US MERS Patients Did Not Spread Virus in Hospitals or Homes
This highly magnified picture shows the Middle East Respiratory Syndrome Coronavirus (MERS-CoV).
Credit: CDC/ Cynthia Goldsmith, Azaibi Tamin

Two people who traveled to the United States after contracting Middle East respiratory syndrome (MERS) do not appear to have spread the virus to their family members or the health care workers who treated them, according to the Centers for Disease Control and Prevention.

Last month, the CDC reported two cases of MERS in the United States — one in Indiana and one in Florida. Both patients had recently traveled from Saudi Arabia, taking multiple flights, before they were hospitalized for MERS shortly after arriving in the United States.

The CDC tested all family members and health care workers who had close contact with the patients, and found that none of these close contacts had an active MERS infection, and none had been infected with MERS in the past. [8 Things You Should Know About MERS]

These results "are reassuring," said Dr. David Swerdlow, a public health official who is leading the CDC's response to the MERS virus (known as MERS-CoV). "Today, the risk of MERS-CoV infection in the United States remains low, but it is important that we remain vigilant and quickly identify and respond to any additional importations," Swerdlow said.

The CDC also announced in May a third person suspected to have MERS, who wasa business associate of the Indiana patient, but this man turned out not to have been infected, later testing showed.

Public health officials have also contacted nearly everyone who traveled on airplanes or buses with the two patients, and at this time, none appear to be infected with MERS-CoV, the CDC said. However, the agency cautioned that the investigation is ongoing, and the situation might change with additional testing.

MERS is a respiratory condition caused by a virus that's only recently been seen in humans. Symptoms include fever, cough and shortness of breath. Cases of MERS first appeared in Saudi Arabia in September 2012, and the virus has since sickened more than 700 people worldwide, about 250 of whom had died, according to the World Health Organization. 

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