Large populations brought together in evacuation centers may contract diseases through poor sanitation. Some evacuees may suffer mental stress and other psychological disorders related to displacement, and violence is also common.
Widespread ashfall or gas impact (acid rain) may lead to agricultural hardships including crop failure, loss of livestock and contamination of water supplies which, in turn, may trigger famine and related diseases. Livestock may starve due to smothering of feed and/or if feeding is impaired due to excessive tooth wear as ash is highly abrasive. Ingestion of ash can also cause fatalities due to intestinal blockages.
Heavy ashfall can cause roof collapse and is also slippery, making clean-up and driving hazardous. Infrastructure may be impacted, affecting primary healthcare responses.