Sanitation Issues in Managing Human Wastes  

1.  Objective

The objective is to introduce the types diseases of humans and plants caused by organisms and factors influencing their occurrence, distribution and control.

2.  Epidemiology

2.1.  Definitions

epidemiology

- study of occurrence, distribution, and control of diseases in populations

- origin, spread or communication, and eradication of disease

incidence - number of diseased individuals in a defined population
prevalence - proportion of diseased population (i.e. percent)
endemic - constantly present disease
epidemic - abnormally high incidence locally
pandemic - abnormally high incidence over a wide geographic area
outbreak - short-term local increase in a disease
morbidity - all cases, fatal and nonfatal
mortality - fatal cases
herd immunity - if the proportion of immune individuals is sufficiently high, then the whole population is protected

2.2.  Patterns of Disease in Developed Versus Underdeveloped Countries

Causes of death worldwide
Causes of death in developed and emerging countries
Recent worldwide outbreaks

3.  Organisms, Diseases, Symptoms

3.1.  Viruses

3.2.  Bacteria

3.2.  Other Organisms

3.3.  Recreation Water Pathogens

3.  Waterborne

3.1.  Table of Waterborne Diseases

3.2.  Protozoa

Giardia
Cryptosporidium

3.3.  Recent Outbreaks

Cryptosporidium - 400,000 cases in Milwaukee in 1993; probably related to contamination of drinking water by cattle; highly resistant to chlorination
Escherichia coli O157:H7 - a new highly pathogenic strain
Pfiesteria - a dinoflagellate caused by nutrient discharge in waters; causes memory loss and other symptoms

4.  Foodborne

4.1.  Foodborne Infections and Poisons

4.2.  Food Poisoning

Staphylococcus
Clostridium perfringens
botulism
aflatoxins

4.3.  Food Infection

salmonellosis
hepatitis

5. Control of Epidemics

5.1.  Improved resistance
nutrition
reduce people concentration
lighter work loads

5.2.  Control reservoir
mosquitoes
immunize animals (e.g. rabies)

5.3.  Control transmission
direct contact
food
water
air
feces

4.4.  Control of Waterborne Pathogens

Steps in control
prevent undisinfected feces from entering surface and ground water
treat all sewage using latrines, septic tanks, and waste treatment plants
treat all potentially impure water prior to domestic use (boil, filtration, disinfectants)
maintain disinfectant residual from treatment source to user
Indicator organisms
non-pathogenic organisms of intestinal origin that survive longer than pathogens in the environment
fecal coliform, total coliform, fecal streptococci (enterococci)
most probable number multiple tube fermentation test
membrane filter apparatus
membrane filter results for total and fecal coliform and enterococci
Bacteriological drinking water and recreational freshwater standards
Waste treatment
Water treatment, water filtration
Disinfection (halogination, heat, ozone, uv)
Effect of water and waste treatment

4.5.  Control of Food Pathogens

Prevention of Food Spoilage

heat
cool
preservatives
disinfectants
canning and packaging
drying
fermenting
irradiation

 

Prevention of Food Contamination

wash with clean water
use clean additives (e.g. water and milk)
used clean dishes and foodware
worker sanitation
clean animals
clean soils for growth