A high-security laboratory on a small island in northern Germany is producing some of the deadliest viruses in the world.

The Friedrich Loeffler Institute breeds highly dangerous diseases and bacteria, including bird flu, foot-and-mouth disease, Ebola, and mad cow disease.

The work is so dangerous that the only route to access the island is by a dam, which can be closed off at any time in case of an outbreak.

Researchers at the institute are particularly interested in "zoonoses," infectious diseases that can spread from humans to animals and vice versa.

The lab is the most modern animal disease research institute in Europe.

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Sprawling blue water, small cottages, and green reeds gently swaying in the wind: Travelers who get lost on Riems, a small German island in the Baltic Sea, could easily mistake it for a holiday destination. But the idyllic surroundings are deceptive. If you walk a bit further into the island, you are suddenly confronted by high walls and barbed wire. Behind these barriers is a research laboratory facility that is classified as one of the most dangerous in the world, according to the Federation of American Scientists.

Whoever wants to visit the laboratory — which is also partly underground — needs a special permit, protective clothing, and a shower. This is because the researchers working inside are responsible for national as well as international disease control. Highly dangerous viruses and bacteria are bred here, including bird flu, foot-and-mouth disease, Ebola, and mad cow disease, according to the institute's website.

The Friedrich Loeffler Institute, otherwise known as the National Institute for Animal Health in Germany, is a research center that mainly focuses on studying animal diseases, many of which can be fatal for humans.

This is why the very small island, which is located in the most northern part of Germany, can only be reached via a dam — so that in the case of an outbreak, it can be quickly closed off and isolated.

The research laboratory first opened in 1910 and has been growing ever since. Getty

A growing facility

The researcher Friedrich Loeffler founded the institute in 1910 to study foot-and-mouth disease, eventually becoming the first person to discover that the deadly disease was viral.

The small two-storey wooden hut in which Loeffler carried out his experiments thereby became the world's first research institute studying virology.

When Loeffler moved his work to the Robert Koch Institute in Berlin in 1913, research on the island came to a standstill. But in 1926, the laboratory reopened and was later used for the construction of bioweapons during the Second World War. Several years later, during the Cold War, scientists used the facility to develop vaccines.

The facilities also include 163 stables, where scientists can carry out tests on larger animals. Getty

From 1992 onwards, the institute became the National Institute for Animal Health in Germany.

On its 100th anniversary, $288 million was invested by the government and it expanded to become the most modern animal disease research institute in Europe. In 2010, several Biosafety level 4 laboratory facilities were added, which allow research to be done on the most dangerous of viruses.

The new building consists of 89 laboratories as well as 163 stables, which allow scientists to carry out tests on larger animals. Researchers at the institute are particularly interested in "zoonoses," infectious diseases that can spread from humans to animals and vice versa. These include malaria, tapeworm, rabies, and the plague. After all, almost two-thirds of infectious diseases are spread to humans from animals.

Anyone who leaves the high-security laboratory must be very careful to ensure that nothing they came into contact with reaches the outside world. But there is never a guarantee. In 2007, a foot-and-mouth virus from The Pirbright Institute for Animal Health in Surrey, England infected the animals on a neighboring farm through a leaky drainpipe. This incident makes one thing very clear: you are never really safe on one of the most dangerous islands in the world.