r/ContagionCuriosity

In Michigan, the number of reported cases has risen to 572 as of Saturday, July 4, up from 170 on Tuesday, June 30. Cases remain the highest in Monroe, Lenawee, Washtenaw, Wayne, Shiawassee, Jackson, Oakland and Livingston counties.

As of July 4, 2026, no specific produce grower/supplier, or specific produce type has been identified as the source of the outbreak.

Cyclosporiasis is an intestinal illness caused by the Cyclospora parasite. People can become infected by consuming food or water that contains the parasite. Cyclospora infects the small intestine (bowel) and usually causes frequent, watery and explosive diarrhea. The time between being exposed and becoming sick is usually about one week but can range from two days to two weeks or more. Untreated, the illness may last from a few days to more than a month. Symptoms may go away and then return.

Cyclosporiasis is not usually life-threatening, but dehydration from frequent bouts of diarrhea can cause severe illness, particularly among younger or older people and those who have weakened immune systems.

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This appears to be a national outbreak affecting over 17 states, but cases have been concentrated in Michigan.

Cyclospora outbreak sickens almost 150 people (June 29)

CDC Surveillance of Cyclosporiasis

Three days after Matt Wappett finished a rafting trip in the Grand Canyon, he landed in the emergency room with a massive knee infection. While it improved with the help of antibiotics, Wappett’s general health continued to deteriorate over the following weeks. Through social media, Wappett recently learned he’s not the only paddler suffering.

“It’s just felt like having a flu for the last month, which is kind of crazy, and I don’t know and the doctors right now don’t know if that infection that I had in my knee is related to it. Nobody seems to know,” he said.

The National Park Service is now leading an investigation, hoping to discover what’s causing the mystery illness in Grand Canyon rafters.

Wappett’s group launched in mid May and took out on June 2. In the month since, Wappett has suffered from constant aches, joint pains and fever. He has also been diagnosed with pneumonia.

“I was telling my wife the other day, I’m like, I don’t know if I can go on like this. This is awful. You wake up every morning and every joint hurts. It’s just brutal, and I’ve never had anything like this,” Wappett said.

Wappett thought he was going crazy or being dramatic until he saw a post in a Grand Canyon boaters Facebook group on July 1. In the post, paddler Steven King shares that four of 16 people in his group started experiencing fever, fatigue, severe localized muscle pain and fluid in their lungs about a week after their rafting trip in June.

“I mean, it just takes one person to say, oh I’m experiencing this. If he wouldn’t have posted that, I would have still just been assuming that I’ve got a month-long flu,” said Wappett.

Since sharing the post, at least five other rafters have contacted King saying members of their crews are experiencing similar symptoms. According to King, all were on the river in May and June.

Both Wappett and King are waiting on medical tests, currently left with more questions than answers. Wappett’s doctor is considering valley fever, dengue fever, and hantavirus, while King says members of his group have reported an extensive list of illnesses under consideration, including bacterial infections, Lyme disease, West Nile virus, and Rocky Mountain spotted fever.

“I just want to feel normal again. I was supposed to go on the Salmon River in two weeks, and I’m at the point now where I’m like, I can’t go to the Salmon because I’m just not well,” said Wappett.

A spokesperson for Grand Canyon National Park confirmed that the National Park Service (NPS) is aware of the reported illness. The NPS Office of Public Health is leading an investigation in coordination with public health partners.

In a written statement, the NPS shared, “At this time, the investigation is ongoing, and we are not able to comment on the extent of the illnesses, potential diagnoses or other details while the investigation is underway. We will share additional information with the public as it becomes available.” [...]

https://archive.is/KQLOq

Jamestown Canyon virus has been circulating in northeastern North American mosquitoes since before the founding of the United States. Few physicians have diagnosed a case. A new study in Current Biology, built on 658 viral genomes sequenced mostly from mosquitoes in the northeastern United States, with additional samples from North Dakota, has produced the most detailed reconstruction yet of the virus’s centuries-long evolutionary history. What it reveals is a pathogen with an unusually complex life cycle, even by the standards of mosquito-borne viruses.

Jamestown Canyon virus was first isolated from mosquitoes near Jamestown, Colorado, in 1961. Connecticut’s surveillance program found it in 26 mosquito species between 1997 and 2022, and diagnosed human cases have been reported from 26 states, making it one of the most widespread arboviruses in North America. White-tailed deer are the main amplification host in much of the virus’s range. The virus can cause fever, headache and fatigue. In severe recognized cases it can invade the nervous system, causing meningitis or encephalitis. Twelve people have died.

Those numbers, 336 diagnosed cases since 2011 and 227 hospitalizations as summarized by the new study, are almost certainly a vast undercount. After the CDC began routine Jamestown Canyon virus IgM testing around 2013, reported cases jumped seventeen-fold, from an average of fewer than two per year to nearly thirty. Better detection and rising clinician awareness probably explain much of the jump, though surveillance data alone cannot rule out changes in incidence or exposure.

Seroprevalence surveys, which screen blood for antibodies that mark a past infection, suggest the true burden is far larger. A 2025 blood-donor study in selected endemic counties of Massachusetts, Minnesota and Wisconsin found neutralizing antibodies in roughly one in five donors. In Nova Scotia, 88% of deer and 21% of humans tested seropositive. Most infections produce no symptoms, or symptoms indistinguishable from a summer flu, and are never attributed to a cause.

The ecological story behind Jamestown Canyon virus will sound familiar to anyone who has followed Lyme disease, though the parallel is looser than it looks. Deer matter to both, but differently. White-tailed deer are the amplification host for Jamestown Canyon virus, the animal in which it multiplies. For Lyme disease, deer feed the adult ticks that carry the bacterium but do not transmit it themselves; the spirochete is maintained by small mammals and birds, especially white-footed mice. What the two share is terrain: the fragmented woodlands and suburban forest edges of the northeastern United States, rebuilt by a transformation that began more than a century ago.

By the late 1800s, deforestation and unregulated hunting had driven deer populations in the Northeast to near zero. Forests were cleared for agriculture and fuel. Then the farms were abandoned, the forests grew back and the deer returned. The same reforestation that helped set the stage for the Lyme epidemic may also have rebuilt habitat important to Jamestown Canyon virus: vernal woodland pools where its key vectors breed, among them Aedes canadensis, Aedes provocans and Aedes abserratus, connected by corridors of regrown forest that deer move through freely.

The new genomic study fits this history, though it cannot by itself show that reforestation caused the virus’s return to Connecticut. The research team, led by Ellie Bourgikos and Nathan Grubaugh at the Yale School of Public Health, estimates that one of the virus’s two major lineages arrived in the Northeast by the early 1700s. Genetic reconstruction places the surviving descendants of that lineage in New York for roughly two centuries before their inferred introduction into Connecticut around the early 1900s, during the broader period of forest regrowth. At least four separate introductions into Connecticut have occurred since.

The most surprising finding is how slowly this virus evolves. Jamestown Canyon virus accumulates genetic changes 10 to 100 times more slowly per calendar year than dengue, Rift Valley fever or chikungunya. The reason is ecological, not molecular. The virus spends approximately ten months of every year locked inside dormant mosquito eggs that overwinter beneath leaf litter and snow, with little to no viral replication, so few new mutations enter the population. Only during a brief two-month window in late spring and early summer, when those eggs hatch and the emerging mosquitoes begin feeding on deer, does the virus replicate. During that active season its estimated evolutionary rate falls within the range of other mosquito-borne RNA viruses. The annual average is slow because the molecular clock nearly stops for most of the year.

This deep freeze helps make the phylogenetic reconstruction possible. Three centuries of slow evolution have left enough genetic variation to read the virus’s history, but not so much that the signal is overwritten. The same feature that makes Jamestown Canyon virus hard to study by conventional epidemiology — its long, invisible dormancy — is precisely what makes it visible to genomic analysis.

The study proposes that Jamestown Canyon virus persists through two interlocking transmission cycles, each driven by a different type of mosquito. The maintenance cycle appears to be driven mainly by univoltine Aedes species, mosquitoes that produce a single brood per year. These emerge in spring from woodland pools, feed on deer, and some infected females lay eggs that already carry the virus. The eggs enter dormancy and survive the winter, restarting the cycle the following year. The phylodynamic model inferred that the virus spent roughly 80 to 90 percent of its time in these single-brood mosquitoes.

The diffusion cycle involves multivoltine mosquitoes, especially Anopheles species, which produce several broods across the summer. These amplify the virus and occasionally push it into new territory, but their contribution is episodic. They produce short geographic bursts, not sustained expansion. The virus spreads at roughly 30 to 60 square kilometers per year, a rate more like some slow-moving tick-borne viruses such as Powassan than the mosquito-borne viruses usually used for comparison. [...]

MONTRÉAL — A measles outbreak in Quebec has risen to 27 cases, the majority of which are in the Quebec City area.

Health officials say the most recent case was reported on June 28.

Officials say 10 cases were reported last week in the Portneuf regional county municipality, west of the provincial capital.

Exposures sites include the emergency room at the St-Raymond hospital and at grocery stores and pharmacies in Pont-Rouge, Que., and Donnacona, Que.

Other cases have been reported since early June in Montreal, Laval, and in the Montérégie, Laurentians and Lanaudière regions.

Since 2024, Quebec has experienced three other measles outbreaks, the most recent of which started in November 2025 and ended in February 2026. [...]

The World ⁠Health Organization on Thursday declared the ⁠hantavirus ⁠outbreak ​linked to a cruise ⁠ship over after the last identified ⁠contact of an ​exposed ‌person ‌completed quarantine and tested ‌negative for the virus.

The outbreak, which infected 13 people and ‌killed three, involved the Andes virus, ​a rare hantavirus strain that typically circulates in ⁠Argentina and Chile. ​The cruise ​ship, MV Hondius, ​set off ​from ‌Argentina ​on ​1 April.

The Air Force has acknowledged that the recent death of a recruit in basic training at Joint Base San Antonio-Lackland was caused by a flu virus that has swept the base, according to U.S. Rep. Joaquin Castro.

It was the firm confirmation that Keon Talik McDaniel, 25, died of influenza. Previously, the Air Force said only that McDaniel, who was in his sixth week of basic training, suffered "a medical emergency" and was taken to Brooke Army Medical Center, where he died. Air Force officials did not disclose whether he had contracted the flu.

"The Air Force confirmed that trainee Keon McDaniel died from the flu during the outbreak at Lackland Air Force Base in San Antonio," Castro, a San Antonio Democrat, said on Tuesday.

He and two fellow Democratic lawmakers called for federal legislation to require flu vaccinations for all military personnel. Defense Secretary Pete Hegseth rescinded the vaccine requirement in April, and in May, flu began spreading at Lackland, which is the hub of Air Force basic training, graduating 35,000 airmen every year.

When the outbreak became public on June 18, 160 recruits were said to have been infected. By June 25, the number of cases had reached 284, Castro said Tuesday. He said the numbers were the most recent he had been able to obtain from the military. A week earlier, there were a reported 222 cases.

The Air Force said it could neither confirm nor deny the latest figures offered by the congressman. After the virus began spreading at Lackland, the Pentagon suspended the voluntary vaccine policy for recruits at the base; they once again must be vaccinated.

Reps. Chrissy Houlahan, D-Pa., and Gilbert Cisneros, D-Calif., joined Castro on Tuesday in proposing to amend the National Defense Authorization Act, which funds the military, to make flu shots mandatory for all service personnel. So far, they said, Republicans had blocked the amendment.

"In April, Secretary Hegseth called the flu mandate 'irrational and absurd,'" Castro said at a Capitol Hill news conference. "What's absurd about keeping those who serve our nation safe? No president or secretary should be able to play politics or put the health of our troops at risk."

Houlihan is an Air Force veteran and a member of the House Armed Services Committee. "I know that military readiness is built on discipline, professionalism and on leaders to make decisions based on evidence and not on ideology," she said. "Readiness begins and ends with healthy troops. That is why what is happening at Lackland is so deeply disturbing and troubling.

"Nearly 300 service members have become ill. Several have been hospitalized. One young American has reportedly died from flu-related causes," she said.

https://archive.is/GwIzS

The first time Lowri Denman knew something was wrong was when she made the horrifying discovery of a metre-long tapeworm after going to the toilet.

"It looked absolutely disgusting, like Sellotape with like little ridges in it," said the 42-year-old from Carmarthen.

It was the first symptom of neurocysticercosis, which left Lowri with 38 parasites in her brain causing extreme headaches, seizures and psychosis.

She is one of only a handful of people in the UK who are diagnosed with the brain infection each year, which is caused by the larvae of the pork tapeworm.

After spending years regaining her health, Lowri wants to turn her ordeal into something positive by raising awareness of the condition.

Lowri, who works in media, went on a three-month trip around India in 2007. This is where her doctor - Dr Brendan Healy, a consultant in infectious diseases and microbiology - believes she picked up the infection.

Lowri made the decision to avoid meat for the trip, hoping it would help her to avoid food poisoning, but Dr Healy believes she inadvertently ate pork that contained microscopic tapeworm eggs.

It was not until three years later, in 2010, that Lowri discovered the tapeworm when in a restaurant toilet and flushed it down the loo.

She went to the GP but stool tests came back satisfactory and she was feeling well so life continued as usual.

Within a year she began getting terrible headaches.

Then, in 2011, she suffered her first seizure.

"I was really starting to struggle getting some words out," she said.

"The next thing I came around and I was in an ambulance and I was like 'how has that happened? Why?'"

A hospital stay, CAT scan and MRI scan followed and Lowri was told to come in for the results.

"The doctor sat me down and said, 'right, okay, we've looked at your scans and we've found 38 parasites on your brain'," said Lowri.

"Me and my mum were just jaws on the floor like, 'what on earth, what is that?'"

Initially they thought it was toxoplasmosis, an infection spread through contact with infected cat faeces.

But then Lowri's mother asked if her seizure could be linked to the tapeworm she had discovered a year earlier.

After further investigations she was finally diagnosed with neurocysticercosis.

According to the World Health Organization (WHO), humans are infected by consuming food such as raw or undercooked pork, water contaminated with tapeworm eggs, or through poor hygiene practices.

It is exceptionally rare in the UK and cases are almost exclusively seen in individuals who have migrated from endemic regions.

"At that point there's so many questions because you just don't know what's ahead of you with your health," said Lowri.

"The panic of what's next, what am I going to have to deal with, what medication am I going to go on, can I go back to work?"

She stayed in hospital for two weeks, and was put on anti-parasitic drugs and steroids.

For a while, the treatment seemed to have worked.

She had several years of good health where she was able to go on a trip with her sister to New Zealand, move to Bristol, take circus classes and run half marathons.

But then she collapsed in work.

Scans found huge swellings on Lowri's brain around the parasites.

Following the collapse she became confused and started experiencing numbness and tingling in her body.

From there, Lowri ended up giving up work and moving in with her dad in Carmarthen.

She was put on steroids that altered her appearance and, as her life became smaller, she began to feel low until her mental health collapsed.

"This paranoia and psychosis started kicking in… there was severe anxiety, panic attacks," Lowri, who spent six weeks in a neuropsychiatric hospital, said.

"I spiralled a lot," she recalled.

"My family were losing their mind with how things escalated. Friends were coming and seeing me in such a terrible state."

One of those people who visited was Nicola Brown - a friend of 20 years.

Having not seen Lowri for a month, Nicola was left stunned by her deterioration.

"I walked into the room and she was essentially behaving like a child," recalled Nicola.

"Crawling around on the floor, hiding behind a curtain, sitting on her dad's lap as if she was five."

She said when the visit ended Lowri swore at her and told her to never come back.

Lowri later sent her a text message.

"It essentially said, 'Thanks so much for coming to visit. You're going to see me on the news tonight. The police are after me'."

She said it had been a scary and uncertain time.

"I just remember thinking, 'Is this Lowri now? Will we ever see the Lowri we know again?'"

After coming out of hospital, Lowri was still "in a bad way" and moved back in with her dad.

"I didn't feel myself at all, I didn't look myself in the slightest, I didn't want to go out," she said.

From there Lowri completed an art foundation course in Carmarthen, and by 2018 felt strong enough to move back to Cardiff and did an interior design degree.

She eventually returned to work in 2022.

"This is the only case I've seen like this with presentation over many, many years," he said.

He said her case had been discussed by many leading experts in the UK and the US.

"I wouldn't expect to see another case like this during my career - and there'll be many infectious disease consultants across the country who will never see a case like this, that's how rare it is," he said. [...]

Noting that the United States is experiencing its earliest-ever start to the West Nile virus (WNV) season, the Centers for Disease Control and Prevention (CDC) is urging Americans to take precautions against mosquito bites over the Fourth of July holiday weekend.

Along with the early start to the season, the country has seen the most cases of West Nile disease in people by this time of year since 2004. Of the 48 infections reported by 12 states as of June 30, 38 (79%) have caused severe neuroinvasive illness. This is a marked rise from the average 10 cases usually reported to the CDC by June 30.

“This surge is driven by early circulation of the virus, with 23 states reporting West Nile virus activity—also the highest number recorded over the last 10 years,” the statement said.

WNV is the country’s leading cause of mosquito-borne illness, accounting for an average of several thousand infections and about 100 deaths each year. Most infected people have no symptoms, but about 20% develop a fever and symptoms such as headache, body aches, joint pain, vomiting, diarrhea, or a rash.

Less than 1% of infected people experiences severe neurologic disease, including meningitis or encephalitis, which can lead to long-term disability or death. Risk factors for severe disease are older age (60 years and older) and having certain underlying medical conditions.

Arizona reports 32 cases

So far this year, Arizona has reported the most human cases (32), while Texas has logged four and Tennessee two. Arkansas, California, Colorado, Florida, Hawaii, Nebraska, Oklahoma, Pennsylvania, and South Dakota, have each documented one, according to the CDC’s ArboNET surveillance system.

With millions of Americans expected to celebrate the country’s 250th year of independence this weekend, the CDC recommends use of an insect repellent registered with the Environmental Protection Agency. The CDC also advises wearing long, loose-fitting clothing; avoiding being outdoors at night; and using screens on windows and doors or air conditioning to keep mosquitoes out.

"These findings serve as an important reminder that mosquito season is well underway," CDC Medical Epidemiologist Erin Staples, MD, PhD, said in the statement. "As families gather outdoors to celebrate Independence Day, we encourage everyone to enjoy their holiday while taking simple steps to protect themselves and their loved ones from mosquito bites."

Casualties of the Ebola Bundibugyo virus outbreak in Africa continue to mount, with a total of at least 1,354 infections and 401 deaths in the Democratic Republic of the Congo (DRC) and Uganda, as investigators track potential spread to new DRC provinces and Uganda confirms a Marburg infection in a child who died of the virus. Like Ebola, the closely related Marburg virus causes a hemorrhagic fever.

The new totals come after the addition of 26 cases and 22 deaths yesterday in the eastern DRC provinces of Ituri, North Kivu, and South Kivu. Now health authorities are tracing people who may have been exposed to the virus in the previously unaffected neighboring provinces of Tshopo and Haut-Uele.

In the Tshopo case, officials are looking for people who have been exposed to the body of a pregnant woman who died of Ebola in Ituri on June 27 and was transported roughly 186 miles by motorcycle to the city of Kisangani in Tshopo. The journey was undertaken before the woman was known to have had Ebola.

Authorities have apprehended two contacts of Ebola patients who had been isolated for testing in Ituri and had fled to Haut-Uele province, which also borders South Sudan and the Central African Republic. One of the two contacts tested positive for Ebola, while the other was awaiting a confirmatory test. They were returned to Ituri while healthcare teams trace anyone they may have encountered in Haut-Uele.

No additional Marburg cases in Uganda

While no Ebola infections have been confirmed in South Sudan, humanitarian groups are working to shore up health-system preparedness because of the country’s transient populations and permeable borders with the DRC.

Today, a Relief Web report said that the International Medical Corps is supporting 80 facilities in which workers have conducted more than 53,200 screenings and treated 314 patients, including 110 with confirmed Ebola.

Both the DRC and Uganda declared the outbreak on May 15, but it is believed to have begun much earlier.

Today, Ugandan health officials confirmed a single case of Marburg in a 1.5-year-old child who died of the virus in Kyegegwa district in the western part of the country, Reuters reports. No contacts of the child have experienced symptoms, and no other cases have been identified. As is true for the Bundibugyo strain of Ebola virus, there is no vaccine to prevent Marburg infection.

The US embassy in Uganda has issued an alert over reports of a potential Marburg case in the country’s western region.

“The US Embassy is aware there are reports of a potential case of Marburg Virus Disease, a viral haemorrhagic fever, in western Uganda,” it said in the advisory, which was published on Monday.

As of Tuesday, Uganda’s health ministry had yet to release any information on the suspected outbreak, which remains unconfirmed.

Uganda has extensive experience with dealing with outbreaks of haemorrhagic fevers and last reported a Marburg outbreak in 2017, when there were four cases and three deaths.

The country has previously sought to downplay the impact of haemorrhagic fever outbreaks in effort to protect its burgeoning tourism industry.

A message on the health ministry’s homepage, just beneath a link to its dashboard tracking the spread of Ebola, reads: “Ministry of Health is in control. No need for panic. Uganda is safe!” [...]