Six people have died from the acute diarrhoeal disease in the past two weeks after the floods left tens of thousands of people stranded in camps with few toilets and little clean water.
Health workers are now battling to carry out a mass vaccination in the storm-hit city of Beira following a delivery of nearly 900,000 doses last week.
It has been described as “the most ambitious campaign ever conducted using the one-dose oral cholera vaccine strategy” by the humanitarian organisation Doctors Without Borders.
The UN specialist coordinating the relief effort, Julien Graveleau, said he was “quite optimistic” of success despite the challenges.
“Of course, the numbers will be increasing but I believe we’re ready for it,” he added.
Mozambique’s health ministry said that more than 70 per cent of the vaccines had been administered by Sunday morning, partly thanks to megaphone-wielding promoters handing out doses in busy streets in Beira and elsewhere.
At the city’s popular Shoprite grocery, people knocked back the doses like shots in a bar and walked on.
“We were prepared really for the worst,” said Francisca Baptista da Silva, a project coordinator for Doctors Without Borders. “But for the moment we are controlling it.”
Outside one cholera treatment centre in the Beira neighbourhood of Pioneros, a woman sold bottled water while passersby stepped carefully around fetid pools of water in the street.
“It’s a big problem,” said Rosa Zimbane, who reported herself healthy so far, as an ambulance arrived carrying two women with small children.
Treatment for cholera can involve simple rehydration but the disease can kill within hours and more severe cases need intravenous drips.
Inside the centre more than a dozen people lay on beds with two buckets at the ready. One was for vomiting.
Dr Katrien Duquet, also of Doctors Without Borders, said that they had seen fewer cases of cholera than expected overall.
“It never spiked to the level we thought,” she said. “But people are still afraid of cholera. We are not claiming this is over.”
In the village of Bopira more than 1,300 people have been drinking from the local pond and other muddy pools left behind by Cyclone Idai.
The vaccine is normally given in two spaced-out doses but a single dose, which offers six months of coverage, is effective in emergencies, according to the charity.
At least 847 people have been reported killed by Cyclone Idai and the associated flooding across Mozambique, Zimbabwe and Malawi since it made landfall in Beira on 14 March. More than 3 million people have been affected, mostly in Mozambique.
Additional reporting by agencies
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