On a mission? Wear a mask

In the no-good-deeds-go-unpunished category, 20 volunteers from mission groups in Pennsylvania and Virginia who helped renovate a church in El Salvador earlier this year fell ill with a fungal disease called histoplasmosis.

The fungus, Histoplasma capsulatum, is found in soil, especially soil that's been contaminated by bird or bat droppings. If inhaled, it can cause acute respiratory illness.

The outbreak was written up in Thursday's Morbidity and Mortality Weekly Report, published by the national Centers for Disease Control and Prevention.

The 20 volunteers were among 34 people from three mission groups who traveled to Nueva San Salvador, El Salvador, last January and February for a week to replace a church roof, tinker with plumbing and generally spruce up the place. Those whose jobs included digging or sweeping were the most likely to fall ill, probably because they disturbed the soil and caused microscopic fungal spores to become airborne.

Symptoms, which began about 12 days after exposure, included fever, fatigue, headaches and chills. Six of the volunteers were hospitalized. All recovered.

The fungus can be found in soil throughout the world, including the United States, especially around chicken coops and bird roosts. Most people who become infected have only mild symptoms and recover without treatment. Construction workers and farmers, who are most at risk, are advised to wear respirators and to spray water to keep dust down.

Good-deed doers can do the same.

-- Mary Engel