BMJ Public Health (Review): Public health risks and control measures associated with live animal and animal product trade in traditional food markets in low- and middle-income countries

#19,371

In the summer of 2025 we looked at a review article (see J. Virology: Zoonotic Disease Risk at Traditional Food Markets) by Frida E. Sparaciari, Cadhla Firth, Erik A. Karlsson, and Paul F. Horwood which concluded that traditional food markets (TFMs) provide essential community services (both economic and social), but they can also be hotspots for zoonotic disease transmission.

 

Live bird markets (LBMs) have long been linked to human exposure to (and infection by) avian influenza viruses, so much so that in 2014, in CDC: Risk Factors Involved With H7N9 Infection, we looked at a case-control study that pretty much nailed visiting LBMs as the prime risk factor for infection.

Four years ago, in Zoonoses & Public Health: Aerosol Exposure of Live Bird Market Workers to Viable Influenza A/H5N1 and A/H9N2 Viruses, Cambodia, we looked at a study that documented high levels of H5 & H9 viruses in the air at a Cambodian LBM during the `high season' for avian flu, and more importantly, that a large percentage remained viable (and infectious).

In low and middle-income countries (LMICs) - where home refrigeration is less common - the ability to buy freshly killed poultry is often viewed as a necessity. 

Larger, more modern cities like Hong Kong have gone to great lengths to regulate and restrict live bird markets, while early in 2025, Shanghai suspended Live Poultry Sales altogether.

During past avian flu outbreaks - when authorities ordered LBMs closed - clandestine and unregulated markets sometimes sprang up, which only exacerbated the problem.

The authors of the above mentioned J.Virology review are back today (with several other contributors) with a follow-up scoping review based on 87 studies published between 2017 and the end of 2025 that reported on public health outcomes, risk factors or control measures associated with TFMs in LMICs.

Most of these studies centered on TFMs in China and Bangladesh, and while avian flu was the primary focus, other public health risks (primarily bacterial zoonoses, e.g. Campylobacter spp, Salmonella spp, and multi-drug resistant E. coli) were also considered.

While the authors offer up a number of suggestions that may help reduce the risks, this is a complex and varied problem, and solutions will likely have to be tailored to each TFM.   

Follow the link to read the review in its entirety. 

Public health risks and control measures associated with live animal and animal product trade in traditional food markets in low- and middle-income countries: a scoping review

Author affiliations• Frida E Sparaciari1 2,  Alfonso I Vargas Huaco3 4,  Charifa Zemouri5,  Anna Signe Fomsgaard1 2, Wei Ning Chen3 4, Cadhla Firth2 6, Paul F Horwood2 7, Erik Karlsson1 8

        BMJ Public Health 2026;4:e006159. doi:10.1136/bmjph-2026-006159 

Abstract

Introduction 

Traditional food markets (TFMs) support food security and livelihoods in low- and middle-income countries (LMICs), but the trade of live animals and products of animal origin may facilitate zoonotic and foodborne disease transmission. Evidence on associated risks and control measures remains fragmented across pathogens, market types and interventions. This scoping review maps the literature on zoonotic and foodborne public health risks, risk factors and control measures related to the trade of live animals and animal products in TFMs in LMICs.

Methods 

Web of Science, PubMed and Scopus were searched on 24 April 2026 for primary, English-language studies published from 1 January 2017 to 31 December 2025. Eligible studies reported public health outcomes, risk factors or control measures associated with TFMs in LMICs. Reviewers screened titles/abstracts and full texts against predefined criteria, resolving disagreements by consensus. Data were charted and checked using a standardised pro forma; no methodological quality appraisal was conducted.

Results 

87 studies were included; 61 (70.1%) reported public health risks and 35 (40.2%) examined control measures, with 9 (10.3%) addressing both domains. Most studies were observational and focused on poultry markets and avian influenza viruses (AIVs), particularly at the human–market interface. Reported risks included occupational exposure among market workers, exposure among community members and contamination of animal products and market environments.

Common risk factors included poor hygiene, weak biosecurity, on-site slaughter, species mixing, inadequate waste management, prolonged animal holding and unsafe handling. Control measures included market closure, rest days, species separation, cleaning and disinfection, infrastructure improvements and policy-based interventions such as China’s ‘1110’ policy.

Across distinct studies, several measures were associated with lower pathogen detection or modelled infection estimates, whereas other findings were non-significant or inconsistent. Implementation was constrained by economic losses, limited infrastructure, weak enforcement, low awareness and poor adherence to protective practices.

Conclusions 

TFMs are important human–animal–environment interfaces where zoonotic and foodborne risks arise from interacting biological, structural and behavioural factors. The findings from this scoping review provide a rationale for context-specific, multilevel One Health approaches combining infrastructure improvements, biosecurity, surveillance, regulation, compensation and vendor engagement. However, because most evidence was observational and concentrated on AIV-focused poultry markets, the effectiveness and generalisability of these approaches require further evaluation across diverse TFM settings. 

What is already known on this topic

Traditional food markets are essential to food access and livelihoods in many low- and middle-income countries, but the trade of live animals and products of animal origin can create human–animal–environment interfaces where zoonotic and foodborne pathogens circulate. Existing evidence remains fragmented and is largely concentrated on avian influenza in poultry markets.

What this study adds

This scoping review maps 87 studies and uses a One Health framework to integrate evidence on public health risks, exposure pathways, human health outcomes and control-measure implementation in traditional food markets. It shows that risk is produced by interacting market infrastructure, hygiene, biosecurity, animal management and human practices, rather than by live animals or animal-origin products alone.

How this study might affect research, practice or policy

The findings suggest potential value in adaptive, context-specific One Health approaches rather than isolated technical controls. Policy and research should evaluate combinations of infrastructure, water, sanitation and hygiene, biosecurity, surveillance, vendor engagement, market regulation and livelihood-sensitive incentives, while expanding evaluation beyond avian influenza virus-focused poultry systems.  

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Preprint: Human Infection with Avian Influenza A(H7N7) Virus, Taiwan, 2026

 

#19,370

Last April 2nd, in Taiwan CDC: Human Infection with a Novel H7 Avian Virus, we looked at a lengthy report on Taiwan's first detection of a locally acquired human H7 LPAI infection in a poultry farmer.

The patient (a man reportedly in his 70s) was hospitalized with fever on March 22nd and subsequently developed pneumonia. He remained hospitalized and in isolation in early April, although his condition was said to be improving. 

The CDC also reported:

Currently, 33 close contacts are under health monitoring and management, and 3 have been given preventative medication based on risk assessment. Tests were conducted on 6 family members, all of whom tested negative.

The following day, we saw another Taiwan CDC Update: Novel H7 Infection Identified as H7N7.  We also saw a letter to physicians posted on April 8th.  At that time only the HA (H7) has been identified, with additional tests still pending.

We looked at a follow-up statement in early May (see Taiwan CDC: Statement/Update On Locally Acquired H7N7 Infection) after additional testing revealed the virus's PB2 gene carried the E627K mutation (PB2 E627K).

PB2-627K - which can often develop after a human/mammal is infected - is associated with enhanced replication and pathogenicity in mammals (see A rapid review of the avian influenza PB2 E627K mutation in human infection studies).

Yesterday an unusually terse (the abstract run just 50 words) preprint was posted on the medRxiv server which fills in some of the gaps on this event. 

We learn that virus (A/Taiwan/1/2026) was a low-pathogenic H7N7 bird flu virus from the wild-bird gene pool of Eurasia. The authors wrote:

Although the HA and M genes clustered with an A/environment/Kagoshima/KU-24-D10/2024(H7N7)-like virus isolated in Japan, the other gene segments were most closely related to different source viruses. Across the genome, 138A/Taiwan/1/2026 is distantly related to previously detected viruses from Taiwan and to reported human H7 viruses from China, Europe, and North America. 

The authors stated this suggests a recent spillover from a wild bird gene pool, as the virus is distinct from earlier H7N7 poultry viruses which have spilled over into humans. 

While it carried the PB2 E627K mammalian-adaptation marker, the authors cannot say whether that mutation was present in the bird host or arose post-infection in the patient (although the latter is suspected). 

Although no avian influenza virus was reported to have been detected in the duck farms visited by the patient, the authors suggest:

Based on the patient's occupation background, domestic ducks at the workplace may have served as an intermediate source of infection after introduction of the virus into Taiwan by migratory birds. However, direct exposure to migratory birds or their feces could not be excluded. 

None of the contacts tested showed serological evidence of infection. 

Follow the link to read the preprint in its entirety.  I'll return after the break with a postscript.

Human Infection with Avian Influenza A(H7N7) Virus, Taiwan, 2026

Yao-Tsun Li, Yun-Tong Lin, Bao-Shan Chen, Chuan-Yi Kuo, Hsiang-Yi Huang, Hui-Ying Ko, Pei-Yu Huang, Gavin JD Smith, Yi-Ling Lin, Ming-Tsan Liu
doi: https://doi.org/10.64898/2026.10.09.26365013
This article is a preprint and has not been certified by peer review [what does this mean?].  
 

Preview PDF

Abstract

Low pathogenic avian influenza A(H7N7) virus detected in a poultry worker in Taiwan, 2026 was related to viruses circulating in Asian wild birds and possessed PB2 E627K, a mammalian adaptation marker. Enhanced surveillance for H7 viruses in poultry and rapid characterization of human cases are essential to assess pandemic potential.

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While H5Nx gets most of our attention these days, H7 viruses have a fairly impressive track record of their own.

• In 2003, the Netherlands saw an outbreak of H7N7 that resulted in the loss of 30 million birds across 1,000 farms, and saw scores of mild human infections and the death of a veterinarian (see Eurosurveillance Human-to-human transmission of avian influenza A/H7N7, The Netherlands, 2003).

• Another analysis, performed by the RIVM (Ministry of Health) found the spread of the virus to be much greater than originally reported, citing as many as 1,000 human infections (see Executive summary Avian Flu Epidemic 2003: Public health consequences).

• Smaller H7 outbreaks, including the 2004 H7N3 outbreak in British Columbia, a small number of human infections in Wales in 2007, and 3 mild cases in Italy in 2013 (see ECDC : Human Infection By Avian H7N7 In Italy) were also reported.

• But the 5-year epidemic of H7N9 in China (2013-2018) - which hospitalized more than 1,500 people, killing roughly 40% of them - demonstrate just how formidable an H7 virus can be.

NYC's 2016 dramatic H7N2 outbreak in hundreds of cats, and spillover into animal shelter workers (see J Infect Dis: Serological Evidence Of H7N2 Infection Among Animal Shelter Workers, NYC 2016) - and a 2018 report of a severe H7N4 infection out of China - further illustrate the risks.

Of the 27 novel influenza viruses ranked by the CDC using their IRAT tool, H7 viruses make up 2 of the top 5 (in terms of emergence), and rank higher (in terms of impact) than any of the H5Nx viruses listed. 

Which is why we continue to follow these cases with considerable interest. 

Reminder: The Great Shakeout is set for This Week (Oct 15th)

 

#19,369

Not quite 3 years ago the USGS unveiled a new seismic risk map (see below), increasing the percentage of Americans at risk of experiencing a damaging earthquake to nearly 75% (roughly 240 million people).

Globally, large swaths of southern and central Europe and Asia - and significant portions of South America, Africa, Oceania and Canada - are at risk as well.

GEM_Global-Seismic-Hazard   DOI 10.5281/zenodo.20208536 (CC BY-NC-SA 4.0)

Publication:

Pagani M, Garcia-Pelaez J, Gee R, et al. (2020) The 2018 version of the Global Earthquake Model: Hazard component, Earthquake Spectra, vol. 36, no. 1_suppl, 2020, pp. 226–251. https://journals.sagepub.com/doi/abs/10.1177/8755293020931866

Data:

Johnson, K., Bayliss, K., Villani, M., Brooks, C., Styron, R., Simionato, M., Chen, Y., Rood, A., & Pagani, M. (2026). Global Earthquake Model (GEM) Seismic Hazard Map (v2026.1). [Data set] Zenodo. https://doi.org/10.5281/ zenodo.8409646

While yearly totals fluctuate, on average the USGS expects approximately 16 earthquakes of magnitude 7.0 -7.9 per year - and one of magnitude 8.0 or greater.

Over the past 4 months we've seen 7 Magnitude 7.0+ quakes, but that came after a nearly 2 month lull. Despite the internet clickbait hype machine, we are still well within expected norms.

But the fact remains, billions of people around the world live in active seismic zones, and knowing what to do during - and after - an earthquake can be lifesaving information. 

Eighteen years ago (Nov 2008) Shakeout.org held the first their first event - dubbed The Great Southern California ShakeOut - which involved over five million participants across the region. 

Since then, that event has grown - first nationally - and then internationally, and now it encompasses numerous states, territories, and a number of other countries.

This year's International ShakeOut Day is October 15, when millions of people worldwide will participate in earthquake drills at work, school, or home!

At 10:15 a.m. (local time) on 10/15, you can join millions of people across the world practicing earthquake safety.

While we encourage participation with everyone, you can register your ShakeOut drill for any day of the year, and drill at a time of your choice. You can also include people in multiple locations through video conferencing.

While I don't have to worry much about earthquakes where I live (I make up for it with hurricanes. sinkholes, and alligators), I put high value in being prepared for all natural disasters, and I strongly urge others to do so as well.

If you live in, work in, or ever plan to visit a seismically active area, I strongly would urge you, your family, and your employees take part in these yearly drills.

Once the shaking stops, you'll have to find ways to cope with the aftermath.

While the government will send help, you could find yourself pretty much on your own for several days and living in less than comfortable conditions for weeks (see #NatlPrep: 75% of Americans At Risk Of Experiencing A Damaging Earthquake).

For starters - and as a bare minimum - every household should have a disaster plan, a good first aid kit (and the knowledge to use it), an emergency battery operated NWS weather radio, and emergency supplies to last at least 72 hours during a disaster.

While 72 hours is an admirable start, I wouldn't feel comfortable stopping there. Here in the United States many agencies and organizations recommend that households work towards having a 10-to-14 day supply of food, water, and emergency supplies on hand.

In addition to earthquakes, there are nearly a dozen `very high risk' volcanoes in the continental US (4 in Washington, 4 in Oregon & 3 in California), along dozens of `lesser' threats. While earthquake damage is generally localized, volcanic eruptions can affect property and populations thousands of miles away.

Over the years we've looked at a number of scientific or review articles on earthquake risks, including: 

(JGR) Cajon Pass and the Southern San Andreas Fault System: Earthquake Cycle Stress Accumulation and Present-Day Loading

Dr. Lucy Jones: `Imagine America Without Los Angeles’
California Quakes : Concrete Concerns

OSU: Pragmatic Action - Not Fatalism - In Order To Survive The `Big One’

Estimating The Economic Impact Of A San Andreas Quake

WHO DON : Pneumonia of undetermined etiology - Russian Federation

 

#19,368

For the past week we've been following unverified media reports (see here, here, and here) of a Russian lab leak - supposedly of plague - (vigorously denied by Rospotrebnadzor) after the death of a lab worker from severe pneumonia in early October. 

Despite the Russian denials and reassurances, we really don't know exactly what happened - or may still be happening - at that Siberian lab.  

Today the WHO published a lengthy DON (Disease Outbreak News) report on the incident. While it provides several new details from the Russians, this report continues to stress that there are still a number of unknowns.

The WHO now offers a limited-confidence risk assessment, but it is tempered  by the lack of a confirmed diagnosis in the deceased laboratory worker, and ongoing uncertainty over the `source and mode of exposure'.

Due to its length, I've only posted the link, and a few excerpts.  Follow the link to read the DON in its entirety. 

Pneumonia of undetermined etiology - Russian Federation
10 October 2026

Situation at a glance

On 2 October 2026, WHO became aware through media reports of the death of an employee of the Irkutsk Antiplague Research Institute (APRI) of Siberia and the Far East, the Russian Federation. According to these reports, the individual died on 2 October following hospitalization for severe pneumonia on 29 September, and pneumonic plague was suspected as the cause of death, following occupational exposure in laboratory settings. 

Following requests for verification from WHO, the National Focal Point for the International Health Regulations (2005) (NFP) of the Russian Federation confirmed the death and informed WHO that no case of plague had been registered recently in Irkutsk Oblast, that preventive and control measures had been implemented in accordance with national sanitary legislation, and that the laboratory testing of contacts detected no high-threat pathogens. 

The authorities also reported that no biosecurity incidents had occurred in the laboratory, contrary to reports in the media, and that there were no further case of severe pneumonia linked to this case. The NFP informed WHO that the case and all contacts had been tested for a range of microorganisms, including high-threat pathogens. Test results were negative for the tested high-threat pathogens. All contacts had been medically followed up in healthcare facilities or at home, and all remained asymptomatic throughout. Quarantine measures were instituted in the hospital where the patient was being treated. 

Based on the information provided by NFP, WHO has not identified evidence of ongoing transmission associated with this event. A key uncertainty remains the absence of a confirmed diagnosis in the deceased laboratory worker. WHO will continue to monitor the situation and assess any potential public health implications as further information becomes available.

        (SNIP)

WHO risk assessment

WHO’s rapid risk assessment is a systematic and continuous process that characterizes the risk posed by a public health event and informs measures to reduce its impact and prevent international spread.

A key uncertainty for this event is the absence of a confirmed diagnosis in the deceased laboratory worker. According to information provided by the national authorities, testing did not identify plague or other tested high-threat pathogens, and the death has been classified as pneumonia of undetermined etiology. However, WHO has not received information identifying the causative agent responsible for the fatal illness. Given the absence of a confirmed diagnosis, WHO is not in a position to independently assess whether the duration of the reported monitoring period for contacts was sufficient to exclude all plausible causes of the fatal illness.

The occupational setting of the case remains an important consideration. The deceased individual worked at an institution that handles high-consequence pathogens, and precautionary public health measures were reportedly implemented because of the individual's professional activities. While the information provided by the authorities does not indicate infection with tested high-threat pathogens or identify additional linked cases, the source of the fatal illness remains undetermined. A laboratory-associated exposure therefore cannot be fully excluded at this stage.

Based on the information provided by NFP, WHO has not identified evidence of ongoing transmission associated with this event.

However, confidence in the assessment remains limited by the absence of a confirmed etiological diagnosis, and the remaining uncertainty regarding the source and mode of exposure. Additional clinical, epidemiological and laboratory information, including confirmation of the diagnosis in the deceased laboratory worker, is required to improve confidence in the assessment. WHO will continue monitoring the situation and assess any potential public health implications as further information becomes available. 

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ISRV: Nomenclature Updates to the Hemagglutinin Gene Clade Designations Resulting From the Continued Evolution of High Pathogenicity Avian Influenza A(H5) Virus Clades 2.3.2.1c and 2.3.4.4

(Credit CDC)

#19,367

Thirteen years ago in 2013's EID Journal: The Expanding Variants Of H5N1, we looked at the continued evolution and diversification of H5N1 viruses around the globe.  At that time I wrote:

H5N1 virus was first identified in 1996 it has expanded into more than 20 different clades and subclades, and various versions of the virus now circulate in different parts of the world. You can see the evolution of the virus through 2011 in the chart below. 

NOTE: Not all of these clades continue to circulate.

 Clade 2.3.2 (and now 2.3.2.1) are very common in South East Asia, clades 2.2.1 and 2.2 are endemic in Egypt and clades 2.1.1, 2.1.2. and 2.1.3 are found in Indonesia.

This snapshot was taken before the emergence, and eventual world domination, of H5N8  clade 2.3.4.4, which would begin decimating South Korean poultry just two months after this was published, and of an H5N6 clade 2.3.4.4a virus which emerged in Sichuan, China a few months after that. 

In many ways, 2014 was a pivotal year for H5Nx viruses, with H5N1's dominance soon to be supplanted by a less deadly (to humans), but more easily spread by migratory birds, H5N8 clade 2.3.4.4x lineage.  

Older clades, such as Cambodia's 2.3.2.1c H5N1 virus went to ground (but would return roughly a decade later).  H5N8 dominated until 2020-2021, when an H5N1 clade 2.3.4.4b came roaring back, largely supplanting H5N8. 

In the spring of 2025, Cambodia's clade 2.3.2.1c was provisionally redesignated clade 2.3.2.1e  after analysis showed it had drifted away from the older clade. 

Similar evolutionary shifts have been happening in other clades over the past dozen years, which is why the WHO/WOAH/FAO H5 Evolution Working Group has updated the naming system for H5 bird flu viruses for the first time since their 2014 update.

Today's report from Influenza and Other Respiratory Viruses updates the official nomenclature for H5 viruses up to July 4, 2024.  

The working group added 12 new subclade designations:

• Clade 2.3.2.1c was split into 2.3.2.1c–g. 
• 2.3.2.1d: China, 2014–2016.
• 2.3.2.1e: Vietnam and Cambodia, 2020–2024. 
• 2.3.2.1f: India, the Middle East and Africa.
• 2.3.2.1g: Indonesia, 2012–2016.

• Clade 2.3.4.4 was split into 2.3.4.4a–h 
• plus a "2.3.4.4-like" label for 125 outlier viruses that don't fit neatly

Some of these designations have been used provisionally for years, but are now made official. 

Although there was enough divergence among clade 2.3.4.4b viruses to technically warrant additional subclade splits, that decision has been deferred for now:  The Authors explained:

Furthermore, several of the newly designated 2.3.4.4 subclades had intra-clade APDs over the 1.5% threshold required for further splitting of clades due to the rapid expansion of these clades into new regions (e.g., 1.98% intra-clade APD of 2.3.4.4b representing over 13,000 sequences). Due to sampling biases stemming from the overrepresentation of sequences from specific outbreaks and insufficient data from regions with recent introductions, further subdivision of subclades with intra-clade APDs greater than 1.5% was deferred. Additional genetic data are needed to better assess the endemicity of specific clusters and justify further splits beyond the current subclades 2.3.4.4a–h.

Due to the highly technical and niche nature of today's study, I've only posted the link and abstract. Those wanting a deeper dive will want to follow the link to read it in its entirety. 

I'll have a brief postscript after the break.

Nomenclature Updates to the Hemagglutinin Gene Clade Designations Resulting From the Continued Evolution of High Pathogenicity Avian Influenza A(H5) Virus Clades 2.3.2.1c and 2.3.4.4

Tommy T. Lam, C. Todd Davis … See all authors 

First published: 07 October 2026 https://doi.org/10.1111/irv.70317

Group members and collaborators are provided in the Supporting Information (Data S1). 

 

ABSTRACT

Background and Methods

The evolutionary divergence of the A(H5) hemagglutinin (HA) gene of high pathogenicity avian influenza (HPAI) viruses (A/goose/Guangdong/96 lineage) was analyzed by phylogenetic and average pairwise distance methods to identify clades that merit nomenclature updates.

Results and Conclusions

Based on this assessment, 12 new clade designations were recommended based on division of clade 2.3.2.1c and 2.3.4.4 viruses, which were reported in Africa, Antarctica, Asia, Europe, the Middle East, the Americas, and Oceania since the most recent WHO/WOAH/FAO H5 Evolution Working Group update.

        (Continue . . . )

H5's evolution continues, and we will undoubtedly see additional `provisional' clade and subclade designations added in the years ahead.  

The bottom line is that H5 viruses have not only grown more diverse, they are a far cry from what emerged in China in the 1990s, and sparked pandemic fears in the early 2000s. 

Whether any of that gives them the ability to spark a human pandemic remains to be seen.  But it would be reckless to assume that since their ancestors didn't, their descendants never will.  

Isaias Forecast To Become A Major Hurricane Later Today - Landfall Tonight

 

#19,366

While wind shear may lower its intensity a bit (depending on timing) as it approaches the coast, Isaias is expected to be at least a strong CAT 2 storm at landfall, possibly higher.  

Regardless of its intensity, Isaias is expected to produce life-threatening surge, high winds, and torrential rains.  Residents in the affected area should hurry to complete the preparations today. 

While most people prepare for the actual storm, often the days (and sometimes weeks) following the storm are the most stressful.  

The power may be out for days, floodwaters may contain hidden dangers, local stores may be closed, and people may risk injury using chainsaws, generators, or ladders. 

I've written extensively on After The Storm Passes, but many of those preparedness links are no longer active. The CDC has updated their Preparing for Hurricanes or Other Tropical Storms webpage, covering most of those topics. 

A few related blogs you may wish to revisit include:

• Carbon Monoxide Poisoning (see CDC HAN 00415: Hurricane Florence — Clinical Guidance For Carbon Monoxide (CO) Poisoning)
• Chain saw accidents (see Preventing Chain Saw Injuries During Tree Removal After a Disaster)
• And even psychological impacts (including PTSD) (see Sandy 1 Year Later: Coping With The Aftermath).