November 18, 2013
Excerpt:
Another likely case in Spain
Meanwhile, Spanish officials said a woman who traveled to Saudi Arabia with Spain's first probable MERS case-patient is believed to have the virus, the Canadian Press reported today. Officials said the two women shared sleeping quarters.
Spain's health ministry said there was not enough evidence to determine if one of the women caught the disease from the other or if both caught it from a common source, the story said.
The ministry said both women have recovered and have been released from hospitals. Also, authorities said that so far the two women's contacts, including airline passengers and contacts in Spain, have all tested negative for the virus.
Both women tested positive for the virus, but their cases are classified as probable because the WHO case definition requires additional testing, according to the story.
Hartl commented via Twitter today that the first case in Spain, reported by Spanish authorities on Nov 6, still "has not been confirmed to WHO standards." Spanish officials said the case involved a 61-year-old woman.
OIE cool on camel connection
In other developments, the World Organization for Animal Health (OIE) said on Nov 15 that there was still no convincing evidence that camels are a source of MERS-CoV infections in humans, despite recent findings pointing in that direction.
"Currently there is no strong evidence to consider that camels are a source of infection for human cases of MERS," the OIE said in an update of its questions and answers about the virus.
In serologic studies reported in recent months, camels in Egypt, Oman, and the Canary Islands were found to have antibodies to MERS-CoV or a closely related virus. Further, last week Saudi health officials reported finding the virus in a sick camel that belongs to a 43-year-old case-patient from Jeddah.
Saudi officials said the camel tested positive for the virus by polymerase chain reaction. They said they were sequencing the genomes of the camel and patients isolates to see if they match; the results have not yet been reported.
The OIE statement focused on the serologic findings and did not refer to the report of the infected camel.
"Currently there is no strong evidence to consider that camels are a source of infection for human cases of MERS," the statement said. "Based on available epidemiological data it is difficult to explain the relationship between positive serological results in camels and cases of human infections with MERS CoV.
"Indeed, to date, there is no potential similarity between the strain of MERS CoV isolated in humans and the suspicions shown in camels. It is important to remain open minded about all potential sources of exposure for human cases until more information is available."
The agency went on to say that, thanks to cross-reactivity, serologic tests may not distinguish between antibodies to different viruses that have genetic or antigenic similarities.
"Serology tests for MERS CoV have not yet been validated in animals and may not be reliable," the OIE added. "If these tests, which may not be sufficiently specific, are used in animals there is a risk that 'false positive' results will occur because it may not be possible to differentiate antibodies to MERS CoV from antibodies to other coronaviruses, commonly found in animals."
"This is why tests in animal should focus on isolating and identifying the virus itself," the agency said.
The OIE voiced a similar view back in July in an earlier version of the question-and-answer statement. At that point there were no reports of serologic or virologic findings pointing to camels as a source of the virus, but at least one MERS patient had been reported to have had contact with a sick camel before he got sick.
http://www.cidrap.umn.edu/news-perspective/2013/11/who-confirms-kuwaits-mers-cases-spain-cites-new-case
No comments:
Post a Comment