Containment - lecture 4 - blood borne diseases

sanquin

• non profit

• monopoly of Nl blood bank

blood borne infections

• classical BBIs

  • syphillis

  • bacterial contaminaton (platelets)

  • silent yersinia bacteremia (coli bacteria may linger in the blood and end up in the blood donation).

• emerging BBIs (threats)

  • arboviruses → dengue, west nile virus

  • zooonotic → vCJD, Q fever, HEV

• irrelevant BBIs

  • GBV-C

  • tenoviruses

  • usutuviruses

what do the impact of BBIs depend on

• prevalence among donors

• transmissibility 

• severity of disease in recipient 

transmission routes of viruses

hepC

• human pathogen with exclusive parenteral transmission via blood 

• hepC → can cure with taking pills for few weeks

• pamela anderson had it → shared needle with husband Tommy Lee

• hepB and HIV can only be supressed not cured

• silent killer, can walk around for years and then get sick (liver) and die

BBIs, infectious materials

• green can be sterilized → immunoglobulins etc.

• needles → in hospital, drugs etc. 

• you&me → birth, unprotected sex, tattoos etc. 

new versus old donors

• new donor represents the prevalence of an infection (no idea when the infection was acquired)

• repeat donor represents the incidence → new infections acquired.

window donation

• donor already has the infection but the test does not pick it up yet

• missed early infection

transfusion recipients

• one very clear time where transfusion saves life → pregnancy, when women lose a lot of blood during child birth can be saved with transfusion

prevention of transmission via blood

1. donor selection

2. first visit donot; testing only, no donation 

3. screening of each donation 

4. inactivation / removal of agents

5. restrictive use of blood 

6. monitoring of emerging infections

7. recipient tracing (treatment etc.) 

screening of each donation

serology versus PCR for picking up infections

• PCR only picks up a few cases (but is used because it detects certain diseases earlier (window detecting))

• but only picked up 1 HIV case → still is done.

• The benchmark to do a medical measure in the Netherlands in 80000 euros. However it costs 13 million to do the PCR measure of HIV. Still do it to assure the trust of all the patients (emotion management).

hep.E

• all piglets get hep.E virus → 1:10 is viremic at time of slaughter

• alot of hep.E virus in our food (leverworst)

• hep.E is confusing → 2 different kinds of diseases

  • tropical acute one, genotype 1 and 2

    • 20% fatality

  • western silent one, genotype 3

    • no disease

    • except in organ, stem cell patients, they can not clear the virus. → rapid liver cirrhosis and liver failure in a few years.

    • free vaccination for the dangerous Hep.E

why are there Mpox outbreaks

• 1980 small pox were eradicated. now no more pox vaccination.

• today no more cross reactive immunity in 70% of the world !!

• so pox has started to

• chickenpox is a herpesvirus → noting to do with pox!!

• symptoms of pox → rash, fever, sore throat headache

Mpox complications

• secondary bacterial infections can occur

• skin lesions

• pneumonia

• infection cornea → blindness

Mpox transmission

• no idea if it is transfusion transmissible → probably is according to Hans Zaaij

• close contact → including within a household 

• skin to skin, outh to moith, mouth to skin, kissing, sex, touching face to face 

• via contaminated objects (linnen, towel) 

• to fetur or newborn 

• animal to human 

mosquito borne infections

• on the rise

• 80% of mosquito infections go asymptomatic

• tiger mosquito on the rise → dengue, zika, chikungunya

  • often found in old pig cellars (old manure, rotting cellars).

  • in the Netherlands RIVM will kill all tiger mosquitos when found in a village.

  • dengue now endemic in certain areas in europe (italy, france, spain).

• ordinary house mosquito → west nile virus, USUV

• sheep tick → TBE, lyme

covid - why is the rainbow reversed

• old people vaccinated earlier (but the very first, young nurses)

• and the other piek shows the omicron variant. Young people were going out more, so they got infected first.

• very first red line is the young female health care workers that got the first vaccine.

re-infection

• the level of core antibodies (in blood donors) was used as an indicator of re-infection

• also the water in riool wateringszuiverings installaties is checked each day for core antibodies.