Here are some of the latest health and medical news developments, compiled by editors of HealthDay:
Waterborne Parasite Causing Illness and One Possible Death in North Texas
Outbreaks of a nasty parasite infection in public swimming places in Dallas and Fort Worth have local health officials increasing the chlorine content in many pools in order to control the outbreak.
According to the Dallas Morning News, 123 cases of cryptosporidiosis (also known as Crypto), an infection caused by the parasite Cryptosporidium have been reported in the greater Dallas-Fort Worth area since June. The death of a six-year-old girl is being investigated to see if she was a Crypto victim, the newspaper reports.
According to the U.S. Centers for Disease Control and Prevention, cryptosporidiosis is the most common waterborne illness in the United States. It is spread through contact with fecal matter, and the parasite can live in the human intestine for long periods of time. Symptoms include cramping, diarrhea, nausea and vomiting.
Dallas-area health officials have recommended that people with compromised immune systems not swim in public pools, the Morning news reports. And, says the newspaper, many municipalities are "hyperchlorinating" their public swimming facilities in an attempt to deter Cryto's spread.
Reintroduced MS Drug Cited in Two New Deadly Infections
Two new instances of a dangerous brain infection have been reported among users of Tysabri, a multiple sclerosis drug that was reintroduced two years ago after being pulled from the market because of the same adverse effect.
While the two new cases occurred in Europe, they raised international concern about Tysabri and its connection with the viral brain condition called progressive multifocal leukoencephalopathy (PML). The new cases were confirmed this week, according to the Bloomberg news service, which cited a statement from one of the drug's makers, Massachusetts-based Biogen Idec Inc.
Biogen and co-maker Elan Corp, based in Ireland, voluntarily withdrew Tysabri in February 2005 after three users contracted PML and two of them died. The drug was reintroduced in July 2006.
A Biogen spokeswoman told Bloomberg that additional cases had been anticipated and that pulling the drug again was "not under consideration."
Some 31,800 people were taking Tysabri at the end of June, and the companies had hoped to have 100,000 users by 2010, the news service said. The drug also has been approved in the United States to treat an inflammatory bowel disorder called Crohn's disease.
Of the two new cases of PML, one is recovering at home and the other has been hospitalized, Bloomberg said.
"These incidents of PML are unfortunate and disappointing, and we hope for the best possible outcomes for these individuals and their families," the National Multiple Sclerosis Society said in a news release. "However, their occurrence is within range of the predicted frequency of cases, estimated by a published report and by the FDA, of approximately one in 1,000 people taking the drug."