In an online post on March 25, the Food and Drug Administration (FDA) reported that it has added the injectable antibiotic rifampin, manufactured by Pfizer, Inc., to the list of drugs that are currently in short supply. The shortage of the drug used for TB treatment is expected to last until June and is being caused by a manufacturing delay. Although TB rates are at an all-time low in the United States, the shortage comes at a time when prevalence of the disease is increasing globally. In correspondence addressed to physicians on March 18, the drug manufacturer wrote that some vials of the medication may not meet specifications for drug potency, and had exhibited a change in hue from the expected red powder to brown or black. Pfizer stated that it was investigating the matter. According to CDC, in 2011 approximately 9 million individuals globally became infected with TB, and there were 1.4 million TB-related fatalities.