Diseases

THEIR TRANSMISSION AND CONTROL
This project is designed to inform or further the reader’s knowledge about the different diseases and how they are transmitted and can be controlled. Therefore, it is divided into three (3) major sections. These sections includes: water borne diseases, food borne diseases and air borne diseases. These subtopics will go into further details as to make it simpler for your understanding.

TABLE OF CONTENTS

INTRODUCTION
WATER BOURNE DISEASES
FOOD BOURNE DISEASES
AIR BOURNE DISEASES

ACKNOWLEDGEMENT

First I would like to thank the Lord who is the head of my life who has given me the strength, courage, and inspiration in completing this assessment. I would also like to thank my teacher who has helped me in every step of the way. I would also like to thank my friends and family, specifically my parents who has provided the necessary resources needed to complete this assessment and also in giving me the ongoing encouragement and assistance.
Once again I say thank you.

WATER BOURNE DISEASES

HOOKWORM
Hookworm is an intestinal parasite of humans. The larvae and adult worms live in the small intestine can cause intestinal disease. The two main species of hookworm infecting humans are Anclostoma duodenale and Necator americanus.

Hookworm eggs are passed in the faeces of an infected person. If an infected person defecates outside (near bushes, in a garden, or field) or if the faeces from an infected person are used as fertilizer, eggs are deposited on soil. They can then mature and hatch, releasing larvae (immature worms). The larvae mature into a form that can penetrate the skin of humans. Hookworm infection is transmitted primarily by walking barefoot on contaminated soil. One kind of hookworm (Anclostoma duodenale) can also be transmitted through the ingestion of larvae.
Itching and a localized rash are often the first signs of infection. These symptoms occur when the larvae penetrate the skin. A person with a light infection may have no symptoms. A person with a heavy infection may experience abdominal pain, diarrhoea, loss of appetite, weight loss, fatigue and anaemia. The physical and cognitive growth of children can be affected.
How can I prevent infection?
Do not walk barefoot in areas where hookworm is common and where there may be faecal contamination of the soil. Avoid other skin-to-soil contact and avoid ingesting such soil. Faecal contamination occurs when people defecate outdoors or use human faeces as fertilizer.The infection of others can be prevented by not defecating outdoors or using human faeces as fertilizer, and by effective sewage disposal systems.
What is preventive treatment?
In developing countries, groups at higher risk for soil-transmitted helminth infections (hookworm, Ascaris, and whipworm) are often treated without a prior stool examination. Treating in this way is called preventive treatment (or "preventive chemotherapy"). The high-risk groups identified by the World Health Organization are preschool and school-age children, women of childbearing age (including pregnant women in the 2nd and 3rd trimesters and lactating women) and adults in occupations where there is a high risk of heavy infections. School-age children are often treated through school-health programs and preschool children and pregnant women at visits to health clinics.

Schistosomiasis
Schistosomiasis (also known as bilharzia, bilharziasis or snail fever) is a collective name of parasitic diseases caused by several species of trematode belonging to the genus Schistosoma. Snails serve as the intermediary agent between mammalian hosts. Individuals within developing countries who cannot afford or obtain proper water and sanitation facilities are often exposed to water contaminated by the infected snails. Signs and symptoms are abdominal pain, cough, diarrhoea, eosinophilia — extremely high eosinophil2 granulocyte (white blood cell) count. Fever, Fatigue, Hepatosplenomegaly — the enlargement of both the liver and the spleen. The infection cycle begins when fresh (not salt) water becomes infected with the eggs of the parasite through faeces and urine of infected humans. The eggs hatch in the water and the worms reproduce inside the water snails. Tiny cercariae (larvae) are released into the water - the larvae can survive for up to 48 hours in the water.
The cercariae can penetrate human skin and enter our bloodstream. In the bloodstream they travel through the blood vessels of the lungs and liver, and then to the veins around the bowel and bladder.
Some weeks later the worms are mature - they mate and start producing eggs. These eggs pass through the walls of the bladder and/or intestine and eventually leave the body through urine or faeces; and thus the cycle starts again. Prevention is best accomplished by eliminating the water-dwelling snails that are the natural reservoir of the disease. Acrolein, copper sulphate, and niclosamide can be used for this purpose. Recent studies have suggested that snail populations can be controlled by the introduction of, or augmentation of existing, crayfish populations. Praziquantel - a medication which is given as a short course generally clears up the infection. Even patients in advanced stages will be effectively treated. However, the medication does nothing to prevent re-infection.

Gastroenteritis

Gastroenteritis or infectious diarrhoea is a medical condition characterized by inflammation ("-itis") of the gastrointestinal tract that involves both the stomach ("gastro"-) and the small intestine ("entero"-), resulting in some combination of diarrhoea, vomiting, and abdominal pain and cramping
Globally, most cases in children are caused by rotavirus. In adults, norovirus and Campylobacter are more common. Less common causes include other bacteria (or their toxins) and parasites. Transmission may occur due to consumption of improperly prepared foods or contaminated water or via close contact with individuals who are infectious.
The key treatment is enough fluids. For mild or moderate cases, this can typically be achieved via oral rehydration solution (a combination of water, salts, and sugar). For more severe cases, intravenous fluids from a healthcare centre may be needed. Gastroenteritis primarily affects children and those in the developing world.

* Wash your hands thoroughly after going to the toilet and before eating or preparing food. * Clean the toilet, including the seat and handle, with disinfectant after each bout of vomiting or diarrhoea. * Don't share towels, flannels, cutlery and utensils with other household members

Typhoid
Typhoid fever is a life-threatening illness caused by the bacterium, Salmonella Typhi. Salmonella Typhi lives only in humans. Persons with typhoid fever carry the bacteria in their bloodstream and intestinal tract. In addition, a small number of persons, called carriers, recover from typhoid fever but continue to carry the bacteria. Both ill persons and carriers shed Salmonella Typhi in their faeces (stool).
You can get typhoid fever if you eat food or drink beverages that have been handled by a person who is shedding Salmonella Typhi or if sewage contaminated with Salmonella Typhi bacteria gets into the water you use for drinking or washing food. Therefore, typhoid fever is more common in areas of the world where hand washing is less frequent and water is likely to be contaminated with sewage.
Once Salmonella Typhi bacteria are eaten or drunk, they multiply and spread into the bloodstream. The body reacts with fever and other signs and symptoms. Persons with typhoid fever usually have a sustained fever as high as 103° to 104° F (39° to 40° C). They may also feel weak, or have stomach pains, headache, or loss of appetite. In some cases, patients have a rash of flat, rose-colored spots. Ways in which one can control typhoid are: * Wash your hands. * Avoid drinking untreated water. * Avoid raw fruits and vegetables * Choose hot foods. Treatment is offered in the form of vaccination. It can be taken either orally (capsule) or by injection.

Cholera
Cholera is an infection of the small intestine caused by the bacterium Vibrio cholerae.
The main symptoms are watery diarrhoea and vomiting. Transmission occurs primarily by drinking water or eating food that has been contaminated by the faeces (waste product) of an infected person, including one with no apparent symptoms. Severe cholera, requiring hospitalization, results from the accumulation of about a million bacterial cells within the body.
The severity of the diarrhoea and vomiting can lead to rapid dehydration and electrolyte imbalance, and death in some cases. The primary treatment is oral rehydration therapy, typically with oral rehydration solution, to replace water and electrolytes. If this is not tolerated or does not provide improvement fast enough, intravenous fluids can also be used. Antibacterial drugs are beneficial in those with severe disease to shorten its duration and severity.

FOOD BOURNE DISEASES
Botulism
Botulism (Latin, botulinus) is, in humans, a rare and sometimes fatal paralytic illness. Food borne botulism is an intoxication caused by consuming food contaminated with the botulinum toxin; it is not passed on from person to person when the skin is intact. Infant botulism is a toxico-infection where the gastro-intestinal tract is colonized by spores prior to the protective intestinal bacterial flora having developed and wound botulism is found most often among substance abusers when spores enter a wound under the skin and, in the absence of oxygen, are activated and release toxin. Some signs and symptoms are: the muscle weakness of botulism characteristically starts in the muscles supplied by the cranial nerves. A group of twelve nerves controls eye movements, the facial muscles and the muscles controlling chewing and swallowing. Double vision, drooping of both eyelids, loss of facial expression and swallowing problems may therefore occur, as well as difficulty with talking. The weakness then spreads to the arms (starting in the shoulders and proceeding to the forearms) and legs (again from the thighs down to the feet. When canning or preserving food at home, pay attention to hygiene, pressure, temperature, refrigeration and storage. When making home preserves, bottle only acidic fruit such as apples, pears, stone fruits and berries. Tropical fruit and tomatoes are low in acidity and must have some acidity added before they are bottled.Oils infused with fresh garlic or herbs should be acidified and refrigerated. Potatoes which have been baked while wrapped in aluminium foil should be kept hot until served or refrigerated. Because the botulism toxin is destroyed by high temperatures, home-canned foods are best boiled for 10 minutes before eating. Metal cans containing food in which bacteria, possibly botulinum, are growing may bulge outwards due to gas production from bacterial growth; such cans should be discarded.Any container of food which has been heat-treated and then assumed to be airtight which shows signs of not being so, e.g., metal cans with pinprick holes from rust or mechanical damage, should also be discarded. Contamination of a canned food solely with C. botulinum may not cause any visual defects (e.g. bulging). Only sufficient thermal processing during production should be used as a food safety control. Botulism can be treated by inducing passive immunity with a horse-derived antitoxin, which blocks the action of toxin circulating in the blood.
Apart from botulism, other common food borne diseases are typhoid, cholera and gastroenteritis.
AIR BORNE DISEASES

Colds
The common cold (also known as nasopharyngitis, rhinopharyngitis, acute oryza, head cold, or simply a cold) is a viral infectious disease of the upper respiratory tract which primarily affects the nose. Symptoms include coughing, sore throat, runny nose, sneezing, and fever which usually resolve in seven to ten days, with some symptoms lasting up to three weeks. Well over 200 virus strains are implicated in the cause of the common cold; the rhinoviruses are the most common.
Upper respiratory tract infections are loosely divided by the areas they affect, with the common cold primarily affecting the nose, the throat (pharyngitis), and the sinuses (sinusitis), occasionally involving either or both eyes via conjunctivitis. Symptoms are mostly due to the body's immuneresponse to the infection rather than to tissue destruction by the viruses themselves. The primary method of prevention is by hand washing with some evidence to support the effectiveness of wearing face masks. The common cold may occasionally lead to pneumonia, either viral pneumonia or secondary bacterial pneumonia.
No cure for the common cold exists, but the symptoms can be treated. It is the most frequent infectious disease in humans with the average adult contracting two to three colds a year and the average child contracting between six and twelve.
The typical symptoms of a cold include cough, runny nose, nasal congestion and a sore throat, sometimes accompanied by muscle ache, fatigue, headache, and loss of appetite. The only possibly useful ways to reduce the spread of cold viruses are physical measures such as hand washing and face masks; in the healthcare environment, gowns and disposable gloves are also used.

Influenza
Influenza, commonly known as "the flu", is an infectious disease of birds and mammals caused by RNA viruses of the family Orthomyxoviridae, the influenza viruses. The most common symptoms are chills, fever, runny nose, sore throat, muscle pains, headache (often severe), coughing, weakness/fatigue and general discomfort. Although it is often confused with other influenza-like illnesses, especially the common cold, influenza is a more severe disease caused by a different type of virus.[1] Influenza may produce nausea and vomiting, particularly in children,[2] but these symptoms are more common in the unrelated gastroenteritis, which is sometimes inaccurately referred to as "stomach flu" or "24-hour flu".
Typically, influenza is transmitted through the air by coughs or sneezes, creating aerosols containing the virus. Influenza can also be transmitted by direct contact with bird droppings or nasal secretions, or through contact with contaminated surfaces. Airborne aerosols have been thought to cause most infections, although which means of transmission is most important is not absolutely clear.[4] Influenza viruses can be inactivated by sunlight, disinfectants and detergents.[5][6] As the virus can be inactivated by soap, frequent hand washing reduces the risk of infection.[7] Flu can occasionally lead to pneumonia, either direct viral pneumonia or secondary bacterial pneumonia, even for persons who are usually very healthy.[8][9][10] In particular it is a warning sign if a child (or presumably an adult) seems to be getting better and then relapses with a high fever as this relapse may be bacterial pneumonia.[11] Another warning sign is if the person starts to have trouble breathing.[10]
Vaccinations against influenza are usually made available to people in developed countries.

Tuberculosis

Tuberculosis, MTB, or TB (short for tubercle bacillus), in the past also called Phthisis or Phthisis pulmonalis, is a common, and in many cases lethal, infectious disease caused by various strains of mycobacterium, usually Mycobacterium tuberculosis. Tuberculosis typically attacks the lungs, but can also affect other parts of the body. It is spread through the air when people who have an active TB infection cough, sneeze, or otherwise transmit respiratory fluids through the air.[2] Most infections are asymptomatic and latent, but about one in ten latent infections eventually progresses to active disease which, if left untreated, kills more than 50% of those so infected.
The classic symptoms of active TB infection are a chronic cough with blood-tinged sputum, fever, night sweats, and weight loss (the latter giving rise to the formerly prevalent term "consumption"). Infection of other organs causes a wide range of symptoms. Diagnosis of active TB relies on radiology (commonly chest X-rays), as well as microscopic examination and microbiological culture of body fluids. Diagnosis of latent TB relies on the tuberculin skin test (TST) and/or blood tests. Treatment is difficult and requires administration of multiple antibiotics over a long period of time. Social contacts are also screened and treated if necessary. Antibiotic resistance is a growing problem in multiple drug-resistant tuberculosis (MDR-TB) infections. Prevention relies on screening programs and vaccination with the bacillus Calmette–Guérin vaccine.