Category: Diseases, Syndromes and Conditions

Categories : Diseases, Syndromes and Conditions NeurologyTags :

VZV Reactivation Is Driving CNS Infections

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Varicella zoster vires (VZV). Credit: NIH/NIAID

The varicella zoster virus (VZV), an infectious virus from the herpes virus family, is primarily known to cause varicella in children and shingles in adults. But lately, this virus has also been reported to trigger severe complications like central nervous system (CNS) infections. Researchers from Fujita Health University, Japan, conducted a comprehensive study spanning 10 years (2013–2022), to identify the VZV-related infections affecting the CNS. Their study reveals a marked increase in adult VZV-related CNS infections, particularly since 2019. The findings were published in the journal Emerging Infectious Diseases.

The study was led by Professor Tetsushi Yoshikawa, along with Hiroki Miura and Ayami Yoshikane from the Department of Pediatrics, Fujita Health University School of Medicine. The researchers analysed cerebrospinal fluid samples of 615 adult patients with suspected CNS infections. VZV DNA was most frequently detected in these patients, with its presence in 10.2% of the cases, and aseptic meningitis being the most common infection.

The data from 2019 to 2022 revealed that there was a noticeable rise in VZV DNA-positive cases, forming a distinct temporal cluster during this period. Professor Yoshikawa highlighted the results of the patient demographic analysis, reporting that “the proportion of aseptic meningitis increased from 50% between 2013 and 2018 to 86.8% between 2019 and 2022.” He further adds, “Similar to the rise in herpes zoster cases through VZV reactivation in the elderly, we believe this increase is also linked to VZV reactivation.”

The universal varicella vaccination, introduced in Japan in 2014, has reduced the natural booster effects from re-exposure to the virus. This potentially accelerates the immunity decline, leading to VZV reactivation, especially in cases like shingles. The researchers highlight the connection between the vaccination and the current scenario, saying, “The increase in VZV-induced CNS infections coincides with changes in varicella vaccination programs and emphasises the need for better preventive strategies.”

Furthermore, the researchers examined trends in VZV-induced CNS infection throughout the observation period using Kulldorff’s circular spatial scan statistics. As a result, it was confirmed that there was an accumulation of VZV-related CNS infections from 2019 to 2022. Although no direct causation was established, six patients did develop CNS infections after receiving COVID-19 vaccines.

“Further studies are needed to understand these interactions,” Yoshikawa notes. None of the eligible patients in this study had received the zoster vaccine, which was introduced in Japan in 2016. Increasing the number of VZV-related CNS infections underscores the importance of zoster vaccination in adults.

The research team stresses the broader implications of their findings, stating that the reactivation of VZV in the CNS is linked to an increased risk of dementia, including Alzheimer’s disease. They hypothesize, “If the prevention of VZV-related aseptic meningitis through herpes zoster vaccination is possible, these vaccinations could play a pivotal role in mitigating these risks of dementia.”

To address the growing concern, the research team advocates expanding public health initiatives to promote zoster vaccination among at-risk populations. “Our research underscores the necessity of proactive measures to prevent not just shingles, but also severe neurological complications associated with VZV,” explains Yoshikawa.

With the rise of the aging population and CNS infections, the study calls for urgent action to evaluate and implement comprehensive vaccination strategies to prevent CNS infections in the future.

Source: Fujita Health University

Categories : Diseases, Syndromes and ConditionsTags :

Interventions to Eliminate Vertical Transmission of Hepatitis B in Africa

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Photo by William Fortunato on Pexels

Researchers at the University of Liverpool have conducted a large-scale analysis that sheds light on the critical steps needed to combat the vertical transmission of chronic hepatitis B virus (HBV) in Africa.

Almost two thirds of all new hepatitis B infections globally occur in Africa. The newly published paper in The Lancet Global Health shows the importance of giving the hepatitis B birth dose vaccine (HepB-BD) within 24 hours of birth, and the potential impact of providing antiviral therapy (antiviral prophylaxis) to mothers during pregnancy. The study estimates for the first time that hepatitis B vertical transmission (passed from mother to baby) could be eliminated in Africa, with increased coverage of these two key interventions.

Chronic hepatitis B is the leading cause of liver cancer and liver cirrhosis in Africa and deaths are rising. Most cases of liver cancer are diagnosed late and are associated with a very poor prognosis in the region. Vertical transmission is one of the commonest routes of infection and is associated with an increased lifetime risk of severe liver disease.

Dr Alexander Stockdale, Senior Clinical Lecturer at the University’s Department of Clinical Infection, Microbiology and Immunology, based at the Malawi-Liverpool-Wellcome Trust Clinical Research Programme, together with Dr Nicholas Riches at Liverpool School of Tropical Medicine, led the comprehensive analysis of more than 113 individual studies which reported on the prevalence of hepatitis B in more than 190 000 women and investigated rates of vertical transmission.

The World Health Organization (WHO) African region faces a significant burden, accounting for 63% of the global total of new infections. This amounted to 771 000 new infections and 272 000 deaths in 2022. Among children under 5 years, the prevalence of HBV stands at 2.5% in the WHO African region – the highest globally.

Dr Alexander Stockdale said: “This study makes the case for investment in birth dose vaccination and maternal antiviral prophylaxis, in view of the exciting potential for elimination of vertical transmission in the WHO African region in our lifetime. Vertical transmission is a key route of new hepatitis B infections. Due to limited implementation of interventions, elimination targets are not currently being met. We project that expanding HepB-BD vaccination coverage to 90% could reduce transmission events by 44%, and adding maternal antiviral prophylaxis for 90% of eligible women could further reduce transmission by 86% and achieve the WHO targets for elimination.”

Dr Stockdale and colleagues have also recently been awarded £3million funding from the National Institute of Health and Care Research to conduct implementation research in Malawi and The Gambia. The NIHR Global Health Research Grant will allow researchers in Malawi, led by Dr Stockdale and in The Gambia, led by Professor Maud Lemoine and Dr Gibril Ndow, to evaluate the effectiveness, safety, feasibility and cost-effectiveness of giving antiviral treatment (tenofovir) to all pregnant women living with chronic hepatitis B to prevent transmission. This study will provide vital evidence on the potential impact of this strategy to guide public health policy in Africa, which has been recognised as a key knowledge gap by the WHO in the 2024 hepatitis B guidelines.

Source: University of Liverpool

Categories : Diseases, Syndromes and ConditionsTags :

Cold Sore Discovery Reveals an Unexpected Trigger for Flare-ups

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Scientists have a new target to prevent cold sores after University of Virginia researchers discovered an unexpected way the herpes virus re-activates in the body. The finding, published in PNAS, could also have important implications for genital herpes caused by the same virus.

The discovery from UVA’s Anna Cliffe, PhD, and colleagues seems to defy common sense. She and her team found that the slumbering herpes virus will make a protein to trigger the body’s immune response as part of its escape from dormancy. You’d think this would be bad for the virus – that activating the body’s antiviral defences would be like poking a bear. But, instead, it’s the opposite: The virus hijacks the antiviral process in infected neurons to make the type of comeback nobody wants.

“Our findings identify the first viral protein required for herpes simplex virus to wake up from dormancy, and, surprisingly, this protein does so by triggering responses that should act against the virus,” said Cliffe of UVA’s Department of Microbiology, Immunology and Cancer Biology. “This is important because it gives us new ways to potentially prevent the virus from waking up and activating immune responses in the nervous system that could have negative consequences in the long term.”

Herpes Simplex Virus-Associated Disease

Cold sores are caused primarily by herpes simplex virus 1 (HSV-1), one of two forms of the herpes virus. HSV-1 is very contagious, and worldwide more than 60% of people under 50 (more than 3.8 billion) have been infected, the World Health Organization estimates.

In addition to causing cold sores, herpes simplex virus 1 can also cause genital herpes, a condition most often associated with HSV-1’s cousin, herpes simplex virus 2. Now, however, there are more new cases of genital herpes in the United States caused by HSV-1 than HSV-2. Notably, the UVA researchers found that herpes simplex virus 2 also makes this same protein and may use a similar mechanism to reactivate. So UVA’s new discovery may also lead to new treatments for genital herpes. 

In addition to cold sores and genital herpes, HSV-1 can also cause viral encephalitis (brain inflammation) and has been linked to the development of Alzheimer’s disease.

Once HSV-1 makes its way into our bodies, it stays forever. Our immune systems can send it into hiding, allowing infected people to be symptom free. But stress, other infections and even sunburns are known to cause it to flare. UVA’s new discovery adds another, surprising way it can spring back into action.

The researchers found that while the virus can make a protein called UL12.5 to reactivate, the protein was not needed in the presence of another infection. The scientists believe this is because the infections trigger certain “sensing pathways” that act as the home security system for neurons. Detection of a pathogen alone may be sufficient to trigger the herpes virus to begin replicating, the scientists believe, even in instances of “abortive infections” – when the immune system contains the new pathogen before it can replicate.

“We were surprised to find that HSV-1 doesn’t just passively wait for the right conditions to reactivate – it actively senses danger and takes control of the process,” researcher Patryk Krakowiak said. “Our findings suggest that the virus may be using immune signals as a way to detect cellular stress – whether from neuron damage, infections or other threats – as a cue to escape its host and find a new one.” 

With the new understanding of how herpes flares can be triggered, scientists may be able to target the protein to prevent them, the researchers say. 

“We are now following up on this work to investigate how the virus is hijacking this response and testing inhibitors of UL12.5 function,” Cliffe said. “Currently, there are no therapies that can prevent the virus from waking up from dormancy, and this stage was thought to only use host proteins. Developing therapies that specifically act on a viral protein is an attractive approach that will likely have fewer side effects than targeting a host protein.” 

Source: University of Virginia Health System

Categories : Diseases, Syndromes and ConditionsTags :

Scans of Viking Skulls Reveal a Harsh Life of Disease

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Photo by Gioele Fazzeri on Unsplash

Sweden’s Viking Age population appears to have suffered from severe oral and maxillofacial disease, sinus and ear infections, osteoarthritis, and much more. This is shown in a study from the University of Gothenburg in which Viking skulls were examined using modern X-ray techniques.

About a year ago saw the publication of research based on the examination of a large number of teeth from the Viking Age population of Varnhem, known for its thousands of ancient graves and excavations of well-preserved skeletons.

Now, odontologists at the University of Gothenburg have taken this research further, looking at not only teeth but also entire skulls, by using modern computed tomography, also known as CT scans.

The results, presented in British Dental Journal Open, suggest that the 15 individuals whose skulls were examined suffered from a broad range of diseases. The CT scans show pathological bone growths in the cranium and jawbone, revealing infections and other conditions.

Detailed image analysis

Several individuals showed signs of having suffered from sinus or ear infections that left traces in the adjacent bone structures. Signs of osteoarthritis and various dental diseases were also found. All the skulls came from adults who died between 20 and 60 years of age.

The study lead, Carolina Bertilsson, is an assistant researcher at the University of Gothenburg and a dentist within Sweden’s Public Dental Service. The study was performed with specialists in dental radiology at the University of Gothenburg and an archaeologist from Västergötlands museum.

About a year ago saw the publication of research based on the examination of a large number of teeth from the Viking Age population of Varnhem in the Swedish province of Västergötland. Varnhem is known for its thousands of ancient graves and excavations of well-preserved skeletons.

Now, odontologists at the University of Gothenburg have taken this research further, looking at not only teeth but also entire skulls, by using modern computed tomography, also known as CT scans.

The results presented in British Dental Journal Open suggest that the 15 individuals whose skulls were examined suffered from a broad range of diseases. The CT scans show pathological bone growths in the cranium and jawbone, revealing infections and other conditions.

Detailed image analysis

Several individuals showed signs of having suffered from sinus or ear infections that left traces in the adjacent bone structures. Signs of osteoarthritis and various dental diseases were also found. All the skulls came from adults who died between 20 and 60 years of age.

The study lead, Carolina Bertilsson, is an assistant researcher at the University of Gothenburg and a dentist within Sweden’s Public Dental Service. The study was performed with specialists in dental radiology at the University of Gothenburg and an archaeologist from Västergötlands museum.

“There was much to look at. We found many signs of disease in these individuals. Exactly why we don’t know. While we can’t study the damage in the soft tissue because it’s no longer there, we can see the traces left in the skeletal structures,” says Carolina Bertilsson, and continues:

“The results of the study provide greater understanding of these people’s health and wellbeing. Everyone knows what it’s like to have pain somewhere, you can get quite desperate for help. But back then, they didn’t have the medical and dental care we do, or the kind of pain relief – and antibiotics – we now have. If you developed an infection, it could stick around for a long time.”

The study is described as a pilot study. One important aspect was to test CT as a method for future and more extensive studies.

“Very many of today’s archaeological methods are invasive, with the need to remove bone or other tissue for analysis. This way, we can keep the remains completely intact yet still extract a great deal of information,” says Carolina Bertilsson.

Source: University of Gothenburg

Categories : Diseases, Syndromes and Conditions EbolaTags :

Causes of Fevers of Unknown Origin in sub-Saharan Africa

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Ebola on a cell. Credit: NIH/NIAID

A new retrospective, laboratory-based observational study provides detailed insights into the causes of fevers of unknown origin in sub-Saharan Africa. Researchers examined 550 patients from Guinea who developed a persistent fever at the time of the major Ebola outbreak in 2014, but tested negative for the Ebola virus on site. The goal was to use modern diagnostic methods to better understand the underlying infectious diseases. The study is published in The Journal of Infectious Diseases.

Fever is a common symptom of many diseases, including infections, cancer, and autoimmune diseases. When the cause of a persistent fever remains unclear despite extensive investigation, it is referred to as fever of unknown origin (FUO). Approximately half of all FUO cases worldwide remain undiagnosed. In sub-Saharan Africa, malaria is often suspected and treated without laboratory confirmation or further investigation. However, 90 million pediatric hospitalisations per year in sub-Saharan Africa are due to fevers not caused by malaria but by other infections, often due to various bacteria and viruses.

A research team from the German Center for Infection Research (DZIF) and Charité – Universitätsmedizin Berlin, in collaboration with scientists from Guinea and Slovakia, conducted a retrospective observational study to thoroughly investigate the pathogen diversity of patients from Guinea with fever of unknown cause during a major Ebola outbreak in 2014. They combined epidemiological, phylogenetic, molecular, serological and clinical data.

Using serologic tests, PCR and high-throughput sequencing, at least one pathogen was detected in 275 of 550 patients. In addition to the expected malaria parasite Plasmodium, pathogenic bacteria such as Salmonella and Klebsiella strains were detected in almost one fifth of the patients. The frequent detection of resistance to so-called first-line antibiotics in the samples examined and the high rate of co-infections were also worrying: One in five infected patients had multiple infections at the same time. Pathogens causing malaria and bacterial sepsis were particularly common, occurring together in 12% of adults and 12.5% of children.

Infections with highly pathogenic viruses were also common: Yellow fever, Lassa and Ebola viruses were detected by RT-PCR in about six percent of patients. Of particular note was the detection of infection with Orungo virus, a little-known pathogen for which there are no robust assays. Using immunofluorescence assays, the researchers also identified IgM antibodies against several viruses, including Dengue, West Nile and Crimean-Congo hemorrhagic fever viruses, in patients who were PCR-negative.

“In Africa, febrile illnesses of unknown cause are often recognized and treated as malaria without further diagnosis. In our study, we were able to detect a pathogen in about half of all patients with FUO, including bacterial pathogens that cause sepsis, haemorrhagic fever viruses including Ebola, and, as expected, various strains of the malaria parasite Plasmodium,” explains the study’s last author Prof. Jan Felix Drexler.

The findings underscore the urgent need to further strengthen laboratory capacity in sub-Saharan Africa. Early detection of the infectious causes of FUO is critical for patient care, effective response to outbreaks, and development of regionally appropriate diagnostics.

“Our results show that regionally adapted treatment regimens should be discussed, that quality control in the context of outbreaks needs to be strengthened, and that knowledge of the pathogen spectrum can guide targeted strengthening of regional laboratories and translational research in the sense of point-of-care tests,” Drexler summarises the results of the study.

Source: German Center for Infection Research

Categories : Diseases, Syndromes and Conditions PaediatricsTags :

High Uric Acid Levels Linked to Mortality in Children with Severe Malaria

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Red Blood Cell Infected with Malaria Parasites Colourised scanning electron micrograph of red blood cell infected with malaria parasites (teal). The small bumps on the infected cell show how the parasite remodels its host cell by forming protrusions called ‘knobs’ on the surface, enabling it to avoid destruction and cause inflammation. Uninfected cells (red) have smoother surfaces. Credit: NIAID

Indiana University School of Medicine researchers and their collaborators in Uganda at the Makerere University School of Medicine have uncovered a significant connection between elevated uric acid levels and life-threatening outcomes in children with severe malaria.

Published in Nature Medicine, the study identified hyperuricaemia – high uric acid levels – as a potential contributor to increased mortality and long-term neurodevelopmental challenges in children with severe malaria. These findings open the door to future research that could improve treatment strategies for children affected by severe malaria, a disease caused by mosquito-transmitted parasites and a leading cause of death in African children.

“Our findings show that hyperuricemia is strongly associated with death in the hospital and after discharge and with long-term cognitive impairment in children with severe malaria,” said Chandy C. John, MD, paediatrics professor at IU School of Medicine, who co-led the study. “We also showed several mechanisms by which hyperuricaemia may lead to these outcomes, suggesting that hyperuricaemia is not just associated with bad outcomes but may contribute to them.”  

The researchers analysed data from two independent groups of children with severe malaria in Uganda and found that 25% had hyperuricaemia. This condition is caused by excess uric acid, which is a harmful body waste substance found in blood. The primary drivers of hyperuricaemia in study participants were broken-down infected red blood cells and kidney injury, which reduces the body’s ability to get rid of the extra uric acid. 

In the study, hyperuricemia was linked to four negative outcomes in children with severe malaria: serious health complications like coma and anaemia, a higher risk of death during hospitalisation, a higher risk of death after discharge from the hospital, and long-term cognitive impairment in survivors.  

The study also revealed that children with hyperuricemia had more harmful gut bacteria, which can cross the injured gut lining and cause sepsis. Together, these findings highlight a need for clinical trials to test the effectiveness of uric acid-lowering medications as an additional treatment for severe malaria. 

“Additional studies are needed to determine whether lowering uric acid in children with severe malaria might reduce hospital deaths, post-discharge deaths and long-term cognitive impairment,” said Andrea Conroy, PhD, associate professor of paediatrics at the IU School of Medicine and co-leader of the study. “Our hope is that these studies will provide new insights and potentially lead to improved treatments that save lives.” 

This research builds on the team’s recent discovery of partial resistance to the primary treatment for malaria in African children with severe malaria. Both studies underscore the importance of prioritizing new strategies to combat malaria, which affected 263 million people and caused nearly 600,000 deaths worldwide in 2023.

Source: Indiana University

Categories : Diseases, Syndromes and ConditionsTags :

Sound Also Disrupts Balance in People with Vestibular Hypofunction

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Visual information has long been proven to affect balance – for example, strobe lights and swirling images can cause instability – but a new study published in PLOS ONE shows that sounds can also be a disruptive factor for those who have vestibular hypofunction, a vestibular system disorder resulting in impaired balance.

“People with vestibular hypofunction have difficulty in places like busy streets or train stations where the overwhelming visual information may cause them to lose balance or be anxious or dizzy,” says lead author Anat Lubetzky, associate professor of physical therapy at NYU Steinhardt School of Culture, Education, and Human Development. “Sounds are not typically considered during physical therapy, making our findings particularly relevant for future interventions.”

The researchers conducted an experiment with 61 participants divided into two groups: healthy controls and individuals with unilateral vestibular hypofunction (affecting one ear).

Participants wore a virtual reality headset that simulated the experience of being in a New York City subway. As they experienced the sights and sounds of the “subway,” they stood on a platform that measured their body movement, while the headset recorded their head movement, two indicators of balance known as sway. Participants were provided with different subway scenarios: static or moving visuals paired with silence, white noise, or recorded subway sounds.

The results revealed that for the group with vestibular hypofunction, the moving visuals accompanied by audio (either white noise or subway sounds) resulted in the greatest amount of sway. This sway was evident on the body’s forward and backward movements, as well as head movements left to right, and head tilts upward and downward. Audio conditions did not affect the balance of the healthy individuals.

“What we’ve learned is that sound should be included as part of both the assessment of balance and intervention programs,” says Lubetzky.  “Because balance training is known to be task-specific, ideally, these should be real sounds related to patients’ typical environments and combined with salient and increasingly challenging visual cues. Portable virtual headsets are a promising tool for both assessing and treating balance problems.”

Source: New York University

Categories : Diseases, Syndromes and Conditions Obstetrics & GynaecologyTags :

Human Papillomavirus Infection Kinetics Revealed in New Longitudinal Study

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Improved understanding of why some infections persist could improve treatment, screening, and vaccination strategies for HPV infection

Non-persistent human papillomavirus (HPV) infections are characterized by a sharp increase in viral load followed by a long plateau, according to a study published January 21st in the open-access journal PLOS Biology by Samuel Alizon of the National Centre for Scientific Research (CNRS), France, and colleagues.

Chronic HPV infection is responsible for more than 600 000 new cancers each year, including nearly all cervical cancers. Infection among young women is common, impacting nearly 20% of women 25 years of age. Fortunately, the vast majority of these infections clear within two years without symptoms. Still, a better understanding of why some infections clear while others persist could improve treatment, screening, and vaccination strategies for HPV-associated diseases.

To monitor the dynamics of HPV infection, the PAPCLEAR cohort study in France followed 189 women aged 18 to 25 years for up to 24 months. Researchers followed participants every two months, collecting information on viral kinetics and immune markers.

By frequently monitoring participants, the researchers achieved unprecedented temporal resolution on viral and immune kinetics. They found that non-persistent infections are characterised by a plateau in HPV viral load that starts around 2 months after infection and lasts for 13 to 20 months before rapidly declining. Additionally, they found a strong correlation between a population of immune cells in between innate and adaptive immunity, namely TCRγδ cells, and the total amount of viruses produced.

The study is limited by the fact that many of the infection follow-ups were truncated, meaning that the participants were already infected when enrolled or were lost to follow-up before infection clearance. Furthermore, only 4 out of 76 infected participants were followed for 18 months or more. Therefore, differences between chronic and acute infections will have to wait for longer studies.

The authors add, “Asymptomatic genital infections by human papillomaviruses (HPVs) display striking dynamics at the frontier between acute and chronic infections. HPV infections appear to be associated with specific patterns of the innate and adaptative local immune response.”

Provided by PLOS

Categories : Diseases, Syndromes and ConditionsTags :

Sleep Apnoea Treatment Reduces Risk of Getting into Car Accidents

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Photo by Why Kei on Unsplash

Sleepiness at the wheel is a significant contributing factor to motor vehicle accidents. A new analysis published in Otolaryngology–Head and Neck Surgery reveals that for people with sleep apnoea, getting surgery for their condition may lessen their risk of such accidents compared with using a Continuous Positive Airway Pressure (CPAP) device at night or receiving no treatment.

In the analysis of data on 2 832 437 patients with obstructive sleep apnoea, 3.4% of patients who underwent surgery were in a car accident at any point following their diagnosis, compared with 6.1% of those using a CPAP and 4.7% of those not receiving any treatment.

Patients receiving no treatment had 21% higher odds of motor vehicle accidents compared with the surgery group. The surgery group had 45% lower odds compared with the CPAP group.

Patients with obstructive sleep apnoea who experienced accidents were more likely to have comorbidities such as hypertension, diabetes, and heart failure following the accident.

“Our findings underscore the profound impact that inadequately managed obstructive sleep apnoea can have on individual health and public safety,” said corresponding author Elliott M. Sina, BA, a medical student at the Sidney Kimmel Medical College at Thomas Jefferson University. “This work adds to the growing body of evidence supporting surgical interventions such as hypoglossal nerve stimulation as an effective alternative treatment for select patients with obstructive sleep apnoea.”

Source: Wiley

Categories : Antibiotics Diseases, Syndromes and ConditionsTags :

The Spread of a Highly Drug-resistant Cholera Strain

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Scanning electron micrograph image of cholera bacteria.

Scientists from the National Reference Center for Vibrios and Cholera at the Institut Pasteur, in collaboration with the Centre hospitalier de Mayotte, have revealed the spread of a highly drug-resistant cholera strain from Yemen down through Africa. The study was published in the New England Journal of Medicine.

Cholera is caused by the bacteria Vibrio cholerae and in its most severe forms, it is one of the most rapidly fatal infectious diseases: in the absence of treatment, patients can die within hours. Treatment primarily involves replacing lost water and electrolytes, but antibiotics are also used in addition to rehydration therapy. They are essential in reducing the duration of infection and breaking chains of transmission as quickly as possible.

A strain resistant to ten antibiotics – including azithromycin and ciprofloxacin, two of the three recommended for treating cholera – was identified for the first time in Yemen during the cholera outbreak in 2018-2019[1].

Scientists have now been able to trace the spread of this strain by studying the bacterial genomes. After Yemen, it was identified again in Lebanon in 2022[2], then in Kenya in 2023, and finally in Tanzania and the Comoros Islands – including Mayotte, a French département off the south-east coast of Africa – in 2024. Between March and July 2024, the island of Mayotte was affected by an outbreak of 221 cases caused by this highly drug-resistant strain.

“This study demonstrates the need to strengthen global surveillance of the cholera agent, and especially to determine how it reacts to antibiotics in real time. If the new strain that is currently circulating acquires additional resistance to tetracycline, this would compromise all possible oral antibiotic treatment,” concludes Professor François-Xavier Weill, Head of the Vibrios CNR at the Institut Pasteur and lead author of the study.

[1] Press release 19/08/2023 – Genes fuelling antibiotic resistance in Yemen cholera outbreak uncovered

[2] https://www.nature.com/articles/s41467-024-51428-0

Source: Institut Pasteur