Sarcocystosis -- one type of Coccidiosis

This excellent article was written with respect to birds of the parrot family, but it emphasises the fact that it's usually fatal only in pigeons and budgies.

http://www.vet.uga.edu/vpp/CLERK/rantze/index.php

Note that it is generally lethal only in the old world, where mortality is so fast that the birds don't even lose condition. This is attributed to the fact that in the Americas the definitive host, the opossum, lives alongside the affected birds, who develop some immunity.
This disease is spread by opossums, racoons, skunks, cockroaches, or cockroach droppings in badly-stored feed.

The symptoms are acute, fatal respiratory disease leading to pulmonary haemorrhage, lethargy and yellow urates.

Recommended treatment, to be administered by a vet: If S. falcatula infection is suspected or has been confirmed in a group of birds, anti-protozoal treatment is recommended with pyrimethamine (Daraprim) and trimethoprim sulfadiazine (Tribrissin). The suggested treatment protocol includes administration of pyrimethamine at 0.5 mg /kg body weight twice daily administered by gavage for 2 –4 days. The dosage of pyrimethamine is then reduced to 0.25 mg/kg for the next 30 days. Trimethoprim sulfadiazine is administered by intramuscular injection at a dosage of 5 mg/ kg body weight /day for seven days. Trimethoprim sulfadiazinemay cause muscle necrosis, especially in cockatoos. Therefore, continued oral treatment with the drug (30 mg /kg body weight per os every 12 hr for 30 days) would be a suitable alternative.12 Supportive care also is important and may include tube feeding by crop gavage, oxygen administration if dyspnea is present, and furosemide (1.6 mg/kg twice daily) to relieve pulmonary edema. This treatment protocol has been most effective in birds that are suspected to be infected with S. falcatula (e.g., the cagemate died of sarcocystosis) but are not showing clinical signs of disease.

Good article, Teresa.
Many thanks for sharing it with us.