Research and analysis

NOIDs causative agents: week 16 (week ending 19 April 2026)

Updated 20 April 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 2026/11 2026/12 2026/13 2026/14 2026/15 2026/16
Arboviruses            
West Nile Virus - - 1 - - -
Bacillus            
Bacillus cereus 26 17 23 20 20 23
Bordetella            
Bordetella pertussis 2 2 1 2 3 2
Borrelia            
Borrelia burgdorferi 11 26 18 13 17 31
Borrelia other named - 1 - - - -
Borrelia sp 3 9 4 2 3 1
Brucella            
Brucella sp - - - 3 1 1
Campylobacter            
Campylobacter coli 25 25 30 18 20 21
Campylobacter curvus 1 1 - - - -
Campylobacter fetus 1 - 2 - - 1
Campylobacter jejuni 245 299 317 232 209 202
Campylobacter other named 2 - 1 3 5 2
Campylobacter rectus - - 1 2 1 -
Campylobacter sp 892 889 1,001 901 767 911
Campylobacter upsaliensis 1 1 - - 1 -
Campylobacter ureolyticus (bacteroides corrodens) 2 1 1 1 1 2
Chikungunya virus            
Chikungunya virus 1 4 3 1 - 1
Clostridium            
Clostridium perfringens 43 43 29 44 26 35
Coronavirus            
Coronavirus 207 195 186 152 102 114
Human coronavirus 229e 7 4 6 4 8 8
Human coronavirus hku1 1 4 4 1 5 1
Human coronavirus nl63 3 8 3 4 2 3
Human coronavirus oc43 13 14 10 5 5 1
SARS-CoV-2 coronavirus (COVID-19) 492 494 507 395 370 249
SARS-CoV-2 coronavirus (COVID-19) indeterminate 24 13 23 8 3 3
SARS-CoV-2 IgG antibody negative 1 - - 1 - -
SARS-CoV-2 IgG antibody positive 41 43 30 11 18 31
SARS-CoV-2 total antibody negative 4 - - - - 1
SARS-CoV-2 total antibody positive 11 12 10 7 5 12
Corynebacterium            
Corynebacterium diphtheriae 7 6 2 4 5 5
Corynebacterium ulcerans - 1 5 - - 1
Coxiella            
Coxiella burnetii 3 - - - - 1
Cryptosporidium            
Cryptosporidium cuniculus - 1 - 1 - -
Cryptosporidium hominis 3 4 4 2 2 -
Cryptosporidium meleagridis - 1 - - - -
Cryptosporidium parvum 33 36 33 29 24 5
Cryptosporidium sp 38 27 30 31 48 127
Cryptosporidium ubiquitum - 1 3 1 - -
Entamoeba            
Entamoeba histolytica 2 5 - 1 1 3
Escherichia            
Escherichia coli O 157 4 3 7 4 4 1
Flaviviruses            
Dengue virus 5 2 9 5 2 1
Giardia            
Giardia intestinalis 1 2 1 1 1 -
Giardia sp 126 121 143 135 94 145
Haemophilus            
Haemophilus influenzae 59 76 53 64 54 86
Hepatitis viruses            
Hepatitis A 12 12 10 9 13 15
Hepatitis B 234 249 264 220 188 249
Hepatitis C 250 210 217 218 177 218
Hepatitis D 6 3 6 8 3 8
Hepatitis E 37 37 31 39 42 50
Influenza virus            
Influenza A 335 304 258 259 242 231
Influenza B 48 50 51 60 58 59
Influenza indeterminate 4 8 - 1 1 1
Influenza ungrouped 11 5 1 4 7 7
Legionella            
Legionella cherrii 1 - - - - -
Legionella pneumophila 4 8 6 6 6 4
Legionella sp 5 1 4 3 2 1
Listeria            
Listeria monocytogenes 9 8 5 7 5 3
Mycobacterium            
Mycobacterium tuberculosis 92 101 122 91 78 98
Neisseria            
Neisseria meningitidis 29 51 26 26 17 40
Orthopoxvirus            
Mpox virus positive 20 28 9 11 11 16
Paramyxoviruses            
Measles virus 17 27 25 27 38 40
Mumps virus 8 4 7 6 2 6
Plasmodium            
Plasmodium falciparum - 1 - - 1 1
Polyomavirus            
Polyomavirus BK 80 74 77 78 43 83
Polyomavirus JC 10 11 11 16 7 15
Polyomavirus untyped 10 25 20 8 17 13
Rickettsia            
Rickettsia prowazekii 1 - - - - -
Rickettsia rickettsii - - 1 - - -
Rickettsia sp 1 - - - - -
Rickettsia spotted fever - - - - 1 -
Rickettsia tsutsugamushi - 1 - - 1 -
Rubella virus            
Rubella virus 2 5 2 1 4 5
Salmonella            
Other salmonellas 56 67 66 53 27 13
Salmonella anatum - - - - 6 -
Salmonella braenderup - 5 - - - -
Salmonella enteritidis 39 46 22 27 13 13
Salmonella heidelberg 8 - - - - -
Salmonella java 6 - - - - -
Salmonella kentucky - 5 - - - -
Salmonella newport - 6 - - - -
Salmonella sp 15 22 14 39 49 149
Salmonella stanley - 7 6 - - -
Salmonella typhi and paratyphi 21 14 14 12 12 10
Salmonella typhimurium 32 25 28 32 18 7
Shigella            
Shigella boydii 1 - 2 1 - -
Shigella dysenteriae - 1 - 1 1 -
Shigella flexneri 18 16 16 16 7 7
Shigella sonnei 15 10 10 12 8 14
Shigella sp 64 66 57 38 36 60
Streptococcus            
Streptococcus group A 54 73 64 73 60 37
Streptococcus pneumoniae 117 107 162 123 145 128
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 2026/11 2026/12 2026/13 2026/14 2026/15 2026/16
Citrobacter              
Citrobacter spp IMP - 1 1 1 - -
  KPC 1 - - 2 1 -
  NDM 1 - 2 3 2 -
  OXA48 4 3 3 2 1 -
  VIM 2 - - - - -
  Other - - - 1 - -
Enterobacter              
Enterobacter cloacae complex IMP 5 5 - 3 3 -
  KPC - 1 3 4 1 -
  NDM 11 5 9 7 13 1
  OXA48 5 3 4 2 3 -
  VIM 1 - - - - -
  Other 2 1 2 1 2 -
Other enterobacter spp IMP - - 1 - - -
  NDM - 1 - - - -
  Other 1 1 - - - -
Escherichia              
Escherichia coli IMP 2 2 1 2 2 -
  KPC 2 3 4 4 1 -
  NDM 18 16 28 17 18 7
  OXA48 26 24 21 14 21 7
  VIM - - - - 2 -
  Other 2 4 5 5 4 1
Escherichia vulneris KPC - - - - 1 -
Klebsiella              
Klebsiella aerogenes NDM - - 1 - - -
Klebsiella oxytoca KPC 1 - 1 - 1 -
  NDM - 1 2 - - -
  OXA48 1 - 1 - 1 -
Klebsiella pneumoniae IMP 1 1 2 - 2 -
  KPC 1 3 5 5 5 4
  NDM 11 8 9 10 9 1
  OXA48 11 8 9 9 9 2
  VIM 1 1 - - 2 -
  Other 2 3 2 2 1 -
Klebsiella variicola OXA48 - - 1 - - -
Other klebsiella spp NDM - - - 1 1 -
  OXA48 1 - - - - -
Leclercia              
Leclercia adecarboxylata IMP 1 - - - - -
Morganella              
Morganella morganii NDM - 1 1 - - -
  OXA48 1 - - - - -
  Other - - 1 - - -
Proteus              
Proteus mirabilis NDM 3 1 - 1 - -
  Other 2 1 - - - -
Raoultella              
Raoultella spp KPC - - - - 1 -
Serratia              
Serratia marcescens/ureilytica KPC 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 2026/11 2026/12 2026/13 2026/14 2026/15 2026/16
Acinetobacter              
Acinetobacter baumannii NDM 1 - 1 1 1 -
  Other 1 - - 1 - -
Other acinetobacter spp NDM - - 1 - - -
  Other - - 1 - - -
Pseudomonas              
Pseudomonas aeruginosa NDM 2 - - 1 - 1
  VIM - - - - 2 1
  Other 1 4 1 2 4 -
Pseudomonas putida group NDM 1 - - - - -
  VIM 1 - - - - -
Pseudomonas stutzeri group Other - 1 - - - -
Other              
  NDM - - - - 1 -