The study, which explored the transmission of tuberculosis (TB) from infected patients to guinea pigs, suggests that installing simple ultraviolet C (UVC) lights in hospitals could help reduce the transmission of TB, including drug-resistant strains.
Every year, over nine million people are infected with tuberculosis and nearly two million people die from the disease, according to the World Health Organisation. Infection rates are particularly high in places where vulnerable people are crowded together, such as hospitals, homeless shelters and prisons.
When a tuberculosis patient coughs, bacteria are sprayed into the air in tiny droplets, floating around the room and infecting other patients, visitors and healthcare staff. These bacteria can be killed by hanging a shielded UVC light from the ceiling with a fan to mix the air, say the researchers, from Imperial College London, the University of Leeds, Hospital Nacional Dos de Mayo, Lima, Perú and other international institutions.
UVC light kills tuberculosis bacteria, including drug-resistant strains, by damaging their DNA so they cannot infect people, grow or divide. It is already used at high intensity to disinfect empty ambulances and operating theatres.
Dr Rod Escombe, the study's principal investigator from the Wellcome Trust Centre for Clinical Tropical Medicine at Imperial College London, said: "When people are crowded together in a hospital waiting room, it may take just one cough to infect several vulnerable patients. Our previous research showed that opening windows in a room is a simple way to reduce the risk of tuberculosis transmission, but this is climate-dependent – you can't open the windows in the intensive care ward of a Siberian hospital for example."
"Thankfully, the rate of tuberculosis infection in countries like the UK is relatively low and people who are infected can be treated using antibiotics, which are readily available here. People are more likely to die from the disease in developing countries like Perú, because there are limited resources for isolating patients, diagnosing them quickly and starting effective treatment. Also, the prevalence of drug-resistant TB is much higher in the developing world. Preventing infection is much easier and cheaper than treating a patient with tuberculosis," added Dr Escombe.
Plans are already underway to install upper room UV lights in the chest clinic at St Mary's Hospital, part of the Imperial College Healthcare NHS Trust, which will be the first hospital to have them in the UK.
Introducing UVC lights could be a relatively low-cost measure, say the researchers. Currently, a typical UVC ceiling light costs around US$350 and replacement bulbs cost from US$25. The researchers are now working to develop more affordable US$100 units.
The impact of UV lights is greatest when combined with careful management of the air flow on the wards, as Dr Cath Noakes from the University of Leeds' Faculty of Engineering explains: "The lights must be set high enough to ensure patients and health workers are not overexposed, but if the lights only treat air at that level, there will be little benefit. To be most effective, ventilation systems need to create a constant flow of treated air down to patient level, and potentially infected air up towards the lights."
To reach their conclusions, scientists hung UVC lights in a hospital ward in Lima, Perú where 69 patients with HIV and TB were being treated. The researchers pumped air from the ward up to a guinea pig enclosure on the roof of the hospital for 535 consecutive days. The guinea pigs were split into three groups of approximately 150: the first group received air exposed to the UV lights in the ward, the second group received ward air treated with negative ionisers, and the third control group was given untreated air straight from the ward. The guinea pigs were given skin tests for tuberculosis once a month.
By the end of the experiment, 35% of the control group were infected with TB, compared to 14% of the ionised air group and 9.5% of the UVC group. 8.6% of the control group developed the active form of the disease after being infected with TB, compared to 4.3% of the ionised air group and 3.6% of the UVC group.
Lucy Goodchild | EurekAlert!
How to design city streets more fairly
18.05.2020 | Mercator Research Institute on Global Commons and Climate Change (MCC) gGmbH
Insects: Largest study to date confirms declines on land, but finds recoveries in freshwater – Highly variable trends
24.04.2020 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig
In living cells, enzymes drive biochemical metabolic processes enabling reactions to take place efficiently. It is this very ability which allows them to be used as catalysts in biotechnology, for example to create chemical products such as pharmaceutics. Researchers now identified an enzyme that, when illuminated with blue light, becomes catalytically active and initiates a reaction that was previously unknown in enzymatics. The study was published in "Nature Communications".
Enzymes: they are the central drivers for biochemical metabolic processes in every living cell, enabling reactions to take place efficiently. It is this very...
Early detection of tumors is extremely important in treating cancer. A new technique developed by researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from normal tissue. The work is published May 25 in the journal Nature Nanotechnology.
researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from...
Microelectronics as a key technology enables numerous innovations in the field of intelligent medical technology. The Fraunhofer Institute for Biomedical Engineering IBMT coordinates the BMBF cooperative project "I-call" realizing the first electronic system for ultrasound-based, safe and interference-resistant data transmission between implants in the human body.
When microelectronic systems are used for medical applications, they have to meet high requirements in terms of biocompatibility, reliability, energy...
Thomas Heine, Professor of Theoretical Chemistry at TU Dresden, together with his team, first predicted a topological 2D polymer in 2019. Only one year later, an international team led by Italian researchers was able to synthesize these materials and experimentally prove their topological properties. For the renowned journal Nature Materials, this was the occasion to invite Thomas Heine to a News and Views article, which was published this week. Under the title "Making 2D Topological Polymers a reality" Prof. Heine describes how his theory became a reality.
Ultrathin materials are extremely interesting as building blocks for next generation nano electronic devices, as it is much easier to make circuits and other...
Scientists took a leukocyte as the blueprint and developed a microrobot that has the size, shape and moving capabilities of a white blood cell. Simulating a blood vessel in a laboratory setting, they succeeded in magnetically navigating the ball-shaped microroller through this dynamic and dense environment. The drug-delivery vehicle withstood the simulated blood flow, pushing the developments in targeted drug delivery a step further: inside the body, there is no better access route to all tissues and organs than the circulatory system. A robot that could actually travel through this finely woven web would revolutionize the minimally-invasive treatment of illnesses.
A team of scientists from the Max Planck Institute for Intelligent Systems (MPI-IS) in Stuttgart invented a tiny microrobot that resembles a white blood cell...
19.05.2020 | Event News
07.04.2020 | Event News
06.04.2020 | Event News
28.05.2020 | Transportation and Logistics
28.05.2020 | Physics and Astronomy
28.05.2020 | Power and Electrical Engineering