Tag Archives: plague

The Plague Returns: Should You Be Concerned?

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Earlier this week, health officials in Arizona reported a death due to pneumonia, specifically that Plague – responsible for decimating nearly half of Europe’s population during the 14th century, historically known as the Black Death.

At the same time, the US is grappling with its largest measles outbreak in 20 years, with over 1,300 cases confirmed according to the CDC.

The resurgence of numerous infectious diseases, once thought to be under control, raises important questions: how common is the reappearance of disease?

We consulted Professor Paul Hunter, a medical expert from the Norwich School of Medicine at UEA. He discusses the reasons for this resurgence of diseases, the alarming truth behind their persistence, and what it would take for society to face another catastrophic outbreak akin to the Black Death.

How normal is it for infectious diseases believed to be eradicated to return?

The real question is whether they ever truly disappeared. Many infectious diseases that were once common are still circulating and may resurge with vigor. On a global scale, we typically observe one or two significant outbreaks or reappearances annually.

For many of the classic infectious diseases that seem to be re-emerging, they likely never vanished entirely; rather, their reoccurrences can be more localized. For instance, cholera might flare up in areas that haven’t experienced outbreaks for decades.

Is it feasible to eradicate a disease completely?

In theory, it might be possible to eradicate certain diseases. Initially, I believed polio could be eradicated, but it doesn’t seem likely now. Generally, we don’t anticipate the complete eradication of most infectious diseases. While global control and management of infections is achievable, complete eradication remains nearly impossible.

In the case of polio, the vaccine was highly effective, public health initiatives were strong, and it was relatively easy to diagnose outbreaks swiftly.

Today’s landscape presents unique challenges. Many infectious agents can spread before individuals exhibit any symptoms. As demonstrated during the Covid pandemic, it’s nearly impossible to eradicate a disease when transmission is often undetectable.

Compounding this is the difficulty in managing outbreaks in conflict zones. While a vaccine for Ebola exists, controlling outbreaks in the Democratic Republic of the Congo remains a challenge.

What triggers the return of diseases?

The primary factor is viral evolution. This is evident with the flu virus, which adapts over time. Occasionally, significant evolutionary changes lead to faster-spreading variants known as “escaped mutations,” as observed with various Covid variants.

Another factor is how diseases can be transmitted to humans. Some illnesses, like the plague, persist in nature. The “Silvatic plague” infects rodents, and environmental changes can lead to increased human contact with these animals.

In the US, sporadic plague cases have been noted among hunters or individuals who come close to rodent populations.

A major plague outbreak occurred in Madagascar decades ago, largely driven by environmental degradation that put humans in closer contact with infected rodents.

Climate change is also reshaping the distribution of many infectious diseases, introducing them to areas where they were previously uncommon. For instance, small outbreaks of dengue fever are beginning to appear along the Mediterranean coast, a region typically not associated with this disease due to warming temperatures.

A significant contributor to the resurgence of diseases is the decline in vaccination rates. This is particularly evident with the current measles situation in the UK.

I contracted measles as a child, and most people from my generation did as well. However, younger individuals may never have seen a case, leading to reduced urgency surrounding vaccination. When vaccination rates drop, diseases like measles can re-emerge.

What factors contribute to the resurgence of diseases like the bubonic plague?

In essence, there is little difference between modern and historical bacterial infections. The plague remains as virulent as ever, but due to antibiotics, it can be treated in ways that were not available in the Middle Ages.

While the plague remains a serious threat, proper treatment means that few should die from it today, even if infected.

Societal collapse occurs when these diseases become uncontrollable. This phenomenon has been observed in Madagascar, where conflicts, environmental degradation, and economic downturns led to closer interactions between humans and animals, facilitating disease transmission.

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Which infectious disease poses the greatest risk of resurfacing?

Cholera poses a significant threat in certain regions, particularly in Ukraine and Gaza. While cholera is not currently present in either conflict zone, should it appear, it could spread rapidly and result in devastating fatalities.

Currently, there is a cholera vaccine shortage, partly due to the shift in focus toward Covid vaccine production and pandemic disruptions, as well as the recent uptick in cholera infections.

Typically, there would be ample reserves of cholera vaccines, but stockpiles are now depleted, with any upcoming supply already allocated to high-risk countries.

Perhaps the most dangerous threat is the potential for another major flu pandemic, similar to the Spanish flu of 1918. While Covid primarily affected older individuals, the Spanish flu led to agonizing deaths, with severe pulmonary complications. It could cause higher mortality rates than many other infectious diseases.

Another concern is international travel, as evidenced by Covid. What other risks can come from overseas?

Travel poses significant risks, especially from antibiotic-resistant organisms, which some might consider emerging infectious diseases. These viruses have existed for some time but have now developed resistance to multiple treatment options.

Much of this issue arises from practices such as sex tourism, leading to the spread of drug-resistant sexually transmitted infections.

Medical tourism also contributes to this risk, as individuals traveling for affordable cosmetic or dental procedures might inadvertently foster the spread of these resistant strains.

Listen to our complete interview about instant geniuses.

About our expert

Professor Paul Hunter specializes in the epidemiology of emerging infectious diseases at the Norwich School of Medicine, University of East Anglia (UEA). His research focuses on diseases influenced by environmental factors and has been published in journals such as PLOS 1, Lancet Public Health, and British Medical Journal (BMJ).

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Source: www.sciencefocus.com

Northern Europe may have been decimated by the plague 5,000 years ago

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The culture that built Stonehenge suffered a mysterious population decline

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The European Neolithic culture that produced megaliths like Stonehenge experienced a major decline about 5,400 years ago, and the best evidence now is that this was due to plague.

Sequencing of ancient DNA from 108 people living in northern Europe at the time revealed that the plague bacillus Plague Yersinia pestis The condition was present in 18 of those who died.

“We think the plague killed them.” Frederick Siersholm At the University of Copenhagen, Denmark.

About 5,400 years ago, The population of Europe has declined sharplyWhy this happens, especially in the northern regions, has long been a mystery.

Ancient DNA studies over the past decade have revealed that local populations never fully recovered from the Neolithic decline, but were largely replaced by other peoples who migrated from the Eurasian steppes: in Britain, for example, by about 4,000 years ago, less than 10% of the population descended from the people who built Stonehenge.

Studies of ancient people have also uncovered some instances of the presence of the plague bacterium, suggesting an explanation that the plague may have wiped out the population of Europe, allowing steppe peoples to migrate with little resistance.

But not everyone agreed, arguing that occasional sporadic outbreaks were to be expected and not evidence of a major pandemic. Ben Krauss Keora The findings were published in 2021 at Kiel University in Germany. Plague Yersinia pestis He and his colleagues write that their DNA shows that the virus cannot survive in fleas, making it unlikely to cause a pandemic: Bubonic plague, which killed people in the Black Death during the Middle Ages, is often transmitted by the bite of an infected flea.

So Sirsholm and his colleagues set out to find more evidence of the plague pandemic. The 108 people whose DNA his team sequenced were buried in nine graves in Sweden and Denmark. Most of them died between 5,200 and 4,900 years ago, and they spanned several generations of four families.

Over the course of just a few generations, the plague appears to have spread three separate times, the last of which may have been caused by a genetically modified strain that was far more deadly.

“This virus is present in many people,” Searsholm said, “and it's all the same version. That's exactly what you expect when something spreads quickly.”

Plague DNA was found primarily in teeth, indicating that the bacteria entered the bloodstream and caused severe illness and possibly death, he said. In some cases, close relatives were infected, suggesting person-to-person transmission.

The research team suggests that this may be a result of: Plague Yersinia pestis It is a type of disease called pneumonic plague, which infects the lungs and spreads through droplets. Human lice can cause bubonic plagueNot only fleas but also the plague bacteria can be spread this way.

“Of course, it's worth noting that all of these people were properly buried,” says Searsholm, meaning society had not collapsed at this point. “If there really was an epidemic, we're only just seeing the beginning.”

The megalithic tomb appears to have been abandoned for several centuries after about 4900 years ago, but the 10 sequenced individuals were buried much later, mostly between 4100 and 3000 years ago. These individuals were from the steppe region and are unrelated to the people who built the tomb.

“It's a 100 percent complete turnover,” says Searsholm, “5,000 years ago, these Neolithic people disappeared, and now we have evidence that plague was rampant and widespread at exactly the same time.”

While the researchers don't claim their findings are conclusive, Searsholm says they do support the argument that plague caused the Neolithic decline.

“It's pretty clear that this virus can infect humans and can, for example, kill an entire family.”

Klaus Kiora acknowledges that the discovery shows that the plague was widespread in this particular place and time: “Previous explanations need to be somewhat revised and we can't just talk about isolated cases,” he says.

But there's no evidence of high prevalence in other areas, he says, and he thinks normal burials indicate there were no deadly epidemics. Yersinia The infection was like a long-term chronic disease.”

Sirsholm and his team plan to search for more evidence across Europe in the coming days, but the only way to know for sure how deadly the engineered strain was would be to resurrect it, which he says is far too risky to attempt.

“I think this paper will convince many of our colleagues who have been skeptical of our previous work,” he said. Nicholas Raskovin In 2018, a team of researchers from the Pasteur Institute in Paris discovered the plague bacillus in two Neolithic individuals and proposed that the decline of the Neolithic period was due to the plague.

topic:

  • Archaeology/
  • Infection

Source: www.newscientist.com

Has the bubonic plague, cholera, and measles made a comeback? Is there cause for concern?

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In the first two months of 2024, measles outbreaks in the US and UK, a global cholera vaccine shortage, and a case of bubonic plague from an infected cat in Oregon have sparked concern. The resurgence of seemingly eradicated diseases raises questions about their return.

To shed light on the frequency of disease resurgences, we spoke with Paul Hunter, Professor of Medicine at UEA Norwich Medical School. Paul uncovers the reasons behind the resurgence, identifies potential epicenters, and discusses preventive measures to avert another Black Death.

How common is it for an infection that you thought had gone away to come back?

Many infectious diseases that were once prevalent and endemic continue to resurface with varying intensities. Globally, there is an average emergence or re-emergence of one or two significant diseases per year.

The resurgence of classic infections often occurs at a localized level. For instance, an area that was previously unaffected by cholera may suddenly witness an outbreak after decades.

Is it possible to completely wipe out disease from the earth?

While diseases like smallpox have been eradicated, the prospect of eliminating most infectious diseases remains elusive. Global spread and early transmission of infections make eradication improbable.

The success of smallpox eradication was attributed to an effective vaccine with clear diagnostic criteria for detection. However, challenges persist, especially with diseases spreading before symptoms manifest, as evident from the difficulties in eradicating COVID-19.

Moreover, conflict zones hinder disease control efforts, as seen during the Ebola outbreak in the Democratic Republic of the Congo.

What are the main ways the disease can return?

Viruses can evolve, leading to rapid spread and new strains, as seen with the emergence of new coronavirus variants. Environmental factors can also facilitate disease transmission, as exemplified by sylvatic plague spread through rodents.

Climate change plays a significant role in altering disease distribution, with dengue fever outbreaks appearing in unexpected regions due to warming climates.

Declining vaccine availability and uptake further contribute to disease resurgence, highlighting the importance of vaccination in disease prevention.

What does it take for a resurgent disease like bubonic plague to get out of control?

Bacterial infections like plague have the potential to wreak havoc, but antibiotics offer effective treatment. When diseases escalate, societal collapse often exacerbates the situation, increasing disease transmission and mortality.

Conflicts, environmental degradation, and economic crises create conditions conducive to disease spread, as observed in outbreaks like the one in Madagascar.

Which infectious disease would be the worst if there was a resurgence?

Cholera poses a significant threat, especially in conflict zones like Ukraine and Gaza. Shortages in cholera vaccines and increasing infection rates heighten concerns for rapid spread and high mortality rates.

An influenza pandemic akin to the 1917 Spanish flu remains a grave concern, given the potential for widespread fatalities, especially among younger individuals.

Another risk, of course, is international travel, as we’ve seen with coronavirus. What kind of unnecessary souvenirs can I bring back from abroad?

Antibiotic-resistant bacteria pose a major threat to international travelers, fueled by factors like sex and medical tourism. These infections, resistant to multiple drugs, raise concerns about global disease transmission.

Unsafe medical procedures during medical tourism contribute to the spread of drug-resistant infections, emphasizing the need for vigilant healthcare practices abroad.

Read the full interview with Instant Genius.

About our experts

Professor Paul Hunter, a renowned epidemiologist at UEA Norwich Medical School, focuses on emerging infectious diseases linked to environmental factors. His research published in prominent medical journals underscores the importance of disease surveillance and prevention.

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Source: www.sciencefocus.com

Severe Water Shortages Plague Mexico City’s 21 Million Residents

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The ancient relationship between Mexico City and water dates back to the city’s origins. Situated on a former lakebed that was drained after the Spanish conquest in the 16th century, the city now relies on underground aquifers and a network of canals, dams, and reservoirs from the Kutsamara water system for its main water supply.

Approximately 70% of the city’s water comes from underground sources, with the remaining 30% supplied by the Cuzamara system to the Mexico City metropolitan area and the Toluca Valley. However, increasing urbanization and overuse of aquifers have led to land subsidence, causing the city to sink at a rate of about 20 inches per year since 1950 due to continued groundwater extraction.

Despite efforts to repair and upgrade aging infrastructure, Mexico City’s water system struggles to keep pace with the demands of a rapidly growing population. Climate change further exacerbates the water crisis, with persistent drought and rising temperatures leading to decreased precipitation and limited water replenishment for aquifers and dams.

This water scarcity crisis has sparked protests and unrest among residents, with many areas facing severe water shortages. Efforts to conserve water and prioritize its usage have been urged by local authorities, as communities like Iztapalapa struggle to cope with limited water access.

For residents like Hernández Villa, conserving water has become a daily challenge, with measures like reducing laundry frequency and bathing in containers to stretch their limited water supply. The urgent need for sustainable water management and infrastructure upgrades is evident, as Mexico City grapples with a worsening water crisis.

Dennis Chou reported from New York City and Alvinson Linares from Mexico City.

Source: www.nbcnews.com