Microregistrar Infection Newsletter · Sunday 1 November 2026
Influenza B vaccine effectiveness across eight US seasons: B/Victoria protection fell to 39% in 2024–25, the first trivalent season.
A US Flu VE Network analysis in JID (Meeker J, Price A, Martin E and colleagues) used a test-negative design in ambulatory patients aged 6 months and over across eight seasons, 2016–17 to 2024–25 (2020–21 excluded). Of 65,773 participants, 3,629 influenza B cases were included in lineage-specific analyses (1,507 B/Yamagata; 2,122 B/Victoria). B/Victoria VE was 58% (95% CI 28–77%) in 2016–17, 51% (43–57%) in 2019–20, 78% (71–84%) in 2023–24 and 39% (14–56%) in 2024–25. B/Yamagata VE was 55% in 2016–17 and 49% in 2017–18.
2024–25 was the season trivalent vaccines containing B/Victoria returned after B/Yamagata stopped being detected globally. The authors conclude that vaccines protected against medically attended influenza B, but that VE varies by season and that genetic surveillance must continue to guide strain selection. With UK flu activity still low but expected to rise in November, it is a useful reference for this season’s influenza B questions.
Check before quoting: taken from the Crossref abstract only. The abstract doesn’t attribute the 2024–25 fall to the trivalent switch or to antigenic drift, and the wide 2024–25 interval (14–56%) overlaps earlier seasons. Only 6 of 10 season-lineage strata met the reporting threshold.
Counted from today’s digest. The Crossref sweep (online 31 Oct–1 Nov) found 6 new infection-relevant items (JID 3, OFID 1, JAC-AMR 1, NEJM 1); a correction and four non-infection NEJM pieces aren’t counted. Links are unique content links across the issue, not counting our two website links. It was a weekend: GOV.UK showed nothing from UKHSA, MHRA or DHSC after Friday evening, ECDC posted no news, there was no new WHO DON, and CIDRAP published nothing in the window.
Also today
The other headlines from today’s issue. Each card links to its source and to the full summary.
MMRV catch-up starts today
From 1 November a single free catch-up MMRV dose is offered to eligible children born 1 January 2020 to 31 August 2022 (runs to 31 March 2028).
Enable, don’t restrict, new antibiotics in ICU CRO infection
An expert narrative review proposes an AMS algorithm and argues for an enablement strategy for new agents in critically ill patients with carbapenem-resistant infections.
Recurrent TB in 8% of PLWH within two years of treatment
In 3,357 people with HIV in Andhra Pradesh, two-thirds of recurrences came within 12 months; viral non-suppression (aSHR 3.36) and no dolutegravir were the strongest predictors.
Cholera in Mbandaka: 129 cases, 14 deaths
A press report relayed by FluTrackers describes 129 cases and 14 deaths in two Mbandaka health zones within a few days. Not confirmed by WHO.
DRC: 77 new cases on 29 Oct; Nigeria suspects test negative
A DRC government relay reports 77 new cases and 34 deaths for 29 Oct. Two suspected Nigerian cases tested negative, and Saudi Arabia has suspended travel to and from Kenya.
C. diphtheriae & C. ulcerans interactive added
One new row dated 31 Oct now tops “Whats new?”: C diphtheriae & C ulcerans Interactive.
What we could not confirm
The lead comes from the JID abstract only. All Ebola, cholera and avian flu items in the window are FluTrackers or press relays: there’s still no new WHO DON since DON622 and no UKHSA outbreaks update. The Colombian returnee report (malaria, Ebola being ruled out) comes from a secondary account and is unconfirmed. Weekly X items such as Pakistan mpox and England’s first poultry H5N1 of the season are secondary reports. CDC HAN is still blocked, and ECDC’s CDTR archive still stops at week 42.
Microregistrar Moodle update
One new entry. We read the Microregistrar moodlecloud sheet (Index tab, “Whats new?”) directly this morning (1 Nov). Since the 31 Oct issue, one row dated 31 Oct has been added above the 30 Oct Green Book row we reported yesterday.
C. diphtheriae & C. ulcerans Interactive
The new top row in “Whats new?”. The sheet gives only the title; we haven’t opened the Moodle page itself. Moodle ›
Greenbook vaccine part 1 revision
Now the second entry; we reported it on 31 Oct. Sheet ›
The full list is in the Microregistrar moodlecloud sheet ›
Watched pages
We check nine pages every morning for anything new, compared with what we saw last time (checked on the morning of 1 Nov 2026). All nine were reached, and none has anything new, as expected on a weekend.
Health Protection Report (UKHSA)
No changeHPR 20(10) of 29 Oct is still the latest issue. HPR volume 20 ›
UK SMI News (RCPath)
No changeStill no open consultations and no new UK SMI documents. No Mail Sorter SMI forwards arrived. Consultations ›
UKHSA organisation page (GOV.UK)
No changeNothing new since Friday 30 Oct (the latest item was posted at 13:33 GMT). The HCID country risk page hasn’t changed since 22 Oct. UKHSA › · HCID risk ›
Journal of Antimicrobial Chemotherapy
No changeNo new JAC items in the Crossref sweep (online 31 Oct–1 Nov); the sister title JAC-AMR had one (see Journals). JAC advance articles ›
Agencies & guidance
A quiet weekend for agencies: nothing new from UKHSA, MHRA, DHSC or ECDC, and no new WHO DON. The MMRV catch-up programme starts today and #MedSafetyWeek starts tomorrow. Outbreak news came only through relays: Ebola in the DRC, cholera in Mbandaka and avian influenza in Canada.
Guidance changes
MMRV catch-up programme begins
From today until 31 March 2028, a single catch-up MMRV dose is offered to children born between 1 January 2020 and 31 August 2022 who haven’t had chickenpox or two doses of varicella vaccine. Routine MMRV at 12 and 18 months started on 1 January 2026. Yesterday’s issue covered the 2025 varicella baseline report (3,037 under-18 admissions). There was no new guidance in the window.
For paediatric ID, virology and IPC teams: expect eligibility and prior-disease questions this week. Unvaccinated infants and immunocompromised children still depend on VZIG/antiviral post-exposure pathways.
UKHSA / MHRA / England
No new UKHSA or DHSC infection publications
The latest UKHSA item on GOV.UK is from Friday 30 Oct. The week 45 flu and COVID-19 surveillance report (data to week 44) is announced but not yet out. The GOV.UK “Health protection” weekly digest email (31 Oct) led on FSA Joint Expert Group outputs; there were no Mail Sorter forwards.
#MedSafetyWeek runs 2–8 November
No new MHRA alerts in the window. The annual campaign encouraging suspected side-effect reporting, including for vaccines and anti-infectives, starts tomorrow.
ECDC / Europe
No ECDC news; CDTR archive still at week 42
The ECDC news feed has nothing after 29 Oct. The weekly threats archive still lists week 42 as the latest (weeks 43 and 44 are overdue). On X, ESCMID opened registration for an EUCIC course on behaviour change in IPC and stewardship.
Global
DRC reports 77 new cases for 29 Oct; attacks on responders; Nigerian suspects negative
- DRC (government, via FluTrackers): 77 new cases and 34 deaths for 29 Oct, plus 3 positive people at the Regideso point of entry across the river from the Central African Republic. The CAR link is unconfirmed.
- Security: press reports relayed by FluTrackers say two young doctors were killed in under 48 hours, and that the Bafwasende (Tshopo) Ebola treatment centre was burned down before it opened.
- Nigeria (NCDC, via FluTrackers): two suspected cases in the North-East tested negative; the national total stays at 1.
- Kenya: Saudi Arabia has suspended travel to and from Kenya. No new Kenyan case figures were reported in the window.
- Imported-case scares: a secondary account reports that Colombia’s health ministry has two returnees from the DRC with malaria, one of whom died, and that Ebola is being ruled out. No Ebola case is confirmed.
- UK: no imported cases; UKHSA’s risk assessment is unchanged (low).
There’s no new WHO DON since DON622 (23 Oct), no new UKHSA outbreaks report and no new CIDRAP Ebola article. The latest verified totals are still UKHSA’s (data to 25 Oct). Ebola doesn’t lead today under our once-a-week rule.
@FluTrackers (DRC) › · @FluTrackers (doctors) › · @FluTrackers (ETC) › · @FluTrackers (Nigeria) › · @FluTrackers (Saudi) › · @theinformant_x (Colombia) › · UKHSA OUM ›
Mbandaka cholera: 129 cases and 14 deaths
A press report (via FluTrackers) describes 129 cases and 14 deaths in two Mbandaka health zones (Équateur) within a few days. This comes on top of the Ebola response pressures in the DRC.
Press relay; not confirmed by WHO or the DRC ministry.
H5N1 in Canada; severe paediatric flu in Hong Kong
The Canadian government reported two commercial poultry outbreaks in Alberta, and British Columbia is monitoring rising wild-bird deaths. Hong Kong’s CHP reported a child with severe influenza A(H1) admitted to ICU.
FluTrackers relays; subtypes for the Canadian outbreaks are marked “H5N1?” by the relay and are unconfirmed.
@FluTrackers (Alberta) › · @FluTrackers (BC) › · @FluTrackers (Hong Kong) ›
WHO
No new Disease Outbreak News in the window
The latest is still DON622 (Ebola, 23 Oct).
CDC / US
No new EID articles; travel notices unchanged
EID’s early-release feed has nothing after the three 30 Oct articles we reported yesterday. The travel notice list is unchanged. The HAN archive was blocked again. CIDRAP published nothing in the window; US measles stands at 4,852 cases (CIDRAP, 30 Oct). The CDC Ebola travel attestation starts on 3 Nov.
Four more NWS infections in New Mexico
USDA reported four more New World screwworm infections in two New Mexico counties: a dog, two cattle and a fly (via FluTrackers).
Journals
New since the 31 Oct issue (online 31 Oct–1 Nov), from a Crossref sweep of the 19 watched titles. The Lancet titles, JAMA, CID, IJID, ICHE, AJIC, JAC, J Hosp Infect, J Infect, CMI, ARIC, AAC, JCM and Eurosurveillance had nothing new, and 4 of NEJM’s 5 items weren’t infection-related.
Journal of Infectious Diseases
Influenza B VE by lineage, US Flu VE Network, 2016–17 to 2024–25
Meeker J, Price A, Martin E and colleagues. A test-negative design in 65,773 outpatients with acute respiratory illness: 3,629 influenza B cases (1,507 B/Yamagata; 2,122 B/Victoria). B/Victoria VE: 58% (2016–17), 51% (2019–20), 78% (2023–24) and 39% (14–56%) in 2024–25, the first season trivalent vaccines were back in use. B/Yamagata VE: 55% (2016–17) and 49% (2017–18).
Takeaway: influenza B vaccination still protects against medically attended illness, but VE swings between seasons. Keep influenza B in the differential and in antiviral decisions even in vaccinated patients.
IgA-NS1 marks postnatal orthoflavivirus exposure but not protection from microcephaly
Castro-Meneses J, Castro-Trujillo S, Mejía W and colleagues. 164 Colombian mother–infant pairs with confirmed gestational ZIKV exposure. IgA-NS1 ELISAs had sensitivity/specificity of 94%/97% (ZIKV) and 86%/85% (DENV), with 26% DENV cross-reactivity against ZIKV NS1. There was no placental transfer and no association with CZS microcephaly.
Predictors of incident hepatic fibrosis in women with and without HIV
A new JID cohort study of incident fibrosis and steatotic liver disease-associated fibrosis (title only; we didn’t read the abstract).
OFID, JAC-AMR and NEJM
Responsible use of new antibiotics in critically ill patients with CRO infections
Eckmann C, Akova M, Antonelli M and colleagues. A narrative review and expert opinion. Barriers to new agents include selective susceptibility testing, limited availability, cost and resistance concerns. The authors propose an AMS algorithm that emphasises early diagnosis and appropriate therapy, and they favour enablement over restriction for MDR Gram-negative infection in critically ill patients, recognising that this needs substantial workforce and expertise.
Takeaway: a useful counterpoint for AMS teams that gate ceftazidime-avibactam, cefiderocol or aztreonam-avibactam behind approval. Rapid carbapenemase testing makes enablement safer. This is expert opinion, not trial evidence.
Recurrent TB and death after treatment in people with HIV, Andhra Pradesh
Allam R, Thogarucheeti M, Chava N and colleagues. 3,357 PLWH followed for 2 years after ATT: 270 (8.0%) had recurrent TB (5.1/100 PY) and 510 died (9.1/100 PY), with medians of 7 and 8 months. Predictors of recurrence: viral non-suppression (aSHR 3.36), no dolutegravir (2.62), delayed TPT (1.63), male sex (1.60) and no TPT (1.45).
Disseminated bartonellosis
Mahler C, Kälble F. An NEJM Images in Clinical Medicine case (no abstract).
On X
Sunday heavy check: six searches covering agency accounts (UKHSA, WHO, ECDC, CDC, MHRA, CIDRAP), societies and journals (ESCMID, IDSA, WHO/Europe), AMR/IPC and C. auris, UK vaccines and outbreaks, global outbreaks, and FluTrackers relays, looking back over the week (25 Oct to the morning of 1 Nov). Each item links to the post we read.
Week in review: UK and agencies
UKHSA: the varicella thread (3,037 under-18s hospitalised in 2025) and MMRV catch-up from 1 November @UKHSA ›; #UKHSAVirusWatch on what’s behind current coughs and sneezes. @UKHSA ›
NHS flu campaign: a GP provider says more than 10 million flu vaccinations have been given in England this autumn (secondary; not checked against NHS England). @HealthSsp ›
e-Bug (UKHSA): a new KS3 PSHE resource on vaccination, antibiotics, AMR and infection prevention. @eBug_UK ›
MHRA: #MedSafetyWeek (2–8 Nov) and Yellow Card reporting. @MHRAgovuk ›
WHO/Europe: an explainer on GISRS ahead of the European flu season. @WHO_Europe ›
AMR, IPC and stewardship
CDC AR Threats Report reaction: 9.7 million US drug-resistant infections and 50,800 deaths a year, with C. auris up 10-fold since 2019 (our 28 Oct lead). @IDSE_Online › A clinician thread lists the four urgent threats and the bedside takeaways. @LordAlirezaF ›
C. auris: a new publication on an EHR-integrated pathway for targeted admission screening. @elgujja ›
ESCMID: EUCIC onsite course on behaviour change in IPC and AMS @ESCMID ›, the AMS certificate course (register by 5 Nov) @ESCMID › and the #WAAW2026 webinar series. @ESCMID ›
IDSA: a webinar with ISHLT on cardiac device infections in immunocompromised hosts (10 Nov). @IDSAInfo ›
Outbreaks
Ebola: DRC 77 new cases and 34 deaths for 29 Oct @FluTrackers ›; Nigeria’s two suspects negative. @FluTrackers ›
H5N1, US dairy: a vet reports that Washington state records list 27 affected herds, up from 8 (28 Oct). @drcrystalheath ›
H5N1, England: a news share reports England’s first commercial poultry outbreak of the season (29 Oct). We haven’t confirmed it with Defra/APHA. @hanyshita ›
Mpox, Pakistan: secondary reports of 98 confirmed infections and 12 deaths in Sindh in 2026 @ThailandMedicaX ›, and four new local cases in Khyber Pakhtunkhwa. @ExpressNewsPK ›
Nipah, Kerala: a medical board will investigate whether expired remdesivir given to Nipah patients contributed to deaths @the_hindu ›. WHO, CEPI and PATH have drafted a Nipah severity score for vaccine trials (not yet validated). @realveritass ›
CIDRAP: US measles tops 4,800. @CIDRAP ›
Unverified: FluTrackers, news-share and individual accounts weren’t checked against primary sources. We found no ECDC posts this week, and we left out vaccine-sceptic reply threads and AI-bot replies.
What we could not confirm
We want you to know exactly where today’s issue has limits, so here are the 11 gaps we couldn’t close, plus the reports that simply weren’t out yet.
| Source | Issue |
|---|---|
| Lead (JID influenza B VE) | Abstract only. It doesn’t say why 2024–25 VE was lower, and the confidence interval is wide. US outpatient data may not apply to UK vaccines or populations. |
| Ebola | There was no new UKHSA, WHO or CIDRAP update. DRC, Nigeria, security and Saudi items come via FluTrackers, and the CAR point-of-entry positives are unconfirmed. The Colombia report is from a secondary account. |
| Cholera (DRC) | Press relay only; not confirmed by WHO or the DRC ministry. |
| Avian influenza | Canada and Hong Kong items are FluTrackers relays. The England poultry H5N1 report (29 Oct) is a news share we didn’t check against Defra/APHA. |
| Journals | Crossref abstracts only. The JID HIV fibrosis paper and the NEJM image have no abstract we read. Elsevier titles, the Lancet titles, AAC and JCM returned nothing, possibly because of weekend indexing lag. |
| X (weekly) | Six searches, max 25 posts each. Mpox (Pakistan), Nipah (Kerala) and NHS flu-uptake figures are secondary. |
| CDC | The HAN archive was blocked again (stub page). We didn’t check MMWR. |
| ECDC | The CDTR archive still shows week 42 (weeks 43 and 44 are missing). There was no ECDC news in the window. |
| CIDRAP | None of the ten per-topic feeds had an item in the window (weekend). |
| Moodle | The sheet gives only the title of the new entry; we didn’t open the Moodle page. |
| Mail Sorter / mailbox | No Mail Sorter forwards arrived. The only in-window email was the GOV.UK Health protection weekly digest. The X guide skill wasn’t available on the box, so the X tools were used directly. |
Not out yet
- UKHSA: week 45 flu/COVID-19 surveillance report (data to week 44); HCAI monthly data (4 Nov); measles (12 Nov); next outbreaks-under-monitoring report.
- ECDC: CDTR weeks 43 and 44 (overdue).
- WHO: the revised Ebola rapid risk assessment; the next DON and AFRO situation report.
- CDC: the Ebola travel attestation starts on 3 Nov.
- MHRA: #MedSafetyWeek runs 2–8 Nov.
Sources
What we checked for this issue. Every link in the issue was retrieved and checked during this run.
- Watched pages (9 of 9 checked on the morning of 1 Nov)
- Microregistrar moodlecloud Google Sheet (Index tab), read directly through the Sheets connector
- UKHSA, MHRA and DHSC on GOV.UK (search API); Green Book, HCID country risk, Health Protection Report and measles pages (content API)
- RCPath UK SMI consultations, UK SMI and Examinations pages; NICE published guidance
- Mail (microregistrar2021@gmail.com, read only): no Mail Sorter forwards; one GOV.UK digest
- ECDC: news feed and CDTR archive
- WHO Disease Outbreak News (API)
- CDC: travel notices (unchanged), HAN (blocked), EID early release (none new)
- CIDRAP per-topic feeds (Ebola, measles, avian flu, antimicrobial stewardship, influenza, HAI, COVID-19, pertussis, mpox, C. auris): none in the window
- Journal sweep (Crossref, online 31 Oct–1 Nov): Lancet Infect Dis, Lancet Microbe, NEJM, JAMA, CID, JID, OFID, IJID, ICHE, AJIC, JAC, JAC-AMR, J Hosp Infect, J Infect, CMI, ARIC, AAC, JCM, Eurosurveillance; EID checked separately
- X (Sunday heavy check): six searches over 25 Oct–1 Nov