Congo’s Ebola outbreak has passed 9,500 confirmed cases while the United States has warned travellers about Kenya, where eight people have been infected. New studies link ultra-processed food to silent brain injury and ADHD to higher death rates, show how the cold sore virus alters brain immune cells and tie lithium in water to a rare heart condition.
Congo’s Ebola count passes 9,500 confirmed cases as the US warns travellers about Kenya
The Democratic Republic of the Congo had recorded 9,552 confirmed Ebola cases and 4,602 related deaths by 19 October, according to the European Centre for Disease Prevention and Control. Its latest update listed 97 new cases, 41 of them fatal, in North Kivu, Ituri and Haut-Uélé. The outbreak now reaches 66 of the country’s 178 health zones across eight provinces, with 937 patients in isolation wards and 2,550 people recovered.
Kenya has confirmed eight cases, including one death, since a Kenyan citizen who had been living in Congo travelled home through Uganda early in October and later died. Relatives and three health workers who had cared for him were among those infected, and the most recent patient, reported on 18 October, was a hospital attendant rather than a health worker. The United States has now raised its travel advisory for Kenya, citing the outbreak and security concerns.
The outbreak is caused by Bundibugyo virus, one of several viruses behind Ebola disease, named after the district in western Uganda where it was first identified and responsible for earlier outbreaks in 2007 and 2012. Health workers in eastern Congo say fear and stigma are fuelling a hidden mental health crisis among patients, survivors and bereaved families, worsened by conflict and displacement. The European agency judges the risk of the virus reaching Europe to be very low.
Adults who eat the most ultra-processed food show more silent brain injury on scans
Middle-aged Canadians who ate the most ultra-processed food were 40% more likely to show silent damage to the brain on MRI scans than those who ate the least, researchers at McMaster University have reported. The study of 8,783 adults aged 35 to 69, none with cardiovascular disease, was published on 15 October. It found such injury, meaning tiny silent strokes or heavy damage to small blood vessels, in 11.3% of the highest consumers against 8.1% of the lowest.
Lead author Russell de Souza said the changes matter because injury of this kind can be present years before symptoms emerge and is tied to later stroke and memory problems. The heaviest consumers also carried more body fat, including fat around the organs, but scored no worse on memory and thinking tests. The researchers said diet and scans were measured only once, so the study shows an association rather than a cause, and that repeat scans are under way.
Ultra-processed foods are industrially made products, usually shelf-stable and heavily flavoured, such as packaged snacks, sugary cereals, soft drinks, instant noodles and ready meals. The term comes from the Nova classification, set out by Brazilian researchers in 2009, which groups foods by how much they are processed. Population studies have linked high consumption to obesity and chronic disease, but few clinical trials have tested the effect, and a Harvard neurologist said eating less of them remains reasonable advice.
People with ADHD die at a higher rate, but medication may lower the risk
People diagnosed with attention deficit hyperactivity disorder die at a 70% higher rate from all causes than people without the diagnosis, according to a review by researchers at University College London and the University of Liverpool. The team pooled 19 long-term studies covering close to 16 million people on three continents, some of whom were followed for more than 20 years. Death rates were 90% higher for suicide, 55% higher for injuries and 27% higher for natural causes.
Among people with the condition, those taking ADHD medication had a mortality risk about 25% lower, although the researchers said that estimate rested on only three of the 19 studies. First author Lucy Corrigan said the result was early evidence that needs further research. Senior author Joshua Stott said the condition does not in itself shorten life, and that the findings show why everyone who may have it needs access to an accurate diagnosis and to treatment.
ADHD is a neurodevelopmental disorder marked by inattention, hyperactivity, impulsivity and difficulty regulating emotions, and it often occurs alongside other mental and physical conditions. The researchers said people with the diagnosis face more depression, risk-taking, exclusion and stigma, as well as higher rates of heart disease, diabetes and cancer, and often struggle to obtain and keep up with medical care. Treatment usually combines stimulant or non-stimulant medicines with psychological therapy, and diagnosis rates have risen in recent years.
Cold sore virus switches brain immune cells into a lasting defence mode, researchers say
The herpes simplex virus that causes cold sores reprogrammes the brain’s resident immune cells, according to researchers at the University of Colorado Anschutz Medical Campus. Their study, published at the start of October, found that infection pushes these cells, known as microglia, into an intense antiviral state driven by interferon signalling, while switching off genes they need for routine upkeep such as pruning connections between neurons and clearing waste. The changes were concentrated in the areas where the virus was present.
The team also found that the virus reorganised chromatin, the packaging of DNA inside the cell nucleus, changing which genes the cells can use. Senior author Christy Niemeyer said microglia act as both guards and caretakers of the brain, and that the shift may impair their everyday work even after the infection clears. Co-senior author Kimberley Bruce said the pattern resembles responses linked to Alzheimer’s disease, but stressed that the study does not show the virus causes it.
Herpes simplex virus type 1 is carried for life by more than 60% of adults worldwide and usually lies dormant in nerve cells outside the brain, reappearing from time to time as cold sores. Microglia make up around 5 to 10% of brain cells and are the main immune defence of the central nervous system, constantly removing plaques, damaged cells and infectious agents. Earlier research had suggested a link between the virus, long-term brain inflammation and late-onset Alzheimer’s disease.
Lithium in drinking water is linked to a rare heart rhythm condition in children
Children in Californian counties with the most lithium in their water were more likely to be diagnosed with Wolff-Parkinson-White syndrome, a rare heart rhythm condition present from birth, researchers at the University of California, San Francisco have found. The study, published on 13 October, examined the records of more than 2.3 million children and matched them with county measurements of lithium in groundwater and surface water taken between 1998 and 2020.
In counties with at least 32.6 parts per billion, the odds of a diagnosis were 60% higher after adjusting for income, insurance and other factors, yet only 686 children, about 0.03% of the total, had the condition. Records of 1.9 million patients in New York showed a weaker link at lower levels. Senior author Gregory Marcus said the findings should not alarm anyone about water safety, including pregnant people, and the researchers said a causal role remains unproven.
The syndrome involves an extra electrical pathway between the upper and lower chambers of the heart that can trigger a rapid heartbeat, palpitations or fainting and, rarely, cardiac arrest. It affects between 0.1% and 0.3% of people and can be treated by catheter ablation, which destroys the extra tissue, but its cause is usually unknown. Lithium, a common psychiatric medicine, also occurs naturally in groundwater, and its use in pregnancy has been associated with heart defects.