infectious disease - prevention, treatment and control

Question 1

factors which help the spread of infectious diseases

Answer 1

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

Question 2

factors that can assist in minimising the spread of infectious diseases

Answer 2

Hygiene practices, both communal and personal

National and international quarantine programs

Vaccination, including passive and active immunity

Targeted public health campaigns

Question 3

personal hygiene

Answer 3

Frequent bathing

Handwashing with soap and water (or sanitiser)

Correct respiratory hygiene when coughing and sneezing

Question 4

types of Communal hygiene

Answer 4

Water purification; filtration, chlorination or boiling

Sewerage infrastructure

Question 5

types of Communal hygiene

Answer 5

Water purification; filtration, chlorination or boiling

Sewerage infrastructure

Question 6

types of food hygiene

Answer 6

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

Question 7

quarantine

Answer 7

A strict isolation imposed to prevent the spread of disease or unwanted animals or plants.
Quarantine prevents the entry and spread of diseases

Question 8

what is vaccination

Answer 8

Vaccination (or immunisation) is the process of making people resistant to infection caused by specific pathogens. They are very effective at preventing future infections.

Question 9

active immunity

Answer 9

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.

Question 10

passive immunity

Answer 10

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.

Question 11

3 examples of public health campaigns

Answer 11

The Grim Reaper v AIDS

HPV vaccination

Whooping cough vaccination

Question 12

what are pesticides

Answer 12

Pesticides (insecticides, herbicides, and fungicides) are chemicals used to prevent the spread of infectious animal and plant pathogens and also insect vectors.

Question 13

Insecticide control of malaria vector

Answer 13

The rapid generation turnover of most pathogens and insect resistance has led to widespread pesticide resistance.

Question 14

genetic engineering

Answer 14

Genetic engineering involves the modification of an organisms genome, for example by the insertion of a transgene.

Question 15

bt cotton

Answer 15

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.

Question 16

antiviral positives

Answer 16

Antivirals can be designed to target specific viral pathogens.

They can significantly improve the health outcomes and life expectancy of infected individuals.

Question 17

antiviral negatives

Answer 17

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.

Question 18

antibiotics positives

Answer 18

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.

Question 19

antibiotics negatives

Answer 19

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.

Question 20

epidemic definition

Answer 20

an outbreak of an infectious disease that spreads rapidly among individuals in a defined area or population at the same time.

Question 21

pandemic definition

Answer 21

the spread of a new disease across a continent or even worldwide.

Question 22

features of environmental management

Answer 22

Vaccination

Water supply

Food sources

Hygiene

Control population movement

Question 23

features of quarantine

Answer 23

Inspection

Regulation

Restriction of movement and

Enforced destruction of diseased organisms

Question 24

herd immunity

Answer 24

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.

Question 25

whooping cough

Answer 25

Whooping cough is a highly contagious respiratory illness caused by the bacterial pathogen Bordetella pertussis.

It is a notifiable disease in all of Australia.

Question 26

dengue fever in south east asia

Answer 26

Dengue fever is a mosquito-borne viral infection found in tropical and subtropical climates worldwide.

potentially lethal (severe dengue)

Question 27

historical strategies to control spread of disease

Answer 27

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.

Question 28

malaria history

Answer 28

two ancient (13th century) Italian words “mal” and “aria” = “bad air.”

The disease was associated with the swamps and marshlands of Rome.

Question 28

miasma origin

Answer 28

ancient Greece (400BC).

Question 29

Malaria pre-etiology

Answer 29

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.

Question 30

Malaria post-etiology

Answer 30

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.

Question 31

cholera background

Answer 31

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.

Question 32

where did the first cholera pandemic originate

Answer 32

The first cholera pandemic (1817-1823) originated in India and spread via trade routes across to South East Asia, African and the Middle East.

Question 33

impact of germ theory by louis pasteur

Answer 33

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.

Question 34

Tea tree oil (Melaleuca alternifolia)

Answer 34

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.

Question 35

Eucalyptus oil (Eucalyptus sp.)

Answer 35

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.

Question 36

Kakadu plum (Terminalia ferdinandiana)

Answer 36

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.

Question 37

Biopiracy definition

Answer 37

The act by which a commercial business appropriates traditional knowledge without recognition or benefit-sharing.