Biological Hazards Disease in Developed and Developing Countries

What are biological hazards?  Nontransmissible diseases: not caused by living organisms  Cardiovascular disease, cancer, diabetes, bronchitis, emphysema, and malnutrition  Transmissible diseases - caused by living organisms - can be spread from person to person  Pathogens – infectious agents  Vectors – insects and non human carriers

What factors affect the spread of disease?  Migration to urban areas  Reducing biodiversity by destroying forests and wiping out species that control vectors  Increased cultivation of rice - causes mosquito populations to increase  Increased international air travel  Climate change  Natural disasters such as floods  Some bacteria are becoming resistant to antibiotics  Virulent strains of influenza may develop  Bioterrorism

Case Study: Antibiotic-Resistant Staph  Methicillin-resistant Staphylococcus aureus (MRSA) infection is caused by a strain of staph bacteria that's become resistant to the antibiotics commonly used to treat staph infections.  Most infections occur in people who've been in hospitals or other health care settings.  Infections are associated with invasive procedures or devices  Another type of MRSA infection has occurred among healthy people. This form often begins as a painful skin boil.  It's spread by skin-to-skin contact. At-risk populations include groups such as high school wrestlers, child care workers, and people who live in crowded conditions.

Case Study: Antibiotic-Resistant Staph  How does this occur?  Nature of the beast—highly reproductive  Overuse of antibiotics—at least half of all antibiotics used to treat humans are prescribed unnecessarily  In some countries, antibiotics are even available without a prescription.  Livestock are given massive amounts of antibiotics to prevent infection.

Case Study: Global Threat from AIDS  Worldwide, 400 million people are infected with an STD each year.  One in three in the US will contract an STD by age 24.  Infection rate for HIV/AIDS is increasing every year.  Long incubation period for the virus means more spreading.  Poorest countries can not afford to treat the disease or to test for it.  AIDS has caused the life expectancy of 700 million people living in sub- Saharan Africa to drop from 62 to 47 years.

Case Study: Global Threat from AIDS  Why is it so bad in Africa?  “Concurrency”  Economic Factors  Medical Suspicion  Pharmaceutical Industry  AIDS-deniers in politics  What are some ways of reducing infection?  Shrink the number of people capable of infecting others by reducing the number of new infections below the number of deaths.  Concentrate on the groups in a society most likely to spread the disease.  Use mass advertising and education programs to educate people.  Provide free or low-cost treatment to slow the progress of the disease.

How can we reduce the incidence of infectious disease?  Increase research on tropical diseases and vaccines  Reduce poverty  Decrease malnutrition  Improve drinking water quality  Reduce unnecessary use of antibiotics  Educate people to take all of an antibiotic prescription  Reduce antibiotic use to promote livestock growth  Careful hand washing by all medical personnel  Immunize children against major viral disease  Oral rehydration for diarrhea victims  Global campaign to reduce HIV/AIDS