LONDON (Reuters) - STEC (serotype Enterotoxigenic Respiratory Syncytial Virus) is the top germ for which there are no cure or vaccine treatments, with 223 confirmed cases in the European Union in 2018, the health regulator for the 27 countries said on Wednesday.

The number of cases of STEC, which can cause severe respiratory infections and pneumonia, has shot up in recent years - and even though it continues to be prevalent, it is no longer the top baddie.

Instead, it has been overtaken by the notorious K-rival MRSA (methicillin-resistant Staphylococcus aureus), which has now been found in 185 confirmed outbreaks across the EU.

The European Centre for Disease Prevention and Control said a handful of antibiotics may slow the progress of K infections in certain populations, but no new drugs have reached the market to date.

“The number of health care-associated infections caused by new pathogens has increased drastically over the past ten years,” it said in a statement.

Hepatitis B - the top cause of infections in healthcare facilities - slipped to third place in the ECDC’s rankings from first in 2017, though it remains one of the top-spreading viruses.

It was followed by the human papillomavirus or HPV - the most common sexually transmitted infection worldwide - and now only accounts for 190 confirmed outbreaks across the bloc.

The ECDC does not classify a virus as a “known” cause of an outbreak, but it usually rates whether a bacterium like K or a virus like Hepatitis B has been detected.