Bahrain remains on high alert to prevent a killer virus that has claimed more than 100 lives in Saudi Arabia - including eight that died yesterday (April 28), a top Health Ministry official said.

Despite treating 400 suspect cases of the Middle East Respiratory Syndrome (Mers-CoV) infection since 2012, no one has tested positive.

Yet the World Health Organisation (WHO) expects the virus to spread to other countries and says it is extremely difficult to contain.

Despite the increase in cases no further measures were needed, Health Ministry primary care and public healthcare assistant under-secretary Dr Mariam Al Jalahma was quoted as saying in the Gulf Daily News, our sister publication.

"Because the virus is limited to one country the WHO has not recommended any further action," she said.

"Even the WHO states in its recommendations that it doesn't advise special screening at points of entry yet.

"In regards to the case reported in Egypt - the victim was working and caught it in Saudi - if he got the symptoms on day earlier it would have been a Saudi case so, in terms of it spreading that doesn't really count."

According to the latest reports, the number of recorded Mers-CoV infections has reached 339, with 143 cases announced globally since the start of month - a 73 per cent increase on the figures for March.

Mers-CoV can be transmitted from person to person, Dr Al Jalahma said, but it is far less contagious than other diseases like swine flu.

With more than 200,000 people crossing the King Fahad Causeway every week, some commuters fear that they will catch it.

Symptoms include extreme difficulty in breathing and severe flu-like condition that requires treatment in hospital and - in more than a third of cases - death.

"The occurrence of new cases seems to follow a seasonal pattern, with increasing incidence from March-April onwards," said the WHO's latest risk assessment report.

"The number of cases sharply increased since mid-March 2014, essentially in Saudi Arabia and the UAE, where two important healthcare-associated outbreaks are occurring.

"It is very likely that cases will continue to be exported to other countries, through tourists, travellers, guest workers or pilgrims, who might acquire the infection following an exposure to the animal or environmental source, or to other cases, in a hospital for instance," the report read.

"Whether these cases will further transmit will depend of the capacity of the receiving country to rapidly detect, diagnose and implement appropriate infection prevention and control measures.

"As much as 75 per cent of the recently reported cases appear to be secondary cases, meaning that they are considered to have acquired the infection from another infected person.

"The majority of these secondary cases are mainly healthcare workers who have been infected within the healthcare setting, although several patients who were in the hospital for other reasons are also considered to have been infected with Mers-CoV in the hospital." – TradeArabia News Service