Covid-19 is a respiratory virus.

 The virus is thought to spread mainly from person-to-person:

Between people who are in close contact with one another (within about 6 feet).

Through respiratory droplets produced when an infected person coughs or sneezes.

These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs.

Spread from contact with infected surfaces or objects.

You can find up to date health information here –https://www.nhs.uk/conditions/coronavirus-covid-19/

And current guidelines on how ceremonies may take place here – https://www.gov.uk/government/publications/covid-19-guidance-for-small-marriages-and-civil-partnerships/covid-19-guidance-for-small-marriages-and-civil-partnerships 

This is a developing situation however and the advice may change.