Anxiety as flood, others spike cholera outbreaks globally

Record cholera outbreaks around the globe, driven by drought, flood and armed conflicts, have inflicted hundreds of thousands of people and severely strained the supply of vaccines to the extent that global health agencies are rationing doses, according to a report published yesterday by New York Times.

Outbreaks have been reported in the Caribbean, Africa, the Middle East and South Asia, putting the health of millions at risk and overwhelming fragile health systems. Untreated, the disease, which is commonly spread through contaminated water, can cause death by dehydration in as little as one day, as the body tries to expel a virulent bacteria in gushes of vomit and watery diarrhoea.

Leader of WHO’s cholera response, Dr. Philippe Barboza, said: “The situation is very concerning, very worrying. We have had to worry about war and poverty and population movements, and that has not changed. But now we have climate change on top of that.”

In Nigeria, floods have displaced a million people in recent weeks and there are at least 6,000 cases of cholera. Latest figures from the Nigeria Centre for Disease Control (NCDC) suggest that a total of 10,745 suspected cases, including 256 deaths, with a case-fatality ratio of 2.4 per cent, have been reported from 31 states in 2022.

NCDC said there was 42 per cent increase in the number of new suspected cases in September (4,153) compared with August.

The authorities in Kenya are reporting suspected cholera in people fleeing violence in Somalia and arriving at the mammoth Dadaab refugee camp, where tens of thousands of children are at risk.

In Haiti, cholera has broken out as whole neighborhoods of people displaced by violence are packed into small open patches in Port-au-Prince, sharing a single cracked pipe of water that runs through untreated waste. The disease is also festering in the country’s overcrowded prisons.

In Syria, millions of people displaced by civil war lack access to clean water, while the years of fighting have destroyed sanitation infrastructure. Raw sewage is being pumped into the Euphrates River, which hundreds of thousands of people depend on for water. The United Nations reports more than 20,000 suspected cholera cases and 75 deaths there.

In Pakistan, where a third of the country is fully under water after massive monsoon flooding and close to 10 million people have been displaced, there are reports of cholera cases in a dozen locations. These are not yet full-blown outbreaks and vaccination could help stave off disaster.

But demand for vaccination is so high that WHO has suspended the recommended two-dose vaccination regimen and switched to a single dose, in an effort to stretch supply and respond to more outbreaks that could occur in the coming months.

“We have never had to make a decision like this about vaccination before. That’s the severity of this crisis,” Barboza said.

If enough single doses are given in a region, it should be enough to quell an outbreak, she said.

But the length of protection is significantly shorter. A single dose of the vaccine gives between six months and two years of immunity, while a full regimen of two doses delivered a month apart gives adults four years of protection, Barboza added.

If a second dose could be delivered within six months, it should give three years of protection. But evidence on the exact duration of protection is limited. It is known to be much shorter in children.

WHO said some 36 million doses of oral cholera vaccine were expected to be produced in 2022, and of the figure, 24 million have been shipped for vaccination campaigns. Eight million doses have already been designated for a second round of emergency vaccination in four countries namely Cameroon, Malawi, Pakistan and Kenya.