COVID-19: investigation and initial clinical management of possible cases

Updated 25 March 2022

This guidance was withdrawn on

Information for the management of COVID-19 cases can be found at NICE guideline [NG191] – COVID-19 rapid guideline: managing COVID-19.

1. Conducting a clinical assessment

There is general public health advice available for people with symptoms of COVID-19.

Some patients may present to clinicians for assessment. When conducting these assessments clinicians should:

2. COVID-19 symptoms and testing

The 2 main types of test currently being used for COVID-19 testing are polymerase chain reaction (PCR) and lateral flow device (LFD) antigen tests.

Individuals with the following main symptoms of COVID-19 who are well enough to remain in the community should follow the people with COVID-19 and their contacts and arrange to have a PCR test:

  • new continuous cough


  • temperature ≥37.8°C


  • loss of, or change in, normal sense of smell (anosmia) or taste (ageusia)

A wide variety of other clinical symptoms have been associated with COVID-19. Clinical and public health professionals who wish to confirm or exclude COVID-19 can access community testing even if the patient does not have any of the main symptoms.

Some patients may have tested positive on an LFD test. Currently, at high prevalence a follow-up PCR test is not required as a positive LFD result is likely to indicate a true infection. Clinicians and public health professionals can still advise a PCR test for these patients; reasons for doing so include (but are not limited to) eligibility for certain COVID-19 treatments, recruitment to a clinical trial or for monitoring new and emerging variants.

Patients with acute respiratory infection, influenza-like illness, clinical or radiological evidence of pneumonia, acute worsening of underlying respiratory illness, or fever without another cause should also have a SARS-CoV-2 PCR test, whether presenting in primary or secondary care. If the clinical suspicion of a false negative test result is high, the patient should be re-tested.

In addition, the following situations should prompt clinicians to consider SARS-CoV-2 PCR testing:

  • onset of delirium (acute confusion) in older people, or in those with dementia or cognitive impairment. Due to communication difficulties these patients may be unable to report symptoms. New infections in people with dementia may manifest as delirium
  • when investigating a possible infection in the immunocompromised in whom atypical COVID-19 presentations may occur

3. Actions to take if a possible COVID-19 case requires admission to hospital

3.1 Isolation

Ensure the patient is placed in respiratory isolation or within a specified cohort bay and the PPE described in the IPC guidance is worn by any person entering the room. Ensure that the patient, potentially contaminated areas, and waste are managed as per the IPC guidance.

3.2 Sampling and testing

Testing of patients in hospital can be arranged via the hospital laboratories or via point of care tests if applicable.

Testing for respiratory viruses other than SARS-CoV-2 can be guided by the current epidemiology as noted in the national flu and COVID-19 surveillance reports.

For hospitalised patients with an acute respiratory infection, the current level of influenza or respiratory syncytial virus (RSV) activity should guide the need to screen for influenza and RSV at the same time as SARS-CoV-2 testing.

Alternative diagnoses of respiratory infections including influenza and other respiratory viruses, as well as other causes of respiratory illness should be considered if the SARS-CoV-2 test is negative.

3.3 Reporting to your local health protection team

The local health protection team (HPT) should be informed about COVID-19 outbreaks and clusters in high-risk settings, including:

  • long-term care facilities and other institutional residential settings
  • prisons or prescribed places of detention
  • hospitals and healthcare settings

3.4 COVID-19 therapeutics

There are a variety of treatments available for COVID-19. This section provides a brief overview. Refer to the NICE guidance for treatment of COVID-19 for more detailed information.

Currently available treatments include antiviral drugs, immunosuppressive agents and monoclonal antibodies. The indication for use of these agents depends on the timing of prescribing in the course of the illness, among other factors.

3.4.1 Antivirals

The oral antivirals molnupiravir and paxlovid are currently provided in the community to immunocompromised patients with confirmed infection or to those eligible via the PANORAMIC trial. For a select group of hospitalised patients, the intravenous antiviral agent remdesivir is available.

3.4.2 Immunosuppressive agents

These agents dampen the overactive immune response that severely ill patients with COVID-19 often display. Dexamethasone has been shown to decrease mortality significantly in those receiving respiratory ventilation, as well as those receiving oxygen. The anti-IL-6 agents tocilizumab and sarilumab can be given to patients with a measurable inflammatory response and oxygen demand; these agents also significantly decrease mortality as well as the risk of progression to invasive ventilation.

3.4.3 Neutralising monoclonal antibodies (nMabs)

Monoclonal antibodies have similarly shown to decrease mortality in COVID-19 patients, most starkly in those without SARS-CoV-2 antibodies. nMabs can also be given as post-exposure prophylaxis within a few days after exposure to a confirmed case of COVID-19. The efficacies of these treatments can depend on various factors, including the circulating variant and the time between exposure or start of symptoms and the start of the treatment.

3.4.4 Antithrombotic agents

For treatment and prevention of COVID-19 related thromboembolic processes, refer to the NICE guidance for managing COVID-19.

3.4.5 Other treatments

There are various other treatments still under investigation. Many other agents have been studied without convincing evidence of effectiveness.

3.5 Discharge of patients

If the patient is clinically well and suitable for discharge from hospital, they can be discharged to the appropriate destination following the guidance on stepdown of infection control precautions and discharging COVID-19 patients and in the DHSC hospital discharge guidance. It is best practice to provide written instructions on any ongoing isolation recommendations.

4. De-escalation of infection prevention and control (IPC) measures in hospital

Decisions about de-escalation of IPC measures on admitted patients who will remain in hospital should be made in discussion with local infection prevention and control specialists. Further guidance is available on stepdown of infection control precautions and discharging patients.

5. Associated legislation

Please note that this guidance is of a general nature and that an employer should consider the specific conditions of each individual place of work and comply with all applicable legislation, including the Health and Safety at Work etc. Act 1974.

Cases of COVID-19 and of SARS-CoV-2 infection are statutorily notifiable. When a registered medical practitioner has reasonable grounds for suspecting a patient they are attending has COVID-19, such cases should be notified. Test-confirmed SARS-CoV-2 infections should be notified by the relevant laboratory. Guidance is available on reporting notifiable diseases. It is important to ensure suspected and confirmed cases of COVID-19 are correctly recorded in the patient’s records – see NHS Digital’s website for SNOMED codes.