The lucky ones: Australian schoolchildren being immunised in the 1950s.
T he global effort to eradicate polio, a disease that has been on the brink of extinction for years, is facing serious setbacks on two continents. The virus is surging in Somalia and the Horn of Africa, largely free of cases for several years. And a new outbreak has begun in a part of Pakistan that a warlord declared off-limits to vaccinators 14 months ago.
The African outbreak began in May with two cases of polio paralysis: one in Mogadishu, Somalia's capital, and another in the huge Dadaab refugee camp in Kenya, where thousands of Somalis have fled fighting between Islamic militants, clan militias, government troops and African peacekeepers.
Now there are 121 cases in the region; last year, there were only 232 in the world.
The new Pakistan outbreak is in North Waziristan, near the frontier with Afghanistan. It is in an area where a warlord banned polio vaccinations after it was disclosed that the CIA had staged a hepatitis vaccination campaign in its hunt for Osama bin Laden. The warlord, Hafiz Gul Bahadur, banned all efforts until US drone strikes ended.
Although only three North Waziristan children have suffered polio paralysis since then, even one case shows that the virus is in the area and could spread.
The new outbreaks may delay a recently announced $5.5 billion plan to eradicate polio by 2018. Nonetheless, public health officials still believe that, with enough local political will and donor money, they can prevail by using techniques that have worked before.
To prevent the disease from reaching Mecca during next month's haj, the Saudis have tightened their rules. Pilgrims from any country with polio cases must be vaccinated at home and again on arrival. Last year, nearly 500,000 pilgrims were vaccinated on arrival, Dr. Ziad A. Memish, the Saudi deputy health minister, said recently.
The Pakistan outbreak is particularly frustrating, because eradication had been going steadily forward despite the killings in December of nine vaccinators that some blamed on the Taliban.
Public health officials had counted themselves lucky that despite simultaneous vaccination bans in North and South Waziristan, no polio virus was known to be circulating in the 250,000 children in those areas. Vaccination posts were set up on nearby highways and on buses and trains. Urban hospitals packed vaccine on ice for families willing to smuggle it back to neighbours, but it was not enough.
''The equation is simple,'' Dr Elias Durry, emergency co-ordinator for polio eradication in Pakistan for the World Health Organisation, said. ''Where you can immunise, the virus goes away. Where you can't, the virus gets in.'' Durry said he hoped that parents whose children were paralysed would speak up at local decision-making councils, called shuras, that are common in tribal areas, and possibly put pressure on warlords to rescind the ban.
The Taliban warlord in South Waziristan, Maulvi Nazir, was killed by a drone strike in January.
Before the Waziristan outbreak, Pakistan had seen only 24 cases this year, about as many as it had at the same point in 2012. Most were around Karachi and Peshawar, where last year's killings of vaccinators took place and where resistance to vaccines is highest.
The Somali outbreak is different. There is little opposition to the vaccine, said Dr Bruce Aylward, the WHO assistant director general for polio. In several Muslim countries, including Pakistan, the drive has been hurt by rumours that the vaccine sterilises girls or contains pork products or the virus that causes AIDS.
However, he said, many cases are in areas south of Mogadishu where the militant group al-Shabab operates. The group opposes mass campaigns because it believes the sight of thousands of vaccinators going house to house would undercut its claim to rule those areas.
Instead, the campaign negotiates with local chiefs and mid-level Shabab members to hold small drives. Other tactics have changed too: Children of any age, and sometimes adults, get the drops, and drives are held twice a month instead of every three months.
Refugee camps face other obstacles. Large ones often have lawless areas on their fringes where vaccinators may fear to work.
''When this started, I said, 'Brace yourself for hundreds of cases','' Aylward said, because he knew that few children born in the last five years had been immunised. Still, he said he believed this outbreak could be beaten because it echoed the one that plagued the region from 2005 to 2007. It also began in Mogadishu, and it spread as far as Yemen and Eritrea and paralysed about 700 children before multiple mass vaccination rounds snuffed it out. Kenya, Yemen and Ethiopia are already planning those with help from Geneva.