Immunization coverage

Immunization coverage

Stark inequalities in access to vaccination exist within and between countries, with children living in disadvantaged circumstances having considerably lower uptake. The reasons for these inequalities are complex but ultimately they reduce population immunization coverage, prevent achievement of herd immunity, and increase the chance of continuing or re-emerging epidemics of infectious disease. Another major threat to immunization coverage is an unfounded lack of professional and parental confidence in the safety and effectiveness of immunization.

In industrialized countriesthis usually reflects exaggerated or erroneous fears of adverse reactions, often following media scares. In developing countries this can reflect false beliefs about infectious disease and immunization. Problems in maintaining an adequate supply of vaccine and new developments leading to frequent changes to immunization schedules also impede high coverage.
Developing and delivering an effective vaccination policy is challenging for any country. Issues to consider include having comprehensive documented policies/guidelines, clear lines of responsibility, ensuring an adequate and safe vaccine supply chain, ensuring professionals.

delivering vaccination are adequately trained and supported, and fostering confidence in and engagement with the immunization program.

Immunization coverage

Many of these issues have been clearly set out by the World Health organization in Immunization in Practice: A Practical Resource Guide for Health Workers.
Interventions to increase vaccination coverage can be patient,
provider, or system orientated. Examples of interventions of proven effectiveness include:
* robust patient call–recall and reminder systems;
* provider prompt systems (for example computer ‘pop-ups’ that flag when a child attending any health care setting is overdue vaccinations);
* multifaceted education programs for professionals and parents;
* generally increasing the accessibility of immunization (including providing accessible immunization clinics and making immunization available in other settings such as hospital outpatients and Accident and Emergency departments);
* ensuring vaccination providers receive regular assessment of and feedback on their performance relative to vaccination targets;
* integrating immunization into general mother and child health programs;
* ensuring parents and providers do not incur costs associated with vaccination.

Making complete vaccination a requirement for children to enter childcare or school is effective in increasing coverage and is used in some countries. This approach has not been adopted in the UK due to the potentially damaging consequences of overriding parental choice. Ensuring the availability of high-quality information on the target population population that would benefit from vaccination is also important in developing effective recall systems and monitoring performance. Achieving and maintaining high vaccination coverage is an important effective measure to reduce health inequalities.

Source: Forfar and Arneil’s Textbook of Pediatrics, 7E


Prevention in neonatal period

Prevention in neonatal period

Good intrapartum obstetric care and subsequent effective monitoring, investigation and treatment of the many disorders from which the newborn infant may suffer are important preventive measures. Such disorders include asphyxia, birth injury, low birth weight and hyperbilirubinemia. Neonatal screening procedures are discussed in the section
on Child health surveillance and screening.

The promotion of breast-feeding is a crucial preventive measure. Breast-feeding reduces the risk of necrotizing enterocolitis, diarrheal disease, lower respiratory infections, otitis media, and other serious neonatal infections. It also appears to reduce the risk of childhood obesity, probably through better development of appetite control. Recent evidence has further linked lack of breast-feeding with poorer intellectual development, possibly due to the lack of certain long chain fatty acids, essential for normal brain development, in most breast milk substitutes, although it is difficult to totally exclude the possibility of confounding from these studies.

Frequent breast-feeds given over a prolonged period also significantly reduce fertility and increase the birth interval, with indirect benefits to both mother and infant. WHO and UNICEF are coordinating a global initiative (the Baby Friendly Hospital Initiative) to promote breast-feeding and to improve health service support for breast-feeding mothers. Hospital routines and practices can discourage women from breast-feeding or make it difficult for them to do so successfully hence good practice guidelines have been developed for maternity hospitals. Key features of good practice include ‘rooming in’, i.e. allowing mother and babies to remain together, supporting skin-to-skin contact and the first breast-feed soon after birth, encouraging subsequent feeding on demand, and education of staff and mothers to promote good positioning and attachment of the baby.

Improving hospital practices and staff skills in line with these guidelines has been shown to improve breast-feeding rates across all ethnic and socio-economic groups. Policy statements on breast-feeding by pediatric associations have been used to raise awareness amongst pediatric staff of the need to promote breast-feeding, to promote good practice and to advocate for inclusion of breast-feeding topics in the undergraduate medical and nursing curricula and in postgraduate courses for pediatricians, obstetricians, general practitioners, midwives and maternal and child health nurses.

Prevention in neonatal period

Vitamin K should be given to all babies at birth to prevent the rare but serious disorder hemorrhagic disease of the newborn (HDN). Vitamin K administered either as one intramuscular injection shortly after birth or as multiple oral doses (with more doses required for breast-fed babies) over the first few weeks of life is effective at preventing early, classic, and late HDN. As compliance is higher and costs are lower with the IM route, that is the regimen that is usually preferred. This was questioned following the publication of one case–control study in 1992 that reported an association between administration of vitamin K via the intramuscular route to neonates and the subsequent development of childhood leukemia. Later studies and systematic reviews have failed to replicate this finding however, and the consensus view is now that IM vitamin K does not increase the risk of cancer. Current advice from the Department of Health for England states that all babies should be offered vitamin K but does not state which regimen should be followed.
The risks of HIV transmission are now better understood, leading to guidelines for the management of HIV-positive mothers to reduce vertical transmission of infection. Key interventions include universal antenatal screening of mothers for HIV infection, antiretroviral therapy for those found to be infected along with elective Cesarian section delivery and avoidance of breast-feeding in areas where it is safe to do so.

Source: Forfar and Arneil’s Textbook of Pediatrics, 7E