المرحلة الرابعة اعداد د. وفاء محمود جاسم Water-borne diseases المرحلة الرابعة اعداد د. وفاء محمود جاسم

Main Subjects 1- What are water-borne diseases? 2- What are the main ways for transmission ? 3-What are the general measures for prevention ? 4- What is cholera ,signs and symptoms, cause and risk factors ? 5-The main response of WHO ? 6- What is brucellosis ?

Water-borne diseases Water-borne diseases are any illness caused by drinking water contaminated by human or animal faeces, which contain pathogenic microorganisms Like salmonellosis, cholera, shigellosis)

Transmission Water borne diseases spread by contamination of drinking water systems with the urine and faeces of infected animal or people. This is likely to occur where public and private drinking water systems get their water from surface waters (rain, rivers, lakes etc.), which can be contaminated by infected animals or people.

Prevention 1- Clean water is Important for reducing the spread of water-borne diseases. 2- safe disposal of faeces.  3- Disinfection is used to prevent the growth of pathogenic organisms and to protect public health.  4- The two most common methods to kill microorganisms in the water supply are: oxidation with chemicals such as chlorine, chlorine dioxide or ozone, and irradiation with Ultra-Violet (UV) radiation.

Cholera It is an acute infection of the intestine, which begins suddenly with painless watery diarrhea, nausea and vomiting. Most people who become infected have very mild diarrhea or symptom-free infection. Severe cholera cases present with profuse diarrhea and vomiting. Severe, untreated cholera can lead to rapid dehydration and death. If untreated, 50% of people with severe cholera will die, but prompt and adequate treatment reduces this to less than 1% of cases.

Cholera Cholera outbreaks can occur sporadically in any part of the world where water supplies, sanitation, food safety and hygiene practices are inadequate. Overcrowded communities with poor sanitation and unsafe drinking-water supplies are most frequently affected.

The World Health Organization says that every year more than 3 The World Health Organization says that every year more than 3.4 million people die as a result of water related diseases, making it the leading cause of disease and death around the world. Most of the victims are young children, the vast majority of whom die of illnesses caused by organisms that thrive in water sources contaminated by raw sewage

Symptoms Cholera is an extremely virulent disease. It affects both children and adults and can kill within hours. About 80% of people infected with V. cholerae do not develop any symptoms, although the bacteria are present in their faeces for 1-10 days after infection and are shed back into the environment, potentially infecting other people. Among people who develop symptoms, 80% have mild or moderate symptoms, while around 20% develop acute watery diarrhoea with severe dehydration. This can lead to death if left untreated.

The cause Cholera is caused by the bacterium Vibrio cholerae. People become infected after eating food or drinking water that has been contaminated by the faeces of infected persons. Raw or undercooked seafood may be a source of infection in areas where cholera is prevalent and sanitation is poor.

Risk factors and disease burden Cholera transmission is closely linked to inadequate environmental management. Typical at-risk areas include 1-peri-urban slums, where basic infrastructure is not available 2- camps for internally displaced persons or refugees . 3- Dead bodies have never been reported as the source of epidemics. Cholera remains a global threat to public health and a key indicator of lack of social development.

Prevention and control The long-term solution for cholera control lies in: 1- Preventive measures 2-Control of patient , contact and environment 3- Epidemic measures

WHO response 1-support the design and implementation of global strategies to contribute to capacity development for cholera prevention and control globally; 2-provide a forum for technical exchange, coordination, and cooperation on cholera-related activities to strengthen countries’ capacity to prevent and control cholera; 3- support countries for the implementation of effective cholera control strategies and monitoring of progress; 4-disseminate technical guidelines and operational manuals;

5-support the development of a research agenda with emphasis on evaluating innovative approaches to cholera prevention and control in affected countries; 6-increase the visibility of cholera as an important global public health problem through the dissemination of information about cholera prevention and control 7- conducting advocacy and resource mobilization activities to support cholera prevention and control at national, regional, and global levels.

Brucellosis Brucellosis,  Crimean fever, Malta fever, Maltese fever, Mediterranean fever, rock fever, or undulant fever It  is a highly contagious zoönosis caused by ingestion ofunpasteurized milk or undercooked meat from infected animals or close contact with their secretions.

Brocella species are small, Gram-negative, nonmotile, nonspore-forming, rod-shaped (coccobacilli) bacteria., which usually persists for life. Four species infect humans:  B. melitensis, B. abortus, B. suis, and B. canis.  1- B. melitensis is the most virulent and invasive species; it usually infects goats 2- B. abortus is less virulent and is primarily a disease of cattle.  3-B. suis is of intermediate virulence and chiefly infects pigs.  4-B. canis affects dogs.

Signs and symptoms In the first stage of the disease, septicaemia occurs and leads to the classic triad of undulant fevers, 1-sweating (often with characteristic smell, likened to wet hay) 2-migratory arthralgia and myalgia (joint and muscle pain). Blood tests characteristically reveal leukopenia and anemia, and demonstrate positive Bengal Rose and.

Diagnosis 1- Demonstration of the agent: blood cultures in tryptose broth, bone marrow cultures.. 2- Demonstration of antibodies against the agent with the classic Bengal Rose reactions, 3- Histologic evidence of granulomatous hepatitis on hepatic biopsy 4- Radiologic alterations in infected vertebrae:.

Risk Factors for Brucellosis Eat or drink unpasteurized dairy products from cows, goats, or other animals that are infected with the bacteria Eat other unpasteurized cheeses called "village cheeses." These come from high-risk regions, including the Mediterranean Travel to areas where Brucella is common Work in a meat-processing plant or slaughterhouse Work on a farm

Prevention Do not drink or eat unpasteurized dairy products. Wear rubber gloves if you work in the animal processing industry. If you have come in contact with an animal infected with Brucella, notify  health care provider -- even if there is no symptoms. The need for monitoring for at least six months.