A second imported MERS-CoV (Middle East respiratory syndrome coronavirus) infection has been detected in the United States, in another health worker who had been living and working in Saudi Arabia and traveled to the states to visit family, officials from the US Centers for Disease Control and Prevention (CDC) and Florida announced today.

Identification of a second US case comes amid a steady rise in cases from Saudi Arabia and a report that the virus has killed another health worker in Jordan. Saudi Arabia reported 18 new cases, 3 of them fatal, today and over the weekend.

Second case bears similarities to first

The new US patient started having mild symptoms such as fever, chills, and a slight cough on May 1 on a flight from Jeddah to London, the first flight of a four-leg trip to visit family in the Orlando area, CDC officials said at a press telebriefing.

He sought care in the emergency department of an Orlando hospital on May 9 and was admitted. Florida health officials said the man was placed in isolation once MERS-CoV was suspected. The patient's sample tested positive at a Florida lab, with the finding confirmed by the CDC yesterday.

When asked about potential community exposures between the time the patient arrived in Orlando on May 1 and was hospitalized on May 9, John Armstrong, MD, Florida's state surgeon and secretary of health, said at the briefing that the patient remained in Orlando, did not visit any theme parks, and that health officials are tracing any other links. Florida media outlets said the man is 44 years old.

Antonio Crespo, MD, infectious disease specialist at Dr. Phillips Hospital in Orlando, said in a press release from the Florida Department of Health (FDH) today that the patient is in good condition and improving. "We are taking every precaution, but we believe the risk of transmission from this patient is very low since his symptoms were mild and he was not coughing when he arrived at the hospital." The hospital is a full-service 237-bed medical-surgical facility in southwestern Orange County.

Today's announcement of another MERS case in the US comes just 3 days after the first patient, a healthcare worker in his 60s, was discharged from a Munster, Ind., hospital.

At the briefing, CDC director Tom Frieden, MD, MPH, said that though the two cases are similar, there are no epidemiologic links between them. He said the patient hospitalized in Orlando worked in a hospital in Jeddah that has treated MERS cases, though it's not clear if he had cared for any of them. The health worker that was hospitalized in Indiana worked in a Riyadh hospital.

Recent hospital clusters of cases have occurred in both cities, and an expert team from the World Health Organization that recently traveled to the country to probe the gush of infections that began in March said the hospital outbreaks appear to be amplifying what may be a seasonal increase in MERS activity.

Frieden said the latest imported case "is unwelcome but not unexpected news." He said health officials expect that other similar cases will be detected, but they emphasized that the infections pose a low public health threat, because MERS-CoV does not appear to spread easily in community settings. The human-to-human cases that have occurred have been among close contacts, such as healthcare workers or family members caring for sick patients.

That no secondary cases have been detected in connection to the Indiana case is encouraging, he said, adding that a team from the CDC is in Saudi Arabia helping with ongoing disease investigations.

Anne Schuchat, MD, director of the CDC's National Center for Immunization and Respiratory Diseases, said CDC scientists with their partners in Greece and Indiana have compared recent sequences from imported MERS patients and found no significant changes and that the CDC has submitted a sample from the Indiana patient to GenBank.

Out of an abundance of caution, health officials from as many as 20 states with help from the CDC will call nearly 500 people who flew with the patient on three legs of the patient's trip: from London to Boston, from Boston to Atlanta, and from Atlanta to Orlando. Though the CDC emphasized that the risk of MERS transmission on an airline flight appears to be low, fellow travelers will be asked to submit a respiratory sample to see if any asymptomatic infections have occurred.

Public Health England (PHE) said it was advised today about a MERS illness in a person flying from Jeddah to the United States through London on May 1. It said the passenger flew Saudi Airlines flight 113 from Jeddah to London, transferring at Heathrow for onward travel to the United States. It said it was the second instance of a MERS case-patient flying through Heathrow to the United States and added that follow-up on passengers on the first flight, from Riyadh to London, found no other cases.

In its statement, PHE said that though he risk it low, it will follow up with any UK passengers who were sitting in the vicinity of the person with MERS.

The CDC did not specify airlines or flight numbers for the US legs of the trip, adding that the follow-up procedure involves contacting passengers directly. Schuchat said the process is labor-intensive and for the first imported case required about 1,000 hours of CDC worker time over the course of a weekend.

At today's briefing, CDC officials said the man's family is in voluntary home quarantine.

Earlier patient discharged from hospital

The patient with the nation's first imported MERS case was discharged from the hospital on May 10, according to a statement from the Indiana State Department of Health (ISDH).

Alan Kumar, MD, chief medical information officer for Community Hospital in Munster, where the man had been hospitalized, said the patient has tested negative for MERS, no longer has symptoms, and no longer poses a threat to the community. He added that the hospital finalized the discharge plan with the CDC and the ISDH.

The ISDH said multiple tests done at different times by the Indiana state lab and the CDC were negative for ongoing MERS infection in the patient and that no other cases have been detected. Hospital staff who had direct contact with the patient are still on temporary home isolation and are being monitored for symptoms. They can return to work after the incubation period passes and lab tests are negative for the virus.

The man had traveled from Riyadh to London on Apr 24, then continued to the United States, where he arrived in Chicago then traveled by bus to Highland, Ind., to visit relatives.

He had some symptoms before he flew, and after having respiratory symptoms he was admitted to the Munster, Ind., hospital on Apr 28 and tested positive for MERS-CoV on May 2.

Saudi Arabia reports 18 new cases, 14 deaths

Meanwhile, over the last 3 days Saudi Arabia's health ministry (MOH) has reported 18 new MERS-CoV infections, three of them fatal, along with 11 more deaths among previously confirmed cases. The latest cases are all from the country's hotspots for the disease, including Riyadh (9), Jeddah (6), Medina (2), and Mecca (1).

The patients are all adults, ranging in age from 29 to 80. Twelve are women and six are men. Nine of them had contact with confirmed cases. The reports don't specify if the cases involved healthcare workers, and no exposures to camels or animal environments were listed for any of the patients.

Two patients are listed as asymptomatic, though the ministry's statement yesterday noted another asymptomatic patient whose infection is not detailed or included in the country's case count. Eight patients are listed in stable condition, five are being treated in intensive care units (ICUs), and three died from their infections.

Illness onsets, available for 14 of the patients, range from Apr 18 through May 11. Hospitalization dates, listed for 12 cases, range from Apr 4 through May 12, though most were hospitalized in May.

Among the new cases, fatalities include an 80-year-old woman from Riyadh who had apparently been hospitalized since Apr 19 for other conditions before she got sick with respiratory symptoms on May 1, a 66-year-old man from Medina who got sick on May 1 and was hospitalized the same day, and a 35-year-old woman from Riyadh who was hospitalized on May 1.

Of the previously confirmed cases that were fatal, patients' ages ranged from 22 to 82, though many of them were people over age 60. Six were men and five were women. Dates of death ranged from May 7 through May 11. Six of the people were from Riyadh, three were from Jeddah, and two were from Medina.

The new infections and deaths lift Saudi Arabia's MERS count to 491 cases and 147 deaths.

Jordan reports fatal case

In Jordan, a man in his 50s died of MERS yesterday, marking the country's fifth death from the infection, according to an Agence France-Presse (AFP) report published today. The story said the man worked in a private hospital. A story from the Chinese news agency Xinhua said the man was a nurse and that his case was the country's ninth.

News editor Robert Roos contributed to this story.

See also:

May 12 FDH statement

May 12 CDC MERS background update

May 12 PHE statement

May 10 ISDH press release

May 10 Saudi MOH statement on 7 cases

May 11 Saudi MOH statement on 3 cases

May 12 Saudi MOH statement on 8 cases

Saudi MOH MERS page with case count

May 12 AFP story on Jordan case

May 12 Xinhua story on Jordan case