CHAPTER ONE

INTRODUCTION

Background to the Study

A vaccine is a biological preparation that provides active acquired immunity to a particular disease. A vaccine typically contains an agent that resembles a disease-causing microorganism and is often made from weakened or killed forms of the microbe, its toxins, or one of its surface proteins. The agent stimulates the body’s immune system to recognize the agent as a threat, destroy it, and keep a record of it, so that the immune system can easily recognize and destroy any of these microorganisms that it later encounters (Kids Health, 1995-2015).

Vaccines can be prophylactic (i.e. prevent or ameliorate the effects of a future infection by any natural or “wild” pathogen), or therapeutic (i.e. the use of drugs in the cure of disease). The administration of vaccines is called vaccination. Vaccination is the most effective method of preventing infectious diseases (United States Center for Disease Control and Prevention, 2011). The global effort to use vaccination as a public health intervention began when the World Health organization (WHO) launched the Expanded Programme on Immunization (EPI) in 1974. Nigeria as one of the member states, adopted EPI and it began operations in 1980 and was officially re-launched in 1984 with huge success in terms of vaccination coverage. In 1990 BCG coverage recorded 80%, DPT 56%, Polio 55% and Measles 54% (Obioha, Ajala, Matobo, 2010).

However, the purpose of EPI was simple and straight-forward; to deliver multiple vaccines to all children through a simple schedule of child health visits (Chan, 2014). At the time, basic health systems in most low and lower middle income countries (LLMICs) were weak to nonexistent. Vaccine coverage levels among children younger than 1 year of age were less than 5% (Chan, 2014). By 1990, most LLMICs had institutionalized immunization programs based on the EPI blueprint. In 1991, the global target of vaccinating 80% of the world’s children was declared to have been met, saving millions of lives (Chan, 2014). Since then, more vaccines have been added to national immunization schedules, and the contribution of immunization programs to

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ongoing declines in infant and child mortality has increased commensurately (Ozawa, Stack, Bishai, Mirelannin, Friberg, Niessen, 2011; Decade of Vaccine, 2014). As of 2014, WHO has recommended that all immunization programmes add vaccines against hepatitis B, Haemophilusinfluenzae type b (Hib), streptococcus pneumoniae, rotavirus, rubella, and human papillomavirus (in girls). WHO estimates 29% of deaths among children 1 – 59 months of age are vaccine preventable (World Health Organization, 2014). This gap is due to systems weaknesses in immunization programs that can be improved. With the addition of new vaccines, the complexity and costs of routine immunization increased (WHO 2013; Chan 2014; DOV 2014; United Nations Children’s Fund, 2014). Fulfilling the vision of EPI requires sustained investments in routine immunization (Steinglass, 2013). Additionally, the economic benefits of immunization are significant. Healthier individuals are, in the long term, more productive contributors to a country’s wealth, particularly as countries rapidly transition from high to lower mortality levels (Bloom, 2011).

Immunization is one the most cost effective public health interventions to date, saving millions of lives and protecting countless children from illness and disability (Levine, 2011). As a direct result of immunization, polio is on the verge of eradication. Deaths from measles, a major child killer, declined by 71% worldwide and 80% in sub-Sahara Africa between 2000 and 2011 (Robert, 2012). Since most vaccines are sensitive to heat, an adequate cold-chain system often has to preserve the quality of a vaccine before it is administered (WHO, 2011). Although emphasis has long been placed on avoiding high temperatures during vaccine storage and shipment, World Health Organization (WHO) recommends that all childhood vaccines except the oral polio vaccine be kept at 2 – 8oc during their in-country distribution (Ministry of Health & Family Welfare, 2010). Without proper operation, maintenance, and monitoring of each phase of vaccine cold chain in the distribution, vaccines are put at risk. Therefore, maintenance of cold chain system is vital as any error during the storage/transportation results in vaccine failure, which in turn has negative effect on vaccine potency, immunization coverage rate, reporting of disease despites the availability and administration of vaccines, use in adverse events following immunization among vaccinated children, loss of faith of general population on public health system, and

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significant burden on the existing health infrastructure (Mallik, Mandal, Chatterjee, Ghosh, Manna, Chakraharty, 2011).

Barber (2012) found that cold chain failures are the most significant contributors to vaccine storage waste. He further stated that the cold chain breaks for several reasons but in 90% of cases, it is due to human error. A report presented by the office of the Inspector General for the Vaccine for Children Program (VFC), published in June 2012, also found that 76% of providers (clinics and offices) exposed their vaccine to inappropriate temperatures for 130 hours per year, costing approximately $368,820 per location wastage.

A recent study in United States found a high number of accidental exposures to freezing temperatures for vaccine vials labeled for storage at 2 – 80c due to inappropriate shipping or interim storage at health centers (Angoff, Wood, Chernock, 2013). Unintended freezing of aluminum adjuvanted vaccines during transportation and distribution in the vaccine cold chain has become a concern in the developing world as well, since many WHO prequalified vaccines are freezing sensitive (Turner, Laws, Roberts, 2011). Even under well controlled storage conditions, the temperature can vary throughout a refrigerator placing vaccine supplies at risk of freezing during storage (Rogers, Dennison, Adepoju, Dowd, Udoei, 2010).

Each year, vaccination averts between two to three million deaths, across all age groups, from diphtheria, tetanus, pertussis and measles (UNICEF, 2014). However, vaccine-preventable diseases are still responsible for about 25% of the 10million deaths occurring annually among children under five years of age (Global Immunization Vision and Strategy, 2006 – 2015). Nearly 80% of under five deaths occur in sub-Sahara Africa and about half of the deaths, in one of five countries: India, Nigeria, Democratic Republic of the Congo, Pakistan, and China (Black and Robert, 2010). For example, in 2005, Nigeria accounted for 41% of the global wild poliovirus case. The total number of confirmed wild poliovirus cases for the year 2005 was 801 with a total of 21 states infected (Global Polio Eradication Initiative, 2011). While in 2011, the total number of cases was 52 in number (Epstein, Tewarik, Lyke, Sim, Billingsley, Laurens, 2011).

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The maintenance of the cold chain at all levels of vaccine storage and distribution is obviously an essential and critical part of immunization programmes. When vaccines fall outside of specified temperature ranges by World Health Organization, they lose some or all of their effectiveness. Heat, freezing, even exposure to excessive humidity of vaccines can cause the potency to be limited or even be rendered useless. Therefore, the aim of this study is to assess the barriers to maintenance of cold chain for BCG and Measles vaccines among primary health care workers in Enugu metropolis.

Statement of the Problem

Vaccines are temperature sensitive biological products, so any exposure to extreme of temperature along the cold chain path is likely to reduce the potency. The World Health Organization recommends that all childhood vaccines except the oral polio vaccine be kept at 2 – 80C during their in-country distribution (MOHFW, 2010). Therefore, the cold chain must be monitored continuously in order to guarantee vaccine’s quality otherwise the potency will be compromised.

Unfortunately many health centres in developing countries including Nigeria and Enugu State in particular seem to lack functional cold chain equipment. This necessitates going to other health facilities that have the equipment with the attendant problems (Qian, Hongyan, Yafei, Rufu, Caizhongz, 2009). This upward and downward movement with the vaccines predisposes them to overheating and long term exposure to light which can damage the vaccines and pose serious problem to the success of expanded programme on immunization (Ministry of Public Health Cameroon, 2009). This situation is a source of doubt about the immunization of vaccinated children. This can explain a situation observed in Cameroon in which more than half of people with measles were reported to have been vaccinated against it (MPHC, 2009).

The primary cause of vaccine failure often occurs when pharmaceutical storage temperatures reach levels of degradation during the cold chain process (Military Vaccine, 2013). Yet vaccine loss is preventable (MILVAX, 2013), and vaccine-preventable diseases are still responsible for about 25% of the 10million deaths occurring annually among children under five years of age (GIVS, 2006 – 2015).

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It was reported that 14784 measles outbreaks occurred in Somalia, primarily from the South and Central Zones, in the Democratic Republic of the Congo, the outbreak was 103,000 cases, while in Nigeria, it was 17,428 cases (CDCP, 2011) despite the efforts so far made.

With reference to Tuberculosis, over 95% of TB deaths occur in low and middle-income countries, including Nigeria and it is among the top 5 causes of death for women aged 15 to 44 (WHO, 2014). According to global Tuberculosis report published by the WHO (2013), Nigeria is one of the six countries having the largest incidence of TB cases (WHO, 2014).

In Enugu State vaccine preventable diseases with particular reference to measles and tuberculosis showed that measles outbreaks were 222 in 2012, 266 in 2013, and 110 in 2014 while tuberculosis cases were 815 in 2012, 879 in 2013, and 651 in 2014. The report noted that majority of these patients were said to have been vaccinated against these diseases (Enugu State Ministry of Health, 2012-2014).

From the above reported cases, it is obvious that vaccine preventable diseases are reoccurring in both developing and developed countries including Enugu State. Documented evidence show that such outbreaks result mostly from cold chain failures (i.e. improper storage and handling of vaccines) (California Department of Public Health, 2009; Barber, 2012; MILVAX, 2013; Hartford HealthCare Medical Group, 2014; Yakum, Ateudjieu, Walter and Watcho, 2015). It is on this background that the researcher deems it necessary to assess those barriers to maintenance of cold chain for BCG and Measles vaccines among primary health care workers in Enugu metropolis.

Purpose of the Study

The purpose of the study is to assess barriers to maintenance of cold chain for BCG & Measles vaccines among health care workers in health centres in Enugu metropolis.

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