Pneumonia, COVID-19 and preparing for winter 2021-22

Written by: Rosie Lobley and Ben Caldwell

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12 November was World Pneumonia Day, raising awareness and advocating action to combat the threat of pneumonia around the world.1 Pneumonia is a lung infection which causes the tissues of one or both lungs to become inflamed, while the alveoli may fill with fluid. Common symptoms include a dry or productive cough, chest pain, shortness of breath, a rapid heartbeat and influenza-like symptoms such as a high temperature, appetite loss, sweating and shivering.2 In 2019, pneumonia killed around 2.5 million people worldwide.1

covid-19 pneumonia winter 2021

COVID-19 and seasonal illness

Pneumonia can occur as a complication of COVID-19. Pneumonia associated with COVID-19 lasts longer than other forms of pneumonia,13 is more likely to take hold in both lungs and can result in lasting lung damage.14 Ventilated patients with COVID-19 are at heightened risk of contracting VAP compared to patients who are put on ventilation with other conditions.15

If concrete measures had already been in place to prevent and control pneumonia, it is possible that the COVID-19 pandemic could have been addressed more promptly and effectively. Similarly, the measures which have now been adopted to combat COVID-19 could form the basis of a functional post-pandemic pneumonia control strategy.12 Much like influenza and the common cold, COVID-19 appears to be a seasonal virus, with infection rates rising during the cooler winter months.16 Modelling indicates a “substantial wave of COVID-19 infections, hospitalisations and deaths” is likely to occur in winter 2021.17 Meanwhile, as winter approaches, and with many countries lifting infection prevention measures, there is a significant risk of a sharp ‘rebound’ in seasonal influenza  infections.18

Modelling indicates a “substantial wave of COVID-19 infections, hospitalisations and deaths” is likely to occur in winter 2021

Hospital admissions and deaths from influenza and respiratory syncytial virus in winter 2021 may reach double the figures seen in a ‘normal’, pre-COVID year.19 Researchers in the US have expressed concerns about the potential of a COVID–influenza ‘twindemic’,20 particularly given that patients who become coinfected with COVID-19 and influenza simultaneously are twice as likely to die as those with COVID-19 alone.21

Deaths from COVID-19 and influenza

Preparedness and resilience

With the above challenges in mind, preparing health services for increased strains over winter is at the forefront of the healthcare agenda. The UK’s Academy of Medical Sciences has produced a comprehensive report on winter preparedness for 2021/22, advocating: continued prioritisation of vaccination and boosters; improved capacity for people with suspected COVID-19 to test and self-isolate; continued use of masks and working from home where needed; and increased support for the healthcare workforce.22 Similarly, the World Health Organization has called for increased efforts to provide vaccines and support to healthcare workers, particularly in low- and middle-income countries.23

Vaccination is widely acknowledged to be an essential step in the route out of the COVID-19 pandemic.24 In October 2021, the UK government launched its largest ever winter vaccine drive to ensure as many residents as possible receive influenza vaccines and ‘booster’ doses of the COVID-19 vaccine.25 As of November, booster doses – which enhance the immunity provided by COVID-19 vaccines as it diminishes over time26 – are now being made available at walk-in clinics in England,27 while Scotland has brought in army personnel to assist with vaccine distribution.28
Rates of COVID-19 vaccination in the UK have continued to increase, with the Office of National Statistics reporting 87.2% of adults aged 16 or over have received both doses of the vaccine.29 The below chart shows modelled percentages of adults who have tested positive for COVID-19 antibodies and received one or two vaccine doses in each UK country.

The human factor

The NHS Confederation, the membership organisation representing NHS services across the UK, has recommended prompt adoption of additional infection prevention measures going into winter to offset the risk of another wave of COVID-19 putting untenable pressure on hospitals and clinical facilities.30 By October, hospital workers were already reporting ‘unsustainable’ levels of pressure.31

With existing staffing issues being further exacerbated by COVID-19-related pressures,32 the possibility remains that the UK could adopt ‘Plan B’ measures: a return to mandatory face masks in some settings, advice to work from home where possible and the introduction of vaccine passports.33 World Pneumonia Day has presented an opportunity to highlight that pneumonia is an ever-present and notably destructive illness. But the risks posed by even innocuous-seeming conditions like influenza are expected to increase dramatically during winter 2021, so winter preparedness is a significant and immediate point of concern.

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