Scientists map cholera hotspots in Uganda to ease response

Tuesday January 16 2018

The study further found that the risk of having

The study further found that the risk of having cholera inside the hotspot districts was up to 22 times higher than elsewhere in Uganda. GRAPHIC COURTESY 

By EVELYN LIRRI
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A team of experts have mapped key cholera hotspots in uganda, helping plan for future control interventions.

The hotspots, which were mapped based on previous cases in the country, will also help in predicting where future outbreaks are likely to occur.

In a study jointly conducted by researchers from the Johns Hopkins Bloomberg School of Public Health, Makerere University College of Health Sciences and the Ministries of Health and Water, the experts collected and analysed data between 2011 and 2016, based on cases of cholera that had been reported across the country.

They also analysed data on rainfall, water, sanitation and hygiene patterns in order to identify high-risk areas prone to outbreaks.
In the period when the research was undertaken, 11,030 cases of cholera were reported in 37 of the 112 districts. Twenty of the districts experienced cholera outbreaks at least twice during the period.

The proximity

“We identified 22 districts as high risk for cholera, of which 13 were near the border of the Democratic Republic of Congo while nine were near the border of Kenya,” the researchers say in their report.

Because cholera is transmitted through contaminated water or food, the proximity of most of these countries to international shared lakes and the River Nile, and the higher annual rainfall in the hotspot districts, increase the risk of a cholera outbreak.

The study further found that the risk of having cholera inside the high-risk districts or hospots was two to 22 times higher than elsewhere in the country.

“In total, 7 million people were living within cholera hotspots,” the study shows.

Despite advances in science and technology for prevention, cholera remains a major public health problem in sub-Saharan Africa, as poor detection and treatment makes it difficult to effectively control the disease.

Cholera outbreaks

Since last year, Kenya, Malawi, Zambia, South Sudan, Somalia and the Democratic Republic of Congo have reported major cholera outbreaks.
Kenya’s Ministry of Health reported more than 3,000 laboratory-confirmed and probable cases of cholera in 2017 alone, while in Zambia, a prolonged outbreak of the disease, which started in October 2016 has led to more than 2,000 cases to date.

Dr Godfrey Bwire of Uganda’s Ministry of Health said identifying areas with increased risk is an important step in putting in place interventions required for prevention.

“In order to control a disease, you need to target your interventions to the most affected group and find out the factors that cause them to be at risk,” said Dr Bwire.

“Instead of targeting the whole country with interventions when an outbreak occurs, mapping helps you to target specific areas. In the long run, this is a much cheaper option.” he added.

Safe drinking water
He said that one of the interventions that the government is putting in place is increasing access to safe drinking water.
Uganda’s cholera prevention intervention is part of a global framework put in place by the World Health Organisation to end cholera as a public health challenge by 2030.

Control programmes
The researchers noted that the findings of this study could be used as a guide to strengthen the cholera control programmes in the region.
“Since a majority of hotspot districts are near the DRC and Kenya borders, collaboration with these countries would be an effective strategy for controlling cholera,” they said.
Dr Bwire concurs. “Even if we control cholera in Uganda but cases in neighbouring countries persist, we will no address the problem because of the cross-border movements,” he said.
The Ministry of Health says it will soon introduce the oral cholera vaccine in Uganda, targeting people in the hotspots who face an increased risk of being infected.