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Availability And Storage Of Vaccines In Community Pharmacies
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CHAPTER ONE
INTRODUCTION
1.0 Background of the Study
Immunization is the process by which an individual’s immune system becomes fortified against an agent (known as the immunogen). When this system is exposed to molecules that are foreign to the body, called non-self, it will orchestrate an immune response, and it will also develop the ability to quickly respond to a subsequent encounter because of immunological memory. This is a function of the adaptive immune system. Therefore, by exposing an animal to an immunogen in a controlled way, its body can learn to protect itself; this is called active immunization (Okwor, et al., 2012)
The most important elements of the immune system that are improved by immunization are the T cells, B cells, and the antibodies B cells produce. Memory B cells and memory T cells are responsible for a swift response to a second encounter with a foreign molecule. Passive immunization is direct introduction of these elements into the body, instead of production of these elements by the body itself. Immunization is done through various techniques, most commonly vaccination. Vaccines against microorganisms that cause diseases can prepare the body’s immune system, thus helping to fight or prevent an infection. The fact that mutations can cause cancercells to produce proteins or other molecules that are known to the body forms the theoretical basis for therapeutic cancer vaccines. Other molecules can be used for immunization as well, for example in experimental vaccines against nicotine (NicVAX) or the hormone ghrelin in experiments to create an obesity vaccine. Immunizations are definitely less risky and an easier way to become immune to a particular disease by risking a milder form of the disease itself. They are important for both adults and children in that they can protect us from the many diseases out there.
Through the use of immunizations, some infections and diseases have almost completely been eradicated throughout the United States and the World. One example is polio. Thanks to dedicated health care professionals and the parents of children who vaccinated on schedule, polio has been eliminated in the U.S. since 1979 (American Pharmaceutical Association [Apha] , 2013). Polio is still found in other parts of the world so certain people could still be at risk of getting it. This includes those people who have never had the vaccine, those who didn’t receive all doses of the vaccine, or those traveling to areas of the world where polio is still prevalent.
Immunization is the most precious gift that a health care worker can give a child and it remains the most cost effective preventative health intervention presently known (South Africa, 2003; Cameroun, 2009). Vaccines are sensitive biological substances that gradually lose their potency with time (World Health Organization [WHO] , 1998) and this loss of potency can be accelerated when stored out of the recommended range of temperature (WHO, 2004). Any loss of potency in a vaccine is permanent and irreversible. Consequently, a proper storage of vaccines at the recommended temperature conditions is vital so that vaccines’ potency is retained up to the moment of administration (WHO, 1998).
Before the development and wide use of human vaccines, few people survived childhood without experiencing a litany of diseases including measles, mumps, rubella, chickenpox, whooping cough, and rotavirus diarrhea. In addition to these universal diseases of childhood, thousands of children each year suffered or succumbed to life threatening episodes of paralytic poliomyelitis, diphtheria, or bacterial meningitis caused by Haemophilus influenza type b (Hib) or Streptococcus pneumonia (Sutter, et al., 1999).
Vaccines are considered to be one of the most cost-effective preventive measures against certain diseases, and the Centers for Disease Control and Prevention (CDC) declared vaccinations to be one of the top 10 public health achievements of the 20th century (WHO, 1998), vaccinations have saved millions of lives since their introduction more than 200 years ago (WHO, 2004).
Community pharmacists are uniquely placed to provide support and advice to the general public compared with other health care professionals. The combination of location and accessibility means that most consumers have ready access to a pharmacy where health professional advice is available on demand (Bradshaw et al., 1998). A high level of public trust and confidence in pharmacists’ ability to advice on non-prescription medicines is afforded to community pharmacists (Pharmacy Research UK., 2009). Although there is a general global move to liberalize non-prescription markets, pharmacies in many countries still are the main suppliers of non-prescription medicines (Tisman, 2010). Pharmacists are therefore in a position to facilitate consumer self-care and self-medication, which needs to be built on and exploited.
A recent survey of public health leaders (Rambhia, et al., 2009) identified pharmacists as playing a key role in vaccine administration and pandemic planning. Evidence in published medical literature suggests that pharmacies are uniquely positioned to influence previously difficult-to-reach populations (Crawford, et al., 2011; Westrick, 2010). A review of pharmacy-led immunization programs (Francis and Hinchliffe, 2011) concluded that pharmacies might be especially effective in immunizing high-risk, older adults who are more likely to need prescription medications and, therefore, use pharmacy services. Pharmacist interventions have been shown to improve medication adherence (Jiang, et al., 2010), provide increased access to health care expertise and advice, and perform a variety of primary care services (Taitel, et al., 2011).
Rutter, (2015) in his submission noted that the pharmacy has a long history of facilitating self-care, however, more than ever before, pharmacists and their staffs are being provided opportunities to expand their contributions which include involvement in routine immunization. Although considerable barriers still existif the community pharmacy is to maximize its potential there is urgent need to ask about pharmacists’ ability and readiness to embrace change especially as it relates to vaccine storage (Rutter, 2015).
1.1 Type of Vaccines
Vaccines are dead or inactivated organisms or purified products derived from them. There are several types of vaccines in use (National Institute of Allergy and Infectious Disease, 2012). These represent different strategies used to try to reduce risk of illness, while retaining the ability to induce a beneficial immune response.
Inactivated Vaccines
Some vaccines contain inactivated, but previously virulent, micro-organisms that have been destroyed with chemicals, heat, radiation, or antibiotics. Examples are influenza, cholera, bubonic plague, polio, hepatitis A, and rabies vaccines.
Attenuated Vaccines
Some vaccines contain live, attenuated microorganisms. Many of these are active viruses that have been cultivated under conditions that disable their virulent properties, or that use closely related but less dangerous organisms to produce a broad immune response. Although most attenuated vaccines are viral, some are bacterial in nature. Examples include the viral diseases yellow fever, measles, rubella, and mumps, and the bacterial disease typhoid. The live Mycobacterium tuberculosis vaccine developed by Calmette and Guérin is not made of a contagious strain, but contains a virulently modified strain called “BCG†used to elicit an immune response to the vaccine. The live attenuated vaccine-containing the strain Yersinia pestis EV is used for plague immunization. Attenuated vaccines have some advantages and disadvantages. They typically provoke more durable immunological responses and are the preferred type for healthy adults. But they may not be safe for use in immunocompromised individuals, and may rarely mutate to a virulent form and cause disease
Toxoid
Toxoid vaccines are made from inactivated toxic compounds that cause illness rather than the micro-organism. Examples of toxoid-based vaccines include tetanus and diphtheria. Toxoid vaccines are known for their efficacy. Not all toxoids are for micro-organisms; for example, Crotalus atrox toxoid is used to vaccinate dogs against rattlesnake bites.
Subunit Vaccines
Protein subunitrather than introducing an inactivated or attenuated micro-organism to an immune system (which would constitute a “whole-agent†vaccine), a fragment of it can create an immune response. Examples include the subunit vaccine against Hepatitis B virus that is composed of only the surface proteins of the virus (previously extracted from the blood serum of chronically infected patients, but now produced by recombination of the viral genes into yeast), the virus-like particle (VLP) vaccine against human papillomavirus (HPV) that is composed of the viral major capsid protein, and the hemagglutinin and neuraminidase subunits of the influenza virus. Subunit vaccine is being used for plague immunization.
CHAPTER ONE -- [Total Page(s) 7]
Page 1 of 7
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