If smallpox is classified as an international threat to health, the WHO may issue temporary recommendations on how to prevent the disease and prevent it from spreading further.

Already last week, the WHO together with the EU's infection control authority ECDC warned that this summer's festivals and events could increase the spread.

The Public Health Agency's investigator, doctor Klara Sondén, then told TT that from previous experience it is known that summer is a period when sexually transmitted diseases become more widespread.

- This applies to sexually transmitted diseases in general - including monkey pox.

It may well be that the disease increases this summer, she told TT.

Today, there are more than 1,600 confirmed cases of smallpox in 39 countries, according to WHO figures.

In Sweden, there are 10 confirmed cases, according to the Swedish Public Health Agency's latest report.

The disease is spread mainly through close physical contact.

It is not entirely clear if the virus can also be spread in other ways.

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Do smallpox only spread at sex?

Watch virus researcher Ali Mirazimi review three common claims about the virus.

Photo: SVT / AP / CDC