You don't need an air filter to operate over the jungle, or even the desert on a calm day. You do need an air filter to operate from up-paved air strips IN the jungle and IN the desert, unless those strips are sodded with fine English grass. The Germans had a cute and effective trop filter with a clam shell door in front, and P-38 Lightnings sucked air through a filter when the undercarriage was lowered. Those Hurricanes that operated over Burma were generally based in India.
Did the UK make any attempt to copy these ideas?