Screening for infectious disease in pregnancy Flashcards
Name the two types of screening
Universal- everybody is screened
selected- only people who have risk factors
what is screening
process of identifying apparently healthy people who may be at increased risk of a disease or condition
in pregnacy screening looks at the unborn baby- to see any defects eg downs
name three screenings that pregnant women go through
HIV
hepatitis B
syphilis
when was HIV screening introduced for pregnant women,
1999, 2000 all pregnant women where offered the screening, 90% uptake by 2002
what is HIV
a retro-virus, which, if left untreated, leads to immunosuppression and eventually to acquired immune deficiency syndrome (AIDS)
How is HIV transmitted
it is present in body fluids such as blood, semen, vaginal secretions and breast milk,
transmitted through unprotected sexual intercourse, direct contact with the blood of an infected person, sharing infected needles, from mother to child during pregnancy, at birth or when breast feeding
what are CD4 cells
T-helper cells, are white blood cells which plays an essential part in the human immune system
Made in the spleen, lymph nodes and thymus gland
Role of CD4 cells
to detect pathogens and send signalsto other types of immune cells, including CD8 killer cells, to destroy the infectious particles
How dose HIV effect the CD4 cells
When HIV enters the body it targets and invades the CD4 cells in the blood.
Once inside the CD4 cell the virus begins a the replication process to produce new HIV virons. When completed, the new virons break through the cell wall and out into the bloodstream, destroying the CD4 cell.
this process is reprted to allow the virus to spread
Normal CD4 cell count in a normal person compared to someone with HIV
Normal- between 500 and 1,500 cells per ml of blood
HIV- this number falls, and can if it falls to a level where the immune system is no longer able to function adequately and the person becomes susceptible to opportunistic infections and HIV related cancers
How can HIV be transferred to the child during pregnancy
Mother-to-child vertical transmission, but this is rare, in an untreated mother this is 25%, in a treated mother it is 0.5% of the child being born with HIV
Name a way in which a child can contract HIV from the mother after birth
From breastfeeding, thus formula is recommend for mothers with HIV
when was hep B screening introduced in the UK
1988 - selected screening
1999- universal screening
programme fully implemented in 2000
What is hepatitis B (Hep B)
an infectious inflammatory illness of the liver caused by the hepatitis B virus, two phase, acute and chronic,
it is called a silent disease and is easy to pass on
name to the phases of hep B
acute and chronic
what dose having high CD4 cell count mean
high immunity
How dose Hep B replicate
enters a liver host cell, alters it’s DNA and replicates, this condition is easy to pass and is nicknames the silent disease
what dose Hep b cause
inflammation of the liver
what is acute Hep B
new infection, 1-4 months symptoms- 90% will clear on it’s own after a few weeks- this gives the persons an immunity to re-infection
How are P women with HIV advised to help it not spread to the child
only use formula milk-
and antiretroviral therapy- most common therapy used in P women
what is chronic hep B
infection that has not cleared after 6 months- person becomes a lifelong carrier, 20% will develop cirrhosis (scarring of the liver which increases cancer risk
issues are worse if contracted as a baby then an adult
what is cirrhosis
issue of chronic Hep B- scarring of the liver which increases cancer risk
how is Hep B transmitted
through all body fluids perinal transmission( m to child)
is Hep b preventable
yes by vax
what are some of the signs and symptoms of hep B
Fever, fatigue, pain loss of appitie nausa, vomiting, pale and light stools dark yrine
is hep b a greater risk at a younger age
yes. 90% of infected infents will be chronic
50% 1-5 becme Chronic
5-20% 19+ will be C
is the risk increased if the mother has hep B
Yes if the mother has hep B then the risk is increased, but it depends on the mothers stauts, with no intervention 90% of B will be born with Hep compared to 10% with M with hep
what is perianal transmission
can result in an acute or chronic infection,Without vaccination, 95% will have a sub-clinical infection (C carriers for life), 40% risk of death from cirrhosis/cancer
can be perianal transmission be halted
yes by a vax at the correct time,
The mode of delivery and breastfeeding does not affect mother to child transmission if the baby receives appropriate management
what is syphilis
infectious disease, caused by bacteria,
transmitted through sexual contact, M to C in fetus and delivey,
4 stages
what are the 4 stages of Sy
primary and secondary where a person is symptomatic and highly infectious
latent- infection found on lower levels
tertiary where syphilis re-activates and serious health complications are common
what stage of Sy presents the highest risk in P
primary and secondary- 70-100% risk
Latent- 40%
Late-10%
most risk in first two stages
what issues can Sy cause
miscarriage, still birth, birth defects eg hearing loss and neurological impairment
babies born with congincal SY when do they display symptoms and what can it cause
symptoms at w5, if untreated it can cause neurological impairment eg hearing loss
what are the 3 reasons for a positive screening
current infection
past sy infection
false positive due to other infection eg treponmal
what is the treatment for Sy
P women with a positive test should be referred to fetal medicine by 26 weeks
name some of the disease that are not usally screened (can be if at high risk)
rubella susceptibility • chlamydia • cytomegalovirus • group B streptococcus • hepatitis C • toxoplasmosis • chickenpox (varicella susceptibility) • parvovirus B19
what is Rubella
not common disease, viral infection, can be dorment, transmitted via droplets from coughing
50% of infected People will show no symptoms
what is congenital rubella syndrome
very rare, occurs when the virus that causes rubella disrupts the development of an unborn baby, depending on how early in P it was contracted depends on the severity of the birth defects
How can rubella effect p women
it can be passed to the F without any issues, But if a woman gets rubella shortly before getting pregnant or during the first three months of pregnancy, it is very likely to result in miscarriage or congenital anomalies known as congenital rubella syndrome (CRS).
when is CRS greater risk
The earlier in the pregnancy, the greater the risk
infection if the first 10w- risk as high as 90% and can causes many B defects
11-16w- 10-20%- few B defects
17-20w- very rare- hearing loss
what is Cytomegalovirus
common virus-50% of Uk pop have it in their lifetimes
flu like symptoms- can be dormant
40% of pw are suceptablie at time pf p
main risk is when caught the first time
40% of b being infected- 90% of these show no Symptomes at birth
how is Cytomegalovirus transmitted
only passed when active
through body fluid, close contact
Pregnant women can pass an ‘active’ CMV infection on to their unborn baby- usally from children saliva
how can cytomegalovirus be active
you catch the virus for the first time – young children often get CMV for the first time at nursery
•the virus has ‘re-activated’ – because you have a weakened immune system
•you’ve been re-infected – with a different type (strain) of CMV
what are some of the symptoms of Cytomegalovirus
hearing issues small head size, small size in genral seizures jondice enlarged livers + spleen pneumonia •a rash of small, purplish spots low birth weight
how can Cytomegalovirus be prevented
washing hands
avoid face kissing
what is Toxoplasmosis
infection caused by parasites which affect warm bodied animals,
can be caught by eating raw meat, unpasteurised milk chesses, unwashed F+V
infection In P can causes damage to the B
Once caught your are immune for life, no symptoms
only 4 in 10 of such infections will pass to the baby
what issues can Toxoplasmosis
still birth, miss-carriage, damage to B brain and other organs,
How can Toxoplasmosis be passed in P
through the placenta,
infected matter entering human body fluids- lambing
transplanted organs, blood ect
through inhaling the parasite eggs
