Breast Milk/Malnutrition/Vaccines

Question 1

What structures form the gross anatomy of the breasts?

Answer 1

Nipple
Areola
Mammary Tissue
Supporting Connective Tissue (fat, lymph, blood, nerves)

Question 2

What structures form the histological anatomy of the breast? Provide a brief description of their role.

Answer 2

Montgomery’s Tubercles- secretes sebaceous fluid to lubricate nipple and attract infant
Lobes- 20 lobes containing alveoli
Alveoli- contain lactocytes surrounded by myoepithelium
Lactocytes- product milk
Myoepithelium- contract when oxytocin is sensed to push milk out of alveoli into lactiferous ducts
Lactiferous ducts- move milk from alveolus to nipple

Question 3

How is breast development impacted by puberty and pregnancy?

Answer 3

Puberty- Oestrogen promotes mammogenesis (ductal system development)
Pregnancy- Progesterone and Human Placental Lactogen enhance structures that will produce milk, and increase blood supply to breasts (increase nutrient supply for breast milk production)

Question 4

How is lactation controlled?

Answer 4

Suckling stimulates the posterior pituitary gland to secrete oxytocin which acts on the myoepithelium causing contraction and ejection of milk from alveoli (produced by lactocytes)
Suckling stimulates release of prolactin from anterior pituitary which stimulates the lactocytes to secrete milk for the next feed.
As milk builds up, there is feedback inhibition preventing the production of more milk, until suckling

Question 5

What psychological role does oxytocin and prolactin have for a mother and infant?

Answer 5

Produce feelings of calmness in both
Help the mother fall in love with infant and want to hold, stroke and protect him/her.
Keeping her infant close makes breastfeeding easier because it keeps the level of oxytocin in the mother’s bloodstream higher and the oxytocin reflex becomes conditioned over time, so that it becomes easier to ‘think it up’.

Question 6

What components form breast milk?

Answer 6

Water
Protein (60-80% whey (lactalbumin))
Carbohydrates (40% lactose)
Fats (long-chain fatty acids (essential for brain development and fat-soluble vitamin absorption))

Question 7

What constituents form breast milk but are not found in formula?

Answer 7

Growth factors (insulin-like and transforming growth factor, epidermal)
Stem cells
Immunoglobulins (IgA (essential for protecting gut-entry of pathogens), IgG/M/D
Leukocytes
Lactoferrin (binds iron making it unavailable to bacteria- good for preventing gastroenteritis)
Oligosaccharides (healthy gut- feeds microbiome)
Human-milk lipids (damages outer surface of some viruses)
IL-7 (linked to larger thymus (good for Ab production))

Question 8

What are important functions of the gut microbiome?

Answer 8

Producing Vitamin K, biotin and folate
Aiding development of the immune system
Converting oligosaccharides to short-chain fatty acids which provide energy sources for enterocytes
Binding to sites on the layer of cells lining the gut and providing a barrier that may prevent absorption of toxins.
Helps seal the immature gut of premature babies, preventing colonisation by pathogenic bacteria (preventing Necrotising Enterocolitis (NEC)).

Question 9

What is the name of the first milk produced by breasts, and what does it consist of?

Answer 9

Colostrum
Rich in protein, fat-soluble vitamins (A), mineral levels, mild purgative (laxative), high viral fragments and white cells, Igs and Abs, creates acidic environment, anti-inflammatory molecules and epidermal growth factor

Question 10

What health related impacts does breast milk provide?

Answer 10

Immune protection (vertical transmission, broncho-entero-mammary activation)
Promotes brain development (long-chain polyunsaturated fatty acids (docosahexaenoic acid) support development)
Promote gut maturation (Epidermal gf promotes healing, neuronal gf promote development of peristalsis, both reduce necrotizing enterocolitis)
Mothers health (protects against postpartum haemorrhage, postpartum depression, ovarian/breast cancers, heart disease and T2 diabetes)

Question 11

What beneficial impacts does skin-to-skin have?

Answer 11

Stimulates lactation
Helps with recognizing infant’s feeding cues
Counteracts adrenaline in baby helping to regulate heartbeat and breathing
Releases calming hormones in baby
Stimulates baby’s digestion
Helps with colonization of good bacteria in infant
Stimulates feeding behaviour in baby

Question 12

What is the correct positioning of a baby during feeding?

Answer 12

CHIN
Close
Head back
Baby's head and body In line
Nose-to-nipple starting position

Question 13

How do rates of breast feeding differ based on socioeconomic income?

Answer 13

17% in low SE areas, and 97% in some high se areas.

Costs the global economy $302 billion a year

Question 14

What percentage of women continue to breastfeed after 4 months?

Answer 14

34%

Question 15

What percentage of babies receive breastmilk and what contributed to this?

Answer 15

81% as of 2010
UNICEF Baby Friendly Initiative helped to develop breastfeeding initiatives which promoted education and support for breastfeeding

Question 16

What is the double burden of malnutrition?

Answer 16

Both obesity and underweight malnutrition existing side-by-side in the same community.
Underweight children are at increased risks of becoming obese.

Question 17

What programs/strategies can be utilized to help fight the double burden of malnutrition?

Answer 17

Exclusive breastfeeding up/past 2 years- increases nutrition for infant and increases calorie expenditure for adult.
Deliver nutrition to elderly people
Design under-nutrition programs in better ways
More political commitment and adequate sourcing, better data on vulnerable groups/policy/program implementation, better capacities to delivery policies and programs.

Question 18

What is malnutrition?

Answer 18

Bad nutrition

Includes; undernutrition, vitamin/mineral deficiencies, obesity

Question 19

How many children/elderly in the UK are impacted by food insecurity?

Answer 19

1 in 10 are living with an adult who has reported experiencing severe food insecurity
1 in 7 elderly live in extreme poverty

Question 20

What are the different levels of underweight malnutrition?

Answer 20

Severe- below 3 standard deviations for median weight for height, visible severe wasting, or presence of nutrition oedema
Moderate- Weight loss and 2-3 SD below median weight for height
Mild- Weight loss and 1-2 SD below median weight for height

Question 21

What is obesity?

Answer 21

Overweight- BMI over 25

Obese- BMI over 30

Question 22

What problems are associated with obesity?

Answer 22

Medical- diabetes, hypertension, CVD, etc.
Social- internal and external, stigma, body image, engagement,
Environmental- sick leave, treatment for consequences of obesity (estimated to rise to 31 billion a year if no action taken)

Question 23

How do obesity levels differ for men and women in low income areas.

Answer 23

Obesity levels are higher in low se areas.

Obesity levels are much higher in women in low se areas, but lower in men.

Question 24

What factors lead to obesity?

Answer 24

Genetic predisposition
Leptin and appetite control 
Insulin production and fat deposition
Individual diet and exercise levels 
Deprivation, learning disability, gender, race
Obesogenic environment
Sugar potentially
World trade patterns, economic growth, technological progress, consumerism

Question 25

What are the two forms of stigma? Briefly explain each

Answer 25

External stigma- the experience of being treated differently to other people
Internal stigma-the way a person feels about themselves [e.g. shame, fear of rejection, discrimination]

Question 26

What is passive immunity?

Answer 26

Provided protection at, or around the time of exposure to a given pathogen via transfer from one person/animal to another
Antibody preparations given to individuals at high risk, or IgA from pregnant/breastfeeding mother to child

Question 27

What are pro’s and con’s to antibody preparations?

Answer 27

Pro:
Rapid, Preventative, Can be given to those with vaccine contraindications
Cons:
Expensive, Potential adverse events, limited evidence for treatment of some pathogens, no lasting immunity

Question 28

What antibody’s are first to respond to infection?

Answer 28

IgM first, then IgG

Question 29

What are live vaccines? Give an example.

Answer 29

Attenuated strains which replicate in host.
Strong, long-lasting immunity.
MMR, BCG, Yellow Fever, rotavirus

Question 30

What are inactivated vaccines? Give an example.

Answer 30

Acellular/sub-unit vaccines (polysaccharide, conjugate, toxoid, recombinant vaccine).
Do not contain pathogen capable of replicating.
Can be used in those with weaker immune systems
Polio, rabies, pneumococcal, typhoid, tetanus, diphtheria, Men B, Hep B.

Question 31

What are some major differences in live vs inactivated vaccines?

Answer 31

Live:
Long-lasting, strong, can revert to virulence, poor stability
Inactivated:
Shorter immunity, adjuvant needed, can’t cause infection, stable, fewer contraindications, need several doses, local reactions common

Question 32

What are the 4 ethical pillars of health?

Answer 32

Benefit to others
No Harm
Autonomy
Justice

Question 33

What are some examples of vaccine preventable diseases caused by bacteria?

Answer 33

Pertussis- whooping cough
Haemophilus influenza type b
Meningococcal C
Pneumococcal Disease
Tuberculosis

Question 34

What are some examples of vaccine preventable diseases caused by virus?

Answer 34

Polio
Measles
Mumps
Rubella
HPV
Varicella
Hep B
Influenza

Question 35

What are some examples of vaccine preventable diseases caused by toxins from bacteria?

Answer 35

Diphtheria

Tetanus

Question 36

How has pertussis vaccination programs changed over time?

Answer 36

In 2012, they began giving vaccine to pregnant women in weeks 28-32
In 2016 it changed to allow women to get it from 16-32 weeks (allows for greater access to the vaccine, even though the antibody protection may not be as high in earlier weeks)

Question 37

What are the 6 goals of the global vaccine action plan?

Answer 37

90% coverage for DPT (stuck at 86%)
Measles eradicated from 4 WHO regions (UK region has experienced a come-back of measles)
Rubella Elimination
Maternal/Neonatal Tetanus Elimination 
Polio Eradication
Use of new of underutilized vaccines

Question 38

Where is polio still endemic?

Answer 38

Pakistan and Afghanistan
Importation country is Syria
Nigeria is officially endemic, but on verge of being eliminated

Question 39

Why are polio derived strains an issue in regards to eradication?

Answer 39

Vaccine derived strains- the live attenuated polio drops can revert to virulence. People excrete these virus parts in stool, which can cause infection.
The strains are now causing more infections than the wild-type

Question 40

When referring to vaccines, what is “the switch”?

Answer 40

Global switch from oral vaccine against polio strains 1-3, to oral vaccine with strains 1 and 3, as 2 had been eliminated.
Injected Inactivated Polio Vaccine still contains all 3 strains

Question 41

What are some targets for eradication/elimination?

Answer 41

Measles, Rubella, Yaws, Trachoma, Malaria, Guinea Worn (close, due to environmental changes), River Blindness, Lymphatic Filariasis

Question 42

What are challenges to global immunisation?

Answer 42

Funding, coverage, uptake
Surveillance
Different priorities, different vaccines (i.e. rotavirus in Africa)
Multiple agencies (Bill and Melinda Gates, UNICEF)
Suspicion and mistrust
Violence (war, civil unrest, targeted)

Question 43

How do immunisation and vaccination differ?

Answer 43

Immunisation refers to vaccine induced immunity, AND transfer of antibodies/immunoglobulins (passive immunity)

Question 44

What are some reasons for selective immunisation?

Answer 44

Travel, occupational risk, high risk groups, control outbreaks

Question 45

How do eradication, elimination, and containment differ? Give examples.

Answer 45

Eradication- disease and its causal agent have been removed worldwide (smallpox)
Elimination- Disease has been reduced to zero in defined geographical area (polio)
Containment- Point at which disease no longer constitutes a significant public health problem (HiB)

Question 46

What are polysaccharide vaccines and conjugate vaccines and how do they differ?

Answer 46

Polysaccharide: Inactivated subunit vaccine composed of long chains of sugar molecules that make up the surface capsule of certain bacteria. T Cell independent, less immunogenic in under 2 years, no booster response.
Conjugate is when polysaccharide is linked to a protein antigen (can include toxoids, like tetanus linked to polysaccharide). They have better immune response in under 2s.

Question 47

What are the non-antigen based components of a vaccine?

Answer 47

Adjuvant- chemicals added to improve response, like aluminium salts
Stabilisers
Trace Components- left over from manufacturing
Preservatives
Antibiotics

Question 48

Why are there time intervals between vaccines, and how long is it typically?

Answer 48

Usually around 4 weeks

It allows each immune response to develop, and avoids immune interference

Question 49

What is primary and secondary vaccine failure?

Answer 49

Primary- Fail to respond to first vaccine

Secondary- immunity wanes over time (mumps)

Question 50

What are adverse events related to live and inactived vaccines?

Answer 50

Live- reactions tend to mimic actual response cause by infection, and lessons with additional doses. Timing depends on time for pathogen to replicate
Inactivated- reactions increase with additional doses because reaction is to component of vaccine, not to the actual infection. Time generally within 48 hours of vaccine

Question 51

What are the reproduction numbers in relation to infection transmission?

Answer 51

R- How many people would typically be infected by person who is infected
R0- Number of people who would be infected with disease if infection was introduced to totally susceptible population. If greater than 1, epidemic is possible

Question 52

What is the herd immunity threshold calculation?

Answer 52

HIT = 1 - (1/R0)

Question 53

How do hormones from the hypothalamus move to the pituitary?

Answer 53

Hormones set to reach anterior pituitary will move through portal veins
Hormones (oxytocin and vasopressin) will move through axons where they’re stored in posterior pituitary until release.