PREVENTION, TREATMENT & CONTROL: How can the spread of infectious…
PREVENTION, TREATMENT & CONTROL:
How can the spread of infectious diseases be controlled?
Effectiveness of pharmaceuticals
little incentive to develop new drugs however it is badly needed due to development of resistance.
new drugs taken for long-term chronic illnesses are more profitable than short-term antibiotics and antivirals
finding new drugs is not easy and is also costly, time consuming and a risky investment as there is no guarantee that a new drug will actually be suitable for use in humans
harder to find compounds that are toxic to viruses but safe for human cells
antivirals have only been developed since 1980s, in response to the HIV AIDS epidemic.
need to be taken soon after becoming infected to reduce symptoms and duration of a viral illness. making them useful during outbreaks to minimise spread.
treat viral infections by interfering with 'life' cycle by inhibiting their development, reducing their ability to bind to host cells or reproduce inside host cells, preventing it from leaving the host cells after it has multiplied and stimulating the host immune system
The World Health Organisation has launched a Global Action Plan on Antibiotic Resistance to limit the damage caused by this growing problem
antibiotic resistance is an even greater problem in developing countries due to misuse of antibiotics by unskilled practitioners, poor conditions etc.
superbugs: bacteria resistant to almost every available antibiotic. impossible to treat.
the development of antibiotic resistance in bacteria-due to misuse and overuse, is now reducing their effectiveness.
since mid-20th century (1940s), the use of antibiotics has hugely decreased the number of deaths due to bacterial infections and increase the average life expectancy.
'broad-spectrum' effective against a wide range of bacterial species. 'narrow-spectrum' effective against only a few species.
toxic to bacteria,killing them
Procedures to prevent the spread of disease
disease resistant animals and plants, increasing farming productivity, reducing pesticides
genetically modified infertile mosquitoes released to reduce number of vectors
genetically modified cattle to produce antibodies for passive vaccines
genetically engineering plants to produce vaccines that can be eaten
improving purity of vaccines by using genetically modified bacteria to produce antigens in active vaccines
community hygiene: water treatment, sewerage systems and treatment, rubbish collection and disposal, strict hygiene practices in health centres
personal hygiene: handwashing, safe sex,avoid sharing things
hygeine in food preparation: wearing gloves, cooking thoroughly, storing at correct temperature
household hygiene: keeping surfaces and utensils where microbes can proliferate clean.
causes environmental and health problems. e.g. leads to biological magnification affecting food chain and top predators and serious health problems in humans such as asthma.
can be applied by spraying, irrigration water,baiting,dipping or drenching
widely used to control vectors such as mosquitos
chemicals used to kill pests that affect the health of humans, animals and plants. effectiveness is decreasing due to pesticide resistance
e.g. Riverland and Tasmania free of Fruit flies
protects: farming industries, native plants and animals and health of human population
system of measures taken by authorities to prevent people from bringing materials that could be carrying pest or diseases into a country (AQIS)
detaining anyone arriving at the border if suspected of carrying an infectious disease
isolating diseased organisms
Public health campaigns
herd immunity is created when a very high proportion of the population is vaccinated. it protects those who can't be vaccinated. decreases the spread of disease.
e.g. campaigns aimed at increasing vaccination rates 'no jab,no pay'.
programs run by governments or public organisations to publicise health issues with the aim of reducing the incidence of disease by raising awareness and making people better informed
difficult and costly to produce requiring huge amounts of donated blood. New development of monoclonal antibodies in the lab.
release antibodies from an immune organism to fight the infection. Fast acting not long lasting and helpful for anyone who does not respond to immunisation or is immuno-deficient
release antigens into body to teach the immune system to recognise it and fight it producing memory cells. Contains weakened pathogens.
Factors affecting the spread of disease
increasing movement of of people due to tourism, trade ,migration and wars, the emergence of new diseases with capacity to infect enormous numbers of people due to low host resistance, possibility of bioterror attack deliberately releasing deadly pathogens, increasing numbers of antibiotic resistance.
how Virulent, robust (survival) and infectious a pathogen is. Characteristics, transmission, prevention or treatment and where they live.
climates that enhance spread of diseases (tropics), high population densities, poverty (economic),conflict (leading to refugees),high levels of tourism and trade and global warming
low resistance due poor living situation. overcrowded conditions, lack of clean water , proper sanitation or enough food e.g. Cholera epidemics
low resistance due to new pathogens (when pathogen crosses species border) creates epidemics. e.g. Flu epidemics
poor living conditions, limited access to medical care, high degree of contact with animals, local cultural practices facilitate in spread of disease or make it harder for authorities to control
melting of permafrost releasing pathogens that have been frozen e.g. anthrax outbreak in Siberia
global warming/climate change causing many diseases to spread from tropics to spread further
diseases are more common in tropical climates