infectious disease - prevention, treatment and control Flashcards
factors which help the spread of infectious diseases
Environmental change and agricultural development
Providing ease of dissemination of organisms and/or resistance, e.g. Introduced species
Breakdown of public health programs, e.g. inability to cope with population growth
Alterations in human behaviour, e.g. urbanisation
factors that can assist in minimising the spread of infectious diseases
Hygiene practices, both communal and personal
National and international quarantine programs
Vaccination, including passive and active immunity
Targeted public health campaigns
personal hygiene
Frequent bathing
Handwashing with soap and water (or sanitiser)
Correct respiratory hygiene when coughing and sneezing
types of Communal hygiene
Water purification; filtration, chlorination or boiling
Sewerage infrastructure
types of Communal hygiene
Water purification; filtration, chlorination or boiling
Sewerage infrastructure
types of food hygiene
Keeping raw and cooked foods separate
Cooking foods for the appropriate time and at the appropriate temperature
Storing food at recommended temperature
Using clean water for cooking
quarantine
A strict isolation imposed to prevent the spread of disease or unwanted animals or plants.
Quarantine prevents the entry and spread of diseases
what is vaccination
Vaccination (or immunisation) is the process of making people resistant to infection caused by specific pathogens. They are very effective at preventing future infections.
active immunity
The vaccine contains a live-attenuated or inactivated version of the pathogen which leads to no symptoms of the disease.
This leads to the production of antibodies and T and B memory cells specific to that antigen providing long-term protection from the disease.
passive immunity
Involves the injection of antibodies into an individual. The antibodies are produced in, and then isolated from other organisms.
It by passes the immune system and provides immediate protection. However, no memory cells are produced and protection is therefore only short-term. An example is the Tetanus vaccine.
3 examples of public health campaigns
The Grim Reaper v AIDS
HPV vaccination
Whooping cough vaccination
what are pesticides
Pesticides (insecticides, herbicides, and fungicides) are chemicals used to prevent the spread of infectious animal and plant pathogens and also insect vectors.
Insecticide control of malaria vector
The rapid generation turnover of most pathogens and insect resistance has led to widespread pesticide resistance.
genetic engineering
Genetic engineering involves the modification of an organisms genome, for example by the insertion of a transgene.
bt cotton
The cotton plants have had a gene from a soil bacteria, Bacillus thuringiensis (Bt) inserted into its genome.
Any insect that attempt to eat the cotton plants will ingest the toxin and die.
antiviral positives
Antivirals can be designed to target specific viral pathogens.
They can significantly improve the health outcomes and life expectancy of infected individuals.
antiviral negatives
Drugs used to target a virus therefore often cause harm to the host cell
high mutation rates of viruses→ drug-resistance.
Pharmaceutical companies have a monopoly on the market and this is reflected in the drugs cost.
antibiotics positives
200 million lives have been directly saved from antibiotics.
Due to different cell structures, e.g. cell wall, bacteria are more easily targeted than viruses.
antibiotics negatives
Antibiotics only work on bacterial infections.
Misuse and overuse have led to multiple examples of antibiotic resistance.
People can be allergic to antibiotics.
There can be side effects, including diarrhea, nausea and upset stomach.
epidemic definition
an outbreak of an infectious disease that spreads rapidly among individuals in a defined area or population at the same time.
pandemic definition
the spread of a new disease across a continent or even worldwide.
features of environmental management
Vaccination
Water supply
Food sources
Hygiene
Control population movement
features of quarantine
Inspection
Regulation
Restriction of movement and
Enforced destruction of diseased organisms
herd immunity
When an estimated 95% of a population is vaccinated (herd immunity) against a disease there is less of the disease in the community, which makes it harder for the disease to spread.
whooping cough
Whooping cough is a highly contagious respiratory illness caused by the bacterial pathogen Bordetella pertussis.
It is a notifiable disease in all of Australia.
dengue fever in south east asia
Dengue fever is a mosquito-borne viral infection found in tropical and subtropical climates worldwide.
potentially lethal (severe dengue)
historical strategies to control spread of disease
Chinese and Hebrews were advocating cleanliness in food, water and personal hygiene
Chinese deduced a connection between water contaminated by faeces and gastro-intestinal diseases.
Hebrews are believed to have made a connection between the symptoms of infection by tapeworm and eating undercooked pork.
malaria history
two ancient (13th century) Italian words “mal” and “aria” = “bad air.”
The disease was associated with the swamps and marshlands of Rome.
miasma origin
ancient Greece (400BC).
Malaria pre-etiology
around 170BC, the herbal remedy Qing-hao was used to treat fever episodes (believed to be caused by malaria).
The active ingredient of Qing-hao, known as artemisinin, was isolated by Chinese scientists in 1972.
During the Middle Ages (5th-15th century), treatments for malaria included blood-letting, limb amputations and trepanning.
In 1737, while in Ecuador, the French explorer Charles Marie de La Condamine found that the bark of the Cinchona tree could be used to treat malaria.
In 1820, French researchers Pierre Pelletier and Joseph Cavento first isolated quinine, the active ingredient, from the Cinchona tree.
Malaria post-etiology
In 1897 Britain’s Sir Ronald Ross, protozoan, Plasmodium spp., caused malaria and were transmitted by mosquitoes.
In 1934 chloroquine, the first synthetic drug used to prevent malaria, was developed by the Italian scientist Hans Andersag.
DDT was used from 1939 onwards to kill the Anopheles mosquito vector.
successful until the mosquitoes developed resistance to the DDT.
cholera background
The infection usually causes mild diarrhoea. However, in 10% of cases, severe watery diarrhoea and vomiting can occur which causes extreme dehydration and even death.
disease is easily spread when sewage and drinking water supplies come in contact.
The greatest risk occurs in overpopulated communities and refugee settings which lack access to clean drinking water and have poor sanitation.
where did the first cholera pandemic originate
The first cholera pandemic (1817-1823) originated in India and spread via trade routes across to South East Asia, African and the Middle East.
impact of germ theory by louis pasteur
germ theory by Louis Pasteur and Robert Koch
- From the 1880s it was known that each disease (effect) was caused by a specific pathogen (cause).
As a result, specific preventive and control measures can be taken to avoid infection. In addition with the etiology known, predictive modelling can be used to determine possible outbreaks.
Tea tree oil (Melaleuca alternifolia)
Indigenous Australians use various parts of the tree to create a paste that contains the oil.
It is used as an antiseptic to treat wounds and infections.
Eucalyptus oil (Eucalyptus sp.)
There are over 700 Eucalyptus species across Australia.
Indigenous Australians have long used the oils for their natural antimicrobial and antiseptic properties.
Pharmaceutical companies have determined the active ingredient to be 1.8-cineole. Now used commercially in mouthwash, throat lozenges and cough suppressants.
Kakadu plum (Terminalia ferdinandiana)
Endemic to the Northern Territory and Western Australia, the Kakadu plum
is the world’s richest source of vitamin C, with 50 times more vitamin C than oranges. Vitamin C is essential for the growth and repair of all tissues.
Biopiracy definition
The act by which a commercial business appropriates traditional knowledge without recognition or benefit-sharing.
