Pre-exposure prophylaxis (PrEP), which usually consists of taking a daily oral anti-HIV drug, is a highly effective measure to prevent HIV infection. However, it only works well if people strictly follow the protocol, and some people end up not adhering to it. To improve this situation, researchers have tested an implant under the skin of non-human primates that releases the antiretroviral drug islatravir and maintains adequate concentrations for at least 20 months. The results, published in the journal Science Translational Medicine, show complete protection against infection with repeated exposure.

Living near green spaces over a long period of time is associated with better health, an association more marked in women and white people than in men and black people, according to a study conducted in four US cities. The analysis concludes that exposure to urban green space between 1985 and 2006 is associated with slower epigenetic ageing, and that this association is stronger in disadvantaged neighbourhoods. The international team publishing this paper in Science Advances includes a researcher from ISGlobal in Barcelona. 

A study concludes that climate change will lead to less precipitation in the form of snow and more extreme rainfall events, especially at high altitudes in the northern hemisphere, increasing the risk of floods, landslides and infrastructure damage. According to the authors, this is the first time this risk of extreme precipitation in liquid and solid form has been studied separately. Their calculations indicate that for each degree of temperature increase, the risk of extreme rainfall in high-altitude regions will increase by 15 %. The authors publish their results in the journal Nature.

An international team, involving researchers from Hospital Clínic-IDIBAPS and the Multiple Sclerosis Centre of Catalonia (Cemcat), has identified for the first time a genetic variant related to the progression of multiple sclerosis. It is located near two genes that had not previously been linked to multiple sclerosis. According to Stephen Sawcer, co-lead author of the study, "understanding how the variant exerts its effects on the severity of multiple sclerosis will pave the way for a new generation of treatments that can prevent disease progression". The results are published in the journal Nature.

Although outbreaks of H5N1 avian influenza have reached record numbers in recent years, human infections remain anecdotal. A study published today in Nature identifies a protein responsible for inhibiting the replication of this virus in humans, while 'human' flus are able to evade it. The authors propose that this protein with antiviral activity evolved in primates and consider that resistance or sensitivity to it should be taken into account when assessing the zoonotic potential of avian influenza viruses.

Berna Sozen's lab at Yale University has announced a new milestone in the competition to create synthetic embryos: their human pluripotent stem cells self-organise into structures that mimic embryonic development on days 9-14 after fertilisation and include extra-embryonic tissues. Their achievement is published in Nature at the same time as another similar study, that of Magdalena Zernicka-Goetz, who a fortnight ago previewed her stem cell-derived human embryo model to The Guardian, sparking a controversy with Jacob Hanna, author of a preprint showing that she had achieved true synthetic embryos. 

From May to August 2022, 157,580 deaths were recorded, 20.5% more than in the same months of 2019, before covid. This increase in mortality was mainly among people aged 75 years and older. Of the causes of death directly related to the heat, heat stroke and dehydration stood out. These are some of the provisional data published by the National Statistics Institute (INE) in relation to deaths in 2022. Covid-19 was the most frequent cause of death, with 31,559 people dying, 20% less than in 2021.

An analysis of data published in the journal General Psychiatry with more than 66,000 diagnoses of gender dysphoria, mostly made in the United States, concludes that prevalence increased between 2017 and 2021, and that the median age decreased over the same period from 31 to 26 years.

A research team describes in Nature the presence outside the solar system of CH3+, a cation that could react with other molecules to form complex organic molecules. Its role in interstellar organic chemistry was described decades ago, but until now it had not been observed outside the solar system. The team, which includes co-authors from the CSIC's Institute of Fundamental Physics and the National Astronomical Observatory in Madrid, based their work on observations from James Webb Telescope.

If effective strategies are not developed, more than 1.3 billion people will be living with diabetes by 2050, some 800 million more than today. This is according to the lead study in a set of papers published in The Lancet and The Lancet Diabetes & Endocrinology. In addition, 75% of these people will live in low- and middle-income countries, which is largely due to "structural racism and inequality", according to the editorial accompanying the studies.