OVERVIEW OF HEALTHY LEIVING

DEFINITION OF HEALTH

Bircher defines health as a dynamic state of well-being characterized by a physical and mental potential, which satisfies the demands of life relative to age, culture and personal responsibility. Saracchi defines health as a state of well-being, free of disease or infirmity, and a basic and universal human right. The world health organization defines health as a complete state of complete physical , mental and social well-being, and not merely the absence of disease or infirmity.

Determinants of health

Lifestyle or the practices of the individual. According to the WHO, the main determinants of health are the social and economic environment, the physical environment, and the person’s individual characteristics and behaviours. To a large extent, factors such as the place where individuals live, the state of the physical environment, genetics, income and education levels, and the individual’s relationships with friends and family all have considerable impacts on health.

Role of behaviours in health

Behaviour simply refers to what people do or what people fail to do in relation to their health. The overall health of individuals is impacted by behaviours including healthy diets, physical activity, smoking and alcohol consumption.

How to stay healthy in the campus

· Eat well

· Rest well: insufficient sleep is associated with a number of dieseases and conditions, such as diabetes, cardiovascular disease, obesity and depression.

· Exercise well

· Love safely and carefully

Other tips on staying healthy

· Take enough clean, fresh air

· Wash your hands

· Brush your teeth

· Use seat belt

· Do not fight stress by eating

· Limit suagary and caffeinated beverages

· Limit junk food

· Seek help when you need it.

NUTRITION AND HUMAN HEALTH

Human nutrition and health

Nutrition refers to the science that studies the process in which living organisms take in and make use of food for the production of energy, the functioning of organs and tissues, maintenance of life, growth and reproduction, and elimination of waste products from the body.

What is food

Food is what we eat that provides the chemical components which nourish the body. Good food is wholesome, nourishing, and free from toxic substances, parasites and bacterial contamination.

Diet

Diet is what a person habitually eats; hence everyone is always on a diet. However, a special diet can be prescribed for an individual. For example, a diet to reduce weight, a diet to maintain normal weight, a diet to reduce a nutrient intake

Understating nutrients and their utilization

The chemical components of food are called nutrients: the nutrients are grouped into two: the macro and the micronutrients.

· The macronutrients are protein, fat and carbohydrate. They are required in larger amount than micronutrients. Protein provide amino acids for body building and repair of body tissues as well: fat provides energy and fat soluble vitamins.

· The micronutrients consist of vitamin and minerals. Vitamins are chemical compounds of organic nature that occur in minute quantities in food but are necessary for life and growth. It is often said that valuable things come in small package. Many are components of enzymes and thus facilitate the use of energy giving nutrients and are important regulators of the syntheses of countless body compounds. Minerals are inorganic substances as a contrast to organic compounds such as proteins, fat, carbohydrates and vitamins. They are found in all body tissues and fluids. Unlike vitamins, they are not destroyed in food preparation but can dissolve in water and loss will occur if cooking liquids are discarded.

The nutrients

The chemical substances in food which provide the body with energy, enables it to grow and to function properly are called nutrients. Most foods contain more than one nutrient. There are six major classes of nutrients: carbohydrates, fats and oils(lipids), protein, vitamins and minerals.

Carbohydrates

Plants are the main source of all carbohydrates which they manufacture through a process known as photosynthesis. All carbohydrates contain chemical elements of carbon, hydrogen and oxygen, and the hydrogen and oxygen are present in the same proportion as found in water. There are two types of carbohydrates which can be used in the body as food: starches and sugars. Starches: are the most complex group of carbohydrates called polysaccharides. The other group of polysaccharides is cellulose and hemicelluloses. Starches can be broken down to their simpler form called sugars.

Sugars: may be grouped into simple or complex sugars. The simple sugar consists of one-unit sugar called the monosaccharide. The monosaccharide includes: glucose, fructose and galactose.

· Glucose: it is the form in which carbohydrates exists in the blood. Sources are fruits, vegetables, corn syrup and hydrolyses of maltose, dextrose and lactose.

· Fructose: is also called laevulose or fruit sugar. Sources: honey, fruit and vegetables, corn syrup also from hydrolysis of lactose.

· Galactose: milk sugar. Sources: obtained only from hydrolysis of lactose (consisting of glucose and galactose).

the complex sugars (double sugars)

these are known as disaccharides. They include:

· Sucrose: consisting of one molecule of glucose and another molecule of fructose. It is called cane, beet or maple sugar. It is the sugar mostly used all over the world for sweetening foods.

· Maltose: consisting of one molecule of glucose and another glucose molecule.

· Lactose: consists of one molecule of glucose and a molecule of galactose

Fuctions of carbohydrates

· Provides energy

· Spares proteins from being used for energy

· Required for complete oxidation of fates

· Starches and sugars give flavours and variety to the diet.

Regulation of blood glucose

The product of carbohydrate digestion is glucose, fructose and galactose. These sugars are absorbed from the intestine to the intestinal lumen where fructose and galactose are converted to glucose. Glucose is the form of sugar in the blood. It is carried by the portal circulation to the liver and it is also rapidly withdrawn by all the cells of the body tissues as a source of energy. In normal health, glucose in excess of the body’s need is converted and stored in the liver and the muscle tissues. E.g. glycogen and consequently as body fat which can be used later for energy. The withdrawn blood glucose is constantly replaced by the liver. The amount of glucose in the blood is primarily regulated by the hormone insulin which is produced by the pancreas. If insufficient insulin is produced, it results in excess sugar in the blood.

High carbohydrate intake contributes to high calorie intake which could exceed the individual’s calorie requirement.

Fibre

A high fibre in the diet helps to prevent constipation and other several gastro-intestinal disorders.

Lipids

Fats and fatlike substance are often referred to as lipids which generally consist of compounds that are insoluble in water but soluble in organic solvents such as alcohol, ether, chloroform or benzene. Lipids can be classified into three broad groups as follows.

· Simple lipids

· Compound lipids

· Derived lipids

Fatty acids

· Hydrogenation is the addition of hydrogen to the carbon atom of unsaturated fat to produce saturated and solid fat. For example, margarine is prepared from vegetable oils by hydrogenation

· Rancidity of fat: fats becomes rancid if they are exposed to air and light oxidation makes the fat to change in colour, taste and odour.

Excess fat is stored in the adipose tissue as energy reserve. Fat can be stored in unlimited quantity. This is why one becomes overweight and eventually obese when excess fat is stored in the body.

Fats are essential for maintaining constant body temperature by providing insulation under the skin fat.

sources of cholesterol

· High sources- egg yolk, liver, brain, kidney heart, shrimp

· Low sources- skin milk, cheese from skin milk.

Protein

Protein like carbohydrates and fats contain carbon hydrogen and oxygen. In addition, proteins contain about 16% nitrogen. Sulphur, phosphorous, iron and sometimes iodine are found in small amounts in proteins.

Protein-caloric malnutrition

There are 2 forms of protein caloric malnutrition.

· Kwashiorkor: the infant is given only high carbohydrate; obtains enough caloric but inadequate supply of protein.

· Marasmus: occurs in infants who are weaned very early and are fed with diet that are low in calories as well as protein.

Digestion of food.

Digestion of food begins in the mouth with the chewing of food and its mixing with saliva. Food passes through the oesophagus to the stomach by relaxation of the cardiac sphincter, food mixes with the gastric juice containing hydrochloric acid, through the pyloric sphincter into the duodenum. Most digestive activities take place in the mouth, stomach, and the upper part of the small intestine which includes the duodenum and the jejunum.

Digestibility

The ease and speed of digestion is called digestibility. Efficiency of digestion of carbohydrate is 98%, fat is 95% and protein is 92%. Fibber and seeds are not digested and thus reduce digestibility rate of absorption of foods. Digestibility of food is also greatly reduced in some gastrointestinal disorders such as diarrhoea.

Absorption

Absorption is the process whereby the nutrients released from food by digestion are transferred from the intestinal lumen into the blood and lymph circulation. Absorption of nutrients mostly takes place at the lower part of the jejunum and also at the ileum.

Excretion of waste products

Excretion of waste products is accomplished by the kidneys which remove nitrogenous waste, water, mineral salts and excess water-soluble vitamins.

Minerals

Minerals represent about 4% of body weight, and are needed by the body to build tissues, regulate body fluids, or assist in various body functions: and are found in all body tissues. The solution of minerals when dissolved in water forming anions and cations serve as electrolytes in the body.

Macro minerals

Calcium

Human body contains more calcium than any other minerals, and 99% of the calcium is contained in the skeleton and teeth, while the rest 1% is found in the blood. The best sources of calcium are milk and milk products which provide large quantities of calcium in small servings.

Deficiency of calcium can result in rickets (poorly formed bone structure in early childhood), causes bow legs, enlarge wrists or ankles, stunted growth etc.

Potassium

Potassium is an electrolyte found in the intracellular fluid. It is essential for fluid balance and osmosis. It is also necessary for transmitting nerve impulses and muscle contraction. It is found in many foods, especially fruits like melons, oranges bananas, etc. and vegetables such as mushrooms, tomatoes, lima beans, carrots, potatoes, Brussels sprouts.

Potassium deficiency can be caused by diarrhoea, vomiting, diabetic acidosis, severe malnutrition, or excessive use of laxatives. Symptoms of its deficiency include nausea, anorexia, fatigue, muscle weakness, and heart.

Sodium

Sodium is an electrolyte which dictions in the control fluid balance in the body, controls the extracellular fluid, and is essential for osmosis. It is important in maintaining acid base balance in the body, and participates in the transmission of nerve impulses essential for normal muscle function. Its primary source is the table salt but is naturally available in animal foods. Drinking water contains sodium but in varying amounts.

Magnesium

Magnesium is vital to both hard and soft body tissues. It is essential for metabolism and regulation of nerve and muscle function, including the heart, and plays a role in the blood clotting process. It is widely distributed in foods, but is primarily found in plant foods such as green leafy vegetables, legumes, nuts, whole grains, etc. deficiency includes nausea, mental, emotional, and muscular disorders.

Phosphorus

Phosphorus, together with calcium, is necessary for formation of strong bones and teeth. It is a constituent of all body cells which is important in the metabolism of carbohydrates, fates and proteins. Its source are protein rich foods such as milk, cheese, meats, poultry, and fish

Micro minerals

Iron

The principal role of iron is to deliver oxygen to the body. It is utilized by enzymes that are involved in the synthesis of amino acids, hormones and neurotransmitters. Its sources are meat, poultry, and fish. Vegetables and fruits.

Its deficiency results in anaemia, and can be caused by insufficient intake, malabsorption, lack of sufficient stomach acid, or excessive blood loss

Iodine

Iodine is a component of thyroid hormones. It is necessary for normal functioning of the thyroid gland. Its primary sources are iodized salt, sea foods, and some plants that are grown in soil bordering the sea.

Zinc

Zinc is a co-factor for enzymes, and is essential for growth, wound healing, taste acuity, glucose tolerance and mobilization of vitamin A in the body.

Its deficiency can cause decreased appetite and taste acuity, delayed growth, dwarfism, subnormal development of male sex organ, poor wound healing, anaemia and impaired immune response.

Copper

Copper is an essential component of several enzymes. It helps in the formation of haemoglobin, aids in transportation of iron to the bone marrow for formation of red blood cells, and participates in energy production. It is found in all tissues and organs such as muscles, liver, kidneys and brain.

Manganese

Manganese is a constituent of several enzymes involved in metabolism, and is important in bone formation. Its sources include whole grain and tea, vegetables and fruits.

Vitamins

They are required for control of metabolic reactions in the cells as well as for regulation of maintenance and growth of the body.

Classification of vitamins.

Vitamins are classified according to their solubility in water or fats and oils. Fat soluble vitamins are A, D, E and K. while water soluble ones are the b and vitamin c.

· Vitamin A. it is essential for maintaining healthy eyes and skin, needed for normal growth and reproduction, promote healthy immune system and aids in prevention of infections.

· Vitamin D. it contains large amount of calcium and phosphorus, is required for the proper formation of bones and teeth. Excess amount of vitamin D is stored in the liver and in adipose tissue. The best source of vitamin D is sunlight.

· Vitamin E. it is known as tocopherol is an antioxidant which protects polyunsaturated fatty acids from damage by free radicals, especially in cell membranes in the body. Sources of vitamin E include vegetable oils, soybean etc.

· Vitamin K, commonly called phyllo Quinone, is made up of several compounds that are essential to blood clotting. The best dietary sources of vitamin K are green leafy vegetables such as cabbage, spinach etc.

Water soluble vitamins

· Vitamin B: they are many and most often referred to as b complex.

· Vitamin C is found mainly in fresh fruits and vegetables such as citrus, strawberries, cabbage, spinach, green peppers, etc.

Water

Water is not often considered as a nutrient, like vitamins, minerals, proteins, fats or carbohydrates, and yet, water is essential for the human body.

· Water serves as the body’s transportation system

· Water is lubricant

· Water is present in the mucous and salivary juices or our digestive systems.

· Water participates in the body’s biochemical reactions.

· Water regulates body temperature

· Evaporation of water from body surfaces also helps to cool the body.

MICROBES AND HUMAN HEALTH

· A pathogen is an organism that bears suffering upon another organism. A true pathogen is an infectious agent that causes disease in virtually any susceptible host. An opportunistic pathogen is potentially infectious but rarely cause disease in individuals with healthy immune systems.

· An infection is the colonization of a host organism by parasite species. Infection begins when an organism successfully colonizes by entering the body, growing and multiplying. Disease results only if and when as a consequence of the invasion and growth of a pathogen, tissue function is impaired. Entrance to the host generally occurs through the mucosa in orifices like the oral cavity, nose, eyes, genitalia, anus or open wounds.

· Direct contact infections can result from inhalation of infectious organism found in aerosol particles emitted by sneezing or coughing. Others include, sex and hand to mouth.

· Indirect contact occurs when the organism is able to withstand the harsh environment outside the host for long periods of time and still remain infective when specific opportunity arises.

Pathogenic microbes

There are five major types of infectious agents: bacteria, viruses, fungi, protozoa and helminth.

· Bacteria are unicellular prokaryotic organism. Most bacteria reproduce by growing and dividing into two cells in a process known as binary fission. Bacteria can be classified into two broad classes based on their cell wall structures. Gram-negative bacteria appear pink under the light microscope, and gram positive bacteria appear purple after the gram staining procedure.

· Viruses. They are not complete living organisms themselves because, outside a host cell, they have no metabolism and cannot reproduce. A virus particle is composed of a viral genome of nucleic acid that is surrounded by a protein coat called a capsid. Viruses are classified using a variety of criteria including shape, size and type of genome.

· Fungi: fungi are eukaryotic, heterotrophic organisms that have rigid cellulose or chitin based cell walls and reproduce primarily by forming spores. Together with bacteria, fungi fulfil the indispensable role of decomposers in the environment

· Protozoa: they are unicellular, heterotrophic eukaryotes that include the ubiquitous amoeba and paramecium. Protozoa can be acquired through contaminated food or water or by the bite of an infected arthropod such as a mosquito.

· Helminths: they are simple, invertebrate animals, some of which are infectious parasites. They are multicellular and have differentiated tissues. Because they are animals, their physiology is similar in some ways to human. This makes parasitic helminth infections difficult to treat because drugs that kill helminths are frequently very toxic to human cells.

· Prions. During the past two decades, studies have shown that some degenerative disorders of the central nervous system are caused by infectious particles that consists only of protein. These proteinaceious infectious particles have been named prions. The known prion disease includes creutzfeldt-Jakob etc. while some prion diseases are inherited, others are apparently due to infection by eating infected tissue or inadvertently through medical procedures such as tissue transplants.

Modes of transmission

· Droplet contact: diseases that are commonly spread by coughing or sneezing include bacterial meningitis, chickenpox, common cold, influenza, mumps, streptococcal sore throat, tuberculosis, measles, rubella, and whooping cough

· Viral droplet Nuclei transmission: when viruses are shed by an infected person through coughing or sneezing into the air, the mucus coating on the virus starts to evaporate. Droplet nuclei are so microscopic that they are able to stay airborne indefinitely on the air currents present within indoor spaces. Viral diseases that are commonly spread by coughing or sneezing droplet nuclei include common cold, influenza A and B, mumps, measles, rubella, severe acute Respiratory syndrome.

· Faecal-oral transmission: foodstuffs or water become contaminated by people not washing their hands before preparing food, or untreated sewage being released into a drinking water supply, and people who eat or drink them become infected. Eg cholera, hepatitis A, polio, rotavirus diarrhoea, typhoid.

· Sexual transmission. Eg HIV/AIDS , chiamydia, genital warts, gonorrhoea, hepatitis B virus, syphilis, herpes viruses.

· Transmission by direct contact: disease that can be transmitted by direct contact are called contagious. It is important to note that contagiousness is not the same as infectious; although all contagious diseases are infectious but not all infectious disease are contagious.

· Vertical transmission. From mother to child

· Iatrogenic transmission: these are transmissions due to medical procedures such as injection or transplantation of infected material.

· Vector borne transmission: a vector is an organism that does not cause disease itself but that transmits infection by conveying pathogens from one host to another. Such as cholera.

OVERVIEW OF REPRODUCTIVE SYSTEM AND HEALTH.

Structure of the male reproductive system

Structurally, the male reproductive system may be divided into the following components: the testes(gonads), the duct system, accessory organs and external genitalia.

· The testes: the male gonads produce gametes (sperm) and hormones; testosterone and inhibin.

· The duct system: this consists of the epididymis, ductus (vas) deference and urethra. Sperm remain within the epididymis for about 3 weeks. During this time, they mature and acquire the ability to swim.

o The vas deferens, which carries sperm from the epididymis to the ejaculatory duct.

o The scrotum: this is a sack of cutaneous membrane that hangs outside the abdomino-pelvic cavity at the root of the penis. The paired testes (male gonads) are suspended within the scrotum, separated by a connective tissue septum.

Spermatogenesis

It is the total process of sperm formation. It consists of two phases. The first phases are meiosis, during which the primary spermatocytes (stem cells) divide, the second phase, known as spermiogenesis occurs in the seminiferous tubules. The entire process of spermatogenesis takes 64 to 72 days.

Semen is the liquid transport medium for sperm. It protects, activates, and facilitates the movement of sperm.

Structure of the female reproductive tract

The female reproductive system is structurally divided into three components: the ovaries (gonads), the duct system, accessory organs and external genitalia.

· The ovaries: it contains sac-like structures called follicles. The follicles contain the immature eggs known as oocytes.

· The duct system: the duct system of the female reproductive system comprises the uterine tube, the uterus and the vagina.

o The uterus is a hollow, thick-walled organ located between the urinary bladder and rectum. The uterus receives a fertilized egg, retains the fertilized egg and nourishes the fertilized egg.

o The vagina is the thin walled tube that sits between the bladder and rectum and extends from the cervix to the body exterior. It receives the penis and semen during sexual intercourse and provides a delivery route for an infant and for menstrual flow.

The menstrual cycle.

The menstrual cycle is regulated by cyclic production of oestrogens and progesterone. Each cycle is about 28 days in length and ovulation typically occurs about midway through cycle on day 14.

Puberty

Puberty refers to the stage of physical maturation in which an individual becomes physiologically capable of sexual reproduction.

Female secondary sexual characteristics

Secondary sexual development in girls involves the enlargement of the ovaries, uterus, vagina, labia, and breasts and growth of pubic hair. Between 11 and 14 years.

Male secondary sexual characteristics

Progressively, the testis increases in size, mainly at the expense of the seminiferous tubules. Slight progressive increase in scrotal folds, the secretion of testosterone, the growth of pubic hair, axillary hair appears around 13 years of age, body odour and lowering of the voice pitch, onset of sperm production.

Sexual transmitted infections.

Sexually transmitted infections are a group of contagious diseases in which the main mode of transmission is by sexual intercourse. They are often traditionally referred to as veneral diseases. Principal sites of infections include moist mucous surfaces such as penis, vagina and cervix.

Classification and types of STIs

Stis can be classified into two namely: aetiological classification and clinical classification.

· Aetiological classification: this is based on the aetiology or causative agent of STIS such as bacterial causes, viral causes, fungi and protozoa causes of STIs.

· The second classification method is based on the clinical presence or absence of genital ulcer, thus STIs can be classified either as genital ulcer disease or non-genital ulcer disease.

Signs and symptoms of STI

· Difficulty in passing urine

· Presence of genital ulcer

· Rectal discharge, rectal pain, rectal bruises.

· Difficulty in passing urine

· Presence of genital ulcers or sores

· Vaginal itching

· Difficulty in swallowing

· Hoarseness of voice

· Throat pain

INTRODUCTION TO EPIDEMIOLOGY AND TRANMISSION OF HIV

Definition

· Virus is the smallest known infective organism. They are also known as filterable agent that totally depend on the mechanisms of host cells for survival

· HIV; Human immunodeficiency virus.

Hiv types and subtypes

Hiv is a highly variable virus which mutates very readily. This means there are many different strains of HIV, even within the body of a single infected person. Hiv has been classified into two types, hiv-1 and hiv2. Both types are transmitted through the same mode

How hiv causes aids

Hiv infects and destroys cells of the immune system known as t-helper cells (CD4 bearing cells).

People who are no infected with HIV and generally are in good health have roughly 700 to 1200 CD4+ T cells per microliter.

HIV –related opportunistic infections and disease includes

· Bacterial desease such as tuberculosis, mycobacterium avium complex, bacterial pneumonia and septicaemia (blood poisoning).

· Protozoal diseases such as toxoplasmosis, microsporidiouses, cryptosporidiosis, isopsoriasis and leihmaniasis.

· Fungal diseases such as pneumonistic carini pneumonia, candidiasis, cruptococcosis and peniclilliosis

· Viral diseases such as those caused by cytomegalovirus, herpes simplex and herpes zoster virus

· HIV-associated malignancies such as kaposi’s sarcoma, lymphoma and squamous cell carcinoma.

· Tuberculosis is the number one opportunistic infection in Africa.

Host infectiousness

Host infectiousness is the ability of an infected individual to transmit infection to an uninfected individual.

Viral infectivity and virulence

Viral infectivity and virulence tend to relate directly to transmissibility.

Host susceptibility

It is the ability of an uninfected individual to become infected when exposed to an infection.

Ø Studies have shown that breastfeeding accounts for most mother-to-child transmission of HIV.

Ø Most infants who become infected during labour and delivery do so by sucking, imbibing, or aspirating maternal blood or cervical secretions that contains HIV.

Ø Incubation period is the time from infection with a pathogen to development of clinical symptoms.

Clinical symptoms of aids

· Rapid weight loss

· Dry cough

· Recurring fever

· Profuse night sweats

· Profound and unexplained fatigue

· Diarrhea that lasts for more than a week

· White spots or unusual blemishes on the tongue, in the mouth, or in the throat

· Pneumonia

· Red, brown, pink or purplish blotches on or under the skin or inside the mouth, nose, or eyelids.

· Memory loss, depression, and other neurological disorders.

· The only way to determine whether one is infected is to be tested for HIV infection using laboratory techniques.

Definition of terms in HIV

· Window period: this is the time from infection until a test can detect any change. The average window period with HIV-1 antibody tests is 4 weeks (ranging from 2 weeks to months). Antigen detection tests reduce the window period substantially.

· Sensitivity: the percentage of the results that will be positive when HIV is present

· Specificity: the percentage of the results that will be negative when HIV is not present.

· False positive: the test incorrectly indicates that HIV is present in a non-infected person.

· False negative: the test incorrectly indicates that HIV is absent in an infected person.

Factors influencing the spread of HIV

· HIV- associated stigma and discrimination: makes people to be afraid, even to see a doctor etc

· Socioeconomic status: if the poor cannot access test or treatment due to cost

· Cultural and traditional practices: widow inheritance

· War and armed conflicts: it includes the collapse of health and education services. Rape etc

· Drug and alcohol abuse

· Mass male circumcision and female genital mutilation

PREVENTION, CONTROL AND TREATMENT OF HIV/AIDS.

How HIV is not transmitted

· Hugging and shaking hands

· Coughing and sneezing

· Eating together

· Using toilet

· Sharing cups, dishes and cutlery

· Mosquito bites

HIV prevention measures

· Primary prevention strategies include HIV counselling, information and education, sensitization and promotion of positive healthy behaviours.

· Secondary HIV prevention involves early diagnosis

· Tertiary HIV control helps to minimize complications and disabilities that may arise from the epidemic like deaths, irreversible kidney or liver damage and to eliminate new cases by measures including intensifying clinical trials to discover vaccines for preventing HIV or providing cure.

Prevention of sexual transmission of HIV

· A abstinence

· B being faithful

· C condom

· D desist from sharing needles

· E encourage voluntary counselling and testing

· F facilitate a society free of stigma and discrimination.

GENETIC DISORDER AND NON-COMMUNICABLE DISEASE IN AFRICA

The NCDs that will be discussed include: hypertension, ischaemic heart disease, cerebrovascular disease, cancer of various organs, terminal diseases of the major organs (liver, heart, kidney), chronic obstructive airways diseases and dementia.

· Hypertension is best described as a silent killer, because it surreptitiously causes tissue and organ damage without the person afflicted knowing. The susceptible organs are the heart, brain, kidneys, eyes and the blood vessels.

· Dementia also referred to as brain failure is defined as deterioration in cognitive skills resulting in a decline in the ability to perform the activities of daily living and warranting supervision in the advanced stages.

· Cancer results when cells proliferate uncontrollably and result in tissue destruction, mass lesions and failure of organs

Sickle cell disease as a prototype

Haemoglobin

It is the red pigment in the red cell which carries oxygen around the body.

Definition of terms

Sickle cell disease is the condition resulting from the inheritance of two abnormal allelemorphic genes controlling the formation of the I globin chains of haemoglobin, at least one of which is the sickle HbS gene. Sickle cell anaemia is the condition resulting from the inheritance of two sicke Hb genes.

Causes and processes that lead to disease

Sickle cell disease is an inherited blood disorder that affects how oxygen is carried in the body, characterized by a modification of the red cell from a doughnut-shape into a crescent or half-moon shape.

· People who have sickle cell trait (AS) are much less likely to suffer from a serious attack of malaria than people who are homozygous (AA).

· Symptoms of sickle cell start from early infancy, usually after 6 months of life.

· Painful episodes are treated with pain reliever (analgesics) ranging from mild to very strong analgesic depending on severity of pain.

Psychosocial issues

The symptomatic SCD patient will have to deal with pains, loss of school time, job complication, setting limits on having fun, it may also affect relationship and having children. In some instances, there may be a need to avoid age appropriate activities such as football. The consequence of this is that peer relationship is compromised. This can lead to a sense of isolation and depression is some SDC persons.

DRUGS AND MANKIND

A drug is a pharmaceutical product used in or on the human body for the prevention, mitigation, diagnosis and/or treatment of diseases, or for the modification of physiological function.

Drugs are used for 3 principal reasons

· To cure disease

· To control or eliminate symptoms

· To arrest disease progression

· To prevent disease.

Routes of drug administration

· Systemic: the drug is taken inside the body and it is absorbed into the system. Eg. Chloroquine, fansidar

· Non-systemic: the drug is either taken inside or rubbed on the body, but it is not absorbed into the blood (circulatory) system.

Sources of drugs

· Natural

· Synthetic

· Semi-synthetic

Classification of drugs according to disease and symptoms

· Analgesics: drugs used to relieve pain e.g paracetamol

· Antipyretic: lowers body temperature in fever condition

· Anti-inflammatory: treats pain and inflammation such as in arthritis eg ibuprofen, indomethacin

· Opioid analgesic: (narcotics): used to relieve moderate to severe pain such as in cancer patients.

Adverse drug reactions and pharmacovigilance

The WHO defines adverse drug reactions as a response to a medicine, which is noxious (unwanted or harmful (and unintended, and which occurs at doses normally used in human for the prophylaxis, diagnosis or therapy of disease, or for the modification of physiological function.

Drug abuse/misuse

Any taking of a drug, which harms or threatens to harm the physical or mental health or social well-being of an individual or other individuals or/of society at large or which is illegal. E.g injecting illicit heroin, diazepam overdose etc

Drug addiction means a state of periodic or chronic intoxication produced by repeated consumption of a drug; natural or synthetic. It is characterized by

· Overwhelming desire or need (compulsion) to continue taking the drug and to obtain it by any means.

· A tendency to increase the dose

· A psychic (psychological) and generally a physical dependence on the effects of the drugs

· Detrimental effect on the individual and on the society.

Ø Tolerance: is an adaptive state characterized by diminished response to the same quantity of drug or by the fact that a large dose is required to produce the same degree of pharmocodynamic effect or response.

Ø Opiods- substances that are naturally present in opium or that can be derived chemically from opium. E.g morphine, codeine, heroin methadone, pethidine.

Ø Sedatives: usually used to control anxiety, convulsions, hallucinations medically but can be musuded.

Rational drug use

Rational drug use. Appropriate drug be prescribed, that it be available at the right time, at a price people can afford, that it be dispensed correctly and that it be taken in the right dose at the right intervals and for the right length of time.

There are three major actors that should be targeted for rational drug use:

· Prescribers/physicians

· Pharmacists

· Patients.

SUMMARY OF GES 107, REPRODUCTIVE HEALTH