What happened

OraSure Technologies (OSUR -0.54%) is up 17.7% at 3:20 p.m. EDT following the release of its first-quarter earnings yesterday after the bell.

So what

Revenue increased 12% year over year, with OraQuick HCV sales increasing 111% as international sales more than quadrupled, thanks to a large order from a country doing large-scale testing to try and eliminate hepatitis C. OraSure's OraQuick HIV tests also had a solid 210% increase compared to the year-ago quarter, although the overall sales are smaller, so they don't contribute as much to the overall revenue growth. Sales of molecular collection systems, which is OraSure's largest segment, grew by a solid 55% year over year.

Earnings grew even faster than revenue, up from $0.04 per share in the year-ago quarter, to $0.21 in the first quarter of 2017. But much of the gain came from the inclusion of a $12.5 million pre-tax gain from the settlement of its dispute with Ancestry.com.

Paper with hepatitis C written on it with eye glasses resting on the paper.

Image source: Getty Images.

Now what

Management issued guidance for the second quarter, with revenue expected to fall in the range of $36.5 million to $37.0 million and consolidated net income of $0.07 to $0.08 per share.

Investors should keep an eye on sales of the OraQuick HCV test, which seems to be the company's growth driver at the moment. OraSure hopes that the unnamed country with the large OraQuick HCV order will renew its contract -- discussions are supposed to start this week. And management also noted that it had received orders from two other countries that plan to start large-scale hepatitis C testing programs.