On Friday, India marks a huge public health milestone – a year since a case of polio was found in the country – a critical step in being declared polio-free and an achievement that many experts long argued was impossible.
Just two years ago, India reported 741 cases of polio, the largest number in the world. But a mammoth, years-long push, involving billions of dollars and millions of volunteers fanning out across the country's rural villages and slums to vaccinate children has paid off. It has been a full year since a case was found, allowing the World Health Organization to declare polio is no longer endemic here and transmission has been stopped.
(It will take two more years without new cases before polio is technically considered eradicated.) "I feel like, 'Am I awake? Is this real? Can it be true?'" said Lieven Desomer, who heads the Unicef polio eradication unit in India. "If you look at the size of the country and the complexities and challenges they have had to overcome over the years – it's truly hard to believe."
Polio now remains endemic in only three countries: Pakistan, Afghanistan and Nigeria. It is still considered present in three other countries (Chad, Angola and Congo) where the virus was reintroduced after eradication had been achieved.
"The importance of India can't be overstated," said Hamid Jafari, who heads the WHO team here. "This establishes beyond doubt that ... it is possible to stop transmission even in extremely challenging conditions. And India was one of the two major sources of international spread of virus so going forward, if this progress is sustained in India, it will no longer be a source of international spread."
The WHO used genetic testing to establish that the strain of polio that was reintroduced to Congo and Angola came with a traveller from India.
Polio was controlled in much of India a decade ago, but in the poorest states of Uttar Pradesh, West Bengal – and Bihar, where fewer than 10 per cent of people have access to sanitation facilities – the virus lived on and spread from population reservoirs until last year. Many international public health officials said that given the low rates of childhood vaccination coverage, the poor access to sanitation and clean water, and widespread malnutrition (which causes low immunity), it would be impossible for India to stamp out polio now or any time soon.
But the Indian government and its great champion, software tycoon Bill Gates, among others, disagreed. About four years ago high-powered partnerships began to form with the country and Mr. Gates, who called the ambition his "number one priority" and whose foundation has put in hundreds of millions of dollars. And the WHO, Unicef and Rotary International are equally engaged. India itself poured $1.2-billion into the almost unfathomably large public program to vaccinate children and to monitor water, sewage and sick kids in high-risk areas.
To date, the Indian government has spent more than $1.2-billion on domestic polio eradication activities. Globally, Rotary members to date have contributed more than $1-billion in support of polio eradication. In all, about $136.67-million in Rotary money has funded polio eradication work in India via grants to WHO and UNICEF. Indian Rotary members have raised more than $11.6-million to fight polio.
Children in many parts of India don't get routine vaccinations – but the government has focused on repeated polio vaccine blitzes, trying to catch every single child in one or two days. In each of two rounds last year, 172 million children were given oral polio vaccine by 2.5 million yellow-vested volunteer vaccinators. Those vaccinators go door-to-door, as in other countries, but also ride trains and buses and camp out at busy crossings and borders, to catch the low-income migrant populations who have carried the disease in the past. India also put money into developing a new vaccine that would target the strain of polio persisting here.
The challenge now, Dr. Jafari said, will be to maintain vaccination levels and surveillance. Because routine vaccination rates remain below 80 per cent in some states India is at grave risk from an "importation" that will reintroduce the virus – and the lesson from other countries is that this end-game phase of eradication can bring painful setbacks.
Deepak Kapur, chair of the Indian polio project for Rotary International – the biggest private financial supporter and provider of volunteer hours to the polio fight – said he is frankly worried by the festive mood here. "The moment we have any kind of celebration it would send wrong signals – money will not flow into the program, political will will flag, bureaucracy will say it's done – and we would have to begin at square one if virus finds its way in again. One virus coming in and catching hold where a number of children are not so well vaccinated and you are going to have a conflagration and this $8-billion invested worldwide and millions of person hours will be in vain."
Progress toward polio eradication in Afghanistan and Pakistan, meanwhile, is limited: the security situation in both countries complicates the efforts, while in Pakistan the image of the program has suffered because the United States Central Intelligence Agency reportedly used volunteer polio vaccinators to collect data in its surveillance of Osama Bin Laden.
Other eradication efforts
Smallpox is the only infectious disease that has been eradicated in humans. A vaccine against the viral disease was developed in the 18th century, but smallpox flourished in conditions of poverty. Eradication efforts began in 1967 and the battle against the disease was won in 1979.
There is currently one other disease being targeted for eradication, dracunculiasis (guinea worm disease.) It is caused by a parasitic worm ingested from unclean drinking water and is found mainly in sub-Saharan Africa. The infection causes searing joint pain and worms can burrow through the skin. The eradication campaign began in 1986 and is about 99-per-cent complete, but like polio, finishing the job is proving difficult.
Aborted global programs to eradicate diseases
* Yaws: A disfiguring, crippling bacterial disease. An eradication campaign began in 1952, inspired by the availability of a cheap treatment, penicillin. But the conditions that allowed the disease to spread like overcrowding and poor sanitation were not addressed. The campaign was dropped in 1964.
* Malaria: A potentially fatal parasitic disease that is transmitted by mosquitoes. A global eradication campaign was launched in 1955. It consisted primarily of spraying with DDT which had unintended consequences like mass deaths of wildlife and poisoning of water supplies. The campaign was abandoned in 1964.
Five infectious diseases that could be eradicated
* Measles, mumps, and rubella (also known as German measles), all viral diseases common in children.
* Lymphatic filariasis (elephantiasis), a parasitic disease.
* Cysticercosis (pork tapeworm), disease caused by parasite.
Source: The Carter Center International Task Force for Disease Eradication