Breast Milk/Malnutrition/Vaccines Flashcards
What structures form the gross anatomy of the breasts?
Nipple
Areola
Mammary Tissue
Supporting Connective Tissue (fat, lymph, blood, nerves)
What structures form the histological anatomy of the breast? Provide a brief description of their role.
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
How is breast development impacted by puberty and pregnancy?
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)
How is lactation controlled?
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
What psychological role does oxytocin and prolactin have for a mother and infant?
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’.
What components form breast milk?
Water
Protein (60-80% whey (lactalbumin))
Carbohydrates (40% lactose)
Fats (long-chain fatty acids (essential for brain development and fat-soluble vitamin absorption))
What constituents form breast milk but are not found in formula?
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))
What are important functions of the gut microbiome?
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)).
What is the name of the first milk produced by breasts, and what does it consist of?
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
What health related impacts does breast milk provide?
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)
What beneficial impacts does skin-to-skin have?
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
What is the correct positioning of a baby during feeding?
CHIN Close Head back Baby's head and body In line Nose-to-nipple starting position
How do rates of breast feeding differ based on socioeconomic income?
17% in low SE areas, and 97% in some high se areas.
Costs the global economy $302 billion a year
What percentage of women continue to breastfeed after 4 months?
34%
What percentage of babies receive breastmilk and what contributed to this?
81% as of 2010
UNICEF Baby Friendly Initiative helped to develop breastfeeding initiatives which promoted education and support for breastfeeding
What is the double burden of malnutrition?
Both obesity and underweight malnutrition existing side-by-side in the same community.
Underweight children are at increased risks of becoming obese.
What programs/strategies can be utilized to help fight the double burden of malnutrition?
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.
What is malnutrition?
Bad nutrition
Includes; undernutrition, vitamin/mineral deficiencies, obesity
How many children/elderly in the UK are impacted by food insecurity?
1 in 10 are living with an adult who has reported experiencing severe food insecurity
1 in 7 elderly live in extreme poverty
What are the different levels of underweight malnutrition?
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
What is obesity?
Overweight- BMI over 25
Obese- BMI over 30
What problems are associated with obesity?
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)
How do obesity levels differ for men and women in low income areas.
Obesity levels are higher in low se areas.
Obesity levels are much higher in women in low se areas, but lower in men.
What factors lead to obesity?
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
What are the two forms of stigma? Briefly explain each
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]
What is passive immunity?
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
What are pro’s and con’s to antibody preparations?
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
What antibody’s are first to respond to infection?
IgM first, then IgG
What are live vaccines? Give an example.
Attenuated strains which replicate in host.
Strong, long-lasting immunity.
MMR, BCG, Yellow Fever, rotavirus
What are inactivated vaccines? Give an example.
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.
What are some major differences in live vs inactivated vaccines?
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
What are the 4 ethical pillars of health?
Benefit to others
No Harm
Autonomy
Justice
What are some examples of vaccine preventable diseases caused by bacteria?
Pertussis- whooping cough Haemophilus influenza type b Meningococcal C Pneumococcal Disease Tuberculosis
What are some examples of vaccine preventable diseases caused by virus?
Polio Measles Mumps Rubella HPV Varicella Hep B Influenza
What are some examples of vaccine preventable diseases caused by toxins from bacteria?
Diphtheria
Tetanus
How has pertussis vaccination programs changed over time?
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)
What are the 6 goals of the global vaccine action plan?
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
Where is polio still endemic?
Pakistan and Afghanistan
Importation country is Syria
Nigeria is officially endemic, but on verge of being eliminated
Why are polio derived strains an issue in regards to eradication?
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
When referring to vaccines, what is “the switch”?
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
What are some targets for eradication/elimination?
Measles, Rubella, Yaws, Trachoma, Malaria, Guinea Worn (close, due to environmental changes), River Blindness, Lymphatic Filariasis
What are challenges to global immunisation?
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)
How do immunisation and vaccination differ?
Immunisation refers to vaccine induced immunity, AND transfer of antibodies/immunoglobulins (passive immunity)
What are some reasons for selective immunisation?
Travel, occupational risk, high risk groups, control outbreaks
How do eradication, elimination, and containment differ? Give examples.
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)
What are polysaccharide vaccines and conjugate vaccines and how do they differ?
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.
What are the non-antigen based components of a vaccine?
Adjuvant- chemicals added to improve response, like aluminium salts
Stabilisers
Trace Components- left over from manufacturing
Preservatives
Antibiotics
Why are there time intervals between vaccines, and how long is it typically?
Usually around 4 weeks
It allows each immune response to develop, and avoids immune interference
What is primary and secondary vaccine failure?
Primary- Fail to respond to first vaccine
Secondary- immunity wanes over time (mumps)
What are adverse events related to live and inactived vaccines?
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
What are the reproduction numbers in relation to infection transmission?
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
What is the herd immunity threshold calculation?
HIT = 1 - (1/R0)
How do hormones from the hypothalamus move to the pituitary?
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.
