infectious diseases

Question 1

disease

Answer 1

an illness or disorder of the body or mind that leads to poor health, each associated with a set of signs and symptoms.

Question 2

infectious disease

Answer 2

disease caused by pathogens

Question 3

non-infectious diseases

Answer 3

disease not caused by pathogens. including genetic disease, cardiovascular, deficiency and mental diseases.

Question 4

ENDEMIC

Answer 4

a disease that is permanent in a particular region or popuation

Question 5

epidemic

Answer 5

a disease that appears suddenly and spreads rapidly across a population/area

Question 6

pandemic

Answer 6

an epidemic that spreads wider, as far as international

Question 7

incidence

Answer 7

the number of people who are diagnosed within a certain time period

Question 8

prevalence

Answer 8

the number of people with the specific disease at any one time

Question 9

mortality

Answer 9

the number of people who die of the disease.

Question 10

retrovirus

Answer 10

a virus that reverse transcribes RNA into DNA within the host chromosomes using the enzyme reverse transcriptase, allowing the integration of the retroviral dna into the human dna

Question 11

t-helper cells

Answer 11

white blood cells produced by the body to activate the immune system in response to a pathogen

Question 12

HIV modes of transmission

Answer 12

semen/vaginal fluid during sex
blood
vertical

Question 13

HIV global distribution

Answer 13

worldwide, particularly Africa and SE Asia

Question 14

incubation period

Answer 14

few weeks up to 10 years

Question 15

site of pathogen action

Answer 15

T-helper lymphocytes, macrophages, brain cells

Question 16

clinical features of HIV

Answer 16

flu-like symptoms and then nothing.

weakens immune system to pneumonia, TB, dementia, vomiting etc

Question 17

diagnosis of HIV

Answer 17

testing blood, saliva, urine for HIV antibodies

Question 18

HIV treatment

Answer 18

drug combination, interrupting reverse transcription of virus
AZT + 2 protease inhibitors)

Question 19

why hasn’t a HIV vaccine been invented yet?

Answer 19

because continually changes antigens

Question 20

prevention of HIV

Answer 20

encouragement of male circumcision/faithfulness
education on cause and effects of infection
free provision of barrier contraceptive methods and sterile needles
screen blood from donors

Question 21

control of HIV

Answer 21

contact tracing
funding of testing/drug supply
drug therapy
vaccine research
bottle-feed HIV mother's children

Question 22

Tuberculosis

Answer 22

mycobacterium tuberculosis

mycobacterium bovis

Question 23

TB modes of transmission

Answer 23

mycobacterium tuberculosis is spread by droplets in the air when an infected person coughs
m bovis via uncooked meat and unpasteurised milk (originally given to cows by badgers)

Question 24

global distribution of TB

Answer 24

worldwide

Question 25

incubation period

Answer 25

few weeks to several years

Question 26

site of action

Answer 26

primary infection in lungs, secondary in lymph nodes, bones and gut

Question 27

clinical features of TB

Answer 27

racking cough, coughing blood, chest pain, shortness of breath, fever, sweating, weight loss

Question 28

diagnosis of TB

Answer 28

sputum examination, chest x ray,

Question 29

problems w TB prevention

Answer 29

many show no symptoms until your immune system is compromised. bacteria have lipid-rich walls, preventing them from drying out so that they last long prevalent in developing countries w poorer living conditions (overcrowded and ill-ventilated immigration has brought back to UK strains have developed resistance to the drugs, further increased by partial treatment

Question 30

prevention of TB

Answer 30

``` streptomycin antibiotics contact tracing patient isolation BCG vaccine combination of 4 drugs ```

Question 31

malaria

Answer 31

plasmodium malariae protoctist

Question 32

process of malaria vector transmission

Answer 32

female anopheles mosquito takes a blood meal from an infected person (to gain protein to lay eggs), taking pathogen gametes with it, before they fuse in gut to form infective stages which are passed on through the salivary glands with the anticoagulant, multiplying in an uninfected person's bloodstream

Question 33

methods of transmission of malaria

Answer 33

vector of female anopheles mosquito, blood transfusions, unsterile needles, vertically

Question 34

malaria global distribution

Answer 34

tropics and subtropics

Question 35

incubation period malaria

Answer 35

one week to a year

Question 36

malaria site of action

Answer 36

liver, red blood cells, brain

Question 37

malaria clinical features

Answer 37

vomiting, nausea, fever, anaemia, muscle pain, shivering, sweating, enlarged spleen

Question 38

malaria diagnosis

Answer 38

blood examination/ dipstick test

Question 39

malaria treatment

Answer 39

anti-malarial drugs acting as prophylactics chloroquine prevents protein synthesis and so parasitic spread proguanil inhibits sexual reproduction of plasmodium

Question 40

problems w malaria treatment

Answer 40

``` drug-resistance insecticide resistance expensive loss of immunity made villages more vulnerable migration of people climate change vaccine development difficulty insecticides mess w food chain, having knock-on effects on wildlife ```

Question 41

prevention of malaria

Answer 41

reduction in numbers of mosquitoes via oil spreading, draining ditches, biological control, fish stockponds, BT toxin, prevention of biting via mosquito nets sprayed w insecticides/ lack of skin exposure

Question 42

cholera

Answer 42

bacterium vibrio cholerae

Question 43

transmission of cholera

Answer 43

food/water borne | acquired in faeces contaminated water sources, fly-contaminated food, raw shellfish

Question 44

cholera incubation

Answer 44

2 hours to five days

Question 45

cholera site of action

Answer 45

small intestine walls | multiplies and attaches itself to epithelial membrane before releasing choleragen toxin, triggering ion and water loss

Question 46

cholera clinical features

Answer 46

severe diarrhoea, vomiting, fever, dehydration and weakness

Question 47

cholera diagnosis

Answer 47

faeces analysis

Question 48

cholera global distribution

Answer 48

endemic in Africa, India, Pakistan, Bangladesh, central/south America

Question 49

cholera treatment

Answer 49

oral rehydration therapy IV glucose drinks enable further absorption of ions into gut fluid intake matching fluid loss so as to maintain osmotic balance

Question 50

choleragen structure

Answer 50

2 protein complex (A sub-unit and 5 B sub-units). B is the binding protein which attaches the complex to a glycolipid on the cell surface membrane. A subunit is the enzyme that activates other membrane enzymes, causing the secretion of chloride ions into the gut lumen and inhibits sodium ion uptake

Question 51

cholera prevention

Answer 51

irrigation of vegetables w clean water and improvement of sanitation vaccine is short-term and ineffective

Question 52

MEASLES

Answer 52

retrovirus called morbillivirus

Question 53

measles transmission

Answer 53

droplets when infected sneezes/coughs

Question 54

measles incubation

Answer 54

10-14 days before rash appear and fever develops

Question 55

measles site

Answer 55

respiratory mucous membranes, lymph glands, upper-respiratory tract

Question 56

measles clinical features

Answer 56

red and light-sensitive eyes, fever, rash, white spots in mouth and throat can lead to pneumonia, encephalitis, hepatitis or blindness

Question 57

measles treatment

Answer 57

pain and fever reducing medication anti-viral medication if complications occur bed-rest medicine

Question 58

measles distribution

Answer 58

worldwide

Question 59

measles prevention

Answer 59

prior vaccine (MMR vaccine comprised of 3 attenuated strains and later boosters)