It's been a while.
Been studying anatomy and physiology for a while now. College really takes away all your time..
Either way, I'm working on a PBL assignment at the moment, and I figured I might as well put it online.
Although it only deals with the Human Papillomavirus(HPV) and the Dutch's way of dealing with immunization, it might just cover some information you might need for whatever assignment.
Roleplay situation: Aside from studying Health & Life Sciences, I also happen to work at a consulting bureau. I'm visiting some kid named Bram, whose parents don't have their children vaccinated for religious reasons. Their kid has a nasty cough, which sounds achingly similar to a dog's barking.
After I'm done visiting the family, I wonder whether my little sister should get a HPV shot or not..
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| Proof of vaccination |
How do vaccinations work?
Vaccination prevents severe disease by exposing the body to parts of a pathogen, live pathogens, or inactivated pathogens.
Simply said, there are 3 different kind of vaccines:
1. Killed/inactivated virus vaccines - containing pathogen particles or pathogens which have been killed or inactivated, and are therefore unable to replicate inside the human body, and they're also unable to cause diseases.
2. Live-attenuated vaccines - consists of live viruses that have mutated and are generally no longer pathogenic to our species. There are only few live-attenuated bacterial vaccines available.
3. Subunit vaccines - Consist of surface antigens of certain pathogens.
All three kinds work through activating the immune system by 'infecting the body'. This infection, however, is relatively harmless compared to a real infection of live pathogens. The body reacts to the components in the vaccines by setting up an immune response, and it gains memory cells(white blood cells which react to the same pathogens if you happen to catch the same disease again) during the process, allowing your body to eliminate the pathogens during subsequent infections without so much of a hassle.
You could compare vaccinations to practice dummy fights, during which you practice moves so that you know what to do during a real fight.[1]
Which vaccinations are given to Dutch children, and at what age? What about other kids? Why would the Dutch government recommend vaccination against certain diseases?
The National Immunization Programme (NIP) was started in 1957, and back then, it only offered DTP (Diphteria, Tetanus, Poliomyelitis) and Inactivated Polio Vaccine (IPV). [2]
Nowadays, vaccination against measles, mumps, rubella, Haemophilus influenzae type b, Meningococcal C disease, pneumococcal disease, hepatitis B (for high-risk groups only) and Human papillomavirus (given to girls only) is included in the programme. [3]
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| Dutch vaccination programme |
2, 3, 4, (11) months: Diphtheria, Whooping cough, Tetanus, Poliomyelitis and Pneumococcal disease
14 months: Mumps, Measles, Rubella, Meningococcal disease C
Age 4: Diphtheria, Whooping Cough, Tetanus, Poliomyelitis
Age 9: Diphtheria, Tetanus, Poliomyelitis, Mumps, Measles, Rubella
Age 12~13: Human papillomavirus (girls only)
These diseases were included in the NIP because they claimed the lives of many children or because they otherwise had the potential to cause severe disease before vaccination against these pathogens was started. [3]
Vaccinatiegraad - the amount of people vaccinated per community (in percentages)
Children age 2:
Diphtheria, Whooping Cough, Tetanus, Poliomyelitis: Generally >95%, 95.4% average
Haemophilus influenzae type b: Generally >95%, 96% average
Mumps, Measles, Rubella: Generally >95%, 95.9% average
Meningococcal disease C: Generally >95%, 95.9% average
Pneumococcal disease: Generally >95%, 94.8% average
Hepatitis B virus, only for children whose parents are from Hep B endemic countries: Generally >95%, 94.3% average
Children age 5:
Diphtheria, Whooping cough, Tetanus, Poliomyelitis: Generally >90%, 92.3% average
Children age 10:
Diphtheria, Tetanus, Poliomyelitis: Generally >90%, 93% average
Mumps, Measles, Rubella: Generally >90%, 92.6% average
Adolescent girls:
Human papillomavirus: 58.5% got 3 out of 3 vaccinations.[4]
Difference in amount of people vaccinated, per region
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| Amount of newborns vaccinated against Diphtheria, Whooping cough, Tetanus and Poliomyelitis in 2012 |
The mid- and southern regions of the Netherlands show less promising numbers: some areas show a count of less than 80%.
In communities with a percentage of <80, religion or lifestyle are the main reasons to blame for the disappointing numbers. In these groups, minor epidemics could take place >_> [4]
Reasons against vaccination
- Anti-vaccine movements
- Religion
- Needle phobia
- Risk of live-attenuated vaccine components mutating back into their former disease-causing state, [1]
- Side-effects
- Suspicion towards pharmaceutical companies or the government
- Lack of education
Although the Dutch government doesn't force anyone to have their children vaccinated, making vaccinations obligatory would raise the numbers closer to 100%. Some people will always try to dodge obligations, so we'll never fully reach 100%, but 99.99% would be fine as well.
Based on the symptoms of the 18-mo Bram, what kind of disease is he suffering from?
Whooping cough, caused by Bordetella pertussis.[5]
Prevalence of whooping cough in the Netherlands (2012) and changes in the vaccination against whooping cough since the nineties
Pertussis seems to occur regularly, with an epidemic every 3 years or so. More and more adults seem to contract some sort of pertussis. Morbidity is highest among unvaccinated children.[2]
The total number of people contracting pertussis this year was 13436 as of October 31st, 2012.[7]
The introduction of a pre-school booster vaccination (autumn 2001) for children aged 4 with an acellular vaccine caused a significant decrease in the incidence of pertussis among children.[2]
Treating pertussis
Antibiotics may be given, although studies suggest that they do not work as well against whooping cough. As whooping cough is easily transmitted to others, Bram should be isolated from other children, until his disease clears. Coughing and sneezing into a napkin and frequent washing of hands will lower the risk of it spreading to others.[5][6]
What is HPV, and what does it cause?
HPV - Human Papillomavirus is a virus, causing benign genital warts. Some strains can cause lesions and cervical cancer.[7]
Which vaccines against HPV are available, and what's the difference between them?
There are two different vaccines against HPV: Prophylactic (preventive) vaccines and therapeutic vaccines.
Prophylactic vaccination protects against acquisition of the virus and has so far shown the most promise. Therapeutic vaccines are used to treat infected individuals.[7]
Target groups for HPV vaccinations
HPV vaccines are given to 13yo girls, as they're generally not sexually active, yet. Therefore, they're unlikely to have caught HPV. The vaccine works best when you haven't been in contact with HPV yet.[8]
Pros and Cons of vaccination against HPV
Individual Pros: Protects the girl against several HPV strains
Individual Cons: Side-effects may occur. It may also give girls a false sense of security. The HPV vaccine only provides immunity against several HPV strains, but not against the whole set.
Population Pros: The population as a whole will suffer less infections. This includes males.
Population Cons: The HPV vaccine only provides immunity against several HPV strains, but not against the whole set.[10]
How many cases of cervical cancer and how many deaths could be prevented?
When at least 85% of the girls completes the HPV vaccination programme, 93 to 173 deaths could be prevented. This translates to a number of 578 to 1022 fully vaccinated girls to prevent 1 death.
About 421 cases of cervical cancer could be prevented by vaccinating girls against HPV.
Because the current number of vaccinated girls is significantly lower than 85% of the target group, the real numbers are lower than those estimated in the studies.[9]
QALY - Quality-Adjusted Life-Year
A QALY takes into account the quantity and quality of life generated by healthcare interventions, such as vaccinations. It's a measure for the quality of life for the remaining years. People living in perfect health generate QALYs of 1, whereas death would mean a QALY score of 0.
QALYs can be 'generated' by healthcare interventions, such as vaccinations. Sometimes, QALY points can be generated for a lower cost, as is the case for several vaccinations.
When making important decisions, the government takes into account the cost-utility ratios. Spending thousands of dollars on 1 person would generate only 1 QALY, whereas spending the same amount on giving people vaccinations against several diseases would generate more QALY points.
In the Netherlands, we generally deal with a cost-utility ratio(costs required to generate 1 year of perfect health, or 1 QALY) of €20k per QALY.[11]
For the HPV vaccine, the cost-utility ratio lies between €18.400 and €30.000, making it worthy investment.[9]
Even when enough ladies complete the HPV vaccination programme, screening should be continued, as the vaccine only takes care of 2 out of over 12 carcinogenic HPV viruses.[8]
[1] Parham, P., The Immune System, January 15th, 2009, Garland Science
[2] RIVM, The National Immunisation Programme in the Netherlands, 2010
[3] RIVM, Richtlijn Rijksvaccinatieprogramma 2012, december 2011
[4] RIVM, Vaccinatiegraad, 2012,
http://www.rivm.nl/Onderwerpen/Onderwerpen/R/Rijksvaccinatieprogramma/Inenten_beschermt/Vaccinatiegraad
[5] Madigan, M., Martinko, J., Stahl, D., Clark, D., Brock Biology of Microorganisms, 2011, Pearson
[6] RIVM, Kinkhoest, 2012
http://www.rivm.nl/Onderwerpen/Ziekten_Aandoeningen/K/Kinkhoest
[7] Roden, R., Wu, T.C., How will HPV vaccines affect cervical cancer?, September 27th, 2011, NCBI
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3181152/
[8] RIVM, HPV-inenting, date unknown
http://www.rivm.nl/Onderwerpen/Onderwerpen/R/Rijksvaccinatieprogramma/Prik_en_bescherm/HPV_inenting
[9] Westra, T.A., Daemen, T., Postma, M.J., Wilschut, J.C., Doelmatigheid van Humaan papillomavirus-vacinatie, October 29th, 2009,
Ned Tijdschr Geneeskd. 2009;153:A356
http://www.ntvg.nl/publicatie/doelmatigheid-van-ihumaan-papillomavirusi-vaccinatie/volledig
[10] Newby, K., HPV Vaccine: Pros and Cons, 2009, The Ohio State University
http://ohioline.osu.edu/hyg-fact/5000/pdf/5239.pdf
[11] Philips, C., Thompson, G., What is a QALY?, April 2009, Hayward Medical Communications
http://www.medicine.ox.ac.uk/bandolier/painres/download/whatis/QALY.pdf
This assignment on the Dutch National Immunisation Programme, Whooping cough and HPV was completed by a former student of VU University of Amsterdam / current student of AMC-UvA. I hereby give any other students my permission to use the info I've gained for their own assignments, although I cannot guarantee any high grades, nor do I recommend you to completely copy this from the internet.
This information is not meant to be placed on any other site, and I will hunt you down if I do find it somewhere.
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