The Swiss Army has been trying to fight back but so far the blood-sucking bugs appear to be standing their ground, according to a report from the ATS news agency.

Officials discovered on Thursday that the bugs, parasitic insects that feed on human and other blood, infested six beds in a room in the barracks.

Despite the introduction of “emergency measures”, the infestation spread to a further two beds with a total of 20 beds affected, the federal Department of Defence announced on Monday.

The rooms are to be disinfected in the next two to three weeks by a private company specializing in eradication of pests, the department said.

Corridors and toilets will also be treated in the battle against the bugs.

Recruits who were quartered in the affected rooms have already been housed elsewhere, the defence department said.

Individuals who may have been in contact with the bugs are to receive medical attention “when needed”, the department said.

In addition their equipment will be replaced.

Bed bugs, so named because they favour bedding and warm sleep areas as habitat, feed on their hosts without being noticed.

But experts say a number of adverse health effects can result from bed bug bites.

Skin rashes, psychological effects and allergic symptoms may result.