The disease is spread by contact with respiratory secretions and usually lasts for 5 days.

He said that the disease could strike at any time during the year, and could be spread through respiratory secretions like sneezing or coughing.

Mumps, for example, is spread through direct contact with respiratory secretions or saliva.

"It theoretically will be secreted in nasal and respiratory secretions in very small amounts."

After exposure to the cold viruses, the researchers examined the volunteers' upper respiratory secretions for evidence of viral infection.

The boy's doctor had forwarded a routine sample of his respiratory secretions to researchers at the Department of Health.

They also know that the virus is spread through contaminated blood, and possibly urine and respiratory secretions.

Also, samples of respiratory secretions or samples from affected tissues may be sent to the laboratory for fungal culture.

But the presence of anthrax can be determined by laboratory tests of the blood, skin and respiratory secretions.

Urine, faeces and respiratory secretions may also shed the virus.