HEALTH news in brief

Microbe mix unique to each individual; second-hand smoke bad for asthma kids

Every individual emits their own microbial cloud by which they can easily be identified, researchers show

PUBLISHED : Thursday, 24 September, 2015, 12:02pm
UPDATED : Thursday, 24 September, 2015, 12:02pm

Everyone has a unique microbial signature, new research shows

Our fingerprints are our unique signatures, but University of Oregon researchers have found another: our personal microbial cloud. We each give off millions of bacteria from our human microbiome to the air around us every day. In the study published last week in the peer-reviewed journal PeerJ, the researchers sequenced microbes from the air surrounding 11 different people in a sanitised experimental chamber. They found that most of the occupants sitting alone in the chamber could be identified within four hours just by the unique combinations of bacteria in the surrounding air. The striking results were driven by several groups of bacteria that are ubiquitous on and in humans, such as Streptococcus, which is commonly found in the mouth, and Propionibacterium and Corynebacterium, both common skin residents. Different combinations of those bacteria were the key to distinguishing individual people.

Second-hand smoke at home raises risk of hospital admission for children with asthma

Children with asthma who are exposed to second-hand smoke at home have nearly double the risk of being admitted to hospital than their asthmatic peers from a smoke-free home. An article in the Annals of Allergy, Asthma and Immunology reviewed 25 studies investigating smoking exposure at home. More than 430,000 children were included, with a mean age of 7.6 years. "Previous studies have linked second-hand smoke exposure with increased asthma prevalence, poorer asthma control and increased symptoms," says Zhen Wang, lead author of the study. The article says children are perhaps more likely to be negatively affected by cigarette exposure than adults due to the immaturity of their lungs and immune systems. In addition, toxins such as second-hand smoke reduce lung growth rates.

Some forms of dizziness after getting up may signal bigger problems

Feeling faint after standing due to a sudden drop in blood pressure can be a minor problem due to medication use or dehydration. But when it happens often, it can be a sign of a more serious condition called orthostatic hypotension and an increased risk of death, according to new research that appeared last week in Neurology. Orthostatic hypotension is defined as a drop in blood pressure within three minutes of sitting or standing. For the study, researchers reviewed the medical records of 165 people with an average age of 59 who completed nervous system testing and were followed for 10 years. Of those, 48 were diagnosed with delayed orthostatic hypotension, 42 had orthostatic hypotension (a more severe form of the disease) and 75 did not have either condition. The study found that over 10 years, 54 per cent of participants with delayed orthostatic hypotension progressed to orthostatic hypotension and 31 per cent developed a degenerative brain disease such as Parkinson's or dementia with Lewy bodies. The rate of death over 10 years was 29 per cent for people with delayed orthostatic hypotension, 64 per cent for those with orthostatic hypotension and 9 per cent in people without either condition.