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Commentary
UK Beta
Coronavirus Cluster Media Myths
Recombinomics
Commentary 13:30
February 19, 2013
"If it was somebody who was not related or a nurse or a doctor - that would be a lot more serious."
The above comments, in response to the lab confirmation of a familial cluster in the UK involving the novel beta coronavirus, signal the start of the silly season for comments on the human to human (H2H) transmission of the virus. The latest cluster is the fourth cluster involving at least one confirmed case, and the third cluster involving two or more confirmed cases. Two of the prior clusters did involve health care workers and one of the clusters included the death of two health care workers who were lab confirmed. Moreover, 9 of the 12 confirmed cases were linked to clusters, as were a dozen probable cases, as well as a dozen suspect cases. Thus, of the three dozen confirmed, probable, or suspect cases, only three were not linked to clusters of symptomatic case.
The most recent cluster involved three family members, but that cluster addressed three important aspects of novel coronavirus infections which had not been lab confirmed previously. The index case (60M) developed symptoms while performing Umrah in Saudi Arabia. When he returned to the UK his condition deteriorated and hye was lab confirmed of being co-infected with the novel coronavirus, as well as pandemic H1N1 (H1N1pdm09), which have never been reported previously.
His son (39M) then became symptomatic and was also lab confirmed for infection by the novel coronavirus. Since the son had no recent travel history outside of the UK, the confirmation signaled the first confirmed export/transmission of the novel virus (from the father infected in Saudi Arabia to the son infected in the UK). The son has now died.
In addition to the infection of the son in the UK, another family member developed symptoms in the UK and was lab confirmed. The absence of travel defined an additional example of human transmission in the UK, and the third case did not require hospitalization or medical attention. Thus, the third family member represented the first confirmation of the novel coronavirus in a mild case.
However, cases with mild symptoms were also observed in the first cluster which also involved transport of the virus to the UK. The index case (49M) was a Qatari who also developed symptoms while performing Umrah in Saudi Arabia in August, 2012. Initial symptoms were mild and resolved three days after his return to Qatar. However, his symptoms re-appeared two weeks later on September 3 and his condition deteriorated over the next 8 days, He was transported to the UK on September 11, but the etiology was unknown. A ProMED publication of a letter from a physician in Jeddah (which is adjacent to Mecca) described a fatal case (60M) with SARS-like symptoms which matched the Qatari case. Initial testing had been negative for SARS and other coronaviruses, but testing using a universal set of PCR primers identified a novel group 2c coronavirus, which had never been reported in humans. A sample from the Qatari case was then tested with the same universal primer set and was positive. The sequence of the 206 BP insert matched at 205 position (<99.5% identity) confirming that both patients had been infected with the same novel coronavirus.
This confirmation raised considerable concern in the UK hospital, since the Saudi patient had died and the Qatari case was in critical condition. Moreover, and the initial impact of the SARS CoV on health care workers was well known. Therefore, health care workers with contact with the confirmed case wore personal protective equipment and family and healthcare workers with contact with the patient in the UK were identified. 64 healthcare workers were identified, and 13 were symptomatic. However, all cases had mild symptoms and recovered without hospitalization. Samples from 10 of the cases were tested with the universal primer set and were negative. All recovered and additional infections were not found.
However, the detection of a novel coronavirus in the two confirmed cases raised concerns for a serious cluster involving health care workers in Jordan in April. The ECDC described the cluster of 11 symptomatic cases linked directly or indirectly to an ICU. Seven were nurses and an additional case was a doctor. The ECDC summary was based on a Jordan Ministry of Health report issued on April 19, the date of death for one of the nurses (45F). Media reports noted that the cases had a wide range of symptoms. One was not hospitalized, while several were briefly hospitalized. Others, however, had severe pneumonia similar to SARS cases. Moreover, an intern (25M) died a week after the death of the nurse. Jordan sent samples to labs in France and Egypt, but testing for known respiratory viruses, including SARS CoV were negative.
However, samples were sent to Egypt for retesting by NAMRU-3 using probes targeting the novel coronavirus. The two fatal cases were confirmed. Details on the failure to detect the virus in the surviving symptomatic cases were not released, but WHO classified these cases as probable, based on symptoms and an epidemiological study.
There were similar detection issues with a familial cluster in Saudi Arabia. Four family members were symptomatic and two died. However initial testing only confirmed the virus in two cases, one fatal (39M) and one who recovered (31M). The father (70M) of the fatal case died 4 days prior to his son, and was subsequently confirmed. However, the fourth family member tested negative and was classified as a probable case. The disease onset date for the confirmed surviving case was 6-8 days after the fatal case of the son, strongly supporting H2H transmission.
Now that a member of the third cluster has died, media reports will focus on his weakened condition or put the case fatality rate at 50%, although the probable cases (all of whom survived) would lower the CFR to 25% and addition of the suspect cases would lower the CFR to 16.7%.
However, the fact that only three of the confirmed cases were not linked to symptomatic cases, and only four of the confirmed cases were not linked to fatal confirmed cases, signals the ability of this novel coronavirus to easily transmit in humans, silly comments that heavily rely on biased surveillance using a suspect assay, notwithstanding.
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