Researchers suggest cholera vaccination strategies for Zimbabwe

by Claudia Adrien

Mathematical models analyzing how a cholera outbreak spread in Zimbabwe are providing new insights into the most effective vaccination strategies for preventing future cholera epidemics, according to University of Florida researchers.

The mathematical models employed to analyze a large in Zimbabwe in 2008-2009 suggest that mass vaccinations deployed strategically could prevent future epidemics in that country and others.

The researchers' findings, published online in late April in the , provide a tool for aid agencies in Zimbabwe and in other nations prone to cholera to deliver treatments more cost-effectively.

"We wanted to know where the hot spots of the outbreaks were occurring, and we needed to factor how many people one sick person could potentially infect," said the paper's lead author, Zindoga Mukandavire, a postdoctoral associate from Zimbabwe with an appointment at UF's Emerging Pathogens Institute.

To find answers, the UF-led research team examined how cultural, political and economic factors influenced routes of cholera transmission. Cholera is a caused by a bacterium that affects the human intestinal track and an afflicted person may experience days of diarrhea and dehydration, which can lead to death.

The cholera bacterium is not native to the natural environment of Zimbabwe and researchers think it was imported from neighboring nations during the 1970s. During the 2008-2009 , nearly 100,000 people were sickened and 4,300 died. UF researchers estimate the majority of those cases were the result of human-to-human transmission.

Researchers looked closely at cultural and other practices that might contribute to the spread of the epidemic. In order to account for regional differences in such factors, the researchers tracked weekly cholera incidence rates for each of the country's 10 provinces.

One practice that stood out was funeral feasts, which are common in Zimbabwe and other African countries. At these feasts, people often eat in a communal fashion, and it is also customary to shake hands with the bereaved, who may have been infected as they cared for the deceased under unsanitary conditions. The bodies are often transported from towns and cities for burial in the rural areas.

"Cholera transmission through these types of direct contacts among people accounted for much of the observed illness," said Dr. J. Glenn Morris Jr., director of the UF Emerging Pathogens Institute and an author of the paper. "There were also striking differences in transmission patterns from province to province, reflecting differences in environment, socio-economic conditions, and cultural practices."

The country's economic meltdown during the study period likely contributed to cholera outbreaks. As the public health system and infrastructure collapsed, burst sewers and unprotected wells lead to contaminated drinking water. In addition, the economic crisis made life-saving oral rehydration medication financially unaffordable for many Zimbabweans afflicted by cholera.

The differences observed among provinces suggest that approaches to disease control should be tailored to specific regional characteristics. For example, different areas may require different rates of vaccination to control the disease, potentially resulting in cost savings in less severely affected regions.

add to favorites email to friend print save as pdf

Related Stories

New technique may help quell cholera outbreak

Mar 31, 2011

A new technique honed by University of Florida scientists can track rapid molecular changes that occur in cholera strains during epidemics and researchers hope the genetic analysis will help stamp out such outbreaks.

Cholera in Africa spreading at 'alarming' rate

Sep 30, 2010

(AP) -- An alarming number of new cholera cases have been reported in the West African nations of Cameroon, Chad, Niger and Nigeria, an international aid agency said Thursday.

Cholera vaccine could protect affected communities

Nov 27, 2007

A vaccine used to protect travelers from cholera, an infection characterized by diarrhea and severe dehydration, could also be used effectively among those living in cholera-prone (endemic) areas, according to a research ...

Cholera outbreak reported in Namibia

Mar 12, 2008

Health officials in Namibia say one person has died in a cholera outbreak in the Engela Health District, which has been compromised by floods.

Recommended for you

Two expats die of MERS in Saudi commercial hub

13 hours ago

Two foreigners died of MERS in the Saudi city of Jeddah, the health ministry said Saturday, as fears rise over the spreading respiratory virus in the kingdom's commercial hub.

UAE reports 12 new cases of MERS

13 hours ago

Health authorities in the United Arab Emirates have announced 12 new cases of infection by the MERS coronavirus, but insisted the patients would be cured within two weeks.

Filipino tests negative for Middle East virus

Apr 19, 2014

A Filipino nurse who tested positive for the Middle East virus has been found free of infection in a subsequent examination after he returned home, Philippine health officials said Saturday.

User comments