To make vaccines safer than the disease, the bacteria or virus is killed or weakened (attenuated). This apparent paradox is explained by two factors. In fact it is true that in an outbreak those who have been vaccinated often outnumber those who have not - even with vaccines such as measles, which we know to be about 98% effective when used as recommended. This is another argument frequently found in anti-vaccine literature, the implication being that this proves that vaccines are not effective. It seems clear from these experiences that not only would diseases not be disappearing without vaccines, but if we were to stop vaccinating, they would come back. citizens who had worked in the former Soviet Union. There were at least 20 imported cases in Europe and two cases in U.S. There were also major epidemics of diphtheria that occurred in the former Soviet Union in the 1990s, where low primary immunization rates for children and the lack of booster vaccinations for adults resulted in an increase from 839 cases in 1989 to nearly 50 000 cases and 1700 deaths in 1994. In Sweden, the annual incidence rate of pertussis per 100 000 children of 0–6 years of age increased from 700 cases in 1981 to 3200 in 1985. In Japan at around the same time, a drop in vaccination rates from 70% to 20–40% led to a jump in pertussis from 393 cases and no deaths in 1974 to 13 000 cases and 41 deaths in 1979. In the United Kingdom of Great Britain and Northern Ireland, a drop in pertussis vaccination in 1974 was followed by an epidemic of more than 100 000 cases of pertussis and 36 deaths by 1978. Three countries – the United Kingdom of Great Britain and Northern Ireland, Sweden and Japan – cut back the use of pertussis (whooping cough) vaccine because of fear about the vaccine.
We can look at the experiences of several developed countries after they allowed their immunization levels to drop. However, looking at the actual incidence of disease over the years can leave little doubt of the significant direct impact vaccines have had, even in modern times.įor example, since sanitation is not better now than it was in 1990, it is hard to attribute the virtual disappearance of diseases such as Haemophilus influenzae type b (Hib) in children in recent years in countries with routine Hib vaccination (from an estimated 20 000 cases a year to 1419 cases in 1993, and dropping, in the United States of America) to anything other than the vaccine. Better nutrition, not to mention the development of antibiotics and other treatments, have increased survival rates among the sick less crowded living conditions have reduced disease transmission and lower birth rates have decreased the number of susceptible household contacts. Improved socioeconomic conditions have undoubtedly had an indirect impact on disease. “If there are going to be travel restrictions and people can’t go anywhere unless they have got this vaccine passport, I think people will change their mind quite quickly about whether they want this vaccine or not.Ideas like this are very common in anti-vaccine literature, the intent apparently being to suggest that vaccines are not needed. Prof Beate Kampmann, director of the vaccine centre at the London School of Hygiene & Tropical Medicine agreed that as the number of those who have been vaccinated grows, many of those wavering may decide to have the jab.īut, she added, other factors may also play a role. “How younger people will fare is a bit unknown but they will be far down the list and millions will have had the vaccine already, so the hope is that the worries about the newness and speed of development will decrease.”īut Vanderslott added that more effort is needed to underscore the importance of vaccination in younger people, and offer clear and tailored messages to groups with particular conditions or situations. “The acceptance in older ages has been higher in surveys and vaccination seems to have been going quite smoothly,” said Vanderslott.
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