Background and summary of novel coronavirus infection – as of 30 November 2012
Over the past two months, WHO has received reports of nine cases of human infection with a novel coronavirus. Coronaviruses are a large family of viruses; different members of this family cause illness in humans and animals. In humans, these illnesses range from the common cold to infection with Severe Acute Respiratory Syndrome (SARS) coronavirus (SARS CoV).
Thus far, the cases reported have come from Qatar, Saudi Arabia and Jordan. All patients were severely ill, and five have died.
The two Qatari patients are not linked. Both had severe pneumonia and acute renal failure. Both are now recovering.
A total of five confirmed cases have been reported from Saudi Arabia. The first two are not linked to each other; one of these has died. Three other confirmed cases are epidemiologically linked and occurred in one family living within the same household; two of these have died. One additional family member in this household also became ill, with symptoms similar to those of the confirmed cases. This person has recovered and tested negative, by polymerase chain reaction (PCR) tests, for the virus.
Two confirmed cases have been reported in Jordan. Both of these patients have died. These cases were discovered through testing of stored samples from a cluster of pneumonia cases that occurred in April 2012.
The two clusters (Saudi Arabia, Jordan) raise the possibility of limited human-to-human transmission or, alternatively, exposure to a common source. Ongoing investigation may or may not be able to distinguish between these possibilities.
The current understanding of this novel virus is that it can cause a severe, acute respiratory infection presenting as pneumonia. Acute renal failure has also occurred in five cases.
WHO recognizes that the emergence of a new coronavirus capable of causing severe disease raises concerns because of experience with SARS. Although this novel coronavirus is distantly related to the SARS CoV, they are different. Based on current information, it does not appear to transmit easily between people, unlike the SARS virus.
WHO has closely monitored the situation since detection of the first case and has been working with partners to ensure a high degree of preparedness should the new virus be found to be sufficiently transmissible to cause community outbreaks. Some viruses are able to cause limited human-to-human transmission under condition of close contact, as occurs in families, but are not transmissible enough to cause larger community outbreaks. Actions taken by WHO in coordination with national authorities and technical partners include the following:
- Investigations are ongoing to determine the likely source of infection and the route of exposure. Close contacts of confirmed cases are being identified and followed up.
- An interim surveillance recommendation has been updated to assist clinicians to determine which patients should undergo laboratory testing for the presence of novel coronavirus.
- Laboratory assays for the virus have been developed. Reagents and other materials for testing are available, as are protocols, algorithms and reference laboratory services. WHO has activated its laboratory network to assist in testing and other services. WHO has also issued preliminary guidance for laboratory biorisk management.
- Guidance is available for infection control.
Based on the current situation and available information:
- WHO encourages all Member States to continue their surveillance for severe acute respiratory infections (SARI) and to carefully review any unusual patterns.
- Further, testing for the new coronavirus of patients with unexplained pneumonias should be considered, especially in persons residing in or returning from the Arabian peninsula and neighboring countries. Any new cases should be promptly reported both to national health authorities and to WHO.
- In addition, any clusters of SARI or SARI in health care workers should be thoroughly investigated, regardless of where in the world they occur. These investigations will help determine whether the virus is distributed more widely in the human population beyond the three countries that have identified cases.
- WHO does not advise special screening at points of entry with regard to this event nor does it recommend that any travel or trade restrictions be applied.
WHO continues to work with Member States and international health partners to gain a better understanding of the novel coronavirus and the disease in humans and will continue to provide updated information. As the situation evolves, WHO will reassess its guidance and revise it accordingly.