Why it’s difficult to pinpoint source of cholera

Searching for the cholera source is like searching for a needle in a haystack. 

This is according to Doctors Without Borders (MSF) regional medical director Dr Mounia Amrani, who has worked in the humanitarian field as a doctor for over eight years dealing with cholera outbreaks in different countries.

Amrani said it was common to have a cholera outbreak without finding the source as the bacteria does not stay long in water, especially in a river.

“Cholera can live for one to two weeks in moving water and a little bit longer in stagnant water. The bacteria does not contaminate an entire body of water, bits and pieces of it can live in parts of the water,” said Amrani. 

“There is a chance one might collect a sample from a body of water that contains particles of the bacteria but the sample you collected does not have the bacteria. So tests would not pick it up. You would be lucky to collect a sample that has the bacteria. 

“There is also a chance the virus had died by the time tests were conducted.”

The City of Tshwane and health department have not been able to find the source of cholera for two weeks.

The outbreak in Hammanskraal, north of Pretoria, has claimed the lives of more than 20 people.

Amrani, who was part of a team that recently aided several countries such as Zimbabwe, Mozambique and Malawi with containing cholera outbreaks, said the leading cause of outbreaks was often the inter-human spread of the bacteria.

She said while it was important to make sure that all water sources such as reservoirs and water tankers were cleaned, it was also pertinent for people to practise extra cautious hygiene by washing their hands regularly and boiling any water.

“It is much easier to detect it in a human being as it is highly concentrated, than it is to find in water. And because it is highly concentrated in a human being, it becomes highly contagious through their vomit and/or exposure to their faeces. 

“What we are seeing in Hammanskraal is that infections are taking place among the people, so it is not so much the source that is causing the outbreak, but people infecting each other.”

In theory, Amrani says you can find cholera in the soil, rivers and almost everywhere in the world but you would have a system of chlorination where the cholera is killed before the water is distributed to people.  

“The reason you get outbreaks of cholera in some places and not in others is that in some places you have a disruption of the water system such as floods which lead to the cholera finding a way into the water system,” Amrani said.

Hammanskraal families who have lost their loved ones as a result of the outbreak said they were still waiting in limbo for answers from authorities.

The families said stool samples were taken by officials from the department of health but no answers or responses have been provided.

“It is very disappointing because I don’t know if they forgot about us and forgot that they took samples and we deserve to know what caused the outbreak. I want to know what is happening,” said Kamo Stock, whose grandmother died two weeks ago.

“What is also infuriating is that the DA says the water is fine and they can't trace the source. We haven't used tap water for years, we only used it to flush the toilets and used the water from water tanks to brush teeth, cook and do other things so that might have been the cause. We deserve to know what is happening.”

The Mathosi family who suffered a double loss when died just days apart while their mother Constance was battling cholera in hospital said they too were still waiting for answers. Their dog also died.

Martha Mathosi said days before her mother was discharged from the Jubilee hospital health officials came to ask them questions about what they had eaten and whether they had recently travelled.

“...they [officials] also wanted to take samples from my sister’s son, Tshepo, who was hospitalised with the other three. But they never came back, this was two weeks ago,” she said.

sibiyan@sowetan.co.za