Research and analysis

Laboratory confirmed cases of measles, rubella and mumps in England: January to March 2025

Published 26 June 2025

Applies to England

Introduction

Measles, mumps and rubella are notifiable diseases; healthcare professionals are legally required to inform their local health protection team (HPT) of any suspected case. National enhanced surveillance including oral fluid (OF) testing of all suspected cases is provided through the Virus Reference Department (VRD) at Colindale to support and monitor progress towards World Health Organization (WHO) measles and rubella elimination targets (1).

Two WHO indicators are of prime importance for measuring the performance of national measles and rubella surveillance systems. These are:

1. The rate of laboratory investigations (at least 80% of suspected cases)
2. The annual rate of discarded cases (at least 2 per 100,000 population)

In order to achieve these targets, the focus of the UK Health Security Agency (UKHSA) is to ensure that all suspected cases are appropriately tested. Oral fluid and serology samples are the only two samples considered adequate by WHO for confirming or discarding a suspected measles or rubella case. Recent infection is confirmed by measuring the presence of IgM/IgG antibodies or detecting viral RNA (by PCR) in these samples.

Samples that have been confirmed positive for measles or rubella in a proficient laboratory (this includes local laboratories as well as the National Reference Laboratory) are included in this report. Samples that are referred to, or tested at, the National Reference Laboratory are further sequenced and entered on the WHO global Measles Nucleotide Surveillance (MeaNS) or the Rubella Nucleotide Surveillance (RubeNS) system, respectively, which are hosted at the National Reference Laboratory. Genotyping and further characterisation of measles and rubella is used to support investigation of transmission pathways and sources of infection.

Data presented here is for the first quarter of 2025 (January to March). Analyses are executed using the onset date of a rash or, more broadly, symptoms, and regional breakdown figures relate to the Government Office Regions. Measles hospitalisation statistics have been derived from the Secondary Users Service and Emergency Care Data Sets.

Historical annual and quarterly measles, mumps and rubella epidemiological data is available from 2013 onwards:

• Measles: confirmed cases
• Mumps: confirmed cases
• Rubella: confirmed cases

The results from all samples tested at Colindale are reported to our laboratory information system MOLIS. The results are then reported back to the respective general practitioner (GP) and local HPT.

Overview

Table 1. Total suspected cases of measles, mumps and rubella reported to HPTs with breakdown of: a) number of suspected cases b) proportion tested by Oral Fluid (OF); c) other samples referred onto the Virus Reference Department (VRD) Colindale from local NHS hospital and private laboratories; d) cases confirmed at the VRD; e) cases confirmed at regional, local NHS hospital and private laboratories only; f) discard rate (measles and rubella only): weeks 1 to 14 of 2025

Notified as	Total suspected cases*	Number (%) tested by OF**	Other samples received by VRD	Number of samples IgM positive or viral detection in VRD	Number locally confirmed	Discard rate based on negative tests per 100,000 population (all samples)***
Measles	950	435 (45.8)	93	182	44	1.25
Mumps	1,051	616 (58.6)	49	20	19	1.75
Rubella	32	16 (50)	1	0	0	0.06

*This represents all cases reported to HPTs in England; that is: possible, probable, confirmed and discarded cases on CIMS.

**The target set by WHO is 80% for measles and rubella only.

***The WHO has set a target for the annual discard rate of 2 cases per 100,000 population, which translates to a quarterly target of 0.5 per 100,000. It should be noted that we have proportionally adjusted the annual target, to ensure there is consistent testing across each quarter. This ensures we regularly achieve the target, rather than batch testing in one quarter to achieve the annual discard rate. The discard rate is based only on VRD testing only because local negative tests are not routinely reported to UKHSA. Therefore, this is likely to be an underestimation of the true discard rate.

Measles

In the period between January and March 2025, there were 226 laboratory confirmed cases of measles reported in England, a 25% decrease compared to the previous quarter (n=302) (2) (Figure 1). The cases this quarter were mainly caused by outbreaks in London, the South West and Yorkshire and Humber regions. Details of the most recent epidemiology is available (3).

Of the 226 cases reported this quarter, 33 (14.6%) were classified as imported and 7 (3.5%) as import-related. The majority, 61.1% (138 of 226) of cases were in children aged 10 years or younger. Six cases (2.7%) had been previously vaccinated with one dose of the MMR vaccine and 5 (2.2%) with at least two doses.

Using NHS number, 174 individuals linked to the secondary care datasets in the period 5 days before to 10 days after their onset of measles symptoms. Of these 174, 33.3% of cases attended A&E only with no admission (58/174) and 33.3% of cases were admitted (58/174). 17.2% of cases had a primary measles-related reason for admission (30/174).

In Scotland, there were 23 laboratory-confirmed measles cases reported. In 2024 alone, there was a total of 24 laboratory-confirmed measles cases; of these, 2 were classed as imported and a subsequent 12 cases as import-related. In Northern Ireland, there were 3 laboratory-confirmed measles cases and 1 in Wales, which was classed as imported.

Figure 1. Laboratory confirmed cases of measles by month of onset of rash or symptoms reported, London and England: January 2012 to March 2025

Across the WHO European Region there has been an increase in measles infections since 2022 (4). In 2024, there were 127,350 cases reported, double that reported in 2023 (n=61,070) and the highest since 1977 (5, 6). Measles in this region accounted for one third of all cases globally. This increasing trend follows a reduction in vaccination coverage since the COVID-19 pandemic (5). Romania (n=30,692), Kazakhstan (n=28,147) and the Russian Federation (n=22,076) contributed the most measles cases in 2024 (7). Globally, activity is also present across WHO African, Eastern Mediterranean and South-East Asian regions. Between January and March 2025, cases have been the highest in Yemen (n=10,794), India (n=7,201) and Pakistan (n=6,217) (8). Importations remain a large threat to measles resurgence in under-vaccinated communities (6).

All suspected cases of measles and rubella should be reported promptly to HPTs, a risk assessment conducted and an Oral Fluid Kit (OFK) sent for confirmatory testing even if local diagnostic testing is underway. This quarter, an oral fluid sample was returned for 435 (45.8%) of all suspected measles cases reported in England and, therefore, did not meet the WHO target of 80% (Table 1).

Mumps

In England, there were 39 laboratory confirmed mumps infections in the period between January to March, more than double since the last quarter (n=17) (1).

Eight (21%) of the 39 cases this quarter were in children under the age of 15 years. Of these, 37.5% (3 of 8) were vaccinated with one dose of MMR, and 37.5% (3 of 8) had received at least two doses. Of the 31 cases in those aged 15 years and older, 6.5% (2of 31) were vaccinated with at least one dose of MMR, and 16.1% (5 of 31) had received at least two doses. The remaining cases had no vaccine recorded.

Figure 2. Laboratory confirmed cases of mumps by quarter, England: January 2012 to March 2025

Rubella

There were no laboratory confirmed cases of rubella reported in this quarter.

References

1. Public Health England (2019). UK Measles and rubella elimination strategy 2019

2. UKHSA (2025). ‘Laboratory confirmed cases of measles, rubella and mumps in England: October to December 2024’. Health Protection Report volume 19 number 5

3. UKHSA (2025). ‘Confirmed cases of measles in England by month, age, region and upper tier local authority: 2025’

4. Muscat M, Ben Mamou M, Reynen-de Kat C, Jankovic D, and others (2024). ‘Progress and challenges in measles and rubella elimination in the WHO European Region’. Vaccines: volume 12, number 6

5. WHO Europe (2025). European Region reports highest number of measles cases in more than 25 years

6. UNICEF (2024). Measles cases across Europe continue to surge, putting millions of children at risk

7. WHO (2024). Measles/Rubella (MR) Dashboard. Summary table: cases by year and final classification

8. US Centers for Disease Control and Prevention (June 2025). Global Measles Vaccination – Global Measles Outbreaks.