WHO: Revised NCoV Surveillance Recommendations

 

Credit WHO

 

# 7012

 

Last week we learned that the index case in the UK family cluster of novel coronavirus infection – returned from the Middle East last month – was co-infected with influenza A (see Eurosurveillance: H2H Transmission of NCoV In UK Family Cluster), and that two family members were co-infected with Type 2 parainfluenza virus.

 

His positive influenza A test led to a week’s delay in diagnosing the patient’s underlying NCoV infection. 

 

As you might expect – with only 15 confirmed infections worldwide – there is still much unknown about this emerging virus, and the World Health Organization  must continually update and adjust their surveillance recommendations as new data is received.

 

Yesterday, WHO released updated interim guidance on surveillance, parts of which are excerpted below:

Interim surveillance recommendations for human infection with novel coronavirus

As of 18 March 2013

Update

This document provides updated surveillance guidance for novel coronavirus (nCoV). WHO will continue to update these recommendations as more information becomes available.

Current numbers and descriptions of reported cases are found on the main WHO novel coronavirus page.

The primary changes included in this revision are:

• Addition of a recommendation to test individuals with unusually severe respiratory disease even in the presence of another aetiology if the other agent does not fully explain the patient’s illness.
• Specific revised recommendations for countries where the novel coronavirus has been detected.
• Recommendations for investigations and studies to be carried out where cases are detected, which may help describe critical clinical and epidemiological features of the virus.

Background

A number of unanswered questions remain, including the virus reservoir, the means by which seemingly sporadic infections are being acquired, the mode of transmission between infected persons, the clinical spectrum of infection and the incubation period.

In 2013 a third cluster of cases now provides clear evidence of limited, non-sustained human-to-human transmission {HPA LINK }. The mode of transmission has not been determined. One of the cases in the cluster originally tested positive for influenza A and was not initially thought to have infection with nCoV.

One laboratory-confirmed case and one probable case have presented with relatively mild illness with an uneventful recovery; however, most patients have had severe pneumonia. To date, there have been 15 laboratory-confirmed cases of nCoV infection, of which nine have died.

Complications of their clinical course have included severe pneumonia and acute respiratory distress syndrome requiring mechanical ventilation, multi-organ failure, renal failure requiring dialysis, consumptive coagulopathy and pericarditis. At least two cases had a history of recent travel, which occurred five to ten days before onset of illness.

Currently the virus has been found in a limited number of countries, mainly in the WHO Eastern Mediterranean Region.1 However, given the non-specific clinical presentation of the infection the presence of the virus in other areas cannot be ruled out in the absence of laboratory testing.

Objectives of surveillance

The primary objectives of the enhancements described in this document are to:

1 See: http://www.emro.who.int/landing-pages/countries/countries.html

1. Detect early, sustained human-to-human transmission.
2. Determine the geographic risk area for infection with the virus.

Additional clinical and epidemiological investigations (see table below) are needed to:

1. Determine key clinical characteristics of the infection, such as incubation period, the spectrum and natural history of the disease.
2. Determine key epidemiological characteristics of the virus, such as exposures that result in infection, risk factors, reservoir of the virus, secondary attack rates, and modes of transmission.

The following persons should be evaluated epidemiologically and tested for novel coronavirus:

1. A person with an acute respiratory infection, which may include history of fever and cough and indications of pulmonary parenchymal disease (e.g. pneumonia or the acute respiratory distress syndrome [ARDS]), based on clinical or radiological evidence of consolidation, who requires admission to hospital.
   AND any of the following:

• The disease occurs as part of a cluster that occurs within a 10-day period , without regard to place of residence or history of travel, unless another aetiology has been identified.
• The disease occurs in a health care worker who has been working in an environment where patients with severe acute respiratory infections are being cared for, particularly patients requiring intensive care, without regard to place of residence or history of travel, unless another aetiology has been identified.
• Develops an unexpectedly severe clinical course despite appropriate treatment, without regard to place of residence or history of travel, even if another aetiology has been identified, if that alternate aetiology does not fully explain the presentation or clinical course of the patient.

    2. A person with an acute respiratory illness of any degree of severity who, within 10 days  before onset of illness, had close contact with a confirmed or probable case of novel coronavirus infection, while the case was ill.

   3. For countries where the novel coronavirus has already been detected, the minimum standard for surveillance should be testing of patients with severe respiratory disease requiring mechanical ventilation. The minimum standard should include all those in three categories listed above—patients with unexplained pneumonia or ARDS occurring in clusters; health care workers requiring admission for respiratory disease and patients with unusual presentation or clinical course. However, countries where the novel coronavirus has already been detected are also strongly encouraged to consider adding testing for nCoV to current testing algorithms as part of routine sentinel respiratory disease surveillance and, if local capacity can support it, some testing of patients with milder, unexplained, community-acquired pneumonia requiring admission to hospital.

   4.  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.

 

Reporting

Health care providers should report all cases meeting the confirmed or probable case definition immediately, to national authorities, through established reporting channels

 

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