It was one of the deadliest diseases known to humans, and to date the only human disease to have been eradicated by vaccination.
Smallpox is an acute contagious disease caused by the variola virus, a member of the orthopoxvirus family. It was one of the world’s most devastating diseases known to humanity. The last known natural case was in Somalia in 1977. It was declared eradicated in 1980 following a global immunization campaign led by the World Health Organization.
Smallpox is transmitted from person to person via infective droplets during close contact with infected symptomatic people.
Prior to eradication, smallpox epidemics were common in many countries, leaving death, blindness and disfigurement behind. The eradication of this devastating, infectious disease has been called one of the greatest achievements in public health.
39 years ago today, a World Health Assembly resolution declared #smallpox eradicated.
It was one of the deadliest diseases known to humans, and to date the only human disease to have been eradicated by vaccination https://t.co/94zgn0e5lz#VaccinesWork 💪🏽 pic.twitter.com/FlYfvqHMMd
— World Health Organization (WHO) (@WHO) May 8, 2019
A reminder of the value of smallpox eradication
“The eradication of smallpox shows that with strong mutual resolve, teamwork and an international spirit of solidarity, ambitious global public health goals can be attained,” says Dr Margaret Chan, Director-General, WHO.
“The statue stands as a reminder of the significance of such an achievement, and shows the power of international health cooperation to do great and lasting good.”
The cast bronze and stone statue depicts four persons, one of whom is a girl about to be vaccinated in the arm. The statue pays homage to all those who were involved in the eradication drive, including governments, health care workers, donor agencies, non-governmental organizations, commercial firms, and village leaders who supported the vaccination of their residents and provided food and shelter on many occasions to vaccination teams.
Plaques surrounding the statue, written in the six official languages of WHO, state that this victory was made possible by all nations working together.
Smallpox eradication “stimulated us all to reflect not only on the eradication of one disease, but on how this experience can help us to attack more effectively other health problems with the same enthusiasm, optimism and sheer hard work that characterized the successful crusade against smallpox,” wrote Dr Halfdan Mahler, former Director-General, on the occasion of the signing of the document in 1980 that declared that smallpox had been eradicated.
“The statue’s focus is on the health worker’s hand who is performing vaccination with the recently invented bifurcated needle1. Vaccinators and field staff were the foundation of the programme,” said Dr Donald A. Henderson, Distinguished Scholar, Center for Biosecurity; Professor of medicine and public health, University of Pittsburgh Medical Center; and Distinguished Professor, Johns Hopkins School of Public Health.
A World Health Assembly resolution (WHA33.3), adopted on 8 May 1980, declared that the global goal of smallpox eradication had been achieved. The world’s last naturally occurring case was discovered on 26 October 1977 in Somalia; this was followed by two years of actively searching for cases to make certain that transmission of the virus had been stopped.
Eradication saves money
With the global eradication of smallpox, vaccination stopped and quarantine measures were no longer needed. Annual savings are estimated to be more than US$ 1 billion, above and beyond the alleviation of a terrible burden of death and disability. The total cost for the programme over the period 1967 to 1980 has been estimated to be about US$ 300 million of which two thirds was borne by the endemic countries themselves.
Eradication team members attend ceremony
Former WHO Director-General, Dr Halfdan Mahler; former Director of Smallpox Eradication at WHO, Dr Donald A. Henderson; members of the former Smallpox Eradication Committee; headquarters and regional WHO staff; statue donors; and individuals who participated on the ground in smallpox vaccination campaigns attended the ceremony.
The designer and sculptor of the statue is Mr Martin Williams, from Swansea, Wales in the United Kingdom.
Background on smallpox eradication
Over the centuries, smallpox has been one of mankind’s most feared and deadly diseases with a history dating back at least 3500 years. Historically, it spread across the world, killing kings and peasants alike. People in many countries worshiped special deities intended to protect them from smallpox. One third or more of infected people died, as little could be done for them.
The first vaccine
Hope for protection against the disease emerged in 1796. An English physician, Edward Jenner, discovered that by inoculating a person with pustules from the pox infection of a cow, smallpox could be prevented. The vaccinated person developed antibodies which protected both against the cowpox infection and against the closely related virus that caused smallpox. It was the world’s first vaccine.
For nearly a century, the vaccine virus (called vaccinia), was transferred from one person to the next – from arm to arm. The problem was to discover how to provide large amounts of vaccine. This was eventually solved by growing the vaccine virus on the flank of cows.
The practice of vaccination spread but it was much less effective in the tropical countries because the vaccine rapidly deteriorated in the heat. Finally, in the 1950s, an English scientist, Leslie Collier, discovered a method to produce a potent, heat-stable vaccine that could be used throughout the world. This was a pivotal development in the successful effort to eradicate the disease because it eliminated the cumbersome logistics required to maintain the cold chain for previously used liquid smallpox vaccines. Health care workers could carry the freeze-dried vaccine for 30 days in their bags and the vaccine would still be potent.
The bifurcated (two-pronged) needle, invented by a scientist at Wyeth Laboratory, permitted the development of a new vaccination technique called the “multiple puncture” method. It was easy to perform and required only one fourth as much vaccine as other methods in use. It soon replaced all other techniques for vaccination.
History of the global eradication programme
Since its founding, the World Health Assembly has been concerned about smallpox control. In 1948, at its first meeting, it was decided to form a joint study group on smallpox. During the next years, it supported research to compare the effects of different strains of smallpox vaccines and fostered efforts to improve vaccine production methods. In 1955, the 7th World Health Assembly decided to provide budgetary assistance to some governments and solicited donations of vaccine. Between 1959 and 1966, many countries provided supplies of vaccine, the USSR (Former Soviet Union) alone donated more than 400 million doses. However, progress was slow and vaccine shortages regularly occurred.
In 1966, the 19th World Health Assembly took the momentous decision to undertake a global programme of smallpox eradication, first initiated by the same body in 1959. In the Director-General’s Report to the 19th World Health Assembly, a new strategy was proposed and accepted with special funds authorized. An intensified effort to eradicate the disease began in January 1967. That year, there were more than 10 million cases and 2 million deaths in 43 countries.
The basic strategy consisted of two components: carefully monitored mass vaccination programmes to reach 80% of the population and a new approach to disease prevention — surveillance and containment. This required weekly reports of smallpox cases from all health units with special teams to quickly investigate cases and outbreaks.
As the programme progressed, smallpox was eliminated first in South America, West and Central Africa, then in Asia and finally in East Africa. Global smallpox eradication was finally achieved with the world’s last naturally-occurring case in Somalia on 26 October 1977. Special search programmes continued throughout the world for another two years to be certain that transmission had stopped. The World Health Assembly resolution (WHA33.3), adopted on 8 May 1980, declared that the global goal of smallpox eradication had been achieved.
Success factors
Continuing research, technical innovation, and adaptation of the programme strategy to local circumstances were critical factors in the success of the eradication effort. Innovations by programme staff that affected global programme policy included progressive innovations in the surveillance and containment strategy, the use of smallpox identification cards in markets and special house-to-house searches, and techniques for isolating patients in their homes, villages or in special compounds.
Epidemiological studies by field staff demonstrated that smallpox did not spread so rapidly as textbooks suggested. Thus, surveillance and containment worked more effectively than had been hoped. Vaccine immunity proved to be sufficiently long-lasting that repeat vaccinations were not necessary during the course of the programme.
-WHO.
