20100415
allafrica

A new, multi-drug resistant strain of salmonella discovered in Africa is spreading and affecting the weakened immune systems of HIV positive individuals on the continent, according to a recent study. The study was conducted in Malawi by scientists from the University of Liverpool in the United Kingdom with the Wellcome Trust Sanger Institute and built on past research that ascertained that the African salmonella strain is quite aggressive and genetically resembles the strain of salmonella that causes typhoid fever.

Salmonella is a public health threat all over the world, and is often transmitted through bacteria in contaminated food. Salmonella found in developed countries causes diarrhoea, and is usually not dangerous for the average person. The type of Salmonella that causes typhoid fever is caused by bad sanitation and is more harmful and is found in less developed countries.

The study concluded that the bodies of HIV positive patients provide a good environment for Salmonella bacteria to grow because there are less immune cells to combat it. According to Dr. Melita Gordon, Senior Lecturer and Consultant in Gastroenterology at the University of Liverpool, who helped conduct the study, "the bacteria hide intracellularly in both the blood and bone marrow, and persist after the acute infection has resolved." The persistence of the bacteria makes the new strain invasive and quite dangerous, as it may develop more and more resistance to antibiotics through time and exposure inside the body.

Dr. Gordon explained that, although this new salmonella strain does not appear to have an impact on healthy adults, it can be dangerous for children and HIV positive individuals, killing one out of four people who contract it. "The new strain causes invasive disease in many African children who are not HIV positive, but are susceptible because they are very young, and have anemia or are malnourished." By Rebekah Mintzer