On May 8, 1980, the World Health Organization (WHO), at its large annual meeting, which was attended by representatives of all member countries, unanimously confirmed that smallpox had been eradicated from the entire planet. This is a historic moment, the culmination of a unique WHO program of which vaccination was the main weapon and in which thousands of health workers and other citizens around the world actively participated: the best combination of science and policy. The task was titanic, because eradication is not just zeroing the incidence in some regions or countries, but the disappearance of the disease throughout the world and the complete elimination of the responsible microorganism. Smallpox is the first and only human disease to date to have been eradicated.

Sending vaccines to the last village

As with most prevention issues, the last mile was the hardest. In the case of smallpox, this was the decade 1967-1977. Although the WHO clearly set itself the goal of eradicating smallpox from 1958 to 1959, progress in the first subsequent decade depended more on individual country initiatives without much coordination or funding from WHO. However, in 1967, when smallpox was still endemic in the 30 poorest countries in Africa, Asia and Latin America, the WHO launched its historic Intensive Eradication Program, as it was called, which gave priority to countries with the greatest needs and to combat global disparities in access to vaccination. Vaccines and materials for their administration, such as special bifurcated needles, gradually reached the last village at the expense of the program, while the training of smallpox managers and vaccinators reached the most remote corners of the world.

The core of the eradication program was the rapid detection of any cases of smallpox through systematic epidemiological surveillance, their strict isolation for the period of transmissibility, tracing their contacts through structured tracing, and vaccination of a wide range of people in the area. The approach was painstaking and required local ingenuity and diligence from literally thousands of invisible eradication participants. But it was effective: in 1977, the last person in history to contract smallpox through natural transmission, Ali Maui Maalin, a hospital worker in Merca, Somalia, was diagnosed. It took several more years for global eradication to be confirmed by systematic epidemiological surveillance.

The dreaded disease mainly affected young children

Smallpox was a terrible disease. It presented with a characteristic rash that was often thick, extensive, and especially intense on the face, becoming purulent and then crusted, and could leave facial deformity or blindness. In the most severe cases, diffuse bleeding occurred from lesions of the skin and mucous membranes. About 20-30% of those who get sick eventually die. There was no specific treatment – antibiotics did not work, since the culprit was a virus.

Smallpox left a mark in the history of mankind and had a serious impact on the demographic development of the population. In areas where it was endemic, it manifested itself mainly in the form of periodic epidemics, which mainly affected young children, resulting in high mortality in these ages. Older children and adults have typically been infected during previous waves of epidemics and have developed immunity that usually lasts a lifetime.

In areas where the smallpox virus did not circulate, for example, in places remote and isolated from endemic areas, smallpox could sometimes be introduced by sick travelers, traders or soldiers. In this case, the consequences were dramatic, since the entire population, including those of working age, was deprived of immunity. Historians agree that the decline of the Inca and Aztec empires after the first twenty years of the 16th century was caused less by the war machine of the Spanish conquistadors than by smallpox (and measles), to which the indigenous peoples had no prior immunity. unlike the conquerors.

“Blessing” in China a thousand years ago

The discovery of smallpox vaccination, and with it the wider discovery of the practice of vaccination, is one of the greatest achievements of human civilization. If we did not have this way of actively inducing immunity without the risk of disease, our self-evident perception of the world today would be very different. For example, global communications and exchanges would be far less developed if they were accompanied by the risk of fatal diseases, while our understanding of childhood, development, and the psychological needs of children would be dominated by the threat of death if one in five children lost their lives before they grew up. .

The first form of smallpox vaccination, the “blessing”, has its roots in folk medicine. There are reports of its practice in China from the 11th century AD, and it was popular throughout most of Asia well before the 18th century, when it became known in Europe and became part of the accepted medical practice. This was facilitated by the Greek physicians of Constantinople, Iakovos Pilarinos and Emmanuel Timonis, who covered the practice and in 1714 published their observations in the London journal Philosophical Transactions. The method consisted in taking fluid from the patient’s blisters, which was grafted onto the skin of healthy people after scratching. But the “blessing,” although beneficial compared to smallpox itself, had serious drawbacks. The reaction caused by it, although usually mild, was sometimes severe and resulted in death in 1-3%, while the virus could spread among those vaccinated.

The opening of the “calving” is a decisive step in the fight against the disease

The form of vaccination that overcame these shortcomings was “calphism”. His discovery was a real breakthrough in development. In vaccinia, the fluid inoculated into the skin of healthy individuals was obtained from the bladders of cows infected with a virus related to the smallpox virus, which does not cause serious disease in humans, but activates immunity against smallpox. This invention was based on the observation that people who came into contact with “cowpox” were then thought to develop protection against smallpox. The English physician Edward Jenner made detailed observations and experiments, which he published in 1798. The new method, “vaccination” (vacca = cow), as Jenner called it, or “damalism”, as it was translated in Greek, spread at an impressive rate. speed. The first publication in Greek “on the use of damalido” appeared in 1805. It is interesting that in many Latin languages ​​the meaning of the term “inoculation” was later expanded to include vaccination in general, despite the absence of any connection of vaccines against other diseases with … cows.

The origin of the cow virus vaccine has been a source of controversy and vaccine rejection for many years, even though the survival benefits of cow breeding have been significant and documented. Today we know that, ironically, the virus that formed the basis of smallpox vaccines, which was called “cowpox virus”, is different and phylogenetically closer to the virus “vaccinia” (cowpox), “equine pox” (horsepox ).

The spread of pastoralism led to a gradual decline in the incidence of smallpox during the 19th and 20th centuries, during the first half of which the disease gradually ceased to be endemic in Europe and North America. In Greece, the last endemic cases appeared in 1944. However, imported cases and epidemic outbreaks around them continued to appear and required high levels of vaccination in all countries. The implementation of the principle “no one is safe if everyone is not safe” played an important role in the creation of the great smallpox eradication program in the 1960s and 1970s.

Unfortunately, in the era of the COVID-19 pandemic, the important legacy of the above principle has been overshadowed by other priorities and interests: by the end of November 2022, 75% of the population in high-income countries had completed core COVID-19 vaccination, while this percentage was 20% in low income countries! Let’s learn from the eradication of smallpox: the fight against global inequality is not only the highest moral requirement, but also a condition for effective fight against infectious diseases.

Mr. Takis Panayotopoulos is Professor Emeritus of Public Health – Child Health at the former National School of Public Health.

Editor: Evantis Chatsivasiliou