Concern is growing over the extent of the spread of the mpox virus in Europe after Germany reported its first case of the new 1b variant.

And the head of the drug company Roche said he believes there are more people in Europe with it than has so far been acknowledged.

Mpox is mainly spread through close skin-to-skin or mouth-to-skin contact with someone who has it, according to the World Health Organization. It can cause fever, a painful rash and enlarged lymph nodes. Although most people make a full recovery, in some cases it can be fatal.

The United States Centers for Disease Control and Prevention said there is no specific treatment approved for mpox infection, but a two-dose vaccine has been developed.

After an initial outbreak of the virus spread from the Democratic Republic of Congo to neighboring countries in August, the WHO declared the new virus variant a global health emergency when the first infection was spotted outside Africa in Sweden.

Germany's disease control agency the Robert Koch Institute said the risk to the general public remains low, and the case in Germany, which was detected on Friday, was acquired abroad but it "is monitoring the situation very closely and adjusting its recommendations if necessary".

Norway cases

On Tuesday, two patients in Norway were diagnosed with the clade 2 variety of the mpox virus, which is less severe than the 1b strain. Authorities are looking to see if the two cases are connected.

"It seems like there are more mpox cases already in Europe, maybe not all of them are in the media yet," said Roche CEO Thomas Schinecker, adding there was not yet much demand for test kits, but that his company could up the production tenfold if required.

In an interview with Al Jazeera, Ahmed Ogwell, vice-president of global health strategy at the United Nations Foundation, said the interconnectedness of the modern world meant that "an outbreak anywhere is a risk of an outbreak everywhere", but lessons could be taken from previous global disease concerns.

"The risk is still high for spread because of the ease of communication that we have around the world today," said Ogwell, who is also former deputy director-general of the Africa Centers for Disease Control and Prevention.

On the specific topic of mpox, he added: "Someone can carry it to another part of the world easily and can transfer it, setting off a chain that results in something bigger than it is right now ... we need to put into good use the lessons of COVID, Ebola, cholera."