By Adam Easton BBC Baltic region correspondent |

 TB can develop resistance to drugs |
Europe's first centre to fight the spread of multi-drug-resistant tuberculosis is opened in the Latvian capital Riga on Monday. It is a joint project between Latvia and the World Health Organisation.
New drug-resistant strains of TB are 100 times more expensive to treat than regular TB, and can often be fatal.
TB patients in eastern Europe are 10 times more likely to have a multi-drug-resistant strain of the disease than anywhere else in the world.
Chemotherapy
Normal TB is a global pandemic. But curing it is cheap and effective.
A six-month course of drugs costs about $10.
That is not the case with new strains of TB which are increasingly resistant to the treatment currently available.
Patients must take high-powered antibiotics or even extensive chemotherapy for up to two years.
And if a patient does not get the right drugs, in most cases it is fatal.
The World Health Organisation says 300,000 people around the world contract multi-drug resistant TB every year.
Aids threat
Many of them are in eastern Europe and central Asia.
That is why this centre, which will carry out research and develop a strategy to fight the spread of the disease, is based in Latvia.
And there is another reason. The region has among the highest infection rates for HIV/Aids in the world.
People who are HIV positive are more susceptible to all types of TB.
That is why Dr Jack Chow, the WHO's assistant director general for HIV/Aids, says multi-drug resistant TB must be defeated.
Because if the two diseases combine, he warns, both treatment costs and mortality rates could "sky-rocket".