Personally, I'd be quarantining myself from anyone who had recently been on an international flight, regardless of where they had been travelling. I'm more scared of the flu than tropical diseases and aircraft are the great incubators of the sky .
.
It's reasonable to be concerned as you are comprised, talk to your oncologist about the times in your chemo cycle that you are most at risk and what they think are sensible precautions for you to take. Seems a shame for your partner to miss his trip, there may be better or worse times for him to go.