agency Group for Child Mortality Estimation.

Turner, Nikki & Baker, M. & Carr, J. & Mansoor, Osman. (2000). Improving immunisation coverage: What needs to be done?. New Zealand Public Health Report. 7. 11-14. 

World Health Organization “ Vaccination and children” LINK

Feikin DR , Flannery B, Hamel MJet al. “Vaccine preventable diseases in children”.

Clark A., Sanderson C 2009. “Timing of children’s vaccinations in 45 low-income and middle-income countries” 

World Health Organization  ”10 facts on immunization” LINK

Onayade AA, Sule SS, Elusiyan JB: “Determinants of neonatal mortality” 2006

UNICEF: “The state of the world’s children 2008.” LINK

Bill & Melinda Gates Foundation. “The Goalkeepers Report” (2018).LINK

Kobayashi, M. et al. “Group B Streptococcus vaccine development: present status and future considerations, with emphasis on perspectives for low and middle income countries(2016).” 

Madhi, S. A. & Dangor, Z.” Prospects for preventing infant invasive GBS disease through maternal vaccination(2017)”

Yen, L. M. & Thwaites, C. L. Tetanus. Lancet 393, 1657–1668 (2019).

Ophori EA, Tula YM, Azih A, Okojie R, Ikpo PE. Current Trends of Immunization in Nigeria: Prospect and Challenges. Tropical Medicine and Health. 2014;42(2):67–75.

UNICEF/WHO/World Bank/UN. Levels and Trends in Child Mortality. USA; 2013.

Oestergaard M, Inoue M, Yoshida S, Mahanani W, Gore F, Cousens S, et al. Neonatal Mortality Levels for 193 Countries in 2009 with Trends since 1990: A Systematic Analysis of Progress, Projections, and Priorities

Herd immunity (Herd protection) | Vaccine Knowledge”. vk.ovg.ox.ac.uk. 12 November 2020.

 Fiore AE, Bridges CB, Cox NJ (2009). Seasonal influenza vaccines. Current Topics in Microbiology and Immunology. 333. pp. 43–82. 

Chang Y, Brewer NT, Rinas AC, Schmitt K, Smith JS (July 2009). “Evaluating the impact of human papillomavirus vaccines”. Vaccine. 27 (32): 4355–62.

Danis K., Georgakopoulou T., Stavrou T., Laggas D., Panagiotopoulos T. Socioeconomic factors play a more important role in childhood vaccination coverage than parental perceptions: a cross-sectional study in Greece. Vaccine.

World Health Organization and United Nations Children’s Fund. Global Immunization Vision and Strategy, 2006–2015. Geneva, Switzerland: World Health Organization and United Nations Children’s Fund; 2005. Available at http://www.who.int/vaccines/GIVS/english/GIVS_Final_17Oct05.pdf