Outbreak Watch: November 4, 2026

Summary

Outbreaks don't always follow the patterns we expect, and this week's Outbreak Watch brings several developments worth a closer look.

New World screwworm detections continue to rise in the southwestern United States, while Washington's rapidly expanding H5N1 dairy outbreak has now been linked to three human infections, including a death. In the Democratic Republic of the Congo, the Bundibugyo Ebola outbreak continues to grow, with confirmed secondary transmission in Kenya and another imported case in Nigeria raising new questions about regional spread.

We're also following measles deaths in Pennsylvania and New York, continued locally acquired dengue transmission in Florida as cooler weather approaches, and significant international developments involving yellow fever, cholera, hand, foot and mouth disease, and Crimean-Congo hemorrhagic fever.

This episode looks beyond the case counts to explore what these developments tell us about transmission, surveillance, outbreak response, and the questions investigators are still trying to answer.

Listen here or scroll down to read full episode.

Full Episode

At our last Outbreak Watch check-in, USDA had confirmed 52 New World screwworm infestations in animals in the United States. Two cases were active. There had been one wild screwworm fly caught in a surveillance trap, and no confirmed infestations in wildlife. I was watching to see whether that fly was an isolated detection, or the beginning of something more persistent.

Well, the outbreak has grown a lot since then. And screwworm isn't the only outbreak where the evidence has shifted. Washington's H5N1 dairy detections have grown from two herds to 40. And CDC is now describing likely sustained domestic transmission of clade Ib mpox in the United States. Meanwhile, the Ebola outbreak in the Democratic Republic of the Congo continues to grow, and measles has claimed another child's life, this time in New York.

Let's start with screwworm, because the pattern is becoming harder to explain as a handful of isolated animal infestations.

New World screwworm: what are we missing?

On November 3, USDA's New World screwworm dashboard reported 91 cumulative animal cases in the United States: 90 in domestic animals and one in wildlife or a feral animal. Thirty-four domestic-animal cases were classified as active. Compare that with October 9, when we had 52 cases, all in domestic animals, and only two active. That's 39 additional confirmed animal infestations since the last episode. The number of cases still requiring treatment or other mitigation has also increased sharply. An active case is an animal-level status. It doesn't tell us how many flies are present in a county, or whether transmission has stopped around an animal once its case becomes inactive.

October's completed monthly count is…striking: 36 domestic-animal detections, compared with three in September and four in August. When I wrote about this in last week's newsletter, the October total was only 14 at that point. And the geography has also changed. Confirmed cases have been reported in Texas, New Mexico, and now Arizona, where a dog in Cochise County became the state's first confirmed case in late October.

There's also the wildlife question. On October 21, USDA announced an infestation in an elk in Pecos County, Texas. The first confirmed U.S. case in wildlife. The dashboard now lists five wild screwworm fly trap detections, up from the single fly we discussed last time. A trap detection tells us an adult fly was present in the environment. It doesn't tell us where that fly developed, which animal it came from, or whether a breeding population is now sustaining itself in the area. But five detections are a different surveillance picture from one.

The biology is what makes this difficult. the animal with the visible wound is only one part of the transmission cycle. For more on that, check out my episode on screwworm…it’s called On the Fly.

But we also need to consider how we find cases. A rancher sees a wound on a cow or a veterinarian examines a dog. Someone recognizes an unusual infestation, collects larvae, and sends them for identification. That system can work well for animals people see and handle. It's much harder with free-ranging wildlife. A wounded deer or elk may never be examined. An animal that dies in remote terrain may never be found. USDA has conducted targeted wildlife surveillance, so it would be wrong to say nobody is looking. But no wildlife surveillance program can inspect every single animal.

That is why I'm reluctant to interpret one confirmed wildlife case as evidence that wildlife are barely involved. We know at least one wild animal was infested. We know wild adult flies have been detected. We do not know how many wildlife infestations are going unobserved, and we can’t calculate that number from the dashboard. Nor can we say yet that a self-sustaining wildlife transmission cycle has been established. What I want to see next is where new animal cases and trap detections cluster, whether they recur in the same places, and what investigators learn from tracing the animals' movements and exposures. Are we finding more because surveillance is improving? Is local transmission intensifying? Probably both are worth investigating, but the relative contributions are unknown.

The immediate consequences are practical: animal health, livestock production, veterinary capacity, and the cost of surveillance and control. Sterile-fly releases are part of the response, because mating with sterilized males can suppress reproduction. But the effectiveness of a control program depends on knowing where the flies are. Right now, the domestic-animal case count is rising much faster than it was a month ago, and the wildlife side of the picture is still incomplete.

And there's another part of this outbreak that I think deserves attention: what it's costing us.

The United States eliminated New World screwworm decades ago, and keeping it out required continued investment. The sterile-fly program in Panama, which helped maintain a biological barrier against the parasite moving north, historically received about $20 million a year in federal appropriations.

Now consider what we're spending to respond to its return. According to the Congressional Research Service, USDA had already committed nearly a billion dollars in emergency funding for screwworm-related activities between fiscal year 2024 and May 2026.

That billion dollars is roughly equivalent to 50 years of the historical annual prevention budget. It's not a direct cost comparison, because we're building infrastructure that will be useful for years. But it does illustrate the scale of what happens when a biological threat gets ahead of our capacity to control it.

We knew this parasite was moving north. We knew sterile-fly production capacity was insufficient. And the administration made significant cuts to the programs protecting us from it…now we're trying to expand that capacity while the outbreak is already occurring.

I keep coming back to something that applies well beyond screwworm. Successful public health infection prevention programs are not self-sustaining. When you haven’t had to worry about an infectious disease for decades, it means those measures are working, not that the pathogens aren’t a problem. Elections have consequences.

For a deep dive into screwworm eradication and the start of this outbreak, check out my episode, On the Fly.

Clade Ib mpox: a change in the U.S. transmission picture

Now for something new. On November 2, CDC updated its assessment of clade I mpox in the United States. Since November 2024, more than 160 laboratory-confirmed clade I cases have been reported in at least 27 states and Puerto Rico. Many were associated with international travel or contact with people who had traveled. But since August of this year, an increasing proportion of cases have been reported in people without recent international travel or known links to travelers. CDC says presumed domestic transmission has now been reported in 16 jurisdictions, indicating a likely transition to sustained clade Ib transmission in the United States.

That's a change in how we should understand the outbreak. Imported cases can produce occasional local infections without establishing ongoing transmission. When investigators repeatedly identify cases with no apparent travel link across multiple jurisdictions, the possibility that transmission is continuing within domestic contact networks becomes much stronger. CDC is using the word 'likely' for a reason: exposure histories are incomplete, and not every infection can be linked to another confirmed case. But the pattern has moved beyond a simple sequence of travel-associated introductions.

Mpox spreads through close physical contact, including sexual contact, and contact with infectious lesions or contaminated materials. In recent clade I outbreaks, intimate and sexual contact has played a major role, although household transmission can also occur. Clade Ib is a genetic subdivision of clade I. You may remember that clade IIb drove the global mpox outbreak beginning in 2022.

CDC continues to assess the risk to most people in the United States as low. The virus isn’t spreading efficiently through every setting and not everyone faces the same exposure risk. People in sexual networks where mpox is circulating face increased risk and vaccination is an important tool for those who are eligible. Completing the two-dose JYNNEOS series is important for people at risk.

The question now is how much transmission is being missed. People with mild or atypical lesions may not seek testing. Clinicians may not always request clade-specific testing. Surveillance can tell us a lineage is present, but reconstructing who infected whom is harder. I’ll be watching for evidence about the size and duration of domestic transmission chains. For a full episode on mpox, check out Under the Skin.

H5N1 in Washington dairy cattle: two herds became forty

Now on to my home state of Washington, where the H5N1 outbreak in dairy cattle has expanded rapidly, and there have been some concerning developments involving human infections.

By October 30, Washington had recorded 40 affected dairy herds: 39 in Yakima County and one in Benton County. The Benton detection was confirmed October 23 and announced October 26. Routine surveillance identified the virus before obvious illness was observed, so the recognized outbreak has expanded both in number and geography.

And we're now seeing the human consequences of that outbreak. Washington confirmed its first human H5N1 case associated with infected dairy cattle on October 15. That patient, a dairy worker in Yakima County, experienced mild illness and was not hospitalized. But two additional human cases have since been reported, including one person who developed severe illness, was hospitalized, and died on November 1. The third patient experienced mild illness and was not hospitalized. All three had exposure to infected dairy cattle in Yakima County.

This is the first reported U.S. death from H5N1 in 2026, and particularly concerning because it appears to be the first U.S. fatality associated with exposure to infected dairy cattle. There is still no evidence of human-to-human transmission, and the risk to the general public remains low. But these cases are a reminder that exposure to infected cattle can result in serious illness, even though many of the human infections identified among dairy workers so far have been relatively mild.

Sequencing from two Yakima farms identified B3.13, the lineage circulating in U.S. dairy cattle since 2024. We don't know at this point how the virus reached Washington or moved among farms. Cattle movements, contaminated equipment, and other farm connections are hypotheses for investigators to test. Infection can involve the mammary gland, and milk surveillance can detect viral material even when clinical signs are subtle. Pasteurized milk is safe, but workers handling infected animals and raw milk face different exposure risks.

I'm curious whether these 40 herds reflect one introduction followed by farm-to-farm spread, or multiple introductions. And with three human infections now identified, including a death, understanding those transmission pathways matters not only for protecting livestock, but also for preventing further occupational exposures.

And one brief H5 update from Australia: South Australian authorities confirmed another H5-positive common dolphin found dead near Victor Harbor on October 31. The state's wildlife outbreak has now produced hundreds of confirmed detection events, although officials say the frequency of new detections has declined. Preparations are also underway to vaccinate vulnerable wild little penguin colonies. There's no evidence from this dolphin finding of sustained transmission among dolphins, but it is another reminder of the range of wildlife being affected by H5 influenza.

For a deeper dive into bird flu check out my episode, Fowl On the Play as Bird Flu Heats Up

Ebola: Secondary Transmission in Kenya and Another Imported Case in Nigeria

Now let's return to the Ebola outbreak in the Democratic Republic of the Congo, where the situation continues to deteriorate.

In our last episode, the DRC had reported 8,728 confirmed cases and 4,205 deaths across 64 health zones in seven provinces. According to the November 1 situation report, published November 2, those totals have now reached 10,532 confirmed cases and 5,126 deaths. That's an increase of 1,804 cases and 921 deaths since our last update, with an overall reported case fatality ratio of 48.7 percent.

The outbreak has now affected 67 health zones across eight provinces. Ituri remains the epicenter, accounting for more than 70 percent of all confirmed cases. But North Kivu is currently reporting the largest share of new infections.

And the response is struggling in several areas. More than 36,000 contacts are currently under monitoring in the six provinces that submitted surveillance data, but only 84 percent were reached during the latest reporting period. That's still below the response target of 95 percent. In North Kivu, the contact follow-up rate was 79 percent, and in Tshopo, it was only 66.6 percent.

The situation in Tshopo is especially concerning. Response activities in the Bafwasende health zone have been suspended since October 24, amid security incidents and disruptions involving healthcare workers. The situation report also notes that two confirmed Ebola patients who left isolation have not yet been located, and that a building at the Ebola treatment center was set on fire.

These are the kinds of conditions that make interrupting Ebola transmission extremely difficult. Contact tracing depends on people being able to reach exposed individuals, monitor them, and arrange testing and isolation when symptoms develop. When response teams can’t operate safely, those opportunities are lost.

But there's another development we need to discuss, because it directly follows a story from our last episode.

You may remember the man who traveled from the DRC through Uganda to Kenya in early October. He became Kenya's first imported case of Bundibugyo Ebola during this outbreak, and at the time, authorities were still trying to locate and monitor his contacts. There was no confirmed secondary transmission when we last discussed the case.

We now know that eight additional people became infected.

According to the European Centre for Disease Prevention and Control, Kenya had confirmed nine cases by October 23: the original imported case and eight secondary infections. Four of those secondary cases occurred among family members, and four among healthcare workers. All eight were linked to that one imported patient and were already in quarantine when they developed symptoms.

And that is great news, that the secondary cases were identified among people who were already being monitored. That means contact tracing successfully identified the known transmission cluster before those eight people became symptomatic.

As of October 22, Kenyan authorities were following all 135 listed contacts. A recent Kenyan update reports two deaths in that cluster.

The fact that four healthcare workers were infected also raises questions about when the patient was recognized as a possible Ebola case and what infection-prevention measures were in place during his care.

And Kenya is no longer the only country to report an imported case associated with this regional outbreak. On October 20, Nigeria confirmed Bundibugyo Ebola in a woman who had traveled from Uganda to Abuja on October 3. She reportedly spent about two and a half weeks in Uganda before arriving in Nigeria, developed symptoms around October 6 or 7, and was admitted to a hospital on October 11. Her infection wasn't confirmed until October 20.

But there's a question investigators are still trying to answer: Where did she become infected?

Swiss officials, who identified the patient as the wife of a Swiss diplomat, say she had not traveled to the DRC and was likely infected during her stay in Uganda. Ugandan authorities have disputed that account and suggested she may have traveled into the DRC. The World Health Organization says it has no information confirming that she visited the DRC, and the source of her infection remains under investigation.

There's also a possible connection to the imported case in Kenya. Both patients departed through Uganda's Entebbe International Airport on October 3, reportedly about 40 minutes apart. Africa CDC is investigating whether they might have crossed paths.

Now, that doesn't mean one infected the other. Ebola spreads through direct contact with the bodily fluids of someone who is symptomatic, or with materials contaminated by those fluids. Two people passing through the same airport around the same time is not enough to establish an epidemiological link. Investigators would need evidence of an actual exposure, and the timing of both patients' illnesses would also need to make sense.

And if the Nigerian patient was infected in Uganda, rather than the DRC, that raises another question. Uganda's last reported confirmed Bundibugyo case was in June. So was there an infection that went undetected? Was the patient's exposure connected to a known case or another infected traveler? Or is some part of the travel or exposure history still missing?

We don't have those answers yet.

And the patient arrived in Nigeria before she reportedly developed symptoms, which makes exposure during the flight less likely based on what we currently know about Ebola transmission. But she was symptomatic for several days before her diagnosis, and that is the period Nigerian authorities have been investigating through contact tracing.

As of ECDC's October 23 assessment, 44 contacts were being monitored in Nigeria, with no confirmed secondary transmission reported at that time.

So we now have a very large, ongoing outbreak in the DRC, confirmed secondary transmission following an imported case in Kenya, and another imported case identified in Nigeria.

The Kenya cluster is an important demonstration of why contact tracing matters. Eight people were infected, but all eight were already under quarantine when they developed symptoms. That's exactly what public health teams are trying to accomplish: identify exposed people before they become ill and potentially expose others.

In the DRC, where tens of thousands of contacts need monitoring and response activities are being interrupted in some areas, accomplishing that consistently is much more difficult.

So now I’m watching whether Kenya identifies any infections beyond the known cluster, whether Nigeria detects secondary transmission, and whether contact follow-up and response access improve in the DRC's most affected health zones.

For a deep dive into Ebola, check out my episode, Containing Ebola.

Measles: more cases, and another death

And now back to the US for the great measles comeback of 2026. Pennsylvania's reported measles total has risen to 1,433 as of November 2. Hospitalizations increased to 269, while the state continues to report five measles-associated deaths. A sixth death, involving a 39-year-old Franklin County woman who had previously been diagnosed with measles, is still under investigation. The coroner suspects a cardiac event potentially related to the woman's recent measles illness, while the state is still determining whether the evidence supports classifying it as a measles-associated death.

And in New York, health officials have confirmed the state's first measles-associated death in more than 30 years. The child was a seven-month-old boy in Lewis County who died November 1. He was unvaccinated, but there's an important distinction here: at seven months, he was younger than the age for the routinely scheduled first MMR dose.

That routine schedule isn't based on the vaccine being unsafe for younger infants. It's largely because maternal antibodies can interfere with the immune response, making vaccination before 12 months less likely to provide reliable, lasting protection. During outbreaks, however, public health officials may recommend an early MMR dose for infants as young as six months to provide protection when their risk of exposure is elevated.

And because that early dose may not produce sufficiently durable immunity, it doesn't count toward the routine two-dose series. A baby vaccinated at six or seven months still needs the usual doses beginning at 12 months.

That's an important distinction, particularly during outbreaks. An early dose can help protect an infant during a period of increased risk, while the later doses are still needed to establish more reliable long-term protection.

Measles spreads through the air extremely efficiently, and people can be infectious before the rash appears. Complications can include pneumonia and encephalitis. Infection can also interfere with immune memory, making people more vulnerable to other infections afterward. Two doses of MMR vaccine are about 97 percent effective at preventing measles. The rising hospitalization count is a reminder that the familiar rash is only one visible part of a disease that can have much more serious consequences. For a deep dive check out my episode, The Monster That is Measles

Florida Dengue: Will Cooler Weather Interrupt Transmission?

Florida's week 42 arbovirus surveillance report, covering October 18 through 24, lists 485 locally acquired dengue cases in 2026 across 12 counties. Sixty locally acquired cases were reported during that week, along with 20 dengue-positive mosquito pools identified so far this year. As a reminder, these cases represent transmission occurring within Florida not imported travel-associated cases.

We're now in late October for reporting, and Florida still has significant numbers of locally acquired infections. Cooler temperatures and shorter days should eventually reduce mosquito activity and opportunities for transmission, but in Florida, especially farther south, the seasonal decline may be less pronounced than in more temperate regions.

So, will transmission taper off as we move into winter, or will some communities continue seeing locally acquired cases?

And while I'm watching whether Florida's dengue transmission continues into the cooler months, Bangladesh offers a reminder of how substantial the burden of dengue can become in places where the disease is already well established. October was reportedly Bangladesh's deadliest month for dengue so far this year, with 173 deaths. By October 30, the country had recorded more than 133,000 dengue-related hospital admissions and 418 deaths in 2026.

Those figures illustrate why the persistence of dengue transmission deserves attention, even when an outbreak initially appears geographically limited.

And if you'd like a deeper dive into dengue and how it has established a foothold in Florida, check out my episode, Dengue Next Door.

International watch

A few additional international developments are also worth watching.

In Venezuela, yellow fever continues to cause serious illness and deaths. According to an update published November 2, the country had recorded 14 confirmed cases and six deaths in 2026, as of October 17. Cases have been reported in six states, and yellow fever virus has also been detected in nonhuman primates across a broader area of the country. Those animal detections can provide evidence of where the virus is circulating in forest transmission cycles, even when human cases are uncommon. Vaccination remains the most important protection for people living in or traveling to areas where yellow fever is a risk.

In Zambia, the cholera outbreak is expanding. As of November 2, officials had reported 1,958 cases, including 303 laboratory-confirmed infections, and 40 deaths since the outbreak began in late July. Just six days earlier, the reported total was 1,548 cases and 30 deaths, so the increase has been substantial. Cases have now been reported across seven provinces. And although cholera is treatable, severe infections can cause life-threatening dehydration very quickly. Access to safe water, sanitation, and timely rehydration treatment are central to controlling the outbreak and preventing deaths.

In Vietnam, Ho Chi Minh City is experiencing a significant increase in hand, foot and mouth disease. By October 31, the city had reported more than 44,000 cases and five deaths this year, an increase of more than 65 percent compared with the same period last year.

One reason health officials are particularly concerned is the circulation of enterovirus A71, or EV-A71. Hand, foot and mouth disease can be caused by several different enteroviruses, but EV-A71 is especially concerning because it has a greater association with severe neurological complications, including encephalitis and paralysis. Most children infected with EV-A71 experience mild illness, but a small proportion develop serious complications. So while we can't assume that all of Vietnam's reported hand, foot and mouth disease cases are caused by EV-A71, its circulation is an important finding, particularly with hospitals reporting critically ill children.

And finally, Afghanistan continues to report substantial Crimean-Congo hemorrhagic fever activity. The latest consolidated figures I could verify show 1,669 reported cases and 71 deaths through September. That's already more reported cases than the country recorded during all of 2025, although deaths remain below last year's total.

It’s important to keep in mind that with CCHF, many reported cases are suspected rather than laboratory-confirmed, so the totals should be interpreted accordingly. But the overall burden is significant.

These outbreaks involve very different pathogens and transmission systems, but they share a practical challenge: recognizing ongoing transmission early enough to prevent additional severe illness and deaths.

Closing

There's a common problem running through several of these stories. Surveillance reveals only what it is capable of finding. Milk testing can identify H5N1 before a farmer notices a sick cow. Mpox cases without travel links can expose domestic transmission that was already occurring. A screwworm trap tells us a wild fly was present, but not which animals it encountered. And in the DRC, the percentage of Ebola contacts reached tells us more than the cumulative case count can.

For screwworm, the question I started with is still the one I want answered. Are we seeing more intense local transmission, better detection, or some combination? The jump from 52 to 91 animal cases is real. So are the five wild-fly detections and the first confirmed wildlife infestation. But the part of the transmission cycle we can’t observe clearly may be just as consequential as the part appearing on the dashboard. I'll keep following what the investigations actually establish.

So that's where things stand this week. If you want weekly outbreak updates, subscribe to my free newsletter Field notes.

Until next week, stay healthy, stay informed and spread knowledge not disease.

ANNOTATED CITATIONS

Accessing the literature: Whenever possible, I've linked directly to free full-text articles and books that are legally available online. For subscription-only journal articles, many researchers are happy to share a personal copy of their work if you contact the corresponding author. For books, I've included links to free online lending copies or library catalogs when available. If a title isn't freely available online, I've linked WorldCat to locate it at a nearby library or you can ask your local library about interlibrary loans.

Each citation is annotated to explain how the source connects to the episode and to help listeners who want to explore the science in greater depth.

DRC Ebola

Democratic Republic of the Congo Ministry of Health. 2026. Ebola Situation Report No. 171. 

🌐 Free online resource https://insp.cd/sitrep-n171-mve-bdbv-01-11-2026/

➡ Official outbreak situation report providing the most current case counts, deaths, affected health zones, and operational updates from the DRC Ministry of Health.

European Centre for Disease Prevention and Control. October 27, 2026. ECDC to deploy experts as Ebola cases emerge in Kenya and Nigeria

🌐 Free online resource — https://www.ecdc.europa.eu/en/news-events/ecdc-deploy-experts-ebola-cases-emerge-kenya-and-nigeria

➡️ ECDC describes its deployment of epidemiological experts to Nigeria following imported Bundibugyo Ebola cases in Kenya and Nigeria. The update covers international response coordination, surveillance and contact-tracing support, and the agency's assessment that the overall risk to the EU/EEA population remains very low.

Pennsylvania Department of Health. 2026. Measles.

➡️ Official state public-health resource providing measles surveillance information, outbreak updates, vaccination guidance, and prevention recommendations. Serves as the primary reference for Pennsylvania's outbreak figures and public-health messaging; figures should be attributed to the specific reporting date used in the episode.

🌐 Free online resource — https://www.pa.gov/agencies/health/diseases-conditions/infectious-disease/measles

New York State Department of Health and Lewis County Public Health. November 2, 2026

➡️The agencies confirm New York's first known measles-associated death in more than 30 years, involving a child in Lewis County during an ongoing outbreak. The statement emphasizes measles complications, vaccination, and outbreak-specific guidance recommending an early MMR dose for infants aged 6–11 months at increased risk of exposure, followed by the routine two-dose series.

🌐 Free online resource https://healthweb-back.health.ny.gov/press/releases/2026/2026-11-02_measles.htm

USDA Animal and Plant Health Inspection Service (APHIS). 2026. Current Status of Confirmed U.S. Cases of New World Screwworm.

➡️ Official USDA dashboard tracking confirmed New World screwworm detections in the United States and summarizing the federal response.

🌐 Free online resource https://www.aphis.usda.gov/animals/animal-health/livestock-and-poultry-disease/current-status/us-confirmed-cases-new-world

Centers for Disease Control and Prevention. November 2, 2026

➡️CDC reports more than 160 laboratory-confirmed clade I mpox cases in at least 27 U.S. states and Puerto Rico since November 2024. Presumed domestic transmission has been identified in 16 jurisdictions, suggesting a likely transition to sustained clade Ib transmission in the United States.

🌐 Free online resource https://www.cdc.gov/monkeypox/situation-summary/

WSDA. 2026 HPAI (H5N1) in Cattle: Producer Resources and Detection Table

➡️WSDA's official surveillance table documents 40 affected dairy herds in Washington through October 30, including 39 in Yakima County and one in Benton County. The page also identifies the B3.13 lineage in samples from two Yakima farms and provides guidance on testing, reporting, and biosecurity.

🌐 Free online resource https://agr.wa.gov/departments/animals-livestock-and-pets/avian-health/avian-influenza/hpai-%28h5n1%29-in-cattle-producer-resources

WSDA confirms HPAI in dairy herd in Benton County — October 26.

➡️The accompanying news release confirms detection through routine surveillance, laboratory verification, quarantine, and ongoing biosecurity measures.

🌐 Free online resource https://agr.wa.gov/about-wsda/news-and-media-relations/news-releases

Florida Department of Health. 2026. Arbovirus Surveillance Week 42.

➡️Florida's Week 42 surveillance data document 485 locally acquired dengue cases across 12 counties during 2026, including 60 newly reported cases that week, along with 20 dengue-positive mosquito pools. The findings demonstrate continued local dengue transmission into autumn, with Hillsborough County accounting for most reported cases.

🌐 Free online resource https://www.floridahealth.gov/statistics-data/population-surveillance/arbovirus-surveillance/

UK National Travel Health Network and Centre (NaTHNaC). November 2, 2026

➡️NaTHNaC reports 14 confirmed yellow fever cases and six deaths in Venezuela during 2026, as of October 17. Cases occurred in six states, with additional detections in nonhuman primates across several regions. The report supports discussion of ongoing sylvatic circulation and the importance of vaccination in affected areas.

🌐 Free online resource https://travelhealthpro.org/diseases/yellow-fever

UK National Travel Health Network and Centre (NaTHNaC). November 2, 2026

➡️NaTHNaC reports 1,958 cholera cases, including 303 laboratory-confirmed cases, and 40 deaths since the outbreak was declared on July 28. Seven provinces have reported cases.

🌐 Free online resource https://travelhealthpro.org.uk/outbreaks

Vietnam News, citing Ho Chi Minh City Department of Health. October 31, 2026

➡️Reports more than 44,000 hand, foot and mouth disease cases, five deaths, and over 1,600 outbreaks in Ho Chi Minh City during 2026. The report also documents circulation of enterovirus A71, a cause of HFMD associated with potentially severe neurological complications, and intensified prevention measures in schools and childcare facilities.

🌐 Free online resource https://vietnamnews.vn/society/1803314/hcm-city-steps-up-hand-foot-and-mouth-disease-prevention-as-cases-exceed-44-000.html

UK Health Security Agency. Epidemiological week 43, 2026

Outbreaks Under Monitoring: Week 43

➡️UKHSA summarizes Afghanistan's CCHF surveillance, reporting 1,669 cases and 71 deaths during 2026 through September. September alone accounted for 220 newly reported suspected cases and five deaths. The report notes that the cumulative case count has exceeded the total reported in 2025, although deaths remain lower.

🌐 Free online resource https://www.gov.uk/government/publications/outbreaks-under-monitoring-in-2026/outbreaks-under-monitoring-week-43-week-ending-25-october-2026