By Sandra Rose  | 

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Belgium became the first country to order a mandatory 21-day quarantine for men infected with the deadly monkeypox virus.

"Those infected with the monkey pox virus must be in isolation for 21 days," the Dutch publication Standaard reported.

Belgium ordered the lockdown after the country hosted a massive gay pride festival attended by an estimated 80,000 men in Antwerp.

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More than 100,000 people celebrated the annual Pride Parade in the streets of Brussels on May 21, 2022.

On Monday, Britain became the second country to introduce mandatory 21-day lockdowns.

Additionally, the World Health Organization (WHO) is issuing quarantine guidance to 11 more countries where monkeypox cases have popped up.

As previously reported, 89 confirmed cases of monkeypox in Europe are all men who have sex with men (MSM).

The Gran Canaria pride festival, held between May 5 and May 15, has been labeled a "superspreader" event after attendees traveled, spreading the virus worldwide.

"The Gran Canarian pride festival attended by 80,000 from Britain and across Europe is being investigated after being linked to numerous monkeypox cases in Madrid, Italy and Tenerife," the Daily Mail reported.

Symptoms of monkeypox include fever, headache, muscle aches, weakness, and swollen lymph nodes (in neck, armpits and groin areas. Symptoms are followed by blisters that pop and crust over.

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The viral disease is believed to be spread to humans by domestic prairie dogs and other exotic animals being kept as household pets.

Since 2020, the WHO tracked 4,500 cases and 171 deaths attributed to monkeypox.

Three cases of the new strain have been confirmed in the US. Additionally, a White House official warned Sunday that more cases would likely emerge.

The White House official said no quarantine or other extreme measures are planned.

Health officials say monkeypox infection can be prevented by vaccines stockpiled from previous outbreaks.