Here is the translation of the expanded content into English:

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According to RIA Novosti, a virus of unknown origin has emerged in Russia. Although there is no specific data on the number of cases or hospitalizations, the reported infections are not isolated. While the number of cases is currently not high, the appearance of this unknown virus has raised concern among health authorities and the public.

Those infected with this virus initially experience weakness and body aches, but after just a few days, their condition worsens significantly: they may develop a high fever up to 39°C (102.2°F), become bedridden, and cough up blood. One patient reported that even after several days of taking medication, the coughing persisted, with no improvement. However, tests for COVID-19 and acute respiratory infections still came back negative, leaving doctors increasingly puzzled as they try to determine the cause of the illness.

Doctors and medical experts have not yet identified the specific virus or its origin. Preliminary analysis suggests that this virus may have different transmission characteristics compared to known viruses, but there is still insufficient data to make a definitive conclusion. Health experts are continuing to investigate new cases, trying to understand the virus's properties and develop an effective treatment method.

Furthermore, many specialists believe that this virus could be linked to new environmental factors or possibly a variant of an already existing virus. Doctors have recommended calling emergency services if a person's condition deteriorates quickly, especially if symptoms such as coughing up blood or prolonged high fever appear. Local authorities are also stepping up monitoring and controlling high-risk areas and preparing response measures in case the outbreak spreads.

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