On the last day of August the FDA granted emergency use authorisations for six Covid-19 tests from commercial manufacturers – five of them for viral RNA-based diagnostics and one for an antibody test – the most ever granted in a single day. Since the start of this month a few more authorisations have trickled out, the most recent being for Roche’s combined assay, capable of determining whether a patient has Covid-19 or flu – or both. The viral RNA test can also tell whether the patient has influenza A and/or influenza B. As the Northern hemisphere’s flu season approaches this kind of tech will be vital, enabling a one-shot diagnosis, including coinfections, rather than having to do sequential tests. The only other FDA-authorised panel that can simultaneously detect these viruses was developed by the Centers for Disease Control and launched in July. Roche can almost certainly manufacture more of them than the CDC can, though the Swiss group did not say exactly how many it intends to produce. Roche will surely soon receive another EUA for a Covid-19 test; its rapid antigen test was CE marked last week and the company is seeking authorisation in the US as well.