Since the first identification of a novel coronavirus in September 2012 , four confirmed cases had been identified in the United Kingdom (UK) by the Health Protection Agency (HPA) by 19 February 2013: two imported cases and two indigenously acquired cases linked to the second imported case.
The first case of novel coronavirus identified in the UK was in a foreign national transferred to London for the treatment of a serious, unexplained respiratory illness in September 2012 . Coronavirus testing was undertaken following the announcement that a new coronavirus had been discovered in a Saudi Arabian national with a similar illness. The patient was very unwell, requiring intensive care and extra corporeal membrane oxygenation (ECMO), and remains very unwell. Extensive follow up of all close contacts (household and healthcare) by the HPA identified a number of persons with mild respiratory illness in the 10 days following exposure but none of these contacts had novel coronavirus infection detected on respiratory sampling or serology .
On 11 February 2013, the HPA published details of an adult UK resident (the index case), with confirmed novel coronavirus infection and influenza A infection, who had travelled to Pakistan and Saudi Arabia in the 10 days before illness onset. This individual had developed respiratory symptoms on 24 January, prior to returning to the UK on 28 January. While staying with family at home in the UK, this individual's condition deteriorated and they were admitted to hospital in Birmingham, before being transferred to Manchester, where they remain in intensive care, with ECMO.
On 6 February, an adult household member of the case who had not recently travelled abroad – but who had been in sustained close contact with the index case from their arrival in the UK until hospital admission – became unwell with a febrile respiratory illness. This third case, on admission to hospital in Birmingham, was confirmed to have novel coronavirus infection. Their condition worsened – requiring intensive care and ECMO – before the patient died on 17 February. This patient had an existing medical condition that may have made them more susceptible to a respiratory infection.
On 5 February, an adult member of the same extended family of the two confirmed cases – who had not travelled abroad – developed an influenza-like illness. The illness remained mild, not requiring hospital admission, and there has been a full recovery. A sputum sample from this case was later confirmed to contain novel coronavirus. This case had limited exposure to the index case on three occasions while the latter was in hospital, and had no contact with the second case.
Infection control measures around the three recent cases have followed UK national guidance  and contact tracing and follow-up is continuing for those persons who may have been in close contact with any of the three cases.
Contacts in three main settings are being followed up:
- Aircraft: the aircraft passengers in the same row and the two rows in front and behind the case on a flight from Saudi Arabia to London when the first case had been unwell;
- Household: the family and friend household contacts of all three cases;
- Health care: the healthcare workers, patients and family and friends who were in contact with the cases in a health care setting.
The routes of transmission to humans of the novel coronavirus have not yet been fully determined, but the recent UK experience provides strong evidence of human-to-human transmission in at least some circumstances. The limited contact that one of the cases had with the index case, however, leaves open the possibility of an intermediary case within the extended family.
The three recent cases in the UK represent an important opportunity to obtain more information about the characteristics of this infection in humans and risk factors for its acquisition, particularly in the light of the first ever recorded instance of apparently lower severity of illness in one of the cases, and the occurrence of dual infection in the index case.
References1. Corman VM, et al. Detection of a novel human coronavirus by real-time reverse-transcription polymerase chain reaction. Euro Surveill. 2012 Sep 27; 17(39). pii: 20285. http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=20285.
2. Bermingham A, et al. Severe respiratory illness caused by a novel coronavirus, in a patient transferred to the United Kingdom from the Middle East, September 2012. Euro Surveill. 2012 Oct 4; 17(40): 20290. http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=20290.
3. Pebody RG, et al. The United Kingdom public health response to an imported laboratory confirmed case of a novel coronavirus in September 2012. Euro Surveill. 2012 Oct 4; 17(40): 20292. http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=20292.
4. Health Protection Agency. Infection Control Advice – Novel coronavirus cases Version 1.3, HPA, 4 October 2012. http://www.hpa.org.uk/webc/HPAwebFile/HPAweb_C/1317136232722.