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Research and analysis

NOIDs causative agents: week 21 (week ending 24 May 2026)

Updated 27 May 2026

The list of causative agents that laboratories must notify the UK Health Security Agency (UKHSA) about has been expanded to include additional notifiable organisms. These became reportable under the Health Protection (Notification) (Amendment) Regulations from 6 April 2025.

Publication of the additional causative agents will begin at a later date, once reporting development work has been undertaken to include them.

This report contains statistics of formal notifications of causative agent test results to UKHSA from diagnostic laboratories in England, under Regulation 4 of the Health Protection (Notifications) Regulations 2010.

The number of notifications in this report reflects test results provided from laboratories to UKHSA before UKHSA interprets or applies standardised case definitions to these test results. Individual test results will not always result in a confirmed diagnosis of a disease, therefore the notifications in this report should not be considered counts of cases and should be interpreted with caution.

Epidemiology reports including confirmed case numbers using standardised case definitions are published separately on a per pathogen or pathogen-group basis.

Laboratories in England have a statutory duty to notify UKHSA of the identification of the following causative agents:

  • Bacillus anthracis
  • Bacillus cereus
  • Bordetella pertussis
  • Borrelia spp
  • Brucella spp
  • Burkholderia mallei
  • Burkholderia pseudomallei
  • Campylobacter spp
  • Carbapenemase-producing Gram-negative bacteria
  • Chikungunya virus
  • Chlamydophila psittaci
  • Clostridium botulinum
  • Clostridium perfringens
  • Clostridium tetani
  • Corynebacterium diphtheriae
  • Corynebacterium ulcerans
  • Coxiella burnetii
  • Crimean-Congo haemorrhagic fever virus
  • Cryptosporidium spp
  • Dengue virus
  • Ebola virus
  • Entamoeba histolytica
  • Escherichia coli O 157
  • Francisella tularensis
  • Giardia spp
  • Guanarito virus
  • Haemophilus influenzae (invasive)
  • Hanta virus
  • hepatitis A
  • hepatitis B
  • hepatitis C
  • hepatitis D
  • hepatitis E
  • influenza virus
  • Junin virus
  • Kyasanur Forest disease virus
  • Lassa virus
  • Legionella spp
  • Leptospira interrogans
  • Listeria monocytogenes
  • Machupo virus
  • Marburg virus
  • measles virus
  • mpox virus
  • mumps virus
  • Mycobacterium tuberculosis complex
  • Neisseria meningitidis
  • Omsk haemorrhagic fever virus
  • Plasmodium falciparum
  • Plasmodium Knowlesi
  • Plasmodium Malariae
  • Plasmodium Ovale
  • Plasmodium Vivax
  • polio virus
  • Rabies virus
  • Rickettsia spp
  • Rift Valley fever virus
  • Rubella virus
  • Sabia virus
  • Salmonella spp
  • SARS coronavirus
  • Shigella spp
  • Streptococcus group A (invasive)
  • Streptococcus pneumoniae (invasive)
  • Varicella zoster virus
  • Variola virus
  • Vibrio cholerae
  • West Nile virus
  • Yellow fever virus
  • Yersinia pestis

Statutory notifications of causative agents, grouped by root organism

Totals for the current week compared to the previous 5.

Week notification received 2026/16 2026/17 2026/18 2026/19 2026/20 2026/21
Arboviruses            
West Nile Virus - - - - 2 -
Bacillus            
Bacillus cereus 23 27 21 33 28 18
Bordetella            
Bordetella pertussis 2 4 5 4 4 5
Borrelia            
Borrelia burgdorferi 33 19 29 19 21 39
Borrelia other named - - 1 - - -
Borrelia sp 1 5 6 5 1 2
Brucella            
Brucella sp 1 - - 2 1 -
Campylobacter            
Campylobacter coli 24 26 25 30 27 33
Campylobacter curvus - - - - 1 -
Campylobacter fetus 1 1 - 1 - -
Campylobacter gracilis - - 1 - - -
Campylobacter jejuni 244 296 333 266 352 374
Campylobacter lari - - - - 1 -
Campylobacter other named 2 5 - 1 2 6
Campylobacter rectus 1 - - - - 1
Campylobacter sp 872 1,144 1,021 873 1,080 1,151
Campylobacter upsaliensis - 3 - 2 - 1
Campylobacter ureolyticus (bacteroides corrodens) 2 3 - - 1 1
Chikungunya virus            
Chikungunya virus 1 2 3 2 1 -
Clostridium            
Clostridium perfringens 35 44 45 40 50 39
Coronavirus            
Coronavirus 115 80 98 79 70 66
Human coronavirus 229e 8 5 1 4 - 3
Human coronavirus hku1 1 2 3 2 - -
Human coronavirus nl63 3 2 7 2 2 3
Human coronavirus oc43 1 2 9 - - 1
SARS-CoV-2 antibody void - - - - 2 -
SARS-CoV-2 coronavirus (COVID-19) 249 196 183 262 170 173
SARS-CoV-2 coronavirus (COVID-19) indeterminate 3 9 10 5 8 2
SARS-CoV-2 IgG antibody negative - - - - 4 1
SARS-CoV-2 IgG antibody positive 31 33 12 20 31 36
SARS-CoV-2 total antibody negative 1 - - - - -
SARS-CoV-2 total antibody positive 12 7 7 4 6 9
Corynebacterium            
Corynebacterium diphtheriae 6 4 2 7 8 6
Corynebacterium ulcerans 1 - 1 - 2 2
Coxiella            
Coxiella burnetii 1 - - - - -
Cryptosporidium            
Cryptosporidium cuniculus - - 1 1 - -
Cryptosporidium hominis 3 4 4 2 6 4
Cryptosporidium meleagridis 2 - - 1 - -
Cryptosporidium parvum 69 80 83 53 35 11
Cryptosporidium sp 56 78 58 51 49 61
Cryptosporidium ubiquitum 1 - - - - -
Cryptosporidium viatorum 1 - - - - -
Entamoeba            
Entamoeba histolytica 3 3 3 4 4 3
Escherichia            
Escherichia coli O 157 5 13 11 12 12 3
Flaviviruses            
Dengue virus 1 5 3 5 7 5
Giardia            
Giardia intestinalis - 15 5 - - 1
Giardia sp 145 139 126 104 135 165
Haemophilus            
Haemophilus influenzae 89 55 60 54 56 65
Hepatitis viruses            
Hepatitis A 15 11 7 12 17 14
Hepatitis B 275 247 284 209 287 306
Hepatitis C 232 244 227 215 246 224
Hepatitis D 8 12 4 6 5 10
Hepatitis E 50 30 33 27 43 44
Influenza virus            
Influenza A 229 187 170 167 123 128
Influenza B 58 70 65 79 71 76
Influenza indeterminate 1 2 3 - 2 1
Influenza ungrouped 7 4 3 4 - 10
Legionella            
Legionella longbeachae - - - - - 1
Legionella other named - - - - 1 -
Legionella pneumophila 4 6 5 14 4 6
Legionella sp 1 4 1 6 7 3
Leptospira            
Leptospira interrogans - - 1 - - -
Listeria            
Listeria monocytogenes 4 1 6 2 2 3
Mycobacterium            
Mycobacterium tuberculosis 108 93 126 106 112 87
Neisseria            
Neisseria meningitidis 39 33 42 32 29 25
Orthopoxvirus            
Mpox virus positive 16 12 10 11 11 10
Paramyxoviruses            
Measles virus 40 30 21 35 30 51
Mumps virus 6 5 10 7 2 4
Plasmodium            
Plasmodium falciparum 1 - - - 21 -
Plasmodium malariae - - - - 2 -
Plasmodium ovale - - - - 3 -
Plasmodium vivax - - - - 1 -
Polyomavirus            
Polyomavirus BK 84 71 75 58 91 78
Polyomavirus JC 15 9 13 7 12 18
Polyomavirus untyped 13 14 14 12 29 19
Rickettsia            
Rickettsia prowazekii - - - 1 - -
Rickettsia rickettsii - - 1 1 1 -
Rickettsia spotted fever - 1 2 - - -
Rickettsia tsutsugamushi - 1 1 - - 1
Rubella virus            
Rubella virus 5 4 1 5 3 3
Salmonella            
Other salmonellas 63 64 64 70 43 19
Salmonella bovis-morbificans 5 10 - 5 - -
Salmonella enterica - 6 - 5 9 -
Salmonella enteritidis 61 63 63 55 34 20
Salmonella heidelberg - - 7 - - -
Salmonella infantis - 6 5 - - -
Salmonella newport 8 15 11 5 - -
Salmonella sp 18 27 21 32 95 174
Salmonella typhi and paratyphi 13 27 19 15 7 14
Salmonella typhimurium 24 31 26 30 21 10
Salmonella virchow - 5 6 - 5 -
Shigella            
Shigella boydii 1 1 1 - 1 1
Shigella dysenteriae - 1 - - 2 -
Shigella flexneri 14 23 14 18 13 13
Shigella sonnei 20 19 13 17 16 14
Shigella sp 46 52 65 24 46 50
Streptococcus            
Streptococcus group A 42 72 43 60 58 38
Streptococcus pneumoniae 132 124 100 129 106 114
Vibrio            
Vibrio cholerae - - 1 1 1 3

Carbapenemase-producing Enterobacterales (CPE)

For all Carbapenemase-producing Gram-negative organisms, the reports are de-duplicated by first mention of organism species and resistance mechanism by person in a rolling 52-week period.

Note: the numbers presented here do not include specimens that have been referred to the Antimicrobial Resistance and Healthcare Associated Infections (AMRHAI).

Week notification received 2026/16 2026/17 2026/18 2026/19 2026/20 2026/21
Citrobacter              
Citrobacter spp IMP 1 - - - - -
  KPC - 1 1 1 - -
  NDM 2 - 1 1 3 -
  OXA48 2 4 - 1 1 -
  Other 1 3 - - - -
Enterobacter              
Enterobacter cloacae complex IMP 2 1 1 2 - 1
  KPC 4 3 2 6 4 -
  NDM 10 6 8 6 6 2
  OXA48 1 3 4 7 5 -
  Other 1 3 2 1 2 -
Other enterobacter spp OXA48 - - - - 1 -
Escherichia              
Escherichia coli IMP 3 1 1 - 1 1
  KPC 2 1 1 - 4 2
  NDM 30 23 16 13 19 -
  OXA48 25 21 22 21 26 1
  VIM 2 - 1 - - -
  Other 6 4 4 1 1 1
Klebsiella              
Klebsiella aerogenes KPC - - - 1 - -
Klebsiella oxytoca KPC - 1 - 4 1 -
  NDM - 2 1 1 - -
  OXA48 1 5 1 1 - -
  Other - 1 1 1 - -
Klebsiella pneumoniae IMP 1 1 2 - 1 -
  KPC 6 10 6 4 2 3
  NDM 4 8 5 4 13 2
  OXA48 10 7 16 6 5 3
  VIM - - 2 - - -
  Other 2 1 1 1 2 1
Other klebsiella spp NDM - - - 1 - -
  OXA48 - - - 2 - -
  Other - - - 1 - -
Leclercia              
Leclercia adecarboxylata KPC - - - 1 - -
  NDM - - - 1 - -
Morganella              
Morganella morganii OXA48 - - - - 2 -
Proteus              
Proteus mirabilis NDM 2 1 3 2 - -
  Other 1 1 2 1 - -
Raoultella              
Raoultella ornithinolytica OXA48 - - - 1 - -

Other carbapenemase-producing Gram-negative organisms

For all Carbapenemase-producing Gram-negative organisms, the reports are de-duplicated by first mention of organism species and resistance mechanism by person in a rolling 52-week period.

Note: the numbers presented here do not include specimens that have been referred to.

Week notification received 2026/16 2026/17 2026/18 2026/19 2026/20 2026/21
Acinetobacter              
Acinetobacter baumannii NDM 1 - 1 1 - -
  Other 1 - - 1 - 1
Other acinetobacter spp NDM 1 - - - - -
Pseudomonas              
Pseudomonas aeruginosa IMP 1 - - - - -
  NDM 2 1 1 2 3 -
  VIM - 1 - - 1 -
  Other 2 2 4 1 1 1
Pseudomonas putida group VIM - - - 1 - -
Other              
  NDM - 1 1 - - -