'Good' bacteria may help prevent meningitis

Researchers have found that nasal drops of a "good" bacterial strain can help prevent the deadly disease meningitis. The findings could lead to a new approach that could help suppress meningitis outbreaks.

"It is the first time that anyone has taken a bug -- a friendly bacterium -- and has shown that it changes the way that you can become colonised by the meningitis bacterium, Neisseria meningitidis," said study author Robert Read from University of Southampton.

Meningitis can be life threatening and the first symptoms of the disease are usually fever, vomiting, headache and feeling unwell.

In the study, published online in the journal Clinical Infectious Diseases, researchers placed drops containing low doses of Neisseria lactamica, a related but harmless bacterial strain, into the noses of 149 healthy university students in Britain.

A control group of 161 students received drops of saline instead. Nose swabs were taken at regular intervals over six months and tested for both types of bacteria.

Among students who received the N lactamica drops and became colonised, the harmless bacteria appeared to prevent N meningitidis from colonising the students' throats.

The "good" bacteria also displaced the worrisome pathogen in those who were already carrying it when the study began.

The effect was seen after just two weeks, when the number of students carrying N. meningitidis in their upper airway dropped by 9.5 percent among those who were also colonised by N lactamica using the drops. The effect lasted for at least four months, the researchers noted.

The findings suggest that N lactamica may one day be used as a bacterial medicine to help suppress meningococcal outbreaks.