Nearly half of the world's population is at risk from dengue fever. Diagnosed cases have increased eightfold in the last decade, a rise fuelled by global warming. August 26 marks the International Day against this disease endemic in more than 100 tropical and subtropical countries, which is beginning to affect new areas, including Europe.

Counting deaths attributable to the effects of high temperatures is basic as a public health surveillance tool, but it should not become the only research objective. It is necessary to know why the population in some places adapts better than others to heat waves, what variables influence them, and to modify them when possible.

With the prolonged meteorological drought we find ourselves in, we are focusing too much on climate as its cause, while there is a lack of debate about the real problem: chronic water demand. It is necessary to rethink consumption models with all the actors of society and the competent administrations. A future adapted to climate change must address drought by prioritizing the restoration of our water systems and questioning the current development model.

Today it is difficult to see science policies that do not mention citizen science or citizen participation in science. On World Mosquito Day, which is celebrated on August 20, we analyze what has been achieved by the Mosquito Alert project, based on citizen science and which the Ministry of Health has supported this summer within the framework of the National Plan for Disease Prevention, Surveillance and Control Transmitted by Vectors.

The fires in Hawaii, which have left at least a hundred dead and hundreds missing, have devastated entire towns and villages and have put the issue of how to prevent such intense fires back on the table. World Wildfire Prevention Day is celebrated this Friday 18 August. The increase in the occurrence and recurrence of large wildfires jeopardizes the resilience of socio-ecological systems. Efforts in prevention must be a priority and constant throughout the year. We have a joint responsibility as a society to face this unprecedented problem, which will worsen in the coming years.

In 64 % of the cases, the temperature thresholds that define a heatwave according to the Ministry of Health are below the heatwave threshold established by AEMET. This implies that the population does not perceive situations of risk to their health when they do exist.

We compared semen analyses of 45 patients before and after mild covid-19 infection. We found a significant decrease in sperm volume, sperm concentration, total and progressive motility and vitality after infection, and that these effects may be long-term.

The latest episode of competition between research groups working on the same topic, a very common situation in science, should not distract us from the actual achievement: synthetic human embryos, in the laboratory, made from stem cells, up to a post-implantation stage. Now, we must decide what status or condition we will grant to these synthetic embryos. Once again, science is leaping forward and testing the limits of the laws, posing new ethical challenges for us to solve. 

The current situation is only the beginning of what may come in the coming decades, which should lead us to increase efforts in mitigation and adaptation strategies: more green and shaded areas, energy efficiency in buildings and avoiding working outdoors in extreme temperatures.

This year's theme for 8M is "For an inclusive digital world: innovation and technology for gender equality". If we want to innovate for everyone, there must be women doing research in mathematics, an essential discipline in the fields of technology, finance and health. However, the future of mathematical research in Spain has a male profile and this is worrying: advances and major decisions will be made excluding half of the population.