The main symptom is a blotchy red rash on the face, resembling slapped cheeks, that could later spread to other parts of the body.

Pregnant teachers who work in schools where there have been cases of slapped cheek virus are being advised by their doctors to remain at home to avoid complications, Times of Malta has learnt.

Over the past months several cases of slapped cheek syndrome have been detected among schoolchildren. The main symptom, caused by parvovirus B19, is a blotchy red rash on the face – resembling slapped cheeks.

Depending on the stage of pregnancy, there is “a small risk” of miscarriage or complications for the baby including heart failure and anaemia, according to the UK’s National Health Service.

Most pregnant women who get slapped cheek syndrome have healthy babies.

Expectant mothers who come into contact with the condition – that is, at its most contagious stage before symptoms are visible – are being told to play it safe and stay at home, Malta Union of Teachers president Kevin Bonello confirmed.

Most children will not need treatment as slapped cheek syndrome is usually a very mild condition

Several pregnant teachers and learning support assistants contacted the union because they were worried, he added.

“They are not only worried about the health aspect. They are also worried about catching up with the syllabus as students are approaching exam time…

“But, as a union, we are telling them to follow doctors’ orders,” Mr Bonello said when contacted.

He gave the example of one pregnant teacher who had been away from school for a week.

Mr Bonello said the union wrote to Education Minister Evarist Bartolo requesting that absences like this be considered as quarantine leave and not deducted from these teachers’ sick leave entitlement.

Quarantine leave, he explained, was resorted to in case of contagious diseases.

Mr Bonello said he knew of at least five schools where cases of slapped cheek syndrome had been reported.

When a case is detected in a school the health authorities instruct the principal to send a letter to parents of children in the same class as the infected student, with information on the disease.

Children in the same class are directed to follow general preventative procedures in class such as frequent hand-washing.

Parents are told not to send children with fever, rashes or any signs of illness to school.

The letter also reads: “If the mother of a child diagnosed with this virus or the teacher of a child diagnosed with this virus is pregnant then it is advised that you inform your gynaecologist that you were exposed to this virus.”

A Health Ministry spokesman said slapped cheek syndrome usually affected children between the ages of three and 15.

It was very rare that adults contracted the virus since they usually built immunity. No vaccination is available.

It is very difficult to prevent the spread of the airborne virus as people are most contagious before their symptoms start to show, so they are unaware that they are infected.

The symptoms usually show up in the first couple of weeks after the child is exposed tothe virus and starts off with flu-like symptoms.

“Most children will not need treatment as slapped cheek syndrome is usually a very mild condition that passes in a few days. Occasionally it can last up to four or five weeks,” the spokesman said.

The headaches, high temperature or itchy skin can be treated with over-the-counter medication.

The spokesman said children who have the virus should stay home until the infectious period is over; that is about four days after the facial rash appears.