Its a fact. People living next to each other will ultimately facilitate reinfection of trees kept in good condition. Its the same situation for children in childcare. Citrus trees are prone to something called bronze orange bug (BOB) or ‘stink bugs’. These are sap sucking insects. They suck the sap from new shoots and cause tip dieback, stops flowering, and retards health / vigour.
Thats the bad news. The good news is that they can’t ‘sting’ us. However some safety precautions need to be met and exceeded. They have a spray that gets into human eyes and causes a horrible reaction. Its extremely painful, and can cause temporary blindness. Safety glasses are recommended to shield the operator from this malady. Secondly they spray stains skin, and can cause irritation to cuts (and of course citrus spines create scratches, plus the irritation can be rather painful). Gloves are recommended, and fine tuned ones, to permit dexterity of your fingers.
Methods are easy to control these bugs; simply pick them off and put them into a jar of water with a splash (10 – 20 mL) of dish detergent. Once there are too many bugs in the detergent, pick them out (dont worry! they cannot bite you!) and put them into a larger jar.
Done! Repeat in a week, and again a week again and monitor.