From an article entitled, "It pays to get vaccinated"
Retrieved from The Star Online - http://www.thestar.com.my/news/nation/2016/07/08/it-pays-to-get-vaccinated-the-truth-about-vaccines-vaccination-is-still-the-best-way-to-prevent-dise/
PETALING JAYA: There has been a deluge of information over social media on the controversial issue of vaccination.
Prof Dr Jacqueline Ho (pic), an honorary consultant in neonatology (a sub-speciality of paediatrics covering medical care of newborns, mainly premature births) was asked about the many questions raised.
he Malaysian Cochrane Network (MCN) convener from Penang Medical College explained why vaccines play a crucial role in safeguarding health.
MCN is part of the 20-year-old Cochrane Collaboration network of more than 28,000 dedicated staff from over 100 countries who gather evidence on health intervention studies.
The following is an excerpt of The Star’s interview with Dr Ho.
There are claims that some infectious diseases were on a downward trend even before vaccinations were introduced. What is your view?
The improvement in living standards has been over a longer and more sustained period. It cannot be explained, the sudden disappearance of diphtheria over such a short period following the introduction of the vaccine. I don’t think better living conditions can control diphtheria. When the diphtheria vaccine was introduced, it disappeared in less than 10 years.
In the United States, there were nearly 20,000 diphtheria cases a year between 1940 and 1950 and it dropped from that to less than a 1,000 cases between 1950 and 1960.
There has been no decrease in influenza cases due to better living conditions. In fact, there might be more flu cases now as manifested by the occurrence of worldwide epidemics since we live in big cities, travel on mass transit systems and aeroplanes, sit in school with other children and work together in the same air-conditioned offices.
Outbreaks still take place in unimmunised pockets of the population and deaths occur.
If there are large unimmunised pockets of the population, then very occasionally a child who has been immunised but for some reason failed to develop antibodies might also get infected.
Without the vaccine, we could not have made the progress we have achieved today. Worldwide, millions of lives have been saved. Immunisation is one of the success stories of modern science. Vaccination is one of the key reasons why we have seen the huge drop in childhood mortality rates we see today.
Childhood diseases are a rite of passage for a child to build up strong immunityand hence, the view that they should not be vaccinated?
This is an old-fashioned cultural belief without scientific basis. Measles can kill and cause brain damage. The vaccine provides this immunity without the risks.
In fact the immune system can be damaged by a measles infection, and lead to the infected person being more susceptible to other infections such as tuberculosis.
There is a claim that those spreading diseases are the vaccinated ones, as they are the ones who are injected with the live virus and should be quarantined.
What evidence does the person have for this? It is relatively easy to check whether a case of measles is due to the wild strain or the vaccine strain.
It is true that a child may suffer a fever or mild rash after vaccination but the live attenuated vaccine virus does not spread to another person and, therefore, cannot cause outbreaks. This is why it is not necessary to quarantine vaccinated children.
In the case of diphtheria, the previously infected person is the main carrier. Those who get infected are those who are not immune. It gets passed from one non-immune person to another. The non-immunised who contract a mild form of the disease can carry the bacteria after the infection for up to six months.
It is wrong to think you can get the disease from immunised people, otherwise millions would have been infected!
Is it true that the vaccine-induced herd immunity is only in theory and has never been scientifically proven to work and does not guarantee immunity, while “efficacy” of the vaccine wanes and vaccinated individuals can still contract the disease (with or without symptoms) and spread it to others?
I disagree that it has never been proven scientifically to work. There is some truth in the statement that immunity wanes and individuals with low immunity could get infected but not to the level that it has caused outbreaks in older people.
The measles vaccine has been used since the 1960s in some countries (at that time the killed vaccine was used), meaning that there are many people alive today and are now over 50 years of age who might have died of measles when they were young. There is no evidence that their immunity has sufficiently waned up to this age to cause measles.
Vaccinating means putting in “attenuated” diphtheria bacteria into the body?
No, this is what is generally done with viruses. Diphtheria vaccine is a toxoid, a chemical that resembles the toxin produced by a toxic strain of diphtheria. When it is injected into a person, it tricks the body into producing antibodies against the toxin. The toxoid itself does not do anything. It is a benign chemical.
Diphtheria can be treated by antibiotics unless it is too late?
It can be treated with antibiotics but is not always successful because the toxin is what causes death. The toxin can be produced very early before the parent realises the child is sick. Antibiotics will get rid of the bacteria but the child may still continue to be sick or even die from the toxins. The main role of antibiotics is to prevent the spread to others.
Some parents overseas have claimed that the Hepatitis B vaccine triggered severe arthritis in their children.
There has been debate about this because one paper in the 1990s reported that 11 cases of arthritis (10 were rheumatoid arthritis) appeared to be associated with the Hep B vaccine.
This has been followed by other case reports. It was thoroughly reviewed by the WHO global vaccine safety group and other bodies, and they wondered whether there might be a small group of people susceptible to rheumatoid arthritis triggered by the vaccine.
However, they came to the conclusion that there is no convincing evidence for such an association and did not suggest any change in their recommendations.
The live attenuated vaccines are created by reducing the virulence of a pathogen while still keeping it viable, but viruses evolve and it is not known how the virus would evolve in the body. Your views please?
Scientists are concerned about this, too. There is a small risk of “re-virulence”. Surveillance systems such as the Centre of Disease Control are always on the lookout for this but have yet to see it.
The main concern with live attenuated vaccines is with children who are immune compromised. As I have previously stated, even normal children can get a mild modified form of the disease with immunisation with an attenuated virus.
In the Cochrane review on flu vaccine, children who received the vaccine and those in the placebo group had fever but about 2% more who received the vaccine developed a fever compared to those who did not receive the vaccine.
With the measles vaccine, a small group of children may actually get a mild measles-like rash. This means that the child definitely responded to the vaccine and would be immune.
The concerns also included how scientists remove the critical elements in the virus.
In fact those attenuated viruses that are produced by removal of the virulent part of the viral gene are far less likely to have an issue with the return of virulence.
There are often several virus serotypes out there and it is not known to what extent people could take a jab with several serotypes or a combo vaccination such as the MMR (mumps, measles and rubella).
MMR doesn’t have an issue with serotypes (because they are enveloped viruses) but influenza does. The influenza vaccine is redesigned every year to meet the current serotypes. This is why it has to be administered every year.
One mother said vaccination is necessary but fears that babies are taking too many vaccines at one go and the body may not be able to handle it.
This is not a new argument. We do know that one immunisation might interfere with another while some work even better when given in combination. This is always evaluated during laboratory experiments and trials long before a vaccine is marketed. It is also part of the reason why the spacing of vaccines is timed as it is.
