Published Date: 2012-12-23 15:21:17
Subject: PRO/AH/EDR> Novel coronavirus - Eastern Mediterranean (05): WHO, transmission route
Archive Number: 20121223.1465597
NOVEL CORONAVIRUS - EASTERN MEDITERRANEAN (05): WHO, TRANSMISSION ROUTE, JORDAN
A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases
Date: 21 Dec 2012
Source: GAR [edited]
Background and summary of novel coronavirus infection -- as of [21 Dec 2012]
Over the past 3 months, WHO has received reports of 9 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).
This summary provides the latest information on all reported cases and provides details of a WHO mission to Jordan, which has concluded since the last web update.
Thus far, the laboratory confirmed cases have been reported by Qatar (2 cases), Saudi Arabia (5 cases), and Jordan (2 cases). All patients were severely ill, and 5 have died.
A total of 5 confirmed cases have been reported from Saudi Arabia. The 1st 2 are not linked to each other and lived in different parts of the country; one of these has died. Three other confirmed cases are epidemiologically linked and occurred in one family living within the same household; 2 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 in health care workers that occurred in April 2012.
In November 2012, staff from WHO Headquarters and the Eastern Mediterranean Regional Office were invited to Jordan to assess severe acute respiratory infection (SARI) surveillance and infection prevention and control measures, and to review the April 2012 outbreak. The mission included hospital site visits, interviews with patients, relatives and caregivers, and review of case files. In addition to the 2 previously confirmed cases, a number of health care workers with pneumonia associated with the cases were also included in the review and are now considered probable cases.
The main findings of this mission are:
- The index case among this cluster could not be determined.
- All patients had significant respiratory disease presenting as pneumonia. Disease was generally milder in the unconfirmed probable cases. One patient who is a probable case had symptoms that were mild enough to be managed at home and was not admitted to hospital.
- No patient in this cluster had renal failure.
- One patient presented with pneumonia and was discovered to also have pericarditis. This patient had laboratory confirmation of infection and has died.
- A 2nd patient developed disseminated intravascular coagulation as a complication of severe respiratory disease. This patient also had laboratory confirmation of infection and has died.
- The method of exposure is uncertain.
- There was no history of travel or contact with animals among confirmed or probable cases.
- Most family members and health care workers who were closely exposed to confirmed and probable cases did not develop respiratory disease. However, the appearance of pneumonia in some who provided care and in at least 2 family members with direct personal contact increases the suspicion that person-to-person transmission may have occurred. The possibility of exposure to a common source has not been definitively excluded. Further investigation with serological testing (when it becomes available) to confirm additional cases may help determine the types of exposures that result in infection.
The current understanding of this novel virus is that it can cause a severe, acute respiratory infection presenting as pneumonia. The additional unconfirmed probable cases in Jordan indicate that milder presentations may also be a part of the clinical appearance associated with infection. Acute renal failure has occurred in 5 of the 9 confirmed cases but was not a prominent feature of the Jordanian cluster. In addition, pericarditis and disseminated intravascular coagulation have now been seen in 2 confirmed 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 or sustainably between people, unlike the SARS virus.
WHO has closely monitored the situation since detection of the 1st 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 conditions 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 now issued preliminary guidance for laboratory biorisk management.
The 3 affected countries either have already acquired or are in the process of acquiring the capacity to test for the novel coronavirus in national laboratories and have enhanced their surveillance activities according to WHO guidance along with other countries in the area.
WHO has created a webpage for coronavirus infections, with guidance for surveillance, infection control, biorisk management, and laboratory testing, which can be found at http://www.who.int/csr/disease/coronavirus_infections/en/index.html.
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. Furthermore, 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.
- When collecting specimens for testing, priority should be given to collection of lower respiratory tract specimens such as sputum and endotracheal aspirates (for intubated patients).
- 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 3 countries that have identified cases.
- Health care workers should be advised to scrupulously adhere to standard infection control precautions for all patients. Droplet precautions should be added to standard precautions for any patient known or suspected to have an acute respiratory infection, including patients with suspected or confirmed infection with novel coronavirus. Airborne precautions should be used for aerosol-generating procedures, including intubation and related interventions. Details can be found on the website listed above.
- 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 monitor this situation closely. Unless information is received that changes our understanding of this virus and the disease it causes, the next web update is expected to be posted during the 2nd week of January 2013.
[The above report provides additional information on a retrospective investigation of the outbreak in Jordan during April 2012. As a reminder, this outbreak (Jordan) remained as an unknown etiology outbreak of severe acute respiratory illness (SARI) until after the novel coronavirus (nCoV) had been identified in the initial 2 reported cases: the report in September 2012 of the 1st identified case in a Saudi Arabian citizen (illness having occurred in June 2012), followed by the report of a 2nd case in a Qatari citizen hospitalized in the UK. Retrospective testing of saved specimens from the cluster of cases in Jordan confirmed the etiology of the outbreak to have been the nCoV involved in Saudi Arabia and Qatar.
While the above report does not mention the number of cases involved in the Jordanian cluster, a report from the European Centre for Disease Control (ECDC) on 3 May 2012 mentioned that there had been 11 cases including 2 deaths.
Points of interest include the absence of identification of the "index case" in the above outbreak. The outbreak involved individuals associated with an intensive care unit (ICU), and it seemed logical to suspect that the index case in this cluster was a patient admitted with a SARI who then infected individuals working in the ICU. Another point of interest is the discussion on the need for development of serologic tests that will permit a better look at the baseline prevalence of prior infections in the community, especially those cases of respiratory illness in contacts of confirmed cases that have tested negative for nCoV infection with the current PCR test available.
If one looks at the epidemic curve of the SARS outbreak, one sees there were one or 2 cases identified sporadically, separated by several weeks, beginning with the presumed index case with date of onset on 22 Nov 2002. It was not until mid to late December 2002 that there were apparent small clusters followed by apparent continual transmission occurring in January 2003. (see Probable cases of SARS by week of onset, Worldwide (5910) 1 Nov 2002 - 10 Jul 2003 http://www.who.int/csr/sars/epicurve/epiindex/en/index1.html. One can't help but wonder on the one hand whether there had been other isolated cases occurring during the period prior to 22 Nov 2002 that were "missed" during the investigations. On the other hand, one wonders whether we might be seeing a similar beginning pattern with this nCoV: isolated/sporadic cases and small clusters with probable person-to-person transmission as a prelude to the virus transitioning into more efficient person-to-person transmission. One hopes that, with the experience of SARS in the not-too-distant past and the lessons learned from that experience, the use of respiratory precautions in the healthcare setting will prevent the development of efficient continued transmission of this nCoV.
For the HealthMap/ProMED map of the Eastern Mediterranean region where the 9 confirmed cases have occurred (Saudi Arabia, Qatar, Jordan), see http://healthmap.org/r/1HAJ. - Mod.MPP]