HARARE,  (IRIN) - Typhoid fever has killed five people in Zimbabwe's capital, Harare, and 30 others were being treated for the bacterial disease, the city's health director, Stanley Mungofa, told a media briefing on 9 March 2010.

The epicentre of the outbreak is the high-density suburb of Mabvuku. In the past two years the township has rarely experienced a reliable supply of water, forcing residents to dig shallow wells, which are easily polluted by ablutions and waste.

According to the World Health Organisation (WHO), "Typhoid fever is a bacterial disease, caused by Salmonella typhi. It is transmitted through the ingestion of food or drink contaminated by the faeces or urine of infected people."

Symptoms include high fever, headaches, constipation or diarrhoea, rose-coloured spots on the chest, and an enlarged spleen and liver, usually occurring from one to three weeks after exposure, and may be mild or severe.

The case fatality rate can be about 10 percent, but antibiotics can reduce this to below one percent. According to the Canadian Medical Association Journal, complications occur in 10 to 15 percent of cases, the most serious of which are "gastrointestinal bleeding, perforation and typhoid encephalopathy".

The five deaths in Harare were originally attributed to malaria, but subsequent medical investigation determined the cause to be typhoid. Water bowsers have been deployed in Mabvuku and "health promoters are moving door to door, emphasizing sanitation and hygiene, and establishing if there are new cases of typhoid," Mungofa said.

Cholera

Zimbabwe is still on alert for cholera - between September 2009 and January 2010, 149 cholera cases were recorded, resulting in five deaths. An epidemic of the waterborne

People can transmit [typhoid] as long as the bacteria remain in their bodies; most people are infectious prior to and during the first week of convalescence

disease began in August 2008 and lasted for a year before it was officially declared at an end in July 2009, causing the deaths of more than 4,000 people and infecting nearly 100,000 others. The fatality rate was also nearly 5 percent, much higher than the usual one percent.

In an outbreak of typhoid between September 2004 and January 2005 in the Democratic Republic of Congo, 42,564 cases of typhoid were reported, resulting in the deaths of 214 people.

"People can transmit [typhoid] as long as the bacteria remain in their bodies; most people are infectious prior to and during the first week of convalescence, but 10 percent of untreated patients will discharge bacteria for up to three months," the WHO website said. "In addition, two to five percent of untreated patients will become permanent, lifelong carriers of the bacteria in their gall-bladder."

Typhoid Mary

The ability of outwardly healthy people to carry the disease was first identified in 1907 by George Soper, a civil engineer hired by a New York banker to trace the origins of an outbreak during their family holiday.

Soper identified the cook, Mary Mallon, as the carrier - who became known as Typhoid Mary - after research into her employment history found that the incidence of typhoid fever had followed her through seven separate jobs.

Mallon was put into medical isolation in New York for a few years, before being released on condition that she did not work as cook again. However, she returned to the line of work a few years later and was discovered working under a pseudonym after another outbreak of the disease. Mallon thought to have infected at least 51 people over a period of about 15 years, of which three died.

WHO estimates that about 22 million cases of typhoid occur annually, causing 216,000 deaths, mainly in school-age children and young adults.

By IRIN