Saudi Arabia reported another 26 MERS-CoV (Middle East respiratory syndrome coronavirus) cases over the weekend, and Egypt identified its first case, but the latest sequencing findings showed no mutations that might help explain the virus's accelerated spread over the past month.

With five deaths among the new cases and five in previously reported cases, Saudi Arabia's MERS death toll reached 102, while its overall case count jumped to 339. Fifteen of the 26 new cases are in Jeddah, the leading MERS hot spot in the country.

Egyptian case

Egypt's first case involves a 27-year-old Egyptian civil engineer who lives in Riyadh and was diagnosed Apr 26 after returning to Egypt, according to the Associated Press. He was being treated for pneumonia in a Cairo hospital and was in stable condition, Reuters reported.

Egypt becomes the 15th country to report a MERS case and the latest one outside the Arabian Peninsula. Concern about the virus has been rising in Egypt because of recent evidence of the virus in camels there.

In addition, the World Health Organization (WHO) on Apr 26 provided some information about seven MERS cases that were reported by the United Arab Emirates (UAE) via the media on Apr 25. It said all the patients are currently well.

Sequencing results

The sequencing findings were provided by Christian Drosten, MD, a virologist at the University of Bonn, in an Apr 26 post on ProMED, the disease monitoring service of the International Society for Infectious Diseases.

Drosten said his lab sequenced the nearly complete genomes of three MERS-CoV isolates that were collected in Jeddah in early April and were sent to Germany on Apr 14 by the Saudi Ministry of Health (MOH). The samples were from patients in two different hospitals.

"Genome sequences of all 3 viruses are highly similar to each other but not identical, and are highly similar to a large number of known MERS-CoV sequences," Drosten wrote. "There are no genome insertions or deletions suggestive of sudden major changes.

"The receptor-binding domain in the spike protein thought to influence the virus's ability to be transmitted or spread is 100 percent identical to the binding site in a large number of known MERS-CoV genome sequences. Based on genome comparison with other MERS-CoV strains there is no reason to assume that the sequenced viruses from Jeddah have acquired changes increasing their pandemic potential."

In addition, Drosten's team has partially sequenced the spike protein genes from another 25 isolates and found them a 100% match for the other sequenced isolates, he reported. But he cautioned that more sequencing data are needed before any conclusions about transmission patterns can be reached, adding that sequencing of later isolates is under way.

Drosten also took the opportunity to gently suggest that complaints about a slow Saudi response to the outbreak may not be entirely justified.

"In light of some of the recent comments implicating delays in following up on the outbreak it is worth considering the timing and the workload associated with careful testing and internal confirmation done in Jeddah," he wrote. He said the date when Saudi officials sent the samples to Germany was only about a week after the samples were received at a regional lab in Jeddah, where they had to be tested and retested before being sent on to Riyadh.

Also, he explained that when the samples arrived in Germany, it took 3 days to get them through customs, and Easter holidays also delayed the start of sequencing.

Two sets of Saudi cases

Saudi Arabian officials reported 10 MERS cases on Apr 26 and another 16 yesterday. Besides the 15 cases in Jeddah, they included 4 in Riyadh, 1 in Mecca, and 6 in Tabuk, a northwestern city.

Officials said 7 of the patients were asymptomatic, 8 were in stable condition, 6 were in intensive care units, and 5 died.

One of the deaths was in a 9-month-old child who was hospitalized in Riyadh with a kidney condition on Apr 4 and died 3 days later, according to a computer translation of the MOH statement. Other deaths among the new cases involved three women in Jeddah, ages 63, 65, and 61, and a 55-year-old man in Riyadh.

There were 9 healthcare workers among the latest cases, including a pharmacist, 2 doctors, and 6 nurses. Seven of these were in Jeddah, 1 in Mecca, and 1 in Riyadh.

MERS cases in children have been rare, but the new cases included one in a 16-year-old, in addition to that of the 9-month-old who died. The teenager was listed in stable condition.

The 339 cases now recorded by the Saudi MOH are more than double the 163 cases that CIDRAP News files indicate that the country had at the beginning of April. The current death toll of 102 compares with 64 deaths listed at the start of the month.

In other news, Saudi Arabia's new health minister designated three hospitals—one each in Jeddah, Riyadh, and the Eastern region—to serve as special centers for MERS patients, according to a machine-translated media report posted on Avian Flu Diary, an infectious disease blog.

The story, from the newspaper Al Riyadh, listed the hospitals as King Abdullah Medical Center in Jeddah, Prince Mohammed bin Abdul Aziz Hospital in Riyadh, and Dammam Medical Center in the Eastern region.

WHO on UAE cases

The WHO said on Apr 26 that all seven UAE patients who were first reported by the media a day earlier were well, though some had been sick earlier. The patients, all from Abu Dhabi, range from 4 to 45 years old.

One patient, a 45-year-old woman, is the daughter of another MERS patient whose case was reported Apr 22, the agency said.

Five other patients had contact on Apr 10 with a previously confirmed case-patient. Earlier this month (Apr 16 and 17), the WHO reported that a total of 14 other UAE MERS cases were identified through testing of contacts of a patient who died on Apr 10. The latest statement did not specify whether any or all of the seven new cases were linked to that same case.

In addition, two patients, both men in their 30s, own farms, and one of them has had contact with camels, the WHO said. It said all the patients were in isolation in a hospital and that their contacts were being screened.

With the seven cases, the WHO's MERS count increased to 261 cases and 93 deaths (many cases reported by governments and the media have not yet been recognized by the agency).

See also:

Apr 26 Saudi MOH statement on 10 new cases

Christian Drosten's Apr 26 ProMED post on sequencing results

Translated Apr 27 Saudi statement on 16 cases, via Avian Flu Diary

Apr 26 WHO statement on seven UAE cases

Apr 28 AP story on Egyptian case

Apr 28 Reuters story on Egyptian case

Previous 25 CIDRAP News stories discussing possible causes of recent increase in cases: Apr 23 and Apr 25