Factors contributing to fall and or rise of infectious diseases Flashcards
Driving factors contributing to fall of infectious diseases
Hygiene and sanitation • Improved socio-economic conditions • Elimination of vectors and reservoirs • The era of antimicrobial therapy • Immunization – second to clean and safe water has made the biggest impact
Define Emerging infectious diseases
: infectious disease that has newly appeared in a population
(caused by a ‘novel’ pathogen) or that has been known for some time
but is rapidly increasing in incidence or geographic range
• Emerging infections account for ~ 12% of all human infections; the
majority are zoonoses
Give examples of Emerging Infectious Diseases
Ebola virus (first outbreaks 1976; virus isolated in 1977)
• Enterohemorrhagic E coli e.g. serotype O157:H7 (1982)
• HIV/AIDS (virus first isolated in 1983)
• Zika virus (first isolated in 1947)
• Lujo arenavirus – novel pathogen (2008)
• MERS Coronavirus – novel pathogen (September 2012)
Define Re-emerging Infectious diseases
REID: Infection that had decreased in incidence in the global
population and was brought under control through effective
healthcare policy and improved living conditions reached a nadir and,
more recently, began to resurge as a health problem due to changes
in the health status of a susceptible population
Give examples of re-emerging diseases
Examples include: • Tuberculosis • Cholera • Dengue • Diphtheria, etc.
Chronic Diseases For Which An Infectious
Etiology Has been Established
Cervical cancer - Human papillomavirus
Chronic hepatitis, liver cancer -Hepatitis B and C
Lyme disease (arthritis)- Borrelia Burgdorferi
Bladder cancer-Schistosoma haematobium
Peptic ulcer disease -helicobactor pylori
Chronic Diseases For Which An Infectious
Etiology Has been Established
Atherosclerosis (CHD) Diabetes mellitus, type 1 Multiple sclerosis Inflammatory bowel disease Cause Chlamydiae pneumoniae Enteroviruses (esp. Coxsackie) Epstein-Barr v Role of gut microbiome
Factors Contributing To The Rise In Infectious Diseases 3:
Demographic, Environmental & Sociopolitical Factors
- Technology -eg building of dams accompanied by snail population
- Excessive antibiotic use results in carbapenemase resistance and pan-resistant bacteria
- Contributing factors; Accompanying material eg plants
- Modes of transport eg busses (Odyssean malaria)
- Deforestation and ecosystem encroachment eg eboli virus
actors Contributing To The Rise In Infectious
Diseases 2: Microbial Factors
Microbial adaptation – Environmental survival – Acquisition of genes coding for virulence; mutations resulting in hyper-virulence – Antimicrobial resistance – Genetic variation
Factors Contributing To The Rise In Infectious
Diseases 3: Demographic, Environmental &
Sociopolitical Factors
Poverty • Malnutrition • Unsafe water • Public health infrastructure or policy breakdown • ’Escaping’ immunization strategies • Warfare
Factors Contributing To The Rise In Infectious Diseases 6:
Environmental & Sociopolitical Factors – Consequences of
Global Warming
Flooding of sea-level areas • Droughts in previously temperate climates • Forced migration • Possible decreases in food production and availability of potable water • Vector redistribution • Increase in population stress • Increase in conflict after population disruption
Conclusions
- Infectious disease are dynamic and are not caused by new pathogens
- Microbes involved in re-emergence and emergence of infectious diseases cross taxononomic lines to include viruses, bacteria, parasistes, fungi
Conclusion
- Human activities are the driving factor for emergence of disease
- Social ,policalm,climate,technology and enviromental factors influence the emergence of diseases
- Responding and understanding an infectious disease requires a global effort
