The portion of our nervous systems responsible for the “fight or flight” response can shape the severity of potentially deadly Clostridioides difficile infections, new research from the School of Medicine reveals in Cell Reports Medicine.
The findings suggest that doctors may be able to save patients from the infections – a plague for hospitals and nursing homes – by using drugs to quiet the hyperactive nervous system response, the researchers say.
“Compared to how much we know about immune system influences in C. difficile infections, the field is just scratching the surface in understanding neuronal contributions to disease,” said researcher William A. Petri Jr., MD, PhD, of UVA Health’s Division of Infectious Diseases and International Health. “Newly identifying components of the nervous system that worsen inflammation will allow us to determine potential therapeutic targets and biomarkers for patients at risk of severe disease.”
C. difficile, is a perpetual burden for healthcare facilities. Extensive antibiotic use, particularly among patients who are hospitalised or in nursing care, can allow it to establish dangerous infections. Further, patients who make it through the severe diarrhoea, nausea, fever and colitis C. difficile can cause are not necessarily in the clear: One in six will develop another C. diff infection within eight weeks, according to the federal Centers for Disease Control and Prevention.
The new UVA research reveals the critical role the nervous system plays in severe C. difficile infections. The researchers found that the “sympathetic” nervous system – the branch that responds to dangerous situations – can be a key driver of serious C. diff.
Normally, our “fight or flight” response is helpful for avoiding danger. It helps us respond quickly, improves our eyesight, boosts our strength. It also can stimulate our immune system and help us recover from injury. But in C. difficile cases, the nervous system can have a hyperactive response that becomes part of the problem, and UVA’s new research explains why.
“Neurons are the first responders that coordinate defences against toxic attacks. Sometimes those responders don’t recruit the right size and kind of artillery and that can make things worse,” said researcher David Tyus, a neuroscience graduate student at UVA. “Interestingly, the receptor we identified as important in C. difficile infection [the alpha 2 adrenergic receptor] has also been linked to irritable bowel syndrome. I’m curious to know if there could be a unifying underlying mechanism between the two disease contexts.”
Promisingly, the researchers found that targeting the receptor in lab mice reduced intestinal inflammation and decreased C. difficile severity and mortality. That suggests that, with further research, doctors may be able to take a similar tact to better treat severe C. diff infections in patients. For example, they may be able to surgically remove a portion of nerves in the gut, or they may be able to develop medicines to target the alpha 2 receptor – as Petri and Tyus are attempting to do.
“Our next step is to determine which cells with the alpha 2 receptor are receiving signals from the sympathetic nervous system and play a role in C. difficile-mediated disease,” Petri said. “We are very excited to think about how our findings translate to clinic and how the sympathetic nervous system might play a role in recurrent infection. I hope that this study sets the foundation for future findings of how neurons affect the course of C. difficile infection outcomes.”
Hepatitis C virus. Credit: Scientific Animations CC4.0
Around 58 million people suffer from chronic inflammation caused by the hepatitis C virus, and 300 000 people die from the disease every year. So far, no treatment has successfully managed to reduce the global prevalence of hepatitis C, prompting scientists to start looking for a vaccine. But limited knowledge of the protein complex that enables the virus to infect the cells has made this difficult.
A new study by a cross-disciplinary research team at the University of Copenhagen is about to change that. It is out now in the journal Nature.
“We are the first ever to identify the protein complex at the surface of the hepatitis C virus that enables it to bind to our cells,” says Associate Professor Jannick Prentø.
“This knowledge of the structure of the protein complex will enable us to design vaccine candidates that can prevent the virus from infecting the cells,” says Postdoc Elias Augestad.
The protein complex helps the virus bind to the cells. In the corona virus, it is a so-called spike protein with the well-known spikes. In the hepatitis C virus, the structure is different, but the function of the protein complex is the same.
Paves the way for vaccine development
The study can be considered a blueprint for HCV vaccine development. Scientists hope to be able to use the new knowledge to develop a vaccine which will make the immune system produce antibodies that bind effectively to the surface of the hepatitis C virus and thus render it harmless.
“Expressing and cleaning up the protein complex is extremely difficult, which is why it has not been done before. The structure of these proteins on the surface of the hepatitis C virus makes them extremely vulnerable. Researchers did not know what they were dealing with, and therefore, whenever someone tried to reproduce these protein structures in the lab they would fall apart before they could get a chance to study them,” says Associate Professor Jannick Prentø.
“But we managed to describe their structure, and this has enabled us to reproduce these protein complexes outside the cell and study them closely,” says Associate Professor Pontus Gourdon.
The African Centre for Disease Control and World Health Organization have raised the alarm following a drastic uptick in mpox cases. This surge is being driven by a new strain of the virus. Elri Voigt reports about what we know so far and potential implications for South Africa.
Mpox, a viral illness first identified in Africa in 1970, made headlines in 2022 when it spread across the globe for the first time. Since then, the outbreak has evolved, with multiple strains of the virus circulating in different countries. A new strain, known as clade Ib, first discovered in the Democratic of the Republic of Congo (DRC), is responsible for much of the most recent surge in mpox cases.
These recent developments are complex, and the situation is likely to change. This was the common theme of a special session on the mpox outbreak during the World Health Organization (WHO) Regional Committee for Africa meeting at the end of August. This session took place two weeks after the WHO declared the outbreak to be a Public Health Emergency of International Concern.
“We don’t have one outbreak. We have multiple outbreaks in one,” Dr Jean Kaseya, the Director General of the African Centre for Disease Control (CDC) remarked.
These outbreaks are caused by different clades of the mpox virus. Clades are a classification system based on the genetic similarities between different strains of a virus, explained Professor Tulio de Oliveira, Director of the Centre for Epidemic Response and Innovation (CERI) at Stellenbosch University (SU). “So, what it means is that when we see a genetic change [in a virus] that’s really visible and that may have impacted it, normally we call it a different clade or genotype or variant,” he said.
This is similar to classifying different strains of SARS-CoV-2 as variants, Dr Duduzile Ndwandwe, a molecular biologist working for Cochrane South Africa, an intramural research unit within the South African Medical Research Council, told Spotlight.
She explained that the different mpox clades and sub-clades have mutated so they have genetic differences but still fall under the umbrella of mpox.
“In a nutshell…it’s just talking about the differences in the genome sequence of the virus, how many mutations [it has] or how big the mutations are in that virus’s strain of mpox,” she said.
‘Jump in evolution’
Dr Aida Sivro, senior scientist at the Centre for the AIDS programme of Research in South Africa (CAPRISA), in 2022 told Spotlight that there are two clades of the mpox virus, which were then referred to as the Central African Clade (clade I) and the West African Clade (clade II).
Since then, clade I went through a big jump in evolution and a sub-clade emerged in the DRC, now called clade Ib, De Oliveira told Spotlight. The previous outbreak in 2022 was mostly driven by another sub-clade called clade IIb.
To further complicate matters, there’s a third strain of the virus also circulating – clade Ia.
At the moment, the DRC accounts for about 90% of mpox cases in the African Region, according to Dr Fiona Braka, the Emergency Response Manager for WHO’s AFRO region. She explained that right now the situation is not fully understood because a lack of diagnostics and testing capabilities is limiting understanding of the true burden of disease.
What we do know, she said, is that there are two distinct outbreaks in the DRC. Based on the information currently available, clade Ia is circulating in regions in the country where mpox is considered endemic and affecting mostly children. While clade Ib is spreading mostly among adults in the eastern provinces of South Kivu and North Kivu.
The clade Ib strain has since spread from the DRC to neighbouring countries Burundi, Rwanda, Uganda and Kenya, according to Braka. Sweden and Thailand have also identified one case each.
As of 1 September, the WHO reported that there have been 3 751 confirmed cases of mpox and 32 deaths across 14 countries in African in 2024 alone. But there are many more suspected cases of mpox that have not been tested.
Implications for South Africa
De Oliveira said at this point, South Africa shouldn’t be overly concerned about mpox, but it should be alert. The best way to do this is to make sure the public know what the symptoms are so they can present for diagnosis and treatment if they suspect they have the virus.
In a similar vein, Ndwandwe said the public shouldn’t panic, but we as a country need to remain vigilant. She added that because clade Ib is spreading on the African continent, there is a risk of it spreading to South Africa through cross-border travel, making it a public health concern.
This year, 24 cases of mpox have been reported in South Africa. Three people have died, while 19 have recovered. Two people are still considered to have active disease, with the most recent case identified in early August.
But this doesn’t necessarily mean there aren’t more cases of mpox in the country. “What we do suspect is that we may have milder cases that are actually not reported,” Nevashan Govender, the operation manager of the Emergency Operations Center at the National Institute for Communicable Diseases (NICD) told Spotlight.
He said so far, all the cases in the country have been caused by clade IIb and no cases of clade Ib have been identified.
A polymerase-chain-reaction (PCR) test is the gold standard test used to determine whether someone has mpox. But genome sequencing would need to be done to identify what clade they have.
Lots of unknowns around new strain
At the moment, there are a lot of unknowns around clade Ib.
What is of concern, according to Braka is the severity of disease seen especially in people who are immunocompromised and in pregnant women and children. Ndwandwe added to this and said there is a concern that clade Ib has higher fatality rates than clade IIb.
De Oliveira cautioned against jumping to conclusions about the severity of this new clade without sufficient data. He said we don’t know for sure yet if clade Ib is causing more severe disease than IIb. What we do know from mpox in general, he said, is that when someone is immunocompromised in some way, they tend to develop more severe symptoms.
Govender echoed De Oliveira’s caution that we don’t yet know enough about clade Ib to say definitively if it is for example more transmissible than other clades
“It’s not to say that it isn’t [more transmissible], but there is just not a lot of evidence stating that it is absolutely true…There’s a lot of knowledge and information gaps,” he said.
The NICD in a recent update also stressed that there are a lot of unknowns about this new strain. It added: “South Africa continues to prioritise enhanced surveillance and raising awareness for mpox.”
The state of vaccines and treatment for mpox
Spotlight reported previously that the smallpox vaccine, which hasn’t been routinely administered in South Africa since the 1980s when smallpox was eradicated, is thought to offer some degree of protection against mpox. However, it’s difficult to predict just how much protection the smallpox vaccine would provide, Sirvo told Spotlight for that previous article.
There are currently three vaccines against mpox that have been approved in some countries, a spokesperson from the vaccine alliance Gavi told Spotlight. These are LC16m8, JYNNEOS and ACAM2000.
LC16m8 is a third-generation small pox vaccine manufactured by KM Biologics. According to WHO, from 2022 it had mainly been used in Japan.
The JYNNEOS vaccine is a third-generation smallpox vaccine, manufactured by Bavarian Nordic, Ndwandwe said, and it was used during the outbreak in 2022. She added that this vaccine is considered the preferred option due to its safety profile and targeted protection against mpox.
ACAM2000 is a second-generation vaccine for smallpox and manufactured by Emergent BioSolutions. But it was only approved by the FDA for use in those at high risk for mpox at the end of August this year. It was not widely used during the 2022 outbreak but was available in some places under a compassionate use protocol (a means of providing medicines or vaccines that have not yet been registered).
In 2022, the Centre for Disease Control (CDC) recommended that JYNNEOS be used as the primary vaccine against mpox because it was associated with fewer side effects than ACAM2000.
While these vaccines exist, it doesn’t mean everyone can access them easily. Countries on the African continent have so far relied on vaccine donations facilitated by the WHO, with an initial 10 000 doses expected to arrive in Africa sometime this month.
Vaccine manufacturers KM Biologics and Bavarian Nordic have submitted proposals to the WHO for emergency use listing (EUL), according to WHO Director-General Dr Tedros Adhanom Ghebreyesus. He added this will allow UNICEF and the vaccine alliance GAVI to buy the vaccines to supply to countries that haven’t issued their own national regulatory approval yet.
The treatment options for mpox are also limited. According to this WHO factsheet on mpox, some antivirals have received emergency use authorisation in some countries and are being evaluated in clinical trials. However, so far there is no proven effective antiviral treatment for mpox.
Tecovirimat, which was approved to treat smallpox, is one of these antivirals being evaluated. According to the CDC, studies in animals have shown the antiviral might help treat mpox but it is still considered an investigational drug for mpox. The drug has been used in some cases of severe mpox.
When asked about this, Ndwandwe agreed more research needs to be conducted to fully understand the evidence around using Tecovirimat. “But what we know now is that the fact that it was authorised for compassionate use, there is some benefit to using that treatment, given that there isn’t any other [treatment,” she said.
Mpox vaccine and treatment availability in South Africa
According to De Oliveira, a small batch of vaccines against mpox and an antiviral drug were made available to South Africa through donations during the outbreak earlier this year.
But the country would need more vaccines if cases increase to protect those at risk for severe disease.
At the moment, South Africa does not have access to any mpox vaccines and has asked for a donation of 40 000 vaccine doses, Foster Mohale, spokesperson for the health department told Spotlight. The country has requested the JYNNEOS vaccine, based on the recommendation by the National Advisory Group on Immunisation.
He added that South Africa’s request to its international partners and the WHO is ongoing support with access to tecovirimat should the need increase. He also requested the WHO’s assistance in procuring the 40 000 vaccine doses to vaccinate high-risk groups if mpox cases increase.
When asked if the department will be entirely reliant on donations of mpox vaccines or would seek to procure its own if cases increase, Mohale said it depends. “South Africa has been in communication with the vaccine manufacturer, Bavarian Nordic, and will consider procurement if needed,” he added.
Because there is a shortage of mpox vaccines and treatment and uncertainty about the sustainability of donated supplies, Ndwandwe said: “Our best defence at this point in time is to prevent [the spread of mpox cases] as much as possible and detect the cases as they start, early on.”
Symptoms of mpox
Govender said the NICD is urging people not to panic but to stay informed on the signs and symptoms of mpox using some of the accurate information available from either the National Department of Health or the NICD.
“The first line of defence for any public health emergency and outbreak comes from when people take initiative to protect themselves,” he said.
Mpox, which is spread by close contact, either household or sexual contact, with someone who has the virus, could initially manifest in flu-like symptoms or the characteristic mpox rash. These include a fever, sore throat, muscle aches, headaches and swollen lymph nodes, according to the WHO factsheet on mpox. The rash starts flat and then becomes a blister filled with fluid, which eventually dries and falls off. The rash can occur on someone’s palms or soles of their feet, face, mouth and throat and sometimes the genital areas.
Children, pregnant women and those who are immunocompromised are most at risk for developing severe disease or dying, the factsheet stated. This includes people living with HIV whose viral load is not well controlled.
Mpox is a virus and as with all viral infections it’s the immune system that fights it off, Ndwandwe explained. However, if someone is immunocompromised, so has a weakened immune system, there is a greater chance that the mpox virus will overtake their immune system and cause severe disease.
This is one of the reasons why we would be concerned about the disease in South Africa, Professor Helen Rees, the Co-Chair of the Incident Management Team (IMT) on mpox, previously told eNCA.
“We have many people living with HIV in the country, many of whom are on antiretroviral therapy, their immune system is good. But we have many others, who don’t know what their status is and might be vulnerable to severe mpox,” she said.
Researchers have discovered that what time of the night a malaria-bearing mosquito bites may have significant effect on the subsequent infection’s severity.
When mice are infected in the middle of the night with the parasites causing cerebral malaria, the symptoms of the disease are less severe than for those inflected during the day, and the spread of the parasites within the hosts is more limited, research teams from McGill University, the Douglas Research Centre and the Research Institute of the McGill University Health Centre have discovered.
Malaria is a mosquito-borne infectious disease that affects hundreds of millions of people worldwide. It kills more than half a million people each year, most of them children. Cerebral malaria is the deadliest form of the disease.
The researchers’ findings, published in the journals iScience and ImmunoHorizons, have the potential to lead to new treatment practices based on aligning medication with our circadian rhythms.
How circadian rhythms of host and parasite interact
Circadian rhythms are defined as physiological and behavioral oscillations with cycles of approximately 24 hours, matching the Earth’s rotation, that persist in the absence of environmental timing cues. These rhythms are regulated by a master clock in the brain, as well as by clocks located in most other organs and cell types throughout the organism.
“We explored how the circadian rhythms of both the host and the malaria parasite interact to affect the severity of the disease and the host’s ability to fight off the parasite,” said Priscilla Carvalho Cabral, a recent McGill PhD graduate who carried out the experiments described in two recent studies on the subject.
Nicolas Cermakian, Director of the Laboratory of Molecular Chronobiology, and the corresponding author of the two studies, noted, “The difference in a host’s response to infection depending on the time of day suggests that their circadian rhythms could be influencing the progression of the disease. How such immune clocks impact malaria has not been looked at before.”
An important advance in knowledge
In parasites and their animal hosts, as well as in most living organisms, many bodily functions are under circadian control. It is known, for instance, that the replication of malaria parasites inside the red blood cells of a host follows a daily rhythm. Previous work from the same team has already shown that another serious parasitic disease, leishmaniasis, is affected by host clocks: the time of infection influences the replication of the parasite as well as the immune response to it. In the new studies, the same was found to be true for cerebral malaria.
“Our results represent an important advance in knowledge since many of the mechanisms driving the rhythms in susceptibility to diseases, especially parasitic diseases, remain largely unknown,” says Martin Olivier, Director of the Laboratory for the Study of Host-Parasite Interaction, a professor in McGill’s Department of Microbiology and Immunology and co-author of the two studies.
When the NKp46 receptor of the ILCs is blocked (right), the lupus nephritis recedes. Blue: cell nuclei. Credit: Charité | Frauke Schreiber
A Berlin-led research team has uncovered critical regulators of severe kidney damage in patients with the autoimmune disorder lupus. A small, specialised population of immune cells – called innate lymphoid cells (ILCs) – trigger an avalanche of effects that cause harmful kidney inflammation, also known as lupus nephritis.
The research, published this week in Nature, upends conventional wisdom that autoantibodies are primarily responsible for lupus nephritis.
“While autoantibodies are required for tissue damage, they are by themselves not sufficient. Our work reveals that ILCs are required to amplify the organ damage,” says Dr Masatoshi Kanda, a senior paper author who was a Humboldt Fellow at Max Delbrück Center and is now at the Department of Rheumatology and Clinical Immunology, Sapporo Medical University in Japan.
Lupus, or systemic lupus erythematosus, is most often diagnosed between the ages of 15 and 45. Symptoms can range from mild to severe. But what causes kidney damage in some patients – some to the point of requiring dialysis – has been unclear.
“The role of ILCs in lupus or lupus nephritis was entirely unknown,” says Professor Antigoni Triantafyllopoulou, a senior paper author at the German Rheumatology Research Center (DRFZ), an institute of the Leibniz Association, and at the Department of Rheumatology and Clinical Immunology at Charité – Universitätsmedizin Berlin. “We have now identified most of the circuit controlled by ILCs by looking at the whole kidney at single-cell resolution.”
Unusual immune cells
ILCs are a small group of immune cells that – unlike most other immune cells that circulate throughout the body – live in a specific tissue or organ.
“They are in the tissue all the time, from the time of embryonic development, which makes them very different from other immune cells,” says Professor Andreas Diefenbach, a senior paper author and director of the Institute of Microbiology, Infectious Diseases and Immunology at Charité – Universitätsmedizin Berlin.
Diefenbach’s lab was among those that discovered ILCs in the mid-2000s. Most of his research is focused on ILCs in the gut and how they modify tissue function. In this study, Triantafyllopoulou and Kanda teamed up with his group and Dr Mir-Farzin Mashreghi at the DRFZ to find out whether ILCs were present in the kidney and what role they might play in lupus nephritis.
The whole single-cell picture
To unravel this mystery, the team turned to single-cell RNA sequencing, which identifies genes that are active, or “switched on,” in individual cells and helps researchers understand the cell’s identity and function.
Kanda, a rheumatologist who was studying bioinformatics in Professor Norbert Hübner’s lab at the Max Delbrück Center at the time, developed a specialized protocol for single-cell RNA sequencing of mouse and human kidneys. “Masatoshi’s protocol was very good at pulling out and preserving multiple types of kidney cells, which gave us a much more complete overview of how lupus affects the whole kidney,” explains Triantafyllopoulou. The team sequenced nearly 100 000 individual kidney and immune cells of various types and functions.
The key receptor
Through experiments in mice, the team learned that a subgroup of ILCs with a receptor called NKp46 must be present and activated to cause lupus nephritis. When NKp46 is activated, this subgroup of cells ramped up production of a protein called GM-CSF, which stimulates invading macrophages to multiply. In the kidney, a flood of incoming macrophages caused severe tissue damage and fibrosis.
“These ILCs are really amplifiers in this system,” Diefenbach says. “They are small in population, but they seem to fertilise the whole process.”
When the team blocked NKp46 with antibodies or the receptor was genetically removed, kidney tissue damage was minimal. They also blocked GM-CSF with similar anti-inflammatory effects.
“Critically, autoantibody levels did not change when NKp46 was inhibited, but kidney tissue damage was reduced, which shows autoantibodies are not directly responsible for kidney inflammation,” Triantafyllopoulou explains.
The team also compared the results to sequencing data from tissue taken from human patients with lupus and found ILCs present, though more work is required to fully understand how to target ILCs in human kidneys. Nevertheless, the insights gained through these detailed studies point to new antibody therapies for patients with severe forms of lupus. The hope is to prevent the need for kidney dialysis in these patients.
The risk was higher for men who were carriers of a gene linked to dementia
Photo by Mari Lezhava on Unsplash
A new study led by investigators from Brigham and Women’s Hospital found that an episode of shingles is associated with about a 20 percent higher long-term risk of subjective cognitive decline. The study’s findings provide additional support for getting the shingles vaccine to decrease risk of developing shingles, according to the researchers. Their results are published in Alzheimer’s Research & Therapy.
“Our findings show long-term implications of shingles and highlight the importance of public health efforts to prevent and promote uptake of the shingles vaccine,” said corresponding author Sharon Curhan, MD, of the Channing Division for Network Medicine at Brigham and Women’s Hospital. “Given the growing number of Americans at risk for this painful and often disabling disease and the availability of a very effective vaccine, shingles vaccination could provide a valuable opportunity to reduce the burden of shingles and possibly reduce the burden of subsequent cognitive decline.”
Shingles, medically known as “herpes zoster,” is a viral infection that often causes a painful rash. Shingles is caused by the varicella zoster virus (VZV), the same virus that causes chickenpox. After a person has chickenpox, the virus stays in their body for the rest of their life. Most of the time, our immune system keeps the virus at bay. Years and even decades later, the virus may reactivate as shingles.
Almost all individuals in the US age 50 years and older have been infected with VZV and are therefore at risk for shingles. There’s a growing body of evidence that herpes viruses, including VZV, can influence cognitive decline. Subjective cognitive decline is an individual’s self-perceived experience of worsening or more frequent confusion or memory loss. It is a form of cognitive impairment and is one of the earliest noticeable symptoms of Alzheimer’s disease and related dementias.
Previous studies of shingles and dementia have been conflicting. Some research indicates that shingles increases the risk of dementia, while others indicate there’s no association or a negative association. In recent studies, the shingles vaccine was associated with a reduced risk of dementia.
To learn more about the link between shingles and cognitive decline, Curhan and her team used data from three large, well-characterized studies of men and women over long periods: The Nurses’ Health Study, the Nurses’ Health Study 2, and the Health Professionals Follow-Up Study. The study included 149,327 participants who completed health status surveys every two years, including questions about shingles episodes and cognitive decline. They compared those who had shingles with those who didn’t.
Curhan designed the study with first author Tian-Shin Yeh, formerly of the Harvard TH Chan School of Public Health. The researchers found that a history of shingles was significantly and independently associated with a higher risk – approximately 20% higher – of subjective cognitive decline in both women and men. That risk was higher among men who were carriers of the gene APOE4, which is linked to cognitive impairment and dementia. That same association wasn’t present in the women.
Researchers don’t know the mechanisms that link the virus to cognitive health, but there are several possible ways it may contribute to cognitive decline. There is growing evidence linking VZV to vascular disease, called VZV vasculopathy, in which the virus causes damage to blood vessels in the brain or body. Curhan’s group previously found that shingles was associated with higher long-term risk of stroke or heart disease.
Other mechanisms that may explain how the virus may lead to cognitive decline include causing inflammation in the brain, directly damaging the nerve and brain cells, and the activation of other herpesviruses.
The limitations of this research include that it was an observational study, information was based on self-report, and included a mostly white, highly educated population. In future studies, the researchers hope to learn more about preventing shingles and its complications.
“We’re evaluating to see if we can identify risk factors that could be modified to help reduce people’s risk of developing shingles,” Curhan said. “We also want to study whether the shingles vaccine can help reduce the risk of adverse health outcomes from shingles, such as cardiovascular disease and cognitive decline.”
WHO Director-General Dr Tedros Adhanom Ghebreyesus has determined that the upsurge of mpox in the Democratic Republic of the Congo (DRC) and a growing number of countries in Africa constitutes a public health emergency of international concern (PHEIC) under the International Health Regulations (2005) (IHR).
Dr Tedros’s declaration came on the advice of an IHR Emergency Committee of independent experts who met earlier in the day to review data presented by experts from WHO and affected countries. The Committee informed the Director-General that it considers the upsurge of mpox to be a PHEIC, with potential to spread further across countries in Africa and possibly outside the continent.
The Director-General will share the report of the Committee’s meeting and, based on the advice of the Committee, issue temporary recommendations to countries.
In declaring the PHEIC, Dr Tedros said, “The emergence of a new clade of mpox, its rapid spread in eastern DRC, and the reporting of cases in several neighbouring countries are very worrying. On top of outbreaks of other mpox clades in DRC and other countries in Africa, it’s clear that a coordinated international response is needed to stop these outbreaks and save lives.”
WHO Regional Director for Africa Dr Matshidiso Moeti said, “Significant efforts are already underway in close collaboration with communities and governments, with our country teams working on the frontlines to help reinforce measures to curb mpox. With the growing spread of the virus, we’re scaling up further through coordinated international action to support countries bring the outbreaks to an end.”
Committee Chair Professor Dimie Ogoina said, “The current upsurge of mpox in parts of Africa, along with the spread of a new sexually transmissible strain of the monkeypox virus, is an emergency, not only for Africa, but for the entire globe. Mpox, originating in Africa, was neglected there, and later caused a global outbreak in 2022. It is time to act decisively to prevent history from repeating itself.”
This PHEIC determination is the second in two years relating to mpox. Caused by an Orthopoxvirus, mpox was first detected in humans in 1970, in the DRC. The disease is considered endemic to countries in central and west Africa.
In July 2022, the multi-country outbreak of mpox was declared a PHEIC as it spread rapidly via sexual contact across a range of countries where the virus had not been seen before. That PHEIC was declared over in May 2023 after there had been a sustained decline in global cases.
Mpox has been reported in the DRC for more than a decade, and the number of cases reported each year has increased steadily over that period. Last year, reported cases increased significantly, and already the number of cases reported so far this year has exceeded last year’s total, with more than 15 600 cases and 537 deaths.
The emergence last year and rapid spread of a new virus strain in DRC, clade 1b, which appears to be spreading mainly through sexual networks, and its detection in countries neighbouring the DRC is especially concerning, and one of the main reasons for the declaration of the PHEIC.
In the past month, over 100 laboratory-confirmed cases of clade 1b have been reported in four countries neighbouring the DRC that have not reported mpox before: Burundi, Kenya, Rwanda and Uganda. Experts believe the true number of cases to be higher as a large proportion of clinically compatible cases have not been tested.
Several outbreaks of different clades of mpox have occurred in different countries, with different modes of transmission and different levels of risk.
The two vaccines currently in use for mpox are recommended by WHO’s Strategic Advisory Group of Experts on Immunization, and are also approved by WHO-listed national regulatory authorities, as well as by individual countries including Nigeria and the DRC.
Last week, the Director-General triggered the process for Emergency Use Listing for mpox vaccines, which will accelerate vaccine access for lower-income countries which have not yet issued their own national regulatory approval. Emergency Use Listing also enables partners including Gavi and UNICEF to procure vaccines for distribution.
WHO is working with countries and vaccine manufacturers on potential vaccine donations, and coordinating with partners through the interim Medical Countermeasures Network to facilitate equitable access to vaccines, therapeutics, diagnostics and other tools.
WHO anticipates an immediate funding requirement of an initial US$ 15 million to support surveillance, preparedness and response activities. A needs assessment is being undertaken across the three levels of the Organization.
To allow for an immediate scale up, WHO has released US$ 1.45 million from the WHO Contingency Fund for Emergencies and may need to release more in the coming days. The Organization appeals to donors to fund the full extent of needs of the mpox response.
Scientists at ADA Forsyth Institute (AFI) have identified a critical factor that may contribute to the spread of hospital-acquired infections (HAIs), shedding light on why these infections are so difficult to combat. Their study reveals that the dangerous multidrug resistant (MDR) pathogen, Klebsiella, thrives under nutrient-deprived polymicrobial community conditions found in hospital environments.
According to the World Health Organization, HAIs pose significant risks to patients, often resulting in prolonged hospital stays, severe health complications, and a 10% mortality rate. One of the well-known challenging aspects of treating HAIs is the pathogens’ MDR. In a recent study published in Microbiome, AFI scientists discovered that Klebsiella colonising a healthy person not only have natural MDR capability, but also dominate the bacterial community when starved of nutrients.
“Our research demonstrated that Klebsiella can outcompete other microorganisms in its community when deprived of nutrients,” said Batbileg Bor, PhD, associate professor at AFI and principal investigator of the study. “We analysed samples of saliva and nasal fluids to observe Klebsiella‘s response to starvation conditions. Remarkably, in such conditions, Klebsiella rapidly proliferates, dominating the entire microbial community as all other bacteria die off.”
Starvation environments
Klebsiella is one of the top three pathogens responsible for HAIs, including pneumonia and irritable bowel disease. As colonising opportunistic pathogens, they naturally inhabit the oral and nasal cavities of healthy individuals but can become pathogenic under certain conditions. “Hospital environments provide ideal conditions for Klebsiella to spread,” explained Dr Bor. “Nasal or saliva droplets on hospital surfaces, sink drains, and the mouths and throats of patients on ventilators, are all starvation environments.”
Dr Bor further elaborated, “When a patient is placed on a ventilator, they stop receiving food by mouth, causing the bacteria in their mouth to be deprived of nutrients and Klebsiella possibly outcompete other oral bacteria. The oral and nasal cavities may serve as reservoirs for multiple opportunistic pathogens this way.”
Additionally, Klebsiella can derive nutrients from dead bacteria, allowing it to survive for extended periods under starvation conditions. The researchers found that whenever Klebsiella was present in the oral or nasal samples, they persisted for over 120 days after being deprived of nutrition.
Other notable findings from the study include the observation that Klebsiella from the oral cavity, which harbours a diverse microbial community, was less prevalent and abundant than those from the nasal cavity, a less diverse environment. These findings suggest that microbial diversity and specific commensal (non-pathogenic) saliva bacteria may play a crucial role in limiting the overgrowth of Klebsiella species.
The groundbreaking research conducted by AFI scientists offers new insights into the transmission and spread of hospital-acquired infections, paving the way for more effective prevention and treatment strategies.
New research published in Arthritis & Rheumatologyindicates that chronic exposure to air pollutants may increase the risk of developing lupus, an autoimmune disease that affects multiple organs.
For the study, investigators analysed data on 459 815 participants from the UK Biobank. A total of 399 lupus cases were identified during a median follow-up of 11.77 years. Air pollutant exposure was linked with a greater likelihood of developing lupus. Individuals with a high genetic risk and high air pollution exposure had the highest risk of developing lupus compared with those with low genetic risk and low air pollution exposure.
“Our study provides crucial insights into the air pollution contributing to autoimmune diseases. The findings can inform the development of stricter air quality regulations to mitigate exposure to harmful pollutants, thereby reducing the risk of lupus,” said co–corresponding author Yaohua Tian, PhD, of the Huazhong University of Science and Technology, in China.
Infections and neurodegenerative diseases cause inflammation in the brain. But for unknown reasons, patients with brain inflammation often develop muscle problems that seem to be independent of the central nervous system. Now, researchers at Washington University School of Medicine in St. Louis have revealed how brain inflammation releases a specific protein that travels from the brain to the muscles and causes a loss of muscle function.
The study, published in Science Immunology, also identified ways to block this process, which could have implications for treating or preventing the muscle wasting sometimes associated with inflammatory diseases, including bacterial infections, Alzheimer’s disease and long COVID.
“We are interested in understanding the very deep muscle fatigue that is associated with some common illnesses,” said senior author Aaron Johnson, PhD, an associate professor of developmental biology. “Our study suggests that when we get sick, messenger proteins from the brain travel through the bloodstream and reduce energy levels in skeletal muscle. This is more than a lack of motivation to move because we don’t feel well. These processes reduce energy levels in skeletal muscle, decreasing the capacity to move and function normally.”
Fruit fly and mouse models
To investigate the effects of brain inflammation on muscle function, the researchers modelled three different types of diseases – an E. coli bacterial infection, a SARS-CoV-2 viral infection and Alzheimer’s. When the brain is exposed to inflammatory proteins characteristic of these diseases, damaging chemicals called reactive oxygen species build up. The reactive oxygen species cause brain cells to produce an immune-related molecule called interleukin-6 (IL-6), which travels throughout the body via the bloodstream. The researchers found that IL-6 in mice – and the corresponding protein in fruit flies – reduced energy production in muscles’ mitochondria, the energy factories of cells.
“Flies and mice that had COVID-associated proteins in the brain showed reduced motor function – the flies didn’t climb as well as they should have, and the mice didn’t run as well or as much as control mice,” Johnson said. “We saw similar effects on muscle function when the brain was exposed to bacterial-associated proteins and the Alzheimer’s protein amyloid beta. We also see evidence that this effect can become chronic. Even if an infection is cleared quickly, the reduced muscle performance remains many days longer in our experiments.”
Johnson, along with collaborators at the University of Florida and first author Shuo Yang, PhD (who did this work as a postdoctoral researcher in Johnson’s lab) make the case that the same processes are likely relevant in people. The bacterial brain infection meningitis is known to increase IL-6 levels and can be associated with muscle issues in some patients, for instance. Among COVID-19 patients, inflammatory SARS-CoV-2 proteins have been found in the brain during autopsy, and many long COVID patients report extreme fatigue and muscle weakness even long after the initial infection has cleared. Patients with Alzheimer’s disease also show increased levels of IL-6 in the blood as well as muscle weakness.
Potential treatment targets
The study pinpoints potential targets for preventing or treating muscle weakness related to brain inflammation. The researchers found that IL-6 activates what is called the JAK-STAT pathway in muscle, and this is what causes the reduced energy production of mitochondria. Several therapeutics already approved by the Food and Drug Administration for other diseases can block this pathway. JAK inhibitors as well as several monoclonal antibodies against IL-6 are approved to treat various types of arthritis and manage other inflammatory conditions.
“We’re not sure why the brain produces a protein signal that is so damaging to muscle function across so many different disease categories,” Johnson said. “If we want to speculate about possible reasons this process has stayed with us over the course of human evolution, despite the damage it does, it could be a way for the brain to reallocate resources to itself as it fights off disease. We need more research to better understand this process and its consequences throughout the body.
“In the meantime, we hope our study encourages more clinical research into this pathway and whether existing treatments that block various parts of it can help the many patients who experience this type of debilitating muscle fatigue,” he said.
