“We are still far from an epidemic,” notes epidemiologist Renaud Piarroux

Two confirmed cases and the same call for vigilance. In Reunion, a person who had traveled to India contracted cholera. This was confirmed by the Regional Health Agency (ARS) on Thursday March 21. Two days earlier, in Mayotte, more than 1,400 km away, a first case had been confirmed by the prefecture. It was a person coming from the neighboring Comoros and arriving clandestinely in the Mahorais archipelago, according to the same source. “State services are fully mobilized”assured the Minister Delegate for Health, Frédéric Valletoux, before the senators. Should we be worried about these recently reported cases? Franceinfo interviewed epidemiologist Renaud Piarroux, cholera specialist.

Franceinfo: What is cholera? Can we still die from it today?

Renaud Piarroux: Cholera is a diarrheal disease. The microbe causing the pathology is called vibrio cholerae and causes diarrhea and vomiting. If they are very significant, this can cause major dehydration in certain patients and put their vital prognosis at risk. But this doesn’t happen in all cases, fortunately.

Theoretically, it is a disease that is very treatable. The problem with cholera is to rehydrate patients in time, by simply giving them rehydration solutions to drink, composed of water, salts and sugar in adequate doses. When dehydration becomes more severe and vomiting prevents oral rehydration, the rehydration solution must then be injected via an infusion.

“By doing this, more than 99% of patients are treated within a few days, without having any after-effects.”

Renaud Piarroux, cholera specialist

at franceinfo

On the other hand, if the patients arrive too late, there is no access to care or if the health centers are poorly equipped or do not have intravenous rehydration fluids, cholera can be fatal. What is very frightening for populations affected by this disease is how quickly, in some cases, it can kill a patient.

How to explain that these cases were recorded in Mayotte and Reunion ?

The case of Mayotte can be explained by the outbreak of cholera in the Comoros, which are a few dozen kilometers away, more precisely on the island of Anjouan. As for Reunion, it is another origin since it is a person who traveled. It is therefore a simple coincidence, which reflects the fact that cholera is still not under control worldwide.

Is this the first time that the two islands have faced this disease?

No. This has already happened in Reunion, where there has already been one case in 2022. For Mayotte, it is also very likely because the archipelago is located close to that of the Comoros, which has faced several waves of cholera over the last fifty years.

Is there a risk that the disease will spread within the two islands?

It is normal to be worried, but we are still far from being faced with an epidemic. Epidemic outbreaks are mainly caused by the ingestion of contaminated water or contaminated food by patients, sometimes by poorly secured funeral ceremonies.

“In Reunion, the situation does not seem to pose a problem and the risk of epidemic spread seems very low to me.”

Renaud Piarroux, cholera specialist

at franceinfo

In Mayotte, on the other hand, there is a little more concern, to the extent that there is a water supply problem, with regular water cuts, and populations who are in poor housing conditions precarious. We need to be much more vigilant. Despite this, in my opinion, we are not in the same circumstances as in the rest of the Comoros archipelago, faced with many cases of cholera, and which encounters even more problems with access to water.

How to react to avoid an epidemic?

The challenge is to take the problem seriously, even if there are only a few cases. Action must be taken very quickly to prevent the disease from being transmitted around patients. They must be treated, isolated and taken care of contact cases. These are fairly basic things which, when done well, prevent the outbreak of epidemics. On the other hand, the more precarious the habitat, the worse the access to water and the more difficult the access to care – we can think of people who are in an irregular situation who could hesitate to seek care – the more the risk of cholera transmission is high.

Which regions of the world are particularly affected by the disease?

There are two main epidemic foci. The first is located in southern Asia, which corresponds to the case recorded in Reunion. The other is found in Africa, particularly in East Africa, which increases the risk of cholera passing from Tanzania to the Comoros, then Mayotte. There is therefore always a risk of being faced with imported cases.