To estimate the effectiveness of two or three doses of vaccines against covid-19 infection and hospitalisation, researchers in Denmark conducted a study of all previously uninfected Danish residents aged 12 years and older. The conclusion of the research, which is published in PLOS Medicine, is that a third dose provided greater protection against infection and hospitalisation with omicron than two vaccines.

This summer's monsoon rains in Pakistan are ten times heavier than usual and have already affected more than 33 million people. Some six and a half million are in need of humanitarian assistance, including more than 400,000 refugees. Pakistan's prime minister has called them "the worst in the country's history".

A study published in the BMJ has found a link between overall ultra-processed food consumption and an increased risk of colorectal cancer in men. The association has not been seen in women.

Using data from the UK Biobank, where black tea consumption is common, researchers have examined whether its intake is associated with a lower risk of mortality. Participants who reported drinking two or more cups a day had a 9-13% lower mortality risk compared to non-tea drinkers. The results are published in the Annals of Internal Medicine.

The extraordinary plenary session of the Congress of Deputies today approved the reform of the Law on Science, Technology and Innovation. After being passed in the Lower House without any votes against it on 23 June, the bill was approved in the Senate on 20 July with an amendment referring to indefinite-term contracts, which was rejected today in Congress. 

Research estimates that the rise in global average temperatures could approach 2 ˚C by 2050. The study, published in Communications Earth and Environment, estimates that by 2100 many people living in tropical regions will be exposed to dangerously high levels of heat on most days of the year. In addition, deadly heatwaves, which are currently rare in mid-latitudes, could occur every year in these areas.

Research published in Nature shows the creation of synthetic mouse embryos derived from stem cells. The embryo model copies the stages of natural rodent embryo development that take place up to day 8.5 after fertilisation and includes regions of the brain, a neural tube and a structure similar to a beating heart.

A study published in the New England Journal of Medicine has analysed the effectiveness of the antiviral drug Paxlovid after implantation of the omicron variant. The relative risk of severe disease decreased markedly in patients over 65 years of age, both vaccinated and unvaccinated. No differences were found in those under 65 years of age.

Using data from the 2017 National Health Interview Survey, researchers show that children and adolescents (aged 4-14 years) who skip breakfast or eat it away from home are more likely to have psychosocial behavioural problems. The research is published in the journal Frontiers in Nutrition.

Research published in PNAS shows how, in a sample of more than 1,600 racially diverse (black and white) parents in the United States, freedom of school choice, regardless of the presence of students of other ethnicities, also increases segregation. The authors attribute this to different preferences between black parents, who favour higher school ratings, and white parents, who prefer proximity to the school.