Missing details about the death of a lab worker, including the cause, are worrying scientists. Russian authorities aren’t saying much about the death of a woman who worked in a lab studying plague. Key points and original sources are listed below.

• Missing details about the death of a lab worker, including the cause, are worrying scientists.S1

• Russian authorities aren’t saying much about the death of a woman who worked in a lab studying plague. But experts say any risk of contagion would be limited.S2

• Russian media identified victim as Darya Shipilova, 28, a laboratory worker at Irkutsk research centreS3