My wife has been exposed to someone who tested positive for covid-19 and she's pregnant. she got in contact with person at work for about 2 hours?

COVID 19 exposure : If you were near your wife keep isolated, your wife needs to keep isolated. She should get tested and speak to her gynecologist

COVID 19 exposure: Recommend that she quarantine and advised her obstetrician. In South Africa a medical provider will determine need for COVID 19 testing. Consult your local primary care provider or you can use telemedicine for individual consultations. There are a number of free apps to look at your risk.