Disease has been on earth as long as there has been life. All types of life on earth is affected in some fashion by disease. Bacteria, Viruses, Parasites, Fungus and even a newer form called Prions cause disease ranging from mild to fatal. During the golden age of Microbiology, new knowledge was learned by research which builds the basic level of facts we now have on controlling the spread of disease. Joseph Lister developed techniques which are the basis for aseptic techniques in modern surgery. Louis Pasteur in his research determined that bacteria does not spontaneously generate but instead bacteria must be introduced into a system for infection to take place. Pasteur was a scientist very much ahead of his time, but he was criticized by his colleagues for being a quack and challenging what was the common thinking of all scientists at this time.
The discoveries of Lister and Pasteur paved the way for the discovery of Penicillin in 1928 by Sir Alexander Fleming. Until Fleming discovered penicillin by accident in his lab, Sulfa Drugs were the best weapon that medicine had against the ravages of bacterial disease. Penicillin was called the “magic bullet” and hailed as the end of bacterial disease as it was known. The timing of this discovery was key as now medicine had to turn it’s attention to viral diseases to create vaccines which could reduce deaths from childhood diseases like Rubella and Measles.
Over the 82 years since the discovery of penicillin, medicine, science and public health have worked (sometimes together and other times separately) on new forms of antibiotics, vaccines and other cures to diseases from the past and against newer, emerging infections. Great strides have been made as Smallpox was declared eradicated in the 1980’s and currently the World Health Organization (WHO) and it’s member countries are making Polio a priority for eradication by the next decade worldwide. However, as the microbial soup continues to evolve, human behavior changes and major changes occur in the ecology be they man made or natural has presented new challenges for disease control and eradication. HIV, Bird Flu, H1N1 (Swine Flu) and Prion dieases such as Cruzfeld-Jacob Dieases (CJD) are now the major challenges which currently test the limits of scientific discovery, medical intervention and the resources of public health. Add to this list the ever looming threat of bioterrorism and the potential of millions being affected with Anthrax, Plague or Botulism places additional pressure on the public health preparedness network to ensure that the country is ready in the event of a biological attack.
In the 20th and now the 21st Century, it is conceivable to be on the other side of the world in a matter of hours. Anyone with a slowly incubating disease who boards a plane in New York headed to Europe or Asia can in theory infect many on a plane ride or many that they come in contact with when they arrive at their destination. During this World Cup which will end this Sunday, a traveler from Australia returned home from South Africa with Measles. Travel has had a huge impact on the spread of disease globally. No country can restrict all travel but each country has health guidelines as to who may come into their country.
As I mentioned, travel is not the only factor which has an impact on global spread of disease. Changing ecology can present new diseases that once were not known. Lyme Disease is a prime example of this factor. Edging closer into the realm of nature bought people in contact with deer ticks who are vectors or carriers of the spirochete which causes Lyme disease. Microbial adaption has put us at a crossroad in scientific research in antibiotic creation. Many bacterial diseases have developed mechanisms which allow them to fight off the effectiveness of a majority of antibiotics. Research into the genetics of bacteria as well as viruses will help in discovery of new, more effective drugs. Human Behavior is not something that can be easily controlled. The choices we make, especially in with our bodies have a major impact on ourselves and others. The rise in rates of STD’s nationwide are a prime example of choices made. Coinfections with HIV and Syphilis are common and the combination makes treatment of either disease very difficult.
The factors that contribute to disease have many elements. Each one that I have presented only shows a basic illustration of the issue. Emerging diseases have many elements to their appearance and each can be debated differently by all sides (medicine, research science and public health) as to how each factor plays into the prevalence of the disease in the community.