Research and analysis

NOIDs causative agents: week 4 (week ending 25 January 2026)

Updated 26 January 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 2025/51 2025/52 2026/01 2026/02 2026/03 2026/04
Arboviruses            
West Nile Virus 1 1 - - 2 -
Bacillus            
Bacillus cereus 15 17 13 12 19 19
Bordetella            
Bordetella pertussis 2 2 2 3 5 4
Borrelia            
Borrelia burgdorferi 27 20 28 21 18 24
Borrelia sp 4 8 6 3 3 28
Brucella            
Brucella sp 3 1 - 3 - -
Burkholderia            
Burkholderia mallei - 1 - - - -
Burkholderia pseudomallei - - - 1 - -
Campylobacter            
Campylobacter coli 21 13 12 16 26 21
Campylobacter fetus - 1 - - - -
Campylobacter jejuni 284 241 170 197 264 194
Campylobacter other named - 3 2 1 3 2
Campylobacter rectus - - - - - 2
Campylobacter sp 850 640 620 730 788 923
Campylobacter upsaliensis 1 1 1 - 4 1
Campylobacter ureolyticus (bacteroides corrodens) 1 1 - 2 1 2
Chikungunya virus            
Chikungunya virus 2 - 1 1 3 1
Clostridium            
Clostridium botulinum - - - - - 1
Clostridium perfringens 32 51 34 51 51 28
Coronavirus            
Coronavirus 95 97 114 152 167 220
Human coronavirus 229e - 3 3 4 10 4
Human coronavirus hku1 - - 1 2 1 3
Human coronavirus nl63 - 1 2 - 2 1
Human coronavirus oc43 1 5 3 10 8 16
SARS-CoV-2 antibody void - 2 2 - - -
SARS-CoV-2 coronavirus (COVID-19) 625 547 652 674 717 673
SARS-CoV-2 coronavirus (COVID-19) indeterminate 35 10 14 27 28 17
SARS-CoV-2 IgG antibody negative 7 4 4 - - -
SARS-CoV-2 IgG antibody positive 38 26 24 28 22 57
SARS-CoV-2 total antibody negative - 12 12 8 16 4
SARS-CoV-2 total antibody positive 7 43 15 44 34 23
Corynebacterium            
Corynebacterium diphtheriae 5 4 3 3 2 4
Corynebacterium ulcerans 1 - - - - 2
Coxiella            
Coxiella burnetii - - - - - 1
Cryptosporidium            
Cryptosporidium hominis 11 6 4 9 8 4
Cryptosporidium parvum 34 29 17 11 8 13
Cryptosporidium sp 24 14 15 25 22 33
Cryptosporidium ubiquitum 2 2 - 1 - -
Entamoeba            
Entamoeba histolytica 4 3 2 1 7 2
Escherichia            
Escherichia coli O 157 6 3 3 5 5 1
Flaviviruses            
Dengue virus 3 4 1 6 3 1
Giardia            
Giardia intestinalis 2 2 - - 1 1
Giardia sp 148 84 84 112 128 131
Haemophilus            
Haemophilus influenzae 71 54 62 63 64 71
Hepatitis viruses            
Hepatitis A 12 15 3 19 14 11
Hepatitis B 274 172 224 198 243 253
Hepatitis C 601 160 190 217 202 199
Hepatitis D 4 2 4 4 3 11
Hepatitis E 31 25 26 32 38 43
Influenza virus            
Influenza A 7,879 6,045 6,061 5,524 4,202 3,051
Influenza B 51 47 56 50 57 65
Influenza indeterminate 7 23 38 15 30 5
Influenza ungrouped 321 228 141 112 75 39
Legionella            
Legionella pneumophila 12 3 2 8 8 5
Legionella sp 3 - 5 3 5 4
Listeria            
Listeria monocytogenes 2 6 4 2 2 3
Mycobacterium            
Mycobacterium tuberculosis 111 76 77 82 93 67
Neisseria            
Neisseria meningitidis 25 29 27 35 38 30
Orthopoxvirus            
Mpox virus positive 8 2 4 6 12 29
Paramyxoviruses            
Measles virus 10 9 9 10 16 6
Mumps virus 5 3 3 2 6 7
Plasmodium            
Plasmodium falciparum - - 1 - 1 9
Plasmodium malariae - - - - - 1
Plasmodium ovale - - - - 2 -
Plasmodium vivax - - - - - 1
Polyomavirus            
Polyomavirus BK 85 54 44 73 77 84
Polyomavirus JC 7 15 8 10 12 16
Polyomavirus untyped 14 9 8 8 20 16
Rickettsia            
Rickettsia prowazekii - 1 - - - -
Rickettsia spotted fever 1 1 - - - 1
Rickettsia tsutsugamushi - 1 - 1 - -
Rubella virus            
Rubella virus 2 1 2 5 2 1
Salmonella            
Other salmonellas 48 38 45 55 44 21
Salmonella enterica 6 - - - - -
Salmonella enteritidis 44 31 33 38 29 13
Salmonella infantis - 5 - - - -
Salmonella newport 8 - - - 5 -
Salmonella sp 35 16 9 17 75 128
Salmonella stanley - - - 5 - -
Salmonella typhi and paratyphi 7 5 9 14 14 7
Salmonella typhimurium 21 24 15 24 21 11
Salmonella virchow 6 - - - - -
Shigella            
Shigella boydii 1 2 1 1 - -
Shigella dysenteriae - - 1 - 2 -
Shigella flexneri 12 11 18 20 19 10
Shigella sonnei 42 14 17 23 15 12
Shigella sp 35 33 28 43 52 62
Streptococcus            
Streptococcus group A 51 57 64 71 55 75
Streptococcus pneumoniae 194 169 229 197 141 139
Vibrio            
Vibrio cholerae - - - 1 - -

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 2025/51 2025/52 2026/01 2026/02 2026/03 2026/04
Citrobacter              
Citrobacter spp IMP - - - - 1 -
  KPC - 1 - - 3 -
  NDM 2 1 2 - 2 -
  OXA48 1 3 2 2 8 1
  Other - 1 - - - -
Enterobacter              
Enterobacter cloacae complex IMP 2 3 3 3 6 -
  KPC 4 3 2 2 1 -
  NDM 16 7 3 11 5 2
  OXA48 4 11 4 6 3 1
  VIM 1 1 - 1 - -
  Other 3 1 1 3 1 -
Other enterobacter spp KPC 2 - - - - -
  NDM 1 - - - - -
  OXA48 - - - - - 1
Escherichia              
Escherichia coli IMP - - 1 1 - -
  KPC 3 3 7 7 2 -
  NDM 17 17 16 21 16 4
  OXA48 23 20 24 16 21 8
  VIM - - 2 - - -
  Other 1 2 4 2 2 1
Escherichia marmotae NDM 1 - - - - -
  Other 1 - - - - -
Klebsiella              
Klebsiella aerogenes NDM 1 - - - 1 -
  OXA48 1 1 - - 1 -
  Other - 1 - - - -
Klebsiella oxytoca IMP - 1 - - - -
  KPC 1 - - - - 2
  NDM - - 1 - 1 -
  OXA48 - - - 2 2 -
  VIM 1 - - - - -
Klebsiella pneumoniae IMP - - - - - 1
  KPC 3 6 4 8 7 1
  NDM 12 10 17 9 14 5
  OXA48 13 6 14 8 14 4
  VIM - - 1 1 2 -
  Other 2 - 1 1 2 1
Klebsiella pneumoniae subsp ozenae KPC - 2 - 1 - -
Klebsiella variicola KPC - - - - 1 -
  OXA48 - 1 - - - -
Leclercia              
Leclercia adecarboxylata KPC - - - - 1 -
Morganella              
Morganella morganii NDM - - 2 - - -
  OXA48 - 1 - - - -
Pantoea              
Pantoea septica OXA48 - 1 - - - -
Pluralibacter              
Pluralibacter gergoviae Other - - - - 1 -
Proteus              
Proteus mirabilis NDM - 1 1 2 1 -
  Other - - 2 2 3 -
Providencia              
Providencia stuartii OXA48 - - - 1 - -
Raoultella              
Raoultella spp OXA48 - - 1 - - -
Serratia              
Serratia marcescens/ureilytica NDM 1 - - - - -
  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 2025/51 2025/52 2026/01 2026/02 2026/03 2026/04
Acinetobacter              
Acinetobacter baumannii NDM 1 - - 1 - -
  Other 1 - - 1 - -
Pseudomonas              
Pseudomonas aeruginosa IMP - 1 - - 1 -
  NDM 1 1 1 1 2 1
  VIM 1 - 2 1 2 -
  Other 1 2 2 4 6 1
Pseudomonas alcaligenes VIM - 1 - - - -
Pseudomonas putida group VIM - - - - - 1
Pseudomonas stutzeri group VIM - - - - 1 -
Other              
  KPC - 1 - - - -
  NDM 1 - 1 1 - -
  OXA48 1 - 1 - 1 -