The Prince of Sweden and his wife Princess Sophia both tested positive for COVID-19, as their country struggles under a brutal second wave of infections

• Prince Carl Philip and his wife, Princess Sophia, have both tested positive for COVID-19 after showing symptoms of the coronavirus.
• The pair attended a funeral with the reigning King of Sweden and other members of the royal family on Friday, and they showed negative test results then.
• The king, queen, crown princess and her husband have all been tested for the virus since the two infections were discovered. So far, their tests results remain negative. 
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The coronavirus has hit Swedish royalty amid a rapid surge in cases across Sweden. 

The Swedish royal Family announced Thursday that both Prince Carl Philip, and his wife Princess Sophia had tested positive for COVID-19, the disease caused by the virus, after showing symptoms. 

"The prince and princess show milder flu symptoms, but feel well under the circumstances," the royal family said in a statement. 

Carl Philip is the only son of 74-year-old King Carl XVI Gustav, and he is fourth in the line of succession to the Swedish crown, after his older sister Crown Princess Victoria and her two children. 

Prince Carl Philip and Princess Sophia have been isolating themselves at home in Stockholm with their two young sons since Wednesday, according to the royal family. 

The king, queen, and crown princess of Sweden 'remain healthy'

There was some concern about whether other members of the royal family may have been exposed to the virus too, as both Princess Sofia and Prince Carl Philip attended a private funeral with the reigning king, queen, crown princess, and her husband on Friday.

But in a follow-up statement Thursday, Sweden's royal family said all of those individuals have now been tested, and their results are negative, and they "remain healthy" — at least so far. 

Test results can change. It's possible that more royal infections could surface in the coming days. Indeed, all of the members of the royal family who attended the funeral together on Friday — including Prince Carl Philip and Princess Sophia — were tested for COVID-19 prior to attending that event, and their results at the time were negative.

It usually takes at least a few days for a coronavirus infection to incubate in your body, after you are exposed to a sick person or their germs, which is why public health experts recommend waiting about five to seven days after an exposure to get a test.

The rate of coronavirus infections across Sweden has been on a dramatic uptick since late October.

Sweden is fighting the virus with tougher restrictions this time

Sweden had received harsh criticism for its comparatively lax, lockdown-free pandemic strategy in the spring, which lead to many deaths in the country's nursing homes then. 

Swedish health authorities have now backtracked on the herd immunity approach, and are implementing a few more restrictions.

In Stockholm, for example, "residents are told not to attend or throw parties, to avoid indoor locations like shops and museums, and to avoid unnecessary trips on public transport," as Business Insider's Sinéad Baker recently reported.

During the spring surge, Princess Sophia had volunteered at a private hospital in Stockholm, helping out with cleaning, and some basic patient care. 

"To be able to help in this difficult time is extremely rewarding," she wrote in Swedish on Instagram then.