What is the state of human health? Several studies published recently shed light on our knowledge on this subject. The news is rather good and deserves to be known, despite many threats. Since 1950, global life expectancy has increased by almost twenty-three years, the equivalent of a generation! This progress concerns both rich and poor countries, although there remains a significant gap between these extremes. The spread of HIV and conflicts have not halted this progress.
Importantly, it is accompanied at least in France by an increase in healthy life expectancy, even if this increase automatically leads to an increase in the number of patients with chronic diseases, factors that combine to increase health spending. The Covid pandemic has weighed heavily since it caused a loss of at least 1.6 years of life expectancy worldwide, and this in a very heterogeneous way depending on the wealth of the countries and the quality of the public health policy measures taken. In France, the loss, of the order of six months, has since been compensated, thanks to the containment measures and then the vaccination campaign which limited the impact of the pandemic.
154 million lives saved
How can we explain this improvement in life expectancy? We can consider four essential factors: the improvement of sanitation facilities, access to drinking water, the improvement of the performance of health systems and progress in medicine including vaccination. The weight of the latter was measured in a very interesting work carried out by the World Health Organization (WHO) recently published in the Lancet. Over the past fifty years, WHO estimates that 154 million lives have been saved by vaccination against 14 infectious diseases.
It is infant vaccination programmes that have brought the greatest benefit, preventing many deaths from measles but also whooping cough, tetanus and bacterial meningitis, particularly in the poorest countries. It is estimated that 40% of the reduction in infant mortality during this period was the result of vaccination! There is no better justification for continuing and expanding infant vaccination programmes here and elsewhere.
Misinformation spread on the Internet
However, vaccination programs have not fully achieved their objective. In France, vaccination against papillomaviruses and the cancers they cause only concerns barely half of young girls and a handful of boys. Vaccination of the elderly, whose immune systems are less effective, against seasonal flu, pneumococci, shingles and respiratory syncytial virus is now often forgotten both by those concerned and by their doctors. Beyond a lack of vigilance, vaccine hesitancy fueled by social networks limits the scope of vaccination programs.
Thus, a recent survey shows that in France, 20% of the population agrees with the idea that mRNA vaccines used to prevent Covid disease modify the DNA of vaccinated subjects, a statement that is nevertheless false. Another study shows that more than fake news, it is misleading information, that is to say factually accurate but interpreted in a biased way, for example by confusing the concomitance of events (a vaccination campaign and an adverse event) with a cause-and-effect relationship, which is the most harmful.
Health professionals have a vital role to play in tirelessly explaining in an honest and intelligible manner why the benefit-risk analysis of vaccines is overwhelmingly positive! A possible relaxation of vaccination campaigns contributes to threats to our health in the same way as the spread of obesity, drug use including opiates, antibiotic resistance or the effects of pollution and global warming. Risks which, for the most part, primarily affect poorer populations.
Alain Fischer is president of the Academy of Sciences and co-founder of the Institute of Genetic Diseases
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