The power of vaccines

Mothers in Pointe Noire know the value of vaccination. The port city, the second largest in the Republic of the Congo, was a tinderbox of cramped living conditions and poor sanitation when polio came calling in October 2010. The virus, a strain that had threaded its way from India to Angola, before creeping north to Congo, blazed its way across the city with ruthless efficiency as vaccination workers raced to snuff it out. The epidemic killed 180 people in Pointe Noire and the wider area of Kouilou, and left hundreds more paralysed.

Polio usually strikes in young children, killing between 5 and 10 per cent of those it paralyses. Pointe Noire’s victims were largely unvaccinated young men, the legacy of decades of bloody war and a failed healthcare system. Together they formed part of a parched underbrush that was ignited by the virus, and fed its path through the city. The case fatality rate was 40 per cent. 

“The virus is very, very good at finding victims,” says Sona Bari, spokesperson for the Global Polio Eradication Initiative (GPEI) in Geneva. “Polio can circulate silently for long distances and it can spread very easily. Immunisation is our best defence against it.”

Vaccines are an elegant science. They mimic disease agents to stoke the body’s critical immune response, priming it to attack if it encounters the pathogen again. They are, without question, among the world’s most cost-effective health interventions, all but wiping out some of man’s most feared plagues. From measles to mumps, whooping cough to diphtheria, immunisation has saved millions of lives, often at the cost of just a few dollars a dose.

As recently as 1988, polio was on the march in more than 125 countries, attacking 350,000 people each year. Today, the virus has been beaten back into just three: Afghanistan, Pakistan and Nigeria. Eradication is tantalisingly within reach: in 2012, there were fewer than 225 cases of polio worldwide.

Still, immunisation is a geographic lottery. The world’s poorest nations remain convulsed by diseases that have faded from memory in the West. Vaccines may be a silver bullet but unaided, fragile states such as Afghanistan and Yemen lack the funds to buy them and the medical infrastructure to distribute them.

Drug companies, for their part, can’t count on demand from single, cash-strapped nations being large and predictable enough to cover their costs.

Children pay the price of this disparity. Of the 430 people who died of measles each day in 2011, 95 per cent lived in poor countries. Most were under-fives. 

“If you go back to 1990, there were 12 million kids dying before their fifth birthday,” says Chris Elias, president of the global development programme at the Bill & Melinda Gates Foundation, the world’s largest private philanthropic organisation. “Right now we’re at 7 million. About 1.5 million of those deaths... are preventable by vaccine.”

Bridging this gap falls in part to the Gavi Alliance, a group of scientists, state leaders, philanthropic organisations and more, whose goal is to innoculate children in poor countries. The charity provides funding to buy vaccines in nations whose gross national income per capita is $1,550 or less, paired with grants to bolster their often patchy health infrastructure.

This is not hands-off aid. Countries are forced to co-finance vaccination drives, even if this means paying as little as $0.20 a dose, a sum that edges up in parallel with their income.

There is also pressure to show how and where cash grants are spent, and to stay on top of vaccine monitoring. By the time a country graduates from Gavi funding, it should be able to pick up the cost of the campaigns itself.

“The cost of the vaccines becomes absorbed into the budget over time,” says Dr Seth Berkley, CEO of Gavi. “It can be a matter of political will – will countries choose to put their money into vaccines, versus other things. But they certainly have the capability.”

Gavi can count its progress in lives saved. Since its launch in January 2000 with a $750m grant from the Gates Foundation, the charity has inoculated 370 million children and averted more than 5.5 million future deaths. Of the $4.3bn in aid it has doled out, nearly half has been funnelled into taming diseases in Organisation of Islamic Cooperation (OIC) member states.

In Yemen, the poor relative of the Arabian peninsular, the payback has been dramatic. The country has one of the highest rates of under-five mortality in the world, with 77 deaths for every 1,000 live births. In 2011, its inoculation coverage rate for DTP3 – a trio of doses of diphtheria, tetanus and pertussis vaccines meted out to infants, and a standard measure of immunisation – hit 81 per cent. Globally, the coverage rate is 82 per cent. 

Pakistan is the most demanding of Gavi’s wards, mopping up nearly $500m in aid. Vast and unstinting effort has driven its vaccination coverage rate from 58 per cent in 1999 to 80 per cent, snapping at the heels of the global average.

It was the first South Asian country to roll out the pneumococcal vaccine, helping to protect babies against the fatal bacterial infections that account for almost a fifth of Pakistan’s child deaths. At less than $4 a shot, says Berkley, it’s a sliver of the amount invested regionally in conflict.

“Many of our countries are important in the sense of the OIC, and obviously many have instabilities related to politics and conflict,” says Berkley. “This is an opportunity to invest relatively small amounts of money compared to what’s being spent on war and anti-terrorism, that could really help the development of the country.

"These are really good investments in trying to stabilise a region which is now somewhat unstable,” he adds.

Vaccines are just one piece of the puzzle. Ferrying them from factory to field requires a vast army of health workers and volunteers, foot soldiers in the war on disease. From Afghanistan to South Sudan, they fan out across villages and slums, going house-to-house with boxes of vaccine vials packed in ice. 

In rural areas, workers can be pitifully scarce, raising the risk of children in remote communities falling through the net. The gunning down of nine vaccinators in Nigeria in February, just months after the drive-by murders of eight field workers in Pakistan, is a sharp reminder of the dangers threatening those on the front line. 

“It’s one of the biggest challenges we face,” says Dr Mahendra Sheth, regional health advisor for Unicef. “We don’t have enough workers in rural areas. In others, it is only socially acceptable to use female workers, which can limit recruitment.”

To fill the gaps, aid agencies must be creative. In India, yellow-vested vaccinators board moving trains to find children without the inky dot on their finger that denotes a recent immunisation. In Pakistan, field staff camp out at highway tollbooths for buses, to intercept kids with migrant families. Health workers in the central African state of Chad seek out vets: when nomads bring their cattle for attention, they vaccinate their children.

For groups such as the World Health Organisation (WHO) and Unicef, the work to find these elusive pockets of children is complex and ceaseless.

“There are thousands of communities that don’t exist on any official count,” says Bari. “The virus is better at finding children than we are in these places.”

Aid agencies must keep the pressure on. In areas where fighting or political turmoil have halted inoculation programmes, disease strains can move fast, reversing hard-won gains. War-torn Iraq, whose public health system was once the envy of the Middle East, today has a lower vaccination coverage rate than Yemen.

“It’s not just about vaccinations: the coverage needs to be sustained,” says Sheth. “It’s the ongoing programmes that really make the difference at a national level.”