Mass drug administration (MDA) involves the regular delivery of treatment medicines to whole populations, regardless of whether an individual has the disease or not, and aims to prevent onward transmission (passing from one person to another). It is currently recommended for some disease control programmes in low‐ and middle‐income countries, including the parasitic disease lymphatic filariasis, which can result in swollen limbs and disability. For governments and their health service this is a large logistical task requiring money and staff, and success depends on communities taking the medicines given. Read the full review