ECDC Ebola Threat Assessment Brief

 

#19,173

While it is still early days - and data remains sparse - the ECDC has produced a preliminary threat assessment for EU nations from the growing Ebola Bundibugyo outbreak in the DRC and Uganda.

Due to its length (n=9 pages), I've only reproduced the summary. Follow the link to read it in its entirety. 

Ebola disease outbreak caused by Bundibugyo virus – Democratic Republic of the Congo and Uganda – 202621 May 2026

Summary

On 15 May 2026, Africa CDC reported an outbreak of Ebola disease in Ituri Province, DRC. Laboratory analysis at Institut National de Recherche Biomedicale of DRC identified Bundibugyo virus (BDBV). BDBV disease is a rare disease but can cause outbreaks with high case fatality rates. Considering the available information,complicated context and the uncertainties on the epidemiological information WHO declared a Public Health Emergency of International Concern on 17 May 2026. Africa CDC declared a Public Health Emergency of Continental Security on 18 May 2026.

This Threat Assessment Brief aims to assess the risk for people from the EU/EEA living in or travelling to affected areas and the overall risk of BDBV for the general population in the EU/EEA in the context of the ongoing outbreak of BDBV disease in DRC. It is intended for public health authorities in EU/EEA countries and is based on currently available evidence. It therefore carries considerable uncertainty.

Recommendations are also included for how public health authorities in the EU/EEA can strengthen preparedness and response capabilities. 

Epidemiological situation 

Based on data reported by the World Health Organisation as at 20 May 2026, almost 600 suspected cases and 139 deaths among the suspected cases have been reported. In DRC, 51 cases were confirmed in Ituri and North Kivu Provinces. While two imported cases were confirmed in Kampala, Uganda. At least five deaths had been reported among the confirmed cases as at 18 May, four in DRC and one in Uganda. Due to the very recentdeclaration of the outbreak and the uncertainties related to the epidemiological information, it is probable that theout break is larger than what is currently being reported, not only regarding the number of affected cases but also to its geographical extent. BDBV transmission requires direct contact with blood, or other bodily fluids of living or deceased infected people, or any surfaces and materials soiled by infectious fluids. Transmission can also occur through contact with dead or live infected animals, including handling and/or consuming bushmeat, or by visiting caves or mines colonised by bats. There are currently no licensed vaccines or specific treatments available for BDBV disease.

Risk assessment 

Although epidemiological information remains limited and there are important uncertainties, the likelihood of infection for people from the EU/EEA living in or travelling to affected areas is assessed as low, provided they adhere to the recommended precautionary measures. Transmission requires direct contact with blood, secretions,organs, or other bodily fluids of dead or living infected people or animals; all unlikely exposures for the general EU/EEA travellers or expatriates in affected areas.

Staff members of humanitarian, religious and other organisations, particularly healthcare workers who are in direct contact with patients and/or local communities in the affected areas, are more likely to be exposed to the virus. Provided they adhere to the appropriate infection prevention and control measures, the likelihood of infection for this group is also low.

The most likely route by which the virus could be introduced to the EU/EEA is through people with a BDBV infection travelling from affected areas to the EU/EEA. During the Ebola disease outbreak in West Africa in 2013– 2016, which was the largest outbreak to date, where tens of thousands of cases were reported, with transmission in large urban centres, and hundreds of EU/EEA humanitarian and military personnel deployed to the affected areas, only a small number of imported cases to Europe were reported, most of them medically evacuated for treatment.

Based on this experience, it is expected that imported cases would be a rare event. The likelihood of secondary transmission of BDBV within the EU/EEA and the occurrence of sustained chains of transmission within the EU/EEA is considered very low, as cases are likely to be promptly identified and isolated and recommended control measures would be implemented. Although BDBV infection can cause severe disease in affected individuals, the population-level public health impact in the EU/EEA is expected to be very low because only very few cases would occur. Therefore, the overall current risk of BDBV for the general population in the EU/EEA is assessed to be very low.

Recommendations

EU/EEA countries should review and update the standard operating procedures on isolation and treatment for BDBV disease cases, and on contact tracing and quarantine for contacts of cases as needed.

EU/EEA public health authorities should:

1. Increase awareness among travellers to, and residents of affected areas, as well as returning travellers;

2. Increase awareness among health professionals on:

(i) the possibility of BDBV disease in travellers returning from affected areas;

(ii) the clinical presentation of the disease and the need to ask about the travel history and contacts of people returning from affected areas;

(iii) the availability of protocols for testing suspected cases;

(iv) infection prevention and control (IPC) procedures and appropriate management of suspected or confirmed cases.

3. Strengthen readiness to rapidly detect imported cases, promptly isolate them, and implement appropriate infection prevention and control measures.

4. Review testing capacity and BDBV diagnostic procedures. The EU reference laboratory for public health on Emerging, rodent-borne and zoonotic viral pathogens (EURL-PH-ERZV) offers diagnostic services to EU/EEA countries lacking capability to diagnose BDBV infection.

5. Minimise exposure in healthcare settings requires appropriate procedures, trained staff, and equipment for the safe management of BDBV cases.

6. Provide all returning travellers with clear information on symptoms, route of transmission, and what todo if symptoms develop after arrival in the EU/EEA: travellers who develop symptoms compatible with BDBV infection within 21 days after return should self-isolate, seek medical care promptly, and report their travel history and possible exposures. 

Exit screening in affected countries, including symptom checks and exposure assessment, is crucial as it contributes to risk reduction by identifying symptomatic travellers before boarding and preventing travel while symptomatic. Exit screening also helps dissuade ill people from travelling and enhance public and stakeholder confidence. However, it cannot fully prevent exportation of cases, because absence of symptoms at departure does not exclude subsequent onset of disease.

ECDC actions

ECDC is monitoring the outbreak through its epidemic intelligence activities to provide epidemiological updates,situational awareness and assess the risk for the EU/EEA.

ECDC has deployed an expert through the EU Health Task Force to the Africa Centres for Disease Control and Prevention (Africa CDC) headquarters in Addis Ababa to support coordination and operational planning.

ECDC is in discussions with the European Civil Protection and Humanitarian Aid Operations (ECHO) and the Global Outbreak Alert and Response Network (GOARN) regarding the deployment of additional experts to support response activities in DRC and Uganda.

The European Union Reference Laboratory for public health on emerging, rodent-borne and zoonotic viral pathogens (EURL-PH-ERZV) offers support to the EU/EEA national reference laboratories for the diagnosis of BDBV infection, biosafety advice for handling and inactivation of samples, and also offers diagnostic services to EU/EEA countries for BDBV infection.

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Eurosurveillance: Cross-reactive human antibody responses to H9N2 influenza virus, New York, United States, 2025

Credit NIAID

 

#19,172

While LPAI H9N2 remains far from our biggest pandemic concern, the CDC has designated 2 different lineages (A(H9N2) G1 and A(H9N2) Y280) as having at least some pandemic potential (see CDC IRAT SCORE), and several candidate vaccines have been developed.

Many will be surprised to find that, in terms of risk of emergence, the H9N2 Y280 lineage is ranked higher than H5N1, while the G1 lineage is ranked only slightly lower.

Although our concerns are primarily with the Asian lineages of H9N2, only a week ago in Preprint: Outbreak of H9N2 Avian Influenza Viruses in Lesser Rhea in Peru, June-July 2025 we looked at the unexpected emergence of a South American lineage. 

H9N2 viruses are infamously promiscuous, and are constantly reassorting with other subtypes, which only increases their pandemic potential (see PNAS: Evolution Of H9N2 And It’s Effect On The Genesis Of H7N9).

All of which makes it important to know how much existing immunity their might be in the community should LPAI H9N2 ever embark on a world tour; particularly from regions of the world where the virus has not been circulating. 

To that end we have the following Rapid Communication - published yesterday in the journal Eurosurveillance - which looks at a relatively small cohort (n=298) of serum samples collected in NYC between between Feb 2024 and Apr 2025, which they tested for signs of pre-existing immunity against 1 specific strain (A/Changsha/SR353/2025 - Y280 lineage) of LPAI H9N2. 

In brief, they found widespread - but weak - cross-reactive haemagglutinin (HA)-binding antibodies among the 298 samples, likely due to previous seasonal flu vaccinations and/or exposures (see comparison chart below).

On the other hand, neuraminidase-inhibiting antibodies were more common and stronger.  All this suggests that while protection against H9 infection is likely very limited - and unlikely to create much of a barrier for the spread of the virus - the stronger NA antibodies may help reduce the severity of infection. 

At least that's the hope.

Interestingly, there is a small but perceptible dip in both HA and NA inhibition activity in those born in the mid-to-late 1980s and early 1990s, but given the small sample size and weak response, this may not be significant.  

Although the news isn't all bad, this study looks at only one small and geographically limited dataset - and one specific strain of LPAI H9N2 - so there is only so much we can infer from their findings. 

I've only posted the link and some excerpts below, most will want to follow the link to read the report in its entirety. 

Open Access
Cross-reactive human antibody responses to H9N2 influenza virus, New York, United States, 2025 

Gagandeep Singh1,2 , Disha Bhavsar1,2 , Lucas M Ferreri3 , Jessica R Nardulli1,2 , Charles Gleason1,2 , Neko Lyttle1,2 , Yuexing Chen1,2 , Anice C Lowen3 , Viviana Simon1,2,4,5,6 , Florian Krammer1,2,6,7,8  

Avian influenza A(H9N2) viruses have been endemic in poultry for many years across Asia, the Middle East, and Northern and Western Africa and have been detected periodically in the Americas and Europe. Since their first detection in 1966, H9N2 viruses have evolved into multiple lineages and exhibit a high propensity for reassortment, contributing internal genes to zoonotic viruses such as H5N1, H7N9 and H10N8 [1,2].

Human infections with H9N2 viruses have been reported since 1998, with most cases linked to poultry exposure and typically resulting in mild or asymptomatic disease but severe cases and deaths have been observed as well. Despite these observations, population-level immunity to H9N2 remains poorly defined, particularly in regions without endemic exposure to the virus.

Here, we assessed cross-reactive antibody responses to H9N2 viruses using a panel of recently collected human sera from the general population of a large metropolitan city in North America (New York City)

        (SNIP)

Our work describes pre-existing immunity at population level to avian influenza A(H9N2) viruses in adults from New York City. We observed widespread cross-reactive haemagglutinin (HA)-binding antibodies in the sampled group; however, these responses were of lower magnitude than those against seasonal H3. Consistent with this, HI and neutralising antibody responses to H9N2 were low or undetectable in most individuals, indicating limited functional immunity.

In contrast, a high proportion of individuals exhibited N2-binding and NI antibodies, including cross-reactive responses to H9N2. Although NA-directed antibodies do not prevent infection, they may reduce viral replication and disease severity, potentially providing the population with some degree of resilience against emerging influenza viruses [6,7]. The comparable magnitude of NI responses to H9N2 and H3N2 suggests that prior exposure to seasonal influenza viruses has generated cross-reactive NA immunity. This is consistent with historical observations that pre-existing anti-N2 antibodies, induced during circulation of A(H2N2) viruses, may have contributed to reduced disease severity during the emergence of the A(H3N2) pandemic [17,18].

The difference between HA and NA responses is not surprising. Comparative sequence analysis revealed substantial divergence between the HA proteins of lineage B4.7.2 virus A/Changsha/SR353/2025 (H9N2) and seasonal A/Thailand/8/2022 (H3N2), with only approximately 40% amino acid identity. In contrast, the N2 neuraminidases of the two viruses showed high conservation, sharing approximately 89% amino-acid identity.

Our study also has several limitations. Vaccination data were not captured, and we therefore cannot draw any conclusions about the effect of seasonal vaccination on H9N2 immunity. Furthermore, our analysis was restricted to a small, geographically limited group of individuals. Finally, different lineages of H9N2 circulate and they are antigenically distinct. This study only used one of these viruses as reagent and cross-reactive responses to other lineages of H9N2 may differ.

Conclusion

In summary, we found that pre-existing immunity to H9N2 in humans that is dominated by cross-reactive but largely non-neutralising antibodies, with a greater contribution from NA-directed responses. Given the pandemic potential of H9N2 viruses, these findings have important implications for risk assessment and support the inclusion of NA immunity in vaccine development strategies.

Further studies are needed to confirm whether cross-reactive NI antibodies confer protection against H9N2 infection or modulate disease severity, but our results suggest that the antibodies against H9N2 virus might derive from exposure to conserved epitopes shared between the avian-origin and seasonal strains.

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CDC: Enhanced Ebola Airport Screening Begins at Washington-Dulles International Airport

 

#19,171

As we discussed 3 days ago in CDC Statement on the Use of Public Health Travel Restrictions to Prevent the Introduction of Ebola Disease into the United States, we possess no technology that permits us to reliably screen presymptomatic travelers entering the United States for infectious diseases. 

Temperature screening and health questionnaires can help identify some infected individuals - but with incubation periods that can range from days to weeks - only a small percentage of cases will likely be detected.

There are obvious advantages to identifying (and isolating) those already showing signs of illness, as they are most likely to be infectious. But once a virus becomes sufficiently transmissible among humans, the best we can hope for is to slow the spread (see Why Airport Screening Can’t Stop MERS, Ebola or Avian Flu).

Different diseases spread at different rates, and luckily Ebola (like Hantavirus) requires far closer, and more prolonged, contact than highly contagious pathogens like measles or influenza.

That doesn't render them incapable of international spread, but neither have shown the ability to spread like a classic pandemic virus (with the caveat that viral evolution means that whatever we say today may not necessarily hold true tomorrow).  

Yesterday the CDC announced plans to redirect returning American travelers who have recently (within 21 days) visited the DRC, Uganda, or South Sudan to Washington Dulles International Airport, where they will be screened for potential Ebola exposure. 

Those who are asymptomatic will be provided health information - and told what to do if symptoms should later appear - then allowed to proceed to their final destinations.  Those who are symptomatic will be evaluated by a CDC health officer.   

Should conditions warrant, there is always the option of adjusting these screening protocols. 

The CDC's full statement follows:

Enhanced Ebola Airport Screening Begins at Washington-Dulles International Airport

Statement
For immediate release: May 21, 2026
CDC Media Relations
(404) 639-3286

On May 18, 2026, the CDC issued an Order suspending entry to the United States of foreign nationals who were in the Democratic Republic of Congo (DRC), Uganda, or South Sudan within 21 days before arrival. U.S. citizens, U.S. nationals, and lawful permanent residents who were in these countries within 21 days are permitted to enter the United States.

The Department of Homeland Security (DHS) posted a Federal Register notice, available here, that outlines the redirection of these affected travelers to Washington-Dulles International Airport (IAD) beginning 11:59 p.m. May 20, 2026, for enhanced public health screening.

CDC will conduct the enhanced public health entry screenings for these travelers and confirm their contact information for public health follow-up if recommended. Travelers that have been in the DRC, Uganda, and South Sudan in the 21 days before their flight, and are scheduled to travel to the United States, while screening is taking place will be contacted by their airline to rebook travel to IAD.

To date, no suspected, probable, or confirmed cases of Ebola have been reported in the United States, and the risk of Ebola domestically is low. However, public health entry screening is part of a layered approach that, when used with other public health measures already in place to detect symptomatic arriving travelers, can slow and reduce the spread of disease into the United States.

How Public Health Entry Screening Works

• Travelers who were in DRC, Uganda, or South Sudan in the 21 days before arriving to the United States will be escorted to an area of the airport set aside for screening.
• Travelers will respond to a brief questionnaire that asks about their travel history and symptoms, and collects information so the travelers can be contacted, if needed.
• CDC staff will observe these travelers for signs of illness and take travelers' temperatures using non-contact thermometers (thermometers that do not touch the skin).
• Travelers who do not have symptoms, but have been in DRC, Uganda, or South Sudan in the past 21 days will be given information on monitoring their health and actions to take if symptoms later appear. These travelers will continue to their final destinations. Traveler contact information will be shared with state and local health departments for additional follow-up and support.
• If a traveler has a fever or other symptoms, the traveler will be evaluated by a CDC public health officer.
• CDC partners with state and local public health authorities and designated hospitals within those states to work quickly to identify and take appropriate public health actions for persons who present with symptoms of illness in the community. Working together, U.S. federal, state, and local authorities are ready to manage travelers who become ill after they reach their destinations.
• If a suspect case is identified, CDC will work with state/local health departments to conduct routine contact investigations to notify passengers.

CDC is prepared to provide additional resources in response to this Ebola outbreak in DRC and Uganda. The latest information on this outbreak is available here.

NOAA Predicts Below-Normal 2026 Atlantic Hurricane Season

 

CLIMATE PREDICTION CENTER/NCEP/NWS: El Niño is likely to emerge soon (82% chance in May-July 2026) and continue through Northern Hemisphere winter 2026-27 (96% chance in December 2026-February 2027).

#19,170

While there are a great many potentially negative impacts to global weather from the forecasted (moderate-to-strong) El Niño, the one bright spot for those of us who live along the Atlantic and Gulf coasts is its tendency to dampen the intensity of the Atlantic Basin Hurricane season. 

Hurricanes will undoubtedly still appear, but during El Niño conditions, they tend to be less frequent.  And after the battering the Gulf States have taken over the past decade, any respite is a welcome one. 

Today, NOAA released their 2026 Atlantic Hurricane outlook which predicts a below-normal season ahead.  The caveat being, that one of the worst storms in decades - 1992's Cat 5 Hurricane Andrew - struck during a relatively quiet  El Niño year. 

As they say, it only takes one. Which is why I'll prep this year with the same intensity as I do every year (see past blogs here, here, here, and here).  

Some excerpts from today's announcement from NOAA:

NOAA predicts below-normal 2026 Atlantic hurricane season

Early preparation essential to staying safe all season

May 21, 2026


A NOAA satellite view of a massive Hurricane Erin churning off the U.S. East Coast taken August 20, 2025. (Image credit: NOAA Satellites)
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RESOURCES

NOAA Research: New technology, advanced models and AI deployed to improve hurricane forecasting

2026 Atlantic Hurricane Season Outlook - Spanish

2026 Atlantic hurricane names graphic - Spanish

Forecasters with NOAA’s National Weather Service are predicting a below-normal hurricane season for the Atlantic basin this year. NOAA’s outlook for the 2026 Atlantic hurricane season, which runs June 1 to November 30, predicts a 35% chance of a near-normal season, a 10% chance of an above-normal season, and a 55% chance of a below-normal season.

The agency is forecasting a total of 8-14 named storms (winds of 39 mph or higher). Of those, 3-6 are forecast to become hurricanes (winds of 74 mph or higher), including 1-3 major hurricanes (category 3, 4 or 5 with winds of 111 mph or higher). NOAA has a 70% confidence in these ranges. An average season has 14 named storms with seven hurricanes, including three major hurricanes.

“With the most advanced forecast modeling and hurricane tracking technologies, NOAA and the National Weather Service are prepared to deliver real-time storm forecasts and warnings,” said Commerce Secretary Howard Lutnick. “Our experts are integrating cutting-edge tools to ensure communities in the path of storms receive the earliest, most accurate information possible.”

“NOAA’s rapid integration of advanced technology, including AI-based weather models, drones, and next-generation satellite data will deliver actionable science to safeguard the lives and livelihoods of the American people,” said NOAA Administrator Neil Jacobs, Ph.D. “These new capabilities, combined with the unmatched expertise of our National Weather Service forecasters, will produce the most accurate forecasts possible to protect communities in harm’s way.”

(Continue . . . )

If this is your first hurricane season - or you would just like a refresher - you'll find a number of short videos on hurricane prepareded at this NOAA website:

Hurricane Prep: social media (English)

The Hurricane Preparedness Week Social Media Plan

2026 SOCIAL MEDIA PLANS AND VIDEOS English: May 3 - May 9, 2026

En español: 3 de mayo - 9 de mayo de 2026

Chinese: 年5月3日 - 2025年5月9日

Vietnamese: Ngày 3 Tháng 5, Năm - Ngày 9 Tháng 5, Năm 2026

English: Videos

En español: Videos

#HurricaneStrong #HurricanePrep

Please help the NWS spread the word about Hurricane Preparedness Week (May 3-May 9, 2026) on social media! Everyone is welcome to use the text and images provided below to help the NWS build a Weather-Ready Nation.

May 3, 2026 — Know Your Risk: Wind & Water

May 4, 2026 — Prepare Before Hurricane Season

May 5, 2026 — Understand Forecast Information

May 6, 2026 — Get Moving When a Storm Threatens

May 7, 2026 — Stay Protected During Storms

May 8, 2026 — Use Caution After Storms

May 9, 2026 —Take Action Today

And a reminder, you don't have to live on the coast to be impacted by a hurricane or tropical storm.  Often flooding, high winds, and even tornadoes are reported hundreds of miles inland, and days after landfall.  

While this blog, and many other internet sources (I follow Mark Sudduth's Hurricane Track, and Mike's Weather page), will cover this year's hurricane season. your primary source of forecast information should always be the National Hurricane Center in Miami, Florida.

These are the real experts, and the only ones you should rely on to track and forecast the storm.

If you are on Twitter, you should also follow @FEMA, @NHC_Atlantic, @NHC_Pacific and @ReadyGov and of course take direction from your local Emergency Management Office. 

MMWR: Knowledge, Attitudes, and Practices Regarding Avian Influenza Among Owners of Backyard Flocks

 

#19,169

Although numbers vary between published sources, since 2020 there has been a significant increase in the number of people who have decided to raise backyard poultry - especially hens for eggs - across the United States (see Chicken Coops Market Outlook 2025 to 2035).

The APPA estimates `Eleven (11) million U.S. households own backyard chickens (a 28% increase from 2023)'

 

Since late 2021, HPAI H5 avian influenza has become endemic in wild North American birds, and has affected both commercial and backyard poultry flocks in all 50 states (see graphic below).

 While the CDC has released biosafety guidelines (see Backyard Flock Owners: Protect Yourself from Bird Flu) - it is unknown how many backyard poultry owners have actually read it, or would be willing to follow their recommendations. 

And while H5Nx is our biggest concern, there are other avian subtypes which have been reported in North America with zoonotic potential, including several subtypes of H7. 

Over the past 18 months we've seen at least 3 U.S. backyard flock owners infected with HPAI H5, resulting in 2 deaths. This is an all-too familiar pattern, which we've seen repeated dozens of times in many other countries. 

Last year, after Hawaii's first detection of H5N1, their DOH conducted a survey of local residents aged 18 years or older who either kept birds at home, performed animal rescue, or engaged in other bird-related activities.  The results indicated more education was needed:

All of which brings us to a new survey, published last week in the CDC's MMWR, which looks at similar knowledge and practices among backyard poultry owners in the United States.  It is subject to some significant limitations, including:

• This survey used an online convenience sample of highly educated (47% held held graduate or professional degrees) respondents, which is far higher than the general population (and likely target group of backyard poultry owners). 

• And people often over-state their intentions in these types of surveys, much as we saw a dozen years ago (see BMJ: The `Hawthorne Effect’ On Hospital Hand Hygiene Compliance); where HCWs who knew they are being observed washed their hands far more often than when believed unobserved.

But, it's a starting point.  And even with these advantages, the survey turned up some important gaps in knowledge about avian flu. I've posted the summary, abstract, and some excerpts from the MMWR report below. 

Follow the link to read it in its entirety. I'll have a bit more after the break.

Knowledge, Attitudes, and Practices Regarding Avian Influenza Among Owners of Backyard Flocks — United States, July–December 2025

Weekly / May 14, 2026 / 75(18);234–239
Print

Melissa A. Rolfes, PhD1; Leah Bauck, MPH2; Beth A. Lipton, DVM3; Sara F. Margrey, DVM4; Rebecca A. Campagna, DVM5; Elizabeth Harker, MPH1; Colin A. Basler, DVM6; Courtney M. Dewart, PhD4,7; Sascha R. Ellington, PhD1; Stacy M. Holzbauer, DVM2,7; Malia J. Ireland, DVM2; Jeremy W. Kuo, MPH8; Christine M. Szablewski, DVM1; Lizette O. Durand, PhD, VMD1; Carrie Reed, DSc1 (VIEW AUTHOR AFFILIATIONS)View suggested citation

Summary

What is already known about this topic?

Since 2024, three human influenza A(H5) cases have been reported among people in the U.S. who own backyard birds. Although previous surveys suggest that backyard flock owners are aware of avian influenza, information on knowledge, attitudes, and practices is needed to guide development of education and prevention materials.

What is added by this report?

A survey of 638 U.S. backyard flock owners revealed incomplete knowledge about signs and symptoms of avian influenza in humans and birds. Respondents who knew more about avian influenza were more likely to report an intention to use personal protective equipment if they were to interact with potentially infected birds.

What are the implications for public health practice?

Education of backyard flock owners by health partners regarding signs and symptoms of avian influenza can help flock owners keep their flocks, themselves, and their families healthy.

Article PDF

Full Issue PDF

Abstract

Many U.S. households keep backyard bird flocks for their personal food supply or as garden partners. Backyard flocks in the United States have occasionally been infected with avian influenza A viruses, putting flock owners at risk for exposure. During July–December 2025, CDC, in collaboration with state health and agricultural partners, conducted an online survey to learn more about backyard flock owners and their knowledge, attitudes, and practices related to avian influenza.

Among 638 respondents who completed the survey, 92% were White (and not Hispanic or Latino), and approximately one half had a graduate or professional degree; a majority kept small, predominantly chicken flocks; and many reported that wild birds could access their flock or the flock’s food or water, which increases the flock’s risk for avian influenza exposure.

Although a majority of respondents had heard of avian influenza, approximately one third were unaware of the signs and symptoms of infection in their birds or humans. If they needed to interact with ill or dead birds, a majority of owners knew the recommended precautions to take and indicated willingness to use most, though not all, recommended personal protective equipment. These findings highlight important topics for risk messaging and educational resources so that backyard flock owners are better informed and better able to protect their flocks, themselves, and their families from avian influenza.

Introduction

Avian influenza A(H5) viruses, commonly referred to as bird flu, circulate among wild waterfowl and seabirds and are causing outbreaks in domestic poultry, dairy cows, and other mammals in the United States; 71 human cases of influenza A(H5) have been reported in the United States since March 2024. Three of these cases, including two deaths (1–4), occurred among persons who were owners of backyard flocks.

Surveys of U.S. backyard flock owners conducted in 2013 (5) and 2018 (6), found that a majority of respondents kept small flocks (fewer than 10 birds, primarily chickens) for <5 years. Most respondents were aware of avian influenza, and few reported using personal protective equipment (PPE) during regular interactions with their birds (6). To update and build on previous surveys, CDC and state partners conducted a survey among backyard flock owners aimed to assess knowledge of specific signs and symptoms of avian influenza and planned practices if their flock were to become infected with avian influenza viruses. These data might help guide and refine public health messaging to U.S. backyard flock owners.

 (SNIP)

Discussion

A majority of surveyed U.S. backyard flock owners had heard about avian influenza, were aware that U.S. backyard flocks have been infected, and knew that human cases of avian influenza have occurred in the United States. However, important gaps in knowledge and prevention practices remain among flock owners, suggesting opportunities for focused public health, animal health, and agricultural outreach.

(SNIP)

Backyard flock owners should know how to protect themselves from avian influenza. Although most survey respondents reported willingness to use some types of PPE, fewer indicated they would use eye protection or coveralls. Messages to flock owners could highlight reasons to use each piece of recommended PPE, when to use it, and how to use it correctly.

Recent incidences of influenza A(H5) human cases among backyard flock owners in the United States underscore the importance of flock owners knowing the signs and symptoms of possible human A(H5) virus infection. The survey identified limited awareness of nonrespiratory symptoms of avian influenza in humans (such as conjunctivitis, diarrhea, and vomiting) and low perceived personal risk, which could result in delays in seeking health care. Flock owners should be encouraged to seek prompt medical evaluation for any potential symptoms of avian influenza virus infection and report recent bird exposure to health care providers to support timely diagnosis and further infection prevention and control measures. 

(Continue . . . )

The need to improve both knowledge and biosecurity practices among backyard flock owners isn't just an American problem.  

Last March, in EFSA: Risk communication on Avian Flu Biosecurity, we looked at a proposed, phased 3-year program to increase biosecurity awareness in small holdings across the EU. 

As we discussed in 2024's Mixed Messaging On HPAI Food Safety, there is some degree of risk in the slaughtering of live birds and preparation of raw poultry; especially from birds raised at home or purchased from live markets.

PAHO (the Pan-American Health Organization) mentions this on their Avian Influenza landing page:  Plucking, handling infected poultry carcasses, and preparing poultry for consumption, especially in domestic settings, may also be risk factors.

Also in 2024 the WHO published  Interim Guidance to Reduce the Risk of Infection in People Exposed to Avian Influenza Viruses, which lists a number of `risk factors', including:

• keep live poultry in their backyards or homes, or who purchase live birds at markets;

• slaughter, de-feather and/or butcher poultry or other animals at home;

• handle and prepare raw poultry for further cooking and consumption;

Over the past few years the threat from H5N1 has grown markedly in the Western Hemisphere. Things we used to do without much thought - like raising a few chickens the backyard - carry more risks today. 

The $64 question is whether we can adjust to those changing risks fast enough to prevent even bigger bio-shocks in the future. 

CDC HAN #00530: Ebola Disease Outbreak in the Democratic Republic of the Congo and Uganda

 
Credit CDC

#19,168

While the full extent of the Ebola outbreak in the DRC and neighboring countries remains unclear, we are already seeing numbers that suggest this virus is spreading rapidly in the community.   

The latest CDC update reads:

New developments

• On May 17, an American who was exposed as part of their work caring for patients in DRC tested positive for Ebola Bundibugyo disease.

• The person developed symptoms over the weekend and tested positive late on Sunday.
• CDC is working hand-in-hand with the U.S. Department of State to move the patient to Germany for treatment and care. In addition to being a shorter flight time, Germany has previous experience caring for Ebola patients.
• High-risk contacts associated with this exposure are also being moved to Germany. 

• As of May 19, the DRC and Uganda Ministries of Health report the following:

• A total of 536 suspected cases, 105 probable cases, 34 confirmed cases, and 134 deaths
• In the last 24 to 48 hours, 26 new confirmed cases and 143 new suspected cases were identified,
• These numbers include 2 confirmed cases including 1 death in Uganda in people who traveled from DRC. No further spread has been reported.

• On May 18, CDC, the Department of Homeland Security, and other appropriate federal agencies took proactive public health measures to prevent Ebola from entering the United States.

• This is a rapidly evolving situation, and case counts are subject to change.
• More information about enhanced travel security measures is forthcoming.

Late yesterday afternoon the CDC issued the following lengthy HAN Advisory.  I've only posted some excerpts.  Those with specific interests (clinicians, public health workers, lab techs, etc.) will want to read the advisory in its entirety. 

I'll have a brief postscript after the break. 

Ebola Disease Outbreak in the Democratic Republic of the Congo and Uganda
May 19, 2026

 Distributed via the CDC Health Alert Network
May 19, 2026
CDCHAN-00530

Summary

The Centers for Disease Control and Prevention (CDC) is issuing this Health Alert Network (HAN) Health Advisory to alert clinicians, public health practitioners, and travelers about a new outbreak of Ebola disease in the Democratic Republic of the Congo (DRC) and Uganda caused by the Bundibugyo virus (species Orthoebolavirus bundibugyoense).

The risk of spread to the United States is considered low at this time. As a precaution, this Health Advisory summarizes CDC recommendations for U.S. health departments, clinical laboratories, and healthcare workers about potential Ebola disease case identification, testing, and biosafety considerations in clinical laboratories.

Background

On May 15, 2026, the Ministry of Health of the Democratic Republic of the Congo (DRC) confirmed an outbreak of Ebola disease in Ituri Province in northeastern DRC. As of May 16, 2026, a total of 246 suspected cases and 80 deaths have been reported. Laboratory analysis conducted by the National Institute of Biomedical Research (INRB) confirmed the cause as Bundibugyo virus infection in 8 of 13 samples collected from suspected cases associated with clusters of severe illness and deaths in the Mongbwalu and Rwampara health zones in Ituri Province. Patients presented with symptoms including fever, generalized body pain, weakness, vomiting, and in some cases bleeding. Several patients reportedly deteriorated rapidly and died. The outbreak is occurring in areas affected by insecurity, population displacement, mining-related population movement, and frequent cross-border travel, all of which may increase the risk of further transmission. In neighboring Uganda, health authorities confirmed Bundibugyo virus disease (BVD) in a patient who had traveled from DRC and later died while receiving care. Ugandan authorities have activated surveillance, screening, and response measures.

On May 15, 2026, CDC issued a Level 1 Travel Health Notice for people traveling to Uganda and a Level 3 Travel Health Notice for people traveling to DRC. On May 17, the World Health Organization determined this outbreak to be a public health emergency of international concern. As of May 18, no suspected, probable, or confirmed Ebola cases related to this outbreak have been reported in the United States.

This is the 17th recorded Ebola outbreak in DRC since the virus was first identified in 1976. The previous Ebola outbreak in DRC ended in December 2025. The Bundibugyo species of Ebola virus was first identified in Uganda in 2007 and has historically been associated with somewhat lower case fatality rates than other species of Ebola virus disease, though severe disease and death can still occur. Previous outbreaks of BVD have had mortality rates of approximately 25%-50%.

CDC is working through its country offices and partners in DRC and Uganda to provide technical assistance with disease tracking and contact tracing, laboratory sample collection and testing, virus sequencing, infection prevention and control (IPC) efforts, border health screening, and coordination with affected countries and international public health partners. Case numbers are subject to change as the situation evolves.

The risk of spread to the United States is considered low at this time. However, it is possible for travelers from affected areas in DRC or Uganda to enter the United States. Therefore, as an additional precaution, CDC is working to raise awareness of this outbreak among travelers, public health departments, public health and clinical laboratories, and healthcare workers in the United States.

Ebola disease is caused by a group of viruses known as orthoebolaviruses (formerly ebolavirus). Ebola disease most commonly affects humans and nonhuman primates, such as monkeys, chimpanzees, and gorillas. Four orthoebolaviruses cause illness in people, presenting as clinically similar disease:

• Ebola virus (species Orthoebolavirus zairense) causes Ebola virus disease.
• Sudan virus (species Orthoebolavirus sudanense) causes Sudan virus disease.
• Taï Forest virus (species Orthoebolavirus taiense) causes Taï Forest virus disease.
• Bundibugyo virus (species Orthoebolavirus bundibugyoense) causes Bundibugyo virus disease.

The incubation period for BVD ranges from 2 to 21 days after exposure. A person infected with an orthoebolavirus is not considered contagious until after symptoms appear. Early "dry" symptoms include fever, aches, pains, and fatigue and later "wet" symptoms include diarrhea, vomiting, and unexplained bleeding. Ebola disease is spread through direct contact (through broken skin or mucous membranes) with the body fluids (e.g., blood, urine, feces, saliva, semen, or other secretions) of a person who is sick with or has died from Ebola disease. Ebola disease can also be transmitted to humans from infected animals, or through contact with objects like needles that are contaminated with the virus. Ebola disease is not spread through airborne transmission.

In the absence of early diagnosis and appropriate supportive care, Ebola disease has a high mortality rate. There is currently no Food and Drug Administration (FDA)-licensed or authorized vaccine to protect against Bundibugyo virus infection. The Ebola vaccine licensed in the United States (ERVEBO®) is indicated for preventing Ebola disease due to a different species of Ebola virus (species Orthoebolavirus zairense) only, and based on studies in animals, this vaccine is not expected to protect against Bundibugyo virus or other orthoebolaviruses. There is currently no FDA-approved or authorized treatment for BVD, but there are therapies that have shown some efficacy in animal models. With intense supportive care and fluid replacement, mortality rates may be lowered.

CDC has developed recommendations for U.S.-based organizations (e.g., nongovernmental, faith-based, academic, or aid organizations) with staff working in affected areas: Recommendations for Organizations Sending U.S.-based Personnel to Areas with VHF Outbreaks.

Recommendations for Clinicians

Recommendations for Public Health Departments

Recommendations for Clinical Laboratory Biosafety

Recommendations for U.S. Travelers

CDC recommends avoiding nonessential travel to Ituri and Nord-Kivu provinces in DRC. If they travel to DRC, travelers should take precautions as described in CDC's level 3 Travel Health Notice, including taking steps to avoid possible exposure to BVD and monitoring themselves for symptoms while in DRC and for 21 days after leaving. Travelers who develop symptoms during this time should self-isolate and contact local health authorities or a clinician.

Travelers to Uganda are recommended to follow recommendations in CDC's level 1 Travel Health Notice including taking steps to avoid possible exposure to BVD and monitoring themselves for symptoms while in Uganda and for 21 days after leaving. Travelers who develop symptoms during this time should self-isolate and contact local health authorities or a clinician.

Recommendations for the Public

• Protect yourself and prevent the spread of BVD when living in or traveling to a region where Bundibugyo virus is potentially present or that is currently experiencing an outbreak.
• In affected areas, take the following actions to protect yourself: 

• Avoid contact with sick people who have symptoms such as fever, muscle pain, and rash.
• Avoid contact with blood and other body fluids.
• Avoid materials possibly contaminated with blood or other body fluids of people who are sick.
• Avoid semen from men who have recovered from BVD until testing shows that the virus is no longer in the semen.
• Avoid visiting healthcare facilities for nonurgent medical care or for nonmedical reasons.
• Avoid visiting traditional healers.
• Do not participate in funeral or burial practices that involve touching the body of someone who died.
• Keep away from bats, forest antelopes, non-human primates (e.g., monkeys, chimpanzees, gorillas), and avoid contact with blood, fluids, or raw meat from these or unknown animals.
• Do not enter areas where bats live, such as mines or caves.

• Monitor your health while you are in, and for 21 days after you return from, an area experiencing a BVD outbreak.

• If you develop any symptoms of BVD during this time, isolate (separate) yourself immediately from others, do not travel, and contact local health authorities or a healthcare facility for advice.
• Before you enter a healthcare facility, alert the healthcare providers of your recent presence in a BVD-affected area.

Over the past 3 weeks we've seen 2 viral outbreaks (hantavirus & Ebola) emerge from out of left field - and while I believe both will be contained - it is a reminder of how quickly the viral landscape can change. 

The next pandemic virus is likely already out there, in a bat, a mouse, or a bird; just looking for the right opportunity (or evolutionary change) to enable it to jump species and begin its world tour. 

Meanwhile we continue to dismantle our global surveillance and reporting systems, we resist aggressive testing of livestock, and we've cut funding for both basic research and public health systems.

But at least when next pandemic crisis invariably does appear, our leaders will be able to shake their heads and honestly say; `No one saw it coming.'