This text was initially printed at The Conversation. The publication contributed the article to House.com’s Skilled Voices: Op-Ed & Insights.
For the primary time in 25 years of steady crewed operations, an astronaut has been medically evacuated from the Worldwide House Station (ISS). The Crew-11 mission ended when a SpaceX Dragon capsule introduced the four astronauts of Crew 11 house following a medical incident in early January 2026.
To protect the crewmember’s privacy, NASA hasn’t yet disclosed details about what happened – and this article won’t speculate. But the evacuation raises a question worth exploring: how do astronauts stay healthy in space, and why is this early evacuation so unusual?
Astronauts undergo rigorous medical screening earlier than choice. They’re assessed for circumstances which may worsen in microgravity, evaluated for psychological resilience, and monitored all through their careers.
Though modelling suggests a medical emergency may very well be anticipated roughly each three years on the ISS, severe points are remarkably rare in practice.
Each ISS mission contains medical assist each in house and on the bottom. Every crew has a chosen Crew Medical Officer – typically a professional physician, typically somebody with in depth coaching in house drugs procedures. They’ll carry out basic examinations, administer medications, and conduct telemedicine consultations with specialists on Earth.
What health issues do occur in space?
A 2015 study discovered that treatment use on the ISS was comparatively low, with roughly ten doses of over-the-counter treatment taken per astronaut per week, most of that are for widespread, manageable circumstances, corresponding to:
- Skin irritation is probably the most steadily reported medical concern in spaceflight. A latest systematic overview discovered that space-related dermatoses together with dry pores and skin, rashes, hypersensitivity reactions, and impaired wound therapeutic – happen at charges roughly 25 occasions greater than on Earth. The chilly, dry, low-humidity spacecraft setting exacerbates these issues, and hygiene is proscribed to moist wipes and rinse-less merchandise for months at a time.
- Congestion and headaches have an effect on most astronauts, significantly early in a mission. With out gravity pulling fluids downward, blood shifts towards the pinnacle, inflicting a puffy face and stuffy nostril – what astronauts name “house sniffles.” This may set off complications, reduced appetite, and poor sleep.
- Sleep disruption is widespread. The ISS orbits Earth each 90 minutes, creating 16 sunrises and sunsets over 24 hours, which disrupts circadian rhythms. Mixed with gear noise, decreased private house, and the stress of spaceflight, astronauts usually get one to 2 hours less sleep per night in comparison with on Earth.
- Musculoskeletal accidents are surprisingly widespread. A NASA study catalogued 219 in-flight accidents throughout the US house programme, with an incidence of roughly 0.02 per flight day.
- Hand accidents had been most frequent, largely small cuts from shifting between modules or dealing with gear. However train, mockingly the main countermeasure designed to guard astronauts’ bones and muscle mass, is now the leading source of injuries on the ISS.
Astronauts exercise for around two hours each day to fight bone and muscle loss and cardiovascular deconditioning in microgravity. With out gravity’s fixed load, bones can lose about 1% of their density per month, significantly within the legs, hips, and backbone.
But this important countermeasure carries its personal dangers. Spacewalks current further hazards – the research discovered 0.26 accidents per extravehicular exercise, typically brought on by spacesuit parts.
Analysis continues to make these countermeasures safer and simpler. At Northumbria College, the Aerospace Medicine and Rehabilitation Laboratory works with European House Company, NASA, Canadian House Company and personal spaceflight firms together with SpaceX to develop exercise-based interventions to guard astronaut well being. The analysis group are pioneering approaches to keep up bodily operate throughout longer missions and speed up restoration on return to Earth.
Space-specific conditions
Some health issues are unique to spaceflight. Spaceflight Associated Neuro-ocular Syndrome (SANS) affects up to 70% of astronauts on long-duration missions. The headward fluid shift changes pressure in the eye, leading to optic nerve flattening and vision changes that can persist for years after returning to Earth.
Perhaps most striking was an incident reported in 2020, when a blood clot was found in an astronaut’s jugular vein throughout a routine analysis ultrasound. The astronaut had no signs; the clot was discovered by probability. In what turned the last word telemedicine case, docs on Earth guided therapy over greater than 90 days.
Blood thinners had been administered, further treatment was despatched on a resupply vessel, and the astronaut carried out their very own ultrasound scans with radiologists directing from lots of of kilometers under. They accomplished their mission and returned safely on the finish of their mission with none well being penalties.
The Crew-11 evacuation demonstrates that house businesses prioritize crew security above all else. As missions transfer past low Earth orbit into deep house, new approaches to medical care will probably be wanted – known as Earth Independent Medical Operations, probably utilizing AI to help crew medical officers alongside classes from present missions.
That that is the primary expedited medical evacuation in 25 years highlights how successfully house drugs has developed. However it’s additionally a reminder that house stays inherently difficult for human biology, and typically there actually is not any place like house.
