Archive for May, 2011

Influenza vaccines will be enough for half the population – so who should get them?

Saturday, May 28th, 2011 (last updated)

While the CDC is advising everyone to get a flu or influenza shot, vaccine makers say this is not necessarily true – some people may not need a repeat shot. Whoever is right, even with record production for this coming fall, only half the US population will be able to get vaccinated.

Vaccine makers say this season’s shot will be a duplicate of last year’s. This is because the same influenza strains are circulating. If this is the case, young, healthy individuals may still be immune from last season’s shot and may not need a booster.

It is inevitable that members of the public will become confused and frustrated with conflicting advice. Government health officials say that the protection offered by one season’s shot can diminish rapidly, especially for frail, elderly people, as well as those with weakened immune systems.

Earlier this month, five vaccine makers said they plan to produce from 166 to 173 million flu vaccine doses for the coming influenza season, surpassing the previous record by 6 million.

Americans are taking flu shots in ever growing numbers; over the last ten months over 40% of the population has been vaccinated, compared to 30% in previous years.

The CDC (Centers for Disease Control and Prevention) has been aggressively promoting flu shots as a public health priority. It says everyone should be vaccinated, except for children under 6 months of age, individuals with egg allergies, and some other conditions.

US authorities have become more aggressive in promoting flu shots than their European counterparts.

Health authorities tend to use the changing flu strains argument when encouraging people to get vaccinated. As the same strains as last year are expected to be circulating this coming fall, many experts say that not everyone necessarily needs two consecutive years of shots.

The CDC says that at the best of times, flu shots are only about 70% effective. Repeat shots should be given to as many people as possible to protect a whole population, they say.

Studies do not seem to agree on how quickly a flu shot’s protection starts to wane. According to the CDC, one’s immunity drops by at least 66% over a year. Other studies suggest that in children protection last for up to three years, and at least one year in adults.

The truth is nobody, not even the experts, really know how long protection lasts. If nobody is really sure, surely the best bet is to vaccinate as many people as possible.

Clinical trial of malaria vaccine in phase III

Thursday, May 26th, 2011 (last updated)

The vaccine, RTS,S, developed by GlaxoSmithKline (GSK) Biologicals and PATH Malaria Vaccine Initiative (MVI), is currently in phase III clinical trials and has previously reduced episodes of malaria in infants and young children by more than 50%. The Liverpool team, in collaboration with the University College of Medicine, Malawi, are working in Blantyre over the next three years to investigate how to maximise its effectiveness when delivered through the childhood immunisation programme.

Malaria is a life-threatening parasitic infection, resulting in more than 200 million reported cases each year and approximately 800,000 deaths. In Africa a child dies of malaria every 45 seconds and the disease accounts for 20% of all childhood deaths. Scientists will assess the possible benefits of providing the vaccine to newborn babies, similar to the routine programme currently used for other vaccines, such as BCG for tuberculosis, Hepatitis-B and oral polio vaccines.

The team will examine the performance of the vaccine as it is administered to infants at different stages between birth and nine months of age, alongside the standard set of immunisations used in national programmes for young children. Studies have so far suggested that the vaccine could be safely integrated with other vaccines in the World Health Organisation’s Expanded Programme for Immunisation (EPI) schedule.

Leading the study from Malawi, Dr Desiree Witte, from the University’s Institute of Infection and Global Health, said: “Young children are particularly susceptible to infection with malaria and it is important that vaccines are introduced into the immunisation programme as early as possible. There is no licensed vaccine available against malaria and currently the candidate vaccine developed by GSK and MVI, is the most clinically advanced malaria vaccine in the world. The evaluation of different immunisation schedules will help define the programme needed for the vaccine to be administered successfully.”

Professor Nigel Cunliffe, also from the University’s Institute of Infection and Global Health, added: “Over the past few years there have been encouraging results from studies of vaccines aimed at tackling some of the major diseases common to children living in Africa, including diarrhoea, pneumonia and malaria. It is hoped that in the near future vaccines against these diseases will become a standard part of the immunisation schedule across the region. It will therefore become increasingly important for us to understand how the vaccines will work when administered alongside each other.”

Professor Tom Heikens, Head of the University College of Medicine’s Department of Paediatrics and Child Health, Malawi, said: “As well as developing this important area of research, the work is allowing postgraduate students at the College to gain valuable insight into child health and the medical challenges Malawi faces. Collaborations such as this contribute greatly to identifying the next generation of researchers to take this important area of study forward.”

Vaccination: 20 objections & 20 responses

Wednesday, May 25th, 2011 (last updated)

The ECDC (European Centre for Disease Prevention and Control) translated a document that contains a list of objections frequently raised by people opposed to vaccination and responses from immunisation specialists. This document was originally prepared by the Robert Koch-Institute and the Paul-Ehrlich-Institut from Germany.

Were this assumption actually true, commercial vaccines would not exist. According to the current pharmaceutical law in Germany, a vaccine is licensed only if it has been demonstrated that it actually works. The manufacturer is required to provide proof of its effectiveness in experimental and clinical studies. The scientific evidence is examined on the level of the European Union (EU) under the direction of the European Medicines Agency (EMEA). In Germany, the responsibility lies with the Paul Ehrlich institute as the Federal Agency for Sera and Vaccines. That is the legal side of it. Of even higher importance is probably the test in practice. There is clear evidence that the routine introduction of certain vaccines has led to a significant drop in the corresponding diseases. A well-known example is the introduction of the oral polio vaccine in the early 1960s: while almost 4,700 children in the Federal Republic of Germany (FRG) came down with child paralysis (poliomyelitis) in 1961, this number had gone down to less than 50 as early as 1965. Following this success, there have not been any more clusters of poliomyelitis in Germany (see also no. 17). A similar impact had the immunisation against the bacterium Haemophilus influenza type b (Hib) that can cause severe meningitis in infants and toddlers. We know that in the former German Democratic Republic (GDR), where infections were registered very precisely, between 100 and 120 such meningitis cases occurred annually in the years before the reunification. When the Haemophilus vaccination was introduced in Germany in 1990, the annual case number in the former East German states fell rapidly to under 10.

Where there is no pathogen, there is now vaccination – this is a fundamental law in microbiology. Vaccines are produced on the basis of weakened (attenuated) or dead 2 (inactivated) germs, or on the basis of their molecular components. Sometimes, they are produced from other pathogens that are closely related to the disease-causing germs. The body’s immune system is thereby being prepared for the actual infection. Without specific knowledge about the pathogens themselves, however, the systematic development of vaccines would not have been possible. Robert Koch established the essential methodological foundations of bacteriological research. His achievements include the development of solid media for the cultivation of bacteria as well as the introduction of micro-photography that contributed significantly to the widespread use of bacteriology in medical research. As district physician in 1876, he discovered the anthrax spores, the dormant form of the anthrax bacterium, and thus understood the – at the time unexplained – chain of infection and the high robustness of the bacterium against environmental factors. Robert Koch was therefore the first to demonstrate a causal connection between a micro-organism and an infectious disease. Viruses on the other hand could not be made visible for a long time, because they are too small to be seen in the light microscope. This showed clearly the physical limits of light microscopy. Thanks to the development in the 20th century of electron microscopy, which allows a much higher resolution than light microscopy, detailed pictures of numerous viruses are available today. We now even know the genetic code of many pathogens. This knowledge is used for instance to genetically engineer yeast cells to produce the hepatitis B vaccine. This vaccine consists of just one specific surface molecule of the hepatitis B virus, the so-called HBs antigen. Influenza vaccines on the other hand are still produced in a much more traditional way: The influenza viruses are grown in chicken eggs, then killed, and processed to highly purified vaccines.

Whether a vaccination needs to be repeated or not differs from case to case. If, for example, a child has received as part of the basic immunisation schedule two injections with the combined vaccine against measles, mumps and rubella, one can assume that the protection will actually last for life. Things look differently with tetanus, diphtheria, polio, or whooping cough. With immunisations against these diseases one can rely on five to ten years of protection – then they should be renewed. Even shorter is the protection conferred by an influenza vaccination. As the influenza virus mutates enormously fast, vulnerable individuals need to renew their immunisation every year with a newly composed vaccine. That the effect of a vaccine is only temporary does of course not mean that it is useless. Thus the annual influenza immunisation can prevent a life-threatening course of disease in chronically ill patients or in the elderly. Also the immunisation against tetanus that is due every 10 years seems a minor inconvenience in the face of the potentially deadly infection. However, even people who have gone through a disease and recovered may not have developed durable immunity. One can contract tetanus, and also diphtheria or whooping cough, several times in life. There have even been some reports of people contracting measles twice.

Just as no drug is effective in all patients, no single vaccine confers 100 percent protection to the vaccinee,. However, immunisation significantly reduces the likelihood of an illness. Imagine the following scenario: a measles epidemic occurs in a primary school. Half of the children are immunised, the other half not. Statistically, one can expect about 97 or 98 percent of the unprotected pupils to get sick – but only two to three percent of the vaccinated pupils. The influenza vaccination, however, is less effective. Depending on one’s age and state of health, it protects 50 to 90 percent of vaccinees against the flu. The vaccine is usually least effective in old people. Likewise, if a necessary booster vaccination has been missed or immune protection is not yet fully established, the protection often remains incomplete. Thus, the traditional childhood vaccinations at first need to be repeated several times according to a regulated schedule before one can count on a reliable and durable protective effect. There are also immunisations that prevent only a particularly severe course of disease. This is the case with the Bacille Calmette-Guérin (BCG) vaccination against tuberculosis that was routinely applied to infants in most European countries until the late 1990s, but that has meanwhile been taken out of the regular immunisation schedule in most of these countries due to the comparatively low likelihood of contracting the disease. Although the vaccine did not protect the children from a tuberculosis infection as such, it did protect them from its worst complications, which involve the entire body and brain.

So far, there are no scientific studies that show any advantage of non-vaccinated over vaccinated children with regard to their mental or physical development. Nor would this be plausible. Immunisation is directed against around a dozen particularly notorious and dangerous pathogens – the immune system has to deal with hundreds of other pathogens every day. The vaccination itself also stimulates and trains the immune system. Accordingly, it would be highly surprising if vaccinated children in general had a weaker constitution or reduced immune defences. Evidence that would support such a theory does not exist. In addition, it has to be noted that even if one assumed that going through certain diseases was somewhat beneficial, there can be no doubt that infections can influence the development of children negatively and cause complications and even deaths. Exactly this can often be prevented by immunisation.

It is correct that many infections heal without consequences. Nevertheless, even so- called childhood illnesses can in certain cases take a dramatic course. Childhood illness does not mean that the illness is harmless, but that it occurs preferentially in children. The best example is measles: About one in 1,000 children who have measles, develop an inflammation of the brain, the so-called measles encephalitis. This often leads to permanent brain damage or even death. In about one in a million cases such an encephalitis can even occur after vaccination – this is 1,000 times less frequently than after the disease. Also the fever cramps that often occur in measles patients can to a large extent be avoided by the vaccination. While approximately one in 15 measles patients suffers from such cramps, they affect only one in 100 vaccinees. Similar issues apply to childhood diseases such as mumps or rubella. When Mumps occurs in young men, it can sometimes lead to inflammation of the testicles and impaired fertility. Rubella on the other hand, if contracted by a pregnant woman who is not immune against the disease, can cause severe malformations in the unborn child. These severe consequences can be prevented by immunisation in as good as all cases. Finally it has to be said that in the past, the possibility of vaccination did not exist for many diseases, just like there were no seatbelts in the cars, no motorcycle helmets, and no protective bicycle helmets. Today, all these possibilities for protection exist, and people are happy to use them.

Antibodies are indeed transferred during pregnancy from the mother to the unborn child via the bloodstream. With the breastmilk, the infant receives further immune factors. Particularly during the first months of life, this maternal protection provides crucial support to the child’s developing immune system – but it does not cover everything. Since these antibodies are rapidly degraded, the child is left completely without protection as soon as the mother stops breastfeeding. The mother can pass on antibodies against diseases that she has had herself or against which she has been vaccinated. Against certain infections such as whooping cough, however, the immune system does not produce transferable antibodies, not even during the illness – so the baby is not protected against those diseases in any case. Furthermore it is well known that this passive protection is not strongly developed in premature infants, who therefore profit from vaccinations even more. Passive immune protection and vaccinations are not opposing concepts anyway; in some cases they rather complement each other. Thus Swedish paediatricians have found out that children who are breastfed suffer less frequently from severe meningitis caused by the bacterium Haemophilus influenzae type b (Hib), and in addition produce more protective antibodies against this pathogen after receiving a Hib vaccination. Only through a completed vaccination regime, meningitis can almost always be avoided.

For measles, mumps and rubella this has been proven true. A vaccination against these diseases stimulates the mother’s immune system less strongly than a real infection with the wild virus, which is why the baby of a vaccinated mother has proportionally less maternal antibodies. For this reason, paediatricians today generally give the first vaccine against measles, mumps and rubella a little earlier than it was done 20 years ago. For some other diseases, however, there is no such connection. During an infection with whooping cough for example, the mother’s immune system does not produce any transferable antibodies, and consequently, the baby in that case does not benefit from the maternal immune protection. On the contrary, it is known that adults can become infected with whooping cough several times in life and then often transmit the germs unnoticed to their children. According to a study done in the United States in 2007, parents and close relatives are by far the most frequent source of infection, when a newborn child contracts whooping cough. The German standing committee on vaccination (STIKO) at the Robert Koch institute therefore recommends vaccinating possible contacts already before the child is born. For still other diseases such as tetanus or diphtheria, maternal immune protection can be found in babies of vaccinated mothers but not in babies of mothers that had the infection.

Certain infection affects infants considerably more than older children – this is a fundamental reason why babies are immunised against various diseases already at the age of two months. Classic examples are infections with the bacterium Haemophilus influenzae as well as whooping cough. About one in four children with whooping cough develop complications such as pneumonia or respiratory arrest, if they are younger than six months. Later, the rate of complications drops to about one in 20. Infants therefore profit in particular from an immunisation against whooping cough. Already the first dose of the vaccine at the age of two months can reduce by about two thirds the likelihood that the baby needs to be hospitalised because of whooping cough. The booster vaccinations during the first year make the protection against whooping cough complete. That infants in general tolerate vaccination less well than older children is not documented. It is true that in extremely premature babies that are born before the 32nd week of pregnancy, heart and lung activity needs to be monitored after certain vaccinations in order to detect possible complications rapidly. But on the other hand, premature infants are also more vulnerable to infections – the risk-benefit ratio is therefore positive even in those cases. However, by no means all vaccines are administered already at this early age. The immunisation against measles, mumps and rubella, as well as against special bacteria that cause meningitis – the so-called meningococci – is only done around the age of one year.

Whilst it is true that children nowadays are immunised against more illnesses than in the past, the number of foreign molecules, so-called antigens, that are introduced with those vaccines has decreased considerably. Thus the old whooping cough vaccine alone contained around 3,000 such foreign molecules. In contrast, all of today’s vaccines together contain only 150 antigens. The reason for this is that the modern vaccines are highly purified and for the most part contain only a single component of a pathogen. In fact, the child’s immune system needs to deal every day with a much larger number of foreign molecules than the ones it is exposed to by immunisation. Moreover, there are no indications that combination vaccines overload the immune system. However, it is known that certain vaccine components stimulate the immune system less well when given in combination rather than as an individual vaccine, which can make it necessary to have four injections instead of three. But in the end, the number of necessary injections can still be reduced significantly by using combination vaccines. Nowadays, up to six vaccines – against tetanus, diphtheria, whooping cough, Haemophilus influenzae, polio und hepatitis B – can be combined in a single vaccine shot. Frequent criticism regarding the sixfold vaccine is that hepatitis B is predominantly – although by no means exclusively – transmitted through sexual contact, and newborns are therefore unlikely to contract it. However, hepatitis B in newborns is almost always a very severe disease and becomes chronic in 90% of the cases. Practical considerations also play a role in choosing to immunise newborns against hepatitis B. It is known that the vaccination rate in adolescents is generally low, although a hepatitis B infection can lead to severe disease and, when it becomes chronic, even to liver cancer. The German standing committee on vaccination and the World Health Organization therefore recommend immunisation against hepatitis B already at a young age. According to current knowledge, this could achieve longterm, possibly even lifelong, protection in a large proportion of vaccinees.

Certain vaccines can indeed cause mild symptoms resembling the disease – but virtually never the full-blown disease. The best-known example is measles. Since the measles vaccine contains attenuated (weakened), but live, measles virus, it can cause a measles- like rash in about 5% of vaccinees, which occurs about one week after immunisation. However, inflammations of the middle ear or the lung, which can accompany the actual disease, are not caused by the vaccine. Also the dreaded inflammation of the brain (measles encephalitis) is extremely rare after immunisation. It occurs in about one in one million vaccinees, whereas it affects one in a thousand children who have the actual measles. Patients that have developed poliomyelitis due to the oral polio vaccine have become historical in most European countries. The live vaccine which has helped reduce poliomyelitis on a large scale, itself caused a small number of infections every year. However, since 1998, this oral polio vaccine has been replaced in most European countries by an injection that does not contain live virus and cannot cause the disease. Many vaccines consist of dead pathogens or, as for instance the influenza vaccine, only of molecular components of the pathogens; only very few contain attenuated, still living pathogens. Quite apart from the connections mentioned above, immunisations can sometimes be followed by fever, nausea or drowsiness, as well as swelling and redness at the site of injection. But these are general, and usually rapidly subsiding, reactions of the body. They have nothing to do with the infectious disease against which the immunisation is directed.

What is certain is that we nowadays have more vaccinations – and more allergies. But whether one is connected to the other is not documented. Swedish doctors, it is true, have shown a few years ago that children from anthroposophical families were less prone to develop eczemas. Indeed, these children were vaccinated less frequently. However, they also received fewer antibiotics and a different diet, and their parents smoked less. In another study, American allergy specialists observed that children of parents who oppose immunisations suffer less frequently form asthma or hay fever. But also in this study it remained unclear whether there really was a causal connection. Many other studies argue against such a connection. An analysis done by doctors from Rotterdam, for instance, who evaluated all scientific articles published on the topic between 1966 and 2003, showed that especially the methodologically more reliable pieces of research could not find an increased allergy risk following immunisation. An experience made in Germany points into the same direction: In the former GDR, where vaccination was compulsory by law and almost all children were vaccinated, there were hardly any allergies. They increased in East Germany only after the reunification, while at the same time the vaccination rate decreased.

The assumptions are many: Again and again it has been debated in the past years whether autism, diabetes or even multiple sclerosis can be caused by immunisations. To this day, proof of this does not exist; on the contrary, numerous studies argue against it. A group of British scientists, for instance, hypothesised at the end of the 1990s that the measles-mumps-rubella (MMR) vaccine could cause damage to the intestine and thus facilitate the entry of neurotoxic substances into the body. They further hypothesise that this would interfere with the mental development and favour autism. Meanwhile, however, several other studies have disproved this thesis – 10 of the original 13 authors withdrew the interpretation officially. Nevertheless, vaccines without question do have side effects. Thus a total of about 44 million vaccine doses were sold in Germany in 2005; about half of them were for the annual influenza jab. In the same period, doctors and pharmaceutical companies reported just under 1,400 supposed vaccine complications – corresponding to a rate of about three suspected cases per 100,000 doses sold. As shown in a detailed analysis of all suspected complications by the Paul Ehrlich institute in Germany, there was no indication of a possible causal connection with the immunisation in about a third of the reported cases. Furthermore, a large proportion of the reported health problems – for instance high fever – were temporary. In only five vaccinees was a permanent health impairment reported, which may have been caused by the vaccination. In the case of one adult who died after an immunisation, a causal relation with the vaccination could at least not be completely excluded. Actually, a major difficulty in the risk assessments lies in the fact that vaccinations are so common that many health problems can occur after an immunisation by pure chance. A genuine connection does not necessarily exist at all. A few years ago, for example, it was discussed whether vaccinations would favour cot death, since a number of children had just died after an immunisation. Meanwhile, studies rather point towards the opposite. Thus doctors at the university of Magdeburg in Germany have recently performed a comprehensive analysis of around 300 cases of cot death and discovered that the deceased babies had in fact been vaccinated less frequently and later than usual.

Certain vaccines contain formaldehyde, aluminium, phenol or mercury – but only in minute concentrations (below the toxicological threshold). These substances serve the purpose of, for example, killing the vaccine viruses (formaldehyde), enhancing the immune response (aluminium hydroxide) or act as a preservative (phenol). Some years ago two American doctors had proposed the thesis that the rise in autism cases noticed in the United States was linked to the mercury-containing preservative thiomersal that is part of certain vaccines. The World Health Organization WHO, the United States Institute of Medicine, as well as the European Medicines Agency EMEA, however, have meanwhile independently from each other reached the conclusion that the available studies argue against such a link. Nevertheless, some pharmaceutical companies have reacted to the fierce debate: Mercury-free vaccines are now available for all generally recommended immunisations.

It is correct that, the serum of calves, for instance, is necessary as a component of the cell culture medium in which certain vaccine viruses are grown. However, only certified products from BSE-free countries such as New Zealand are allowed for this purpose. Equally strict are the controls for certain protein components, the so-called human albumin that is obtained from the blood plasma of blood donations. These proteins sometimes serve the purpose of stabilising and preserving live vaccines. In order to exclude a transmission of human immunodeficiency virus (HIV) or hepatitis viruses, plasma products are systematically tested for those pathogens. Further along the production cycle there are procedures to kill possibly undetected viruses.

Few doctors are altogether against immunisation. However, there are indeed some who have a critical attitude towards individual vaccinations – which does not mean per se that there are sound scientific reasons for it. Personal experience and religious or philosophical beliefs also play an important role.

However, an approach based on alternative medicine does by no means need to be in conflict with the idea of immunisation. A few years ago, researchers from Freiburg, Germany, condcuted a survey among 200 doctors with a homeopathic orientation. The found out that those doctors administered the “classic” vaccinations against tetanus, diphtheria and polio almost as frequently as their colleagues in conventional medicine. With other immunisations, though, the homeopaths were more reserved.

The German Central Association of homeopathic doctors (DZVhA) emphasised in a statement from 2002 that a discussion about the benefits and disadvantages of immunisations was perfectly legitimate and the decision for or against needed to be made on an individual basis. At the same time, however, the DZVhA confirmed the importance of the German standing committee on vaccination (STIKO) at the Robert Koch institute whose recommendations were “carefully considered and took into account the current state of knowledge with the intention of preventing, categorically, many infectious diseases.”

Some infections such as polio or diphtheria have become extremely rare in Europe. But this is in itself the result of vaccination programmes. Falling vaccination rates would always bring the danger of new epidemics. This is exemplified by the poliomyelitis outbreaks in the years 1978 and 1992 in Dutch municipalities in which immunisations were refused on religious grounds. 110 people contracted polio during the first epidemic, 71 people during the second. Even more dramatic were the diphtheria waves in Russia and the other post-Soviet states, where more than 150,000 people fell ill and more than 6,000 died in the 1990s as a result of falling vaccination rates. In the course of such epidemics, international travel can export infections to Germany [neighbouring countries]. Polio, for instance, still occurs in India and Egypt, popular holiday destinations. But even in Germany, there are recurring epidemics of, for example, measles, such as the one in North Rhine-Westphalia that affected around 1,700 children in 2006. Overall, the measles rate in Germany is still high compared to other European countries. In addition, other pathogens such as the hepatitis B virus or the bacteria causing severe systemic childhood inflammations – the so-called pneumococci – circulate in the population practically all the time. Infants, who contract a pneumococcal inflammation, often need to be hospitalised. However, an extensive study in the United States has shown that the routine pneumococcal vaccination, which has now been recommended for some years also for babies in Germany, can reduce the number of hospitalisations by almost half. Since the beginning of 2007, a completely different kind of immunisation has entered the scene: an immunisation against certain types of so-called papillomaviruses for girls between the age of 12 and 17. The viruses that are often transmitted during sexual intercourse can later in life cause cervical cancer. The majority of those cases could be prevented by the new vaccine.

Today’s treatment options are no doubt better than in the past – but by no means arbitrary. Drugs against viruses are rare; antibiotics do not work against viruses. And even some bacterial diseases are very hard to treat. Thus, among others, tetanus infections, meningitides and whooping cough can be fatal even under modern treatment conditions. In fact, vaccination and therapy are not alternative options, but part of the same chain of protection. Although vaccination does not always prevent the infection, it does prevent its most severe progressions.

Undoubtedly prosperity and hygiene contribute significantly to the prevention of infectious diseases. The provision of clean drinking water and the establishment of good hand hygiene, for example, are essential for the prevention of hepatitis A, typhus and cholera. Nevertheless, an overall connection between hygienic conditions and infectious diseases does not exist. Thus some pathogens, such as the measles, hepatitis B and polioviruses live exclusively inside the human body and are spread from human to human, for example by sexual contact or coughing It is true that for instance measles infections take a particularly severe course in malnourished children. The actual risk of infection, however, is closely linked to how many children are vaccinated against measles. If the immunisation rate is approximately 95%, measles can be completely eliminated. Thus, as a result of consistent immunisation programmes, the entire American subcontinent can be regarded as virtually measles-free. In sub-Saharan Africa, India and south-east Asia, on the other hand, measles is still one of the most frequent causes of death. In 1999, far more than 800,000 children died of measles in those areas. Large- scale vaccination campaigns, in which more than 360 million children were immunised in Africa and Asia, reduced the number of deaths to around 350,000 in 2005. In the long term, the World Health Organization strives to eliminate measles world-wide. This requires further efforts even in Europe. For example in Germany, the vaccination rates have risen in the past years, and more than 90% of children in their first year of school have received the first, and around 84% also the second measles vaccination, according to a German investigation in 2006. However, at least 95% for both shots are necessary for elimination.

Also the businesses in other industries earn money with their products; this is the goal of all companies. However, medicines for chronic patients, which need to be taken the whole life, would probably be more profitable than vaccines, which usually need to be administered only a few times. Sales for the pharmaceutical industry can often lead to considerable public health savings. Thus for every Deutschmark spent in the old West German states on the oral polio vaccination, 90 were saved in therapy and rehabilitation costs. Today’s vaccination against whooping cough reduces the treatment costs by more than 200 million Euros per year. Also the immunisation against hepatitis B – which meanwhile is generally recommended – is estimated to achieve cost savings to the health system in the long run, after initial extra costs for the health insurance companies.

  • Alm JS, Swartz J, Lilja G et al (1999). Atopy in children of families with an anthroposophic lifestyle. Lancet 353: 1485-8
  • Dittmann S (2002) Risiko des Impfens und das noch größere Risiko, nicht geimpft zu sein. Bundesgesundheitsblatt – Gesundheitsforschung – Gesundheitsschutz 45: 316-22
  • Enriquez R, Addington W, Davis F et al (2005) The relationship between vaccine refusal and self- report of atopic disease in children. Journal of Allergy and Clinical Immunology 115: 737-44
  • Geier MR, Geier DA (2003) Neurodevelopmental disorders after thimerosal-containing vaccines: a brief communication. Experimental Biology and Medicine 228: 660-4
  • Grijalva CG, Nuorti JP, Arbogast PG et al (2007) Decline in pneumonia admissions after routine childhood immunisation with pneumococcal conjugate vaccine in the USA: a time-series analysis. Lancet 369: 1179-86
  • Hartmann K, Keller-Stanislawski B (2002) Rekombinante Hepatitis-B-Impfstoffe und Verdachtsfälle unerwünschter Reaktionen. Bundesgesundheitsblatt – Gesundheitsforschung – Gesundheitsschutz 45: 355-63
  • Heininger U (2004) Risiken von Infektionskrankheiten und der Nutzen von Impfungen. Bundesgesundheitsblatt – Gesundheitsforschung – Gesundheitsschutz 47: 1129-35
  • Jefferson T, Price D, Demicheli V (2003) Unintended events following immunization with MMR: a systematic review. Vaccine 21: 3954-60
  • Jilg W (2000) Schutzimpfungen. Kompendium zum aktiven und passiven Impfschutz, Ecomed Verlag Landsberg/Lech, 2. überarbeitete Auflage
  • Juretzko P, von Kries R, Hermann M et al (2002) Effectiveness of acellular pertussis vaccine assessed by hospital-based active surveillance in Germany. Clinical Infectious Diseases 35: 162-7
  • Koppen S, de Groot R, Neijens HJ et al (2004) No epidemiological evidence for infant vaccinations to cause allergic disease. Vaccine 22: 22(25-26):3375-853375-85
  • Lehrke P, Nuebling M, Hofmann F, Stoessel U (2001) Attitudes of homoeopathic physicians towards vaccination. Vaccine 19: 4859-64
  • Meyer C, Reiter S, Siedler A et al (2002) Über die Bedeutung von Schutzimpfungen. Bundesgesundheitsblatt – Gesundheitsforschung – Gesundheitsschutz 45: 323-31
  • Meyer C, Rasch G, Keller-Stanislawski B, Schnitzler N (2002) Anerkannte Impfschäden in der Bundesrepublik Deutschland 1990-1999. Bundesgesundheitsblatt – Gesundheitsforschung – Gesundheitsschutz 45: 364-70
  • Meyer C, Reiter S (2004) Impfgegner und Impfskeptiker. Bundesgesundheitsblatt – Gesundheitsforschung – Gesundheitsschutz 47: 1182-8
  • Murch SH, Anthony A, Casson DH (2004) Retractionof an interpretation. Lancet 363: 750
  • Ohne genannte Autoren (2000) Are booster immunisations needed for lifelong hepatitis B immunity? European Consensus Group on Hepatitis B Immunity. Lancet 355: 561-5
  • Pfister RE, Aeschbach V, Niksic-Stuber V (2004) Safety of DTaP-based combined immunization in very-low-birth-weight premature infants: frequent but mostly benign cardiorespiratory events. Journal of Pediatrics 145: 58-66
  • Quast U, Ley S, Arndt U (2005), Schwierige Impffragen – kompetent beantwortet, Kilian Verlag Marburg, 1. Auflage
  • Reiter S, Rasch G (2004) Schutzimpfungen. Gesundheitsberichterstattung des Bundes Robert Koch-Institut. Epidemiologisches Bulletin, 20. Januar 2006/ Nr. 3
  • Schwanig M (2002) Die Zulassung von Impfstoffen. Bundesgesundheitsblatt – Gesundheitsforschung – Gesundheitsschutz 45: 338-43
  • Siegrist CA, Aebi C, Desgrandchamps U et al (2005) Impfratgeber: Evidenz anstelle von Behauptungen. Schweizerische Ärztezeitung 86: 539-52
  • Silfverdal SA, Bodin L, Hugosson S et al (1997) Protective effect of breastfeeding on invasive Haemophilus influenzae infection: a case-control study in Swedish preschool children. International Journal of Epidemiology 26: 443-50
  • Silfverdal SA, Ekholm L, Bodin L (2007) Breastfeeding enhances the antibody response to Hib and Pneumococcal serotype 6B and 14 after vaccination with conjugate vaccines. Vaccine 25: 1497-502
  • Uchiyama T, Kurosawa M, Inaba Y (2007) MMR-vaccine and regression in autism spectrum disorders: negative results presented from Japan. Journal of Autism and Developmental Disorders 37: 210-7
  • Vennemann MM, Butterfass-Bahloul T, Jorch G et al (2007) Sudden infant death syndrome: no increased risk after immunisation. Vaccine 25: 336-40
  • Wakefield AJ, Murch SH, Anthony A et al (1998) Ileal-lymphoid-nodular hyperplasia, non- specific colitis, and pervasive developmental disorder in children. Lancet 351: 637-41
  • Weißer K, Bauer K, Volkers P, Keller-Stanislawski B (2004) Thiomersal und Impfungen. Bundesgesundheitsblatt – Gesundheitsforschung – Gesundheitsschutz 47: 1165-74
  • Weißer K, Meyer C, Petzold D et al (2007) Verdachtsfälle von Impfkomplikationen nach dem Infektionsschutzgesetz und Verdachtsfälle von Nebenwirkungen (von Impfstoffen) nach dem Arzneimittelgesetz vom 1.1.2004 bis zum 31.12.2005 (zugänglich unter www.pei.de)
  • Wendelboe A, Njamkepo E, Bourillon A et al (2007) Transmission of Bordetella pertussis to young infants. The Pediatric Infectious Disease Journal 26: 293-9
  • Wolfson LJ, Strebel PM, Gacic-Dobo M et al (2007) Has the 2005 measles mortality reduction goal been achieved? A natural history modelling study. Lancet 369: 191-200
  • Zepp F, Knuf M, Heininger U et al (2004) Safety, reactogenicity and immunogenicity of a combined hexavalent tetanus, diphtheria, acellular pertussis, hepatitis B, inactivated poliovirus vaccine and Haemophilus influenzae type b conjugate vaccine, for primary immunization of infants. Vaccine 22: 2226-33

Acknowledgement

This translation was done with the kind permission of the Robert-Koch institute and the Paul Ehrlich institute.

How vaccines work

Friday, May 20th, 2011 (last updated)

Vaccination is a proud badge of honor you can choose to give to your child. Simple as that. And when they’re protected, they’re good. They’re good to go out into the world and just be kids. Play with friends. Have adventures. Experience life the way only kids

Download this movie

Measles cases mounting in Europe

Wednesday, May 18th, 2011 (last updated)

According to a World Health Organization brief, continued outbreaks of the measles across Europe have caused the number of confirmed cases to rise to 7,028 in 38 countries as of May 6.

There may be a higher actual case of measles as a result of variations in reporting, which includes France’s reported 7,500 cases in the first three months of 2011, contrasted to the country’s total of 5,090 for all of 2010. Large and extended outbreaks are expected to continue in geographic areas where the coverage of two doses of measles-containing vaccine is below 95 percent.

Twenty-nine percent of the confirmed cases were in people who had received no doses of measles containing vaccines and 67 percent of the cases had been in people with no records or who did not know their vaccination status. Ten member states of the European Union reported measles outbreaks.

Spain has reported two measles outbreaks that began in October. The former Yugoslav Republic of Macedonia has reported 636 cases of measles from September through the first week of April, with over 400 diagnosed in 2011. Turkey, Serbia, Switzerland, Belgium, Finland, Denmark, Germany, Norway, Romania, the Russian Federation, Sweden and the United Kingdom have also reported outbreaks and an increase in the number of cases.

In nearly all the outbreaks, the D4 genotype of the measles virus was confirmed, except in Grenada, Spain, Turkey.

Two doses of mumps vaccine superior to one

Tuesday, May 17th, 2011 (last updated)

The analysis of a recent Ontario, Canada, mumps outbreak has indicated that two doses of mumps vaccine are more effective than one, showing renewed importance that people be up to date on their mumps vaccinations.

Researchers from the Ontario Agency for Health Protection and Promotion, the Ontario Ministry of Health and Long-term Care, the University of Toronto and the North Bay Regional Health Unit in Ontario compared the effectiveness of one and two doses of the measles, mumps and rubella vaccine between September 2009 and June 2010. Similar outbreaks occurred in New York and New Jersey in the United States and Israel at the same time.

Of 134 people in Ontario with confirmed mumps, 72 percent were male, 59 percent were between 15 and 24 years of age, and of the 114 people who had available vaccination history, the majority – 72 percent – had received no vaccine or only one dose.

Those born between 1980 and 1994 were more likely than expected to become infected, especially those aged 15 to 24. “The clustering of cases, particularly among people born between 1985 and 1991, reflects the susceptible cohort,” Dr. Shelley Deeks of the Ontario Agency for Health Protection and Promotion, wrote. “In addition, the active social lifestyle of this age group may have the transmission of the disease. The predominance of male cases was likely due to the settings in which they were exposed to the virus. These settings included athletic events, such as hockey tournaments, where there is frequent close contact between people.”

A review of 50 mumps outbreaks showed that the effectiveness of one dose of the MMR vaccine ranged from 73 percent to 91 percent, compared with the effectiveness of two doses, which ranged from 91 percent to 95 percent. While mumps outbreaks in countries with two dose vaccination policies are typically unusual, they have become more frequent since 2006.

“Outbreaks of mumps in Canada and abroad serve as a reminder that we cannot become complacent about vaccination programs or maximizing vaccine coverage,” the authors wrote, according to the Canadian Medical Association Journal. “Closely monitoring waning immunity will help to ensure that we have the necessary data for making policy decisions, such as whether a third dose of MMR vaccine is necessary or whether a different vaccine should be considered, and for evaluating the cost-effectiveness of the program.”

Study evaluates parents’ reluctance to vaccinate asthmatic kids

Sunday, May 15th, 2011 (last updated)

Concern over vaccine safety is one of the primary factors preventing parents from having their asthmatic children vaccinated for influenza, or flu, according to Michigan researchers. Parents who do not vaccinate their children are also less likely to view flu as a “trigger” for their child’s asthma, the researchers noted.

The study was presented at the ATS 2011 International Conference in Denver.

“When school starts in the fall, and during the winter season, many parents start dreading the cold and flu season,” said lead author Toby Lewis, MD, MPH, assistant professor of pediatric pulmonology at C.S. Mott Children’s Hospital in Ann Arbor, Mich.

“This is particularly true for parents of children with asthma, who recognize that ‘a little cold’ can quickly trigger an asthma attack. Fortunately, there is something that can be done to reduce the chances of getting sick from influenza, one of the common winter viruses, and that is getting a vaccination to help prevent this infection. ”

Influenza vaccination is recommended for all children, but especially for children with asthma to help prevent asthma exacerbations or ‘flares,'” Dr. Lewis added. “Despite this recommendation, vaccination rates remain low. The reasons for under-immunization are poorly understood.”

To determine parental attitudes toward the flu vaccine, and learn the reasons why some parents do not have their asthmatic children vaccinated, the researchers conducted a national survey from August 13 — Sept 7, 2010 of 1,621 parents; 237 parents indicated at least one child had asthma and were included in the final compilation of data.

“The parents included in the study were ethnically diverse and were from a broad spectrum of economic backgrounds,” Dr. Lewis noted.

Of those surveyed, 70 percent reported that they vaccinated their child against seasonal or H1N1 influenza during the prior winter season (2009-2010), and 65 percent stated that they planned to have their child vaccinated against influenza in the upcoming season (2010-2011), indicating consistency in vaccination behavior. The study also found that parents who did not vaccinate their asthmatic children against influenza were less likely than those that did vaccinate indicate that getting a viral infection was a “very important” trigger of their child’s asthma (53 percent vs. 72 percent), and were more likely to be concerned about vaccine side effects (60 percent vs. 26 percent) and getting sick from the vaccine itself (41 percent vs. 13 percent).

Vaccines and autism debate: science communication by Penn & Teller

Saturday, May 14th, 2011 (last updated)

Study finds that shingles, pneumococcal vaccines can be given together

Friday, May 13th, 2011 (last updated)

A study conducted by Kaiser Permanente found that administering both the herpes zoster and the pneumococcal vaccines to patients at the same time does not appear to compromise the protective effect of the zoster vaccine.

The new information may be important to patients who find it less costly and more convenient to receive both vaccines from their healthcare providers at the same time. A revision to the zoster vaccine package insert, approved in 2009, said that the vaccines should not be given together because of reduced immune response in the zoster vaccine.

“Our study found no evidence that receiving the zoster vaccine and pneumococcal vaccine on the same day would compromise the immune response necessary to protect against herpes zoster, also known as shingles,” Hung Fu Tseng, lead author and a research scientist with the Kaiser Permanente department of research and evaluation in Pasadena, California, said.

In comparing two groups, one receiving both vaccines at the same time and one that received them non-concurrently, the study found no statistically significant difference in incidence of shingles between the two groups.

“Ideally, when a new vaccine is introduced to the public, one should consider giving it at the same time as other vaccines to increase coverage levels and minimize administration costs, if there are no immune response issues or safety concerns,” Tseng said.

“This new study provides even stronger data because it relies on the measurement of the occurrence of disease rather than intermediate markers of immunity,” Tseng said.

New vaccine shows promise in stopping HIV

Friday, May 13th, 2011 (last updated)

Researchers in the United States have found that a new vaccine can protect macaques against the monkey equivalent of HIV known as SIV, offering protection to 13 of 24 rhesus macaques treated in the experiment.

The vaccine was still effective 12 months later in 12 of the 13 monkeys.  The researchers said the work, published in Nature, might “significantly contribute” to the development of an effective HIV/AIDS vaccine.

The vaccine – which used the genetically modified rhesus cytomegalovirus (CMV) – works by stimulating the production of a certain type of blood cell called “effective memory T-cells,” which may remain vigilant in the body long after an infection has abated.

While researchers in the field, like Professor Sir Andrew McMichael of Oxford University, welcomed the study, they said safety issues would need to be addressed before similar approaches could be tested in humans.

 “I’m excited by the science because it really does demonstrate that it may be possible to eradicate the HIV virus by a strong immune response,” McMichael said.

“But at the same time I’m scratching my head how to take this approach into humans. CMV is not totally benign, it does cause a number of diseases. If you’re giving people something you’re not going to be able to get rid of should it cause problems, then that’s quite a difficult risk to manage.”

Professor Louis J. Picker of the Vaccine and Gene Therapy Institute in Oregon, the lead author of the study, said that the issues of safety would be addressed in forthcoming work. He pointed out that early forms of the smallpox vaccine also carried risks to humans.

“On one level, 99 percent of people in sub-Saharan Africa are CMV-positive and half the people in the developed world are, so we know at lot about it and it’s mostly non-pathogenic, except in vulnerable populations like pregnant women,” Picker said. “We’re fully aware to make it available to humans, then the next step is to make a virus which retains or has an enhanced ability to make effector memory cells, but no longer has the capacity to infect vulnerable parts of the population.”