Hundreds of masked-up students queued Wednesday to get vaccinated at the UK university campus at the heart of a deadly meningitis outbreak, as the number of cases rose to 20.

"It's quite a concerning thing. It all happened so fast," said Jack Jordan, a 19-year-old student at the University of Kent in southeast England, where the first case was reported on Friday.

By the weekend, one university student and one schoolgirl had died of the infection, with several others seriously ill in hospital in the outbreak, linked to a local nightclub.

At least 200 students formed a long queue at the grassy campus near the medieval city of Canterbury, as the university rolled-out a targeted vaccination programme for meningitis B -- a deadly bacterial strain.

Holly Francis, 18, returned to get the jab after leaving and moving back home earlier in the week. "Just to be extra safe," she told AFP.

"It kind of came out of nowhere," Francis said. "Everyone was very panicked and worried."

The rest of the campus remained largely empty after exams were cancelled or moved online.

Scattered conversations focused on the disease -- which affects the protective membranes surrounding the brain and spinal cord.

Prime Minister Keir Starmer led urgent calls for young people who visited the Canterbury nightclub to come forward, adding health experts were working to identify close contacts of those who were ill.

He asked "anyone who attended Club Chemistry on March, 5, 6th or 7th to come forward, please, to receive antibiotics".

'Deja vu'

All the cases linked back to that nightclub, Health Minister Wes Streeting said.

The number of cases being probed by UK authorities has risen since Tuesday from 15 to 20.

One involved a patient who had been living in Kent, but who was taken ill in London, amid fears the disease could spread as students head home for the Easter vacation.

French authorities also reported one case involving a person in France, who had attended the University of Kent.

Meningitis is a potentially deadly infection, most common in young children, teenagers and young adults.

Initial symptoms of meningitis include headache, fever, drowsiness and a stiff neck -- but those signs can be vague, hampering prompt diagnosis.

It can progress rapidly and is spread through prolonged close contact, including kissing or the sharing of vapes or drinks.

Glenn Reeve, 27, who went to Club Chemistry at the weekend, said he had been "feeling a bit rough" as he collected antibiotics.

"I felt a little panicky," Reeve told AFP, adding he would be cautious about "sharing drinks and being too close to people".

"It's almost like deja vu from Covid," said the train worker, adding being able to access antibiotics was "reassuring".

"As of 5:00 pm on 17 March, nine laboratory cases are confirmed and 11 notifications remain under investigation," bringing the total to 20, the UK Health Security Agency (UKHSA) said in a statement.

'Halt the spread'

Six of the confirmed cases are of group B meningococcal disease, according to the UKHSA.

The bacterial strain is rarer and deadlier than the viral type.

Doctors nationwide have been told to prescribe antibiotics to anyone attending their surgeries who visited Club Chemistry between March 5-7 and to University of Kent students "if they have been asked to seek preventative treatment".

The UKHSA said it was also investigating the case of a baby with confirmed meningococcal group B infection, but who was apparently not linked to the outbreak.

The baby girl is reportedly in hospital in nearby Folkestone.

Children in Britain are usually routinely vaccinated against meningitis B with three doses given at eight and 12 weeks and one year.

Another vaccination targeting meningococcal groups A, C, W and Y is offered to children aged 14.