I didn't get sick despite being rained on, despite fatigue, swollen feet and aching muscles due to endless walking and climbing stairs at various MTR stations. I had a secret weapon with me... ginger! I grated fresh ginger every night and every morning and made ginger ale using our hotel room's electric kettle. I brought a small grater and fresh ginger in my luggage. Even the BFF did not get sick. Aching muscles fully restored come morning.
Wow, I am so amazed by the power of the ginger.
On a totally unrelated subject, I'm wearing my favorite red shirt, as seen on my profile photo. I must have had that shirt for five years already. I will keep wearing it until it falls apart, ha ha ha. Or at least until I turn 40 in a few months.