Apr 4, 2013 (CIDRAP News) – Dutch and German researchers today said they have devised a serology test that can detect novel coronavirus (NCoV), as well as the one that causes SARS, which should help health officials detect and track the spread of the new virus
The scientists wrote in Eurosurveillance that medical teams often need to couple serologic testing with real-time reverse-transcription polymerase chain reaction (RT-PCR) tests, because the latter may be less sensitive during the acute phase of illness when lower respiratory tract samples aren't as available.
Also, they noted that serologic tests are an important tool for monitoring the evolution of an outbreak, determining if there are asymptomatic or mild cases, and finding evidence of exposure to the virus in animals. Experts can use two other lab tests to detect NCoV, but one can yield false-positive results due to co-circulation of other coronaviruses, and the other—virus neutralization—can be difficult to implement and isn't widely available.
In the 17-case NCoV outbreak, 2 patients had mild infections, which raised questions about the spread of the virus, as well as its clinical spectrum.
The new protein microarray–based serology test so far is highly specific for immunoglobulin M (IgM) and IgG antibodies against new coronaviruses, the group reported. They noted, however, that because there are so few positive patient sera, it's difficult to gauge the assay's sensitivity. "For this essential clinical validation, international sharing of positive sera by (national) laboratories in possession of such sera is a prerequisite," they wrote.
Researchers said the assay can also be modified to test animals, which could help identify reservoirs, a step needed to explore the epidemiology of NCoV.
New details about UAE case
In other NCoV developments, new information emerged today about a man from the United Arab Emirates (UAE) who recently died from the disease in a German hospital. The fresh details came from a ScienceInsider interview with a German doctor from the Munich hospital at which the patient was treated.
Clemens Wendtner, MD, professor of medicine and assistant medical director at the University of Cologne, said the patient had flown to Germany several times for multiple myeloma treatment, and returned recently when his condition deteriorated and he was having pulmonary problems.
Doctors at the Munich hospital tested him for coronavirus after they noticed he had been started on oseltamivir but had not improved. The patient's samples tested positive for NCoV at the University of Bonn, Germany's reference lab for the new virus.
Of about 60 contacts, 10 had coughing or flulike symptoms. Testing found that all were negative for NCoV, Wendtner told ScienceInsider.
He said screening tests in the Arabian Peninsula are underdeveloped and there may be a number of undetected cases. Wendtner told the journal that officials from the UAE are interested in setting up testing and that German experts have agreed to help them.
Regarding the patient's exposure to racing camels, Wendtner said the patient got sick after close contact with a sick camel and was in an Abu Dhabi medical unit 3 days later. Another family member also got sick after close contact with the camel, but so far German officials have not been able to follow up with the other man.
The camel is reportedly still alive, and officials hope to acquire some samples to test from the animal, according to the report.
Apr 4 Eurosurveillance report
Apr 4 ScienceInsider report