Covid Situation Report: Jun 6, 2024
Update on Covid providing information on positivity and hospital admissions for England and its regions. This post is best viewed using the browser or Substack app.
Introduction
This weekly Covid Situation report was originally posted on my substack ‘Seeing the Forest for the Trees’ where I publish articles on Covid and other topics. You can access my substack at the following link.
A reminder that not all of the data previously included in the situation update is now available on a weekly basis. Where relevant, changes to the content and data sources have been noted.
This week’s report has more data available with the return of the UKHSA surveillance report, which is now only published every two weeks. In addition, the report covers a recent report released by UKHSA on the risk of hospitalization and death due to Covid infection. Finally, a short update on the Spring 2024 booster campaign is provided.
Summary.
The UKHSA surveillance report is now published only every two weeks and less data is provided. In particular, hospital admissions for Covid by region and age are no longer available.
Overall the picture this week is mixed with Covid positivity increasing but hospital admissions remaining stable.
In the past week, the positivity rates for Covid increased from 6.1% to 8% and were highest in those aged 65 years and older.
However, hospital admissions did not increase and remained at relatively low levels.
A report by the UKHSA indicated that, during the recent Winter wave, the likelihood of hospitalisation and death due to Covid infection rose markedly with age. Infected individuals aged 75 and older had an estimated 1 in 30 chance of being hospitalised and an estimated 1 in 138 chance of dying.
The Spring 2024 booster campaign in England closes at the end of June. So far, which just under 3.8 million doses have been administered in the first seven weeks. However, the number of doses given again fell this week. Vaccination coverage for the immunosuppressed continues to remain low.
As always, it’s important to remember that the risk of hospitalisation from Covid infection increases significantly with age and for those immunocompromised. Also Long Covid remains a risk for all as shown by the recent ONS report. Therefore, it is prudent to take appropriate measures such as self-isolating when experiencing Covid symptoms and enhancing ventilation or wearing masks whenever possible.
For those who are interested, I recently published an article covering the ONS data on Long Covid which can be found here. Also a comprehensive review of the evidence in support of wearing masks is available here.
Status of main respiratory diseases in England
This section presents the latest available data on positivity rates for primary respiratory infections in England. It is important to understand that positivity differs from prevalence, which refers to the overall percentage of COVID-19 in the general population. Appendix 1 provides a more detailed explanation of the difference and why positivity rates are a useful indicator of trends in Covid infection levels
The chart below displays the test positivity rates for the main respiratory illnesses in England, including Flu, Covid, RSV, and Rhinovirus.
The Covid positivity rate increased to 8.0% for the week ending Jun 2 indicating that the recent Covid wave is not yet over. Meanwhile, the flu positivity rate has continued to fall and remains significantly lower than that of Covid. Additionally, RSV rates have dropped to very low levels, accompanied by a minor decrease in Rhinovirus rates.
The following chart shoes the positivity rate by age for England. Each panel represents one age group and the title and lines are colour coded. The grey lines show all of the other age groups to provide context. Hover your cursor over one of the chart lines to display the admission rates for all regions.
In the past week, case positivity has increased for all age groups and is highest for individuals 65 years and older.
The final chart in this section shows weekly hospital admissions per 100,000 people in England for the main respiratory diseases.
For the week ending Jun 2, weekly hospital admission rates for Covid remained unchanged and at relatively low levels. Note that hospital admission data for Flu and RSV is no longer published.
It's important to note that while testing policies have been updated from April 1, 2024, the guidelines for testing patients showing Covid symptoms or when a positive result would change the patient's treatment remained unchanged. Consequently, the number of Covid hospital admissions should be a dependable indicator of the virus's prevalence in the community for the period shown in these charts.
Covid hospital admissions and bed occupancy
This section gives a more detailed examination of the most recent daily Covid data for hospitals in England.
NHS England stopped the weekly publication of data used to create these dashboards from April 4, 2024 and have moved to a monthly publication schedule. The next update will be on June 13, 2024 covering May Covid hospital admissions and bed occupancy.
Covid infection hospitalisation and fatality risk
On May 30, UKHSA published a report estimating the hospitalisation and fatality risk from a Covid infection. The analysis was based on data from the ONS Winter Infection Study so covers the period 14 Nov 2023 to 3 Mar 2024.
The Infection Hospitalisation Risk (IHR) measures the risk of hospital admission given that an individual has been infected with the Covid. It is important to note that the IHR represents an average risk for the average person in a subgroup at a population level, individual risk will vary due to co-morbidities and other factors.
The following chart shows the Infection Hospitalisation Risk by age for England based on linking data from the Winter Infection Survey and NHS England records of hospital admissions.
It is very clear that the risk of hospitalisation for infected individuals increases significantly with age. Individuals aged 75 and older face a 1 in 30 probability of hospital admission upon infection, while those between 6 to 17 years old have only a 1 in 3,930 chance.
Before looking at the Infection Fatality Risk it is important to understand how UKHSA defined a Covid death. The study defined a Covid death as those individuals who had Covid listed as a cause of death on their death certificate or individuals that died within 43 days of a positive test. The threshold of 43 days was based of the time delay from a positive test to the date of death for those individuals with Covid on their death certificate.
The following chart shows the Infection Fatality Risk (IFR) by age for England based on linking data from the Winter Infection Survey and deaths.
The gradient of infection risk for fatalities is significantly steeper than for hospitalisations, highlighting the increased risk of death for the elderly from a Covid infection. Indeed, the Infection Fatality Rates for individuals under 45 years old are so low that they do not show up on the above chart. However, those 75 years and older have an estimated 1 in 138 (IFR = 0.725%) chance of dying if they are infected with Covid.
The significantly higher hospitalisation and fatality rates for those aged over 75 years old following a Covid infection emphasises the importance of the Spring 2024 booster campaign.
Spring 2024 Booster Campaign
The Spring 2024 booster campaign started on April 15. Considering the decline in vaccine efficacy after 15 weeks, a successful Spring 2024 booster campaign is important to protect the most vulnerable populations.
The following chart displays the weekly number of doses administered during the booster campaigns for England to date. The Spring campaigns are represented in green, the Autumn campaigns in brown, and doses administered outside of these campaigns are depicted in grey.
The chart shows the difference between the Spring and Autumn campaigns, each with its unique eligibility requirements. The Spring booster campaign is exclusively for individuals aged 75 and above, residents of care homes, and those with compromised immune systems. According to NHS England, approximately 7.3 million people qualify for the Spring campaign in England.
The Spring 2024 booster campaign in England is progressing at a similar pace as the Spring 2023 campaign, with just under 7.8 million doses administered within the first seven weeks.
However, progress continues to slow, with just 145,631 doses administered last week compared to 277,778 the week before. The chart below illustrates the weekly progress in coverage for the three eligible cohorts in England.
The chart shows that progress in vaccine coverage is slowing across all eligible cohorts and that disparities between the groups remain. In particular booster coverage for the under 75 year old immunosuppressed is low.
Just a reminder that the Spring 2023 booster campaign closes at the end of June.
From now until the 30 June, there are thousands of appointments available every day across the country, including at pharmacies and GP practices. Some areas also offer convenient walk-in options, with a full list of walk-in sites available online.
You can check to see if you are eligible and book a booster at the following link.
In conclusion
Despite the reduced level of data now published, the available information indicates that the recent rise in Covid levels has yet to start falling.
A new variant, KP.2, is widely circulating although, at present, it does not appear to have a significant relative growth advantage over other variants in circulation.
The Spring 2024 booster is progressing reasonably well, with just under 3.8 million doses administered so far. However, the immunosuppressed remain under vaccinated.
As always, if you have any comments on this Covid Situation Report or suggestions for topics to cover, please post a message below.
Appendix 1. Test positivity rates and prevalence
Positivity rates are derived from the results of hospital laboratory tests conducted on patients exhibiting symptoms of respiratory diseases. Test positivity is the percentage of patients who test positive for Covid of the total number of patients tested. Since the individuals tested for this measure are not a representative sample of the general population it differs from prevalence, which is derived from a representative sample of the population.
Test positivity rates, while not directly estimating the number of Covid infections in the general population, can be a valuable indicator of the infection trend. The panel chart below compares the weekly test positivity rate among hospital patients with respiratory symptoms to the prevalence of Covid in the general population, as reported in the Winter Infection Survey.
The chart shows that the weekly test positivity rates for patients with symptoms of respiratory infections follows the same pattern as the prevalence for Covid reported by the Winter Infection Survey. Since the Winter Infection Survey is based on a representative sample of the general population this supports using test positivity as a useful indicator for infection trends.