Laboratory reports of hepatitis A infections in England and Wales: October to December 2021
Published 23 January 2024
Applies to England and Wales
© Crown copyright 2024
This publication is licensed under the terms of the Open Government Licence v3.0 except where otherwise stated. To view this licence, visit nationalarchives.gov.uk/doc/open-government-licence/version/3 or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: psi@nationalarchives.gov.uk.
Where we have identified any third party copyright information you will need to obtain permission from the copyright holders concerned.
This publication is available at https://www.gov.uk/government/publications/hepatitis-a-england-and-wales-2021/laboratory-reports-of-hepatitis-a-infections-in-england-and-wales-october-to-december-2021
A total of 59 laboratory reports of new patients with hepatitis A were reported to the UK Health Security Agency (UKHSA) from the Second Generation Surveillance System (SGSS) during the fourth quarter of 2021 (October to December 2021) (see table 1 and figure 1).
This total was calculated after:
- exclusion of patients with samples sent to the Virus Reference Department (VRD) that were not confirmed as having had a recent hepatitis A virus infection (‘corrections’) and
- inclusion of additional patients confirmed by the VRD
This was a 23% decrease on the reports in the third quarter of 2021 (n=77) (figure 2). Fifty-one patients were reported through SGSS, after excluding corrections and before including the additional 8 confirmed cases identified by VRD (figure 1).
Table 1. Laboratory reports of hepatitis A in England and Wales, October to December 2021
| Age group | Females | Males | Total |
|---|---|---|---|
| Less than 1 year | 0 | 0 | 0 |
| 1 to 4 years | 2 | 2 | 4 |
| 5 to 9 years | 7 | 6 | 13 |
| 10 to 14 years | 1 | 3 | 4 |
| 15 to 24 years | 1 | 10 | 11 |
| 25 to 34 years | 1 | 7 | 8 |
| 35 to 44 years | 2 | 3 | 5 |
| 45 to 54 years | 1 | 3 | 4 |
| 55 to 64 years | 5 | 0 | 5 |
| 65 years and over | 0 | 5 | 5 |
| Total | 20 | 39 | 59 |
Note: Since Q1 2020, these reports have presented the number of cases excluding false positives and including additional cases identified by the VRD. Hence, numbers are not directly comparable to quarters prior to Q1 2020. It should be noted that false positives are more likely in older age groups.
The London region accounted for 34% (n=20) of reports, followed by the South East and West Midlands regions, each accounting for 17% (n=10). Age group and sex were well reported (no missing values, Table 1). There were 13 (22%) reports among those aged between 5 and 9 years and 11 (19%) in the 15 to 24 year age group. Males accounted for 66% of reports (n=39), and females 34% (n=20).
The following flowchart shows there were 94 reports of new patients with hepatitis A reported through SGSS. There were 2 corrections (laboratories informing the VRD that reports were false positives or due to reporting issues, or quality controls), leaving 92 laboratory reports of new patients through SGSS.
Samples from 74 patient were sent to VRD for confirmation and 41 cases were not confirmed. After excluding non-confirmed cases, 51 cases remained. Eight cases were confirmed in VRD but not reported through SGSS, giving a total of 59 new cases identified through SGSS or VRD in Q4 2021.
Figure 1. Flowchart of laboratory reports of hepatitis A by confirmation status (England and Wales), October to December 2021
Figure 2. Laboratory reports of hepatitis A by age and sex in England and Wales, October 2007 to December 2021
Notes:
- All figures are provisional and subject to change as records are updated.
- From Q1 2020, the central number of cases presented excludes false positives and includes additional cases identified by VRD. Hence, numbers are not directly comparable to previous quarters.
- It should be noted that false positives are more likely in older age groups.
Reference laboratory confirmation and phylogeny of hepatitis A infections
Of the 51 patients notified as having acute hepatitis A virus (HAV) infection during the second quarter of 2021, 32 had samples forwarded to VRD for genotyping. In addition, 8 patients were confirmed to have acute HAV infection that had not been reported through the laboratory reporting system although all the English cases were recorded in HPZone.
A total of 39 patient samples could be genotyped over this period: 5 were genotype IA (13%), 12 were genotype IB (31%) and 1 was genotype IIA (3%) and 21 genotype IIIA (54%). Of these samples, 27 were associated with travel (69%) and 12 had no travel history (31%).
This information is presented below as a phylogenetic tree (figure 3) where each sequence is represented by a dot followed by the patient region, and the week of sampling in brackets.
Figure 3. Phylogenetic tree of genotype IA, IB, and IIIA sequences October to December 2021 (n=39)
