The US army is ruling out biological or chemical weapons as the source of a wave of cases of pneumonia among troops in Iraq, according to the Pentagon.
Figure 1.
US troops before a raid in Iraq
Credit: EPA/PA
From 1 March to 30 July about 100 cases of pneumonia were reported among US soldiers deployed in Iraq and other countries in the region, and military doctors have not been able to determine the cause of the disease in most of the cases. There is no evidence that the disease has been passed from one person to another.
In 15 of the cases the pneumonia was severe enough to require intubation. Ten of those cases occurred in Iraq, where most troops are deployed. The others occurred in Kuwait, Qatar, and Uzbekistan. Two soldiers have died, both of whom served in Iraq. No British troops have been affected by the illness, according to the Pentagon.
The army has assigned two teams of medical investigators to determine the cause of the pneumonia. Epidemiologists investigating the illness are focusing on environmental factors such as dust and dehydration, as they have ruled out severe acute respiratory syndrome, legionnaires' disease, anthrax, smallpox, and other infectious agents as a cause of the illness.
The pneumonia is said to resemble an inflammatory reaction. Army doctors have speculated that it is the result of irritation, perhaps from dust. Soldiers who smoke local Iraqi cigarettes that lack filters are believed to be at highest risk of developing the pneumonia.