The Diamed "OptiMAL-IT" test is a malaria test kit designed for use in human patients. However, since it uses monoclonal antibodies against the metabolic enzyme pLDH (parasite lactate dehydrogenase) found in Plasmodium species, it can theoretically be used to test blood from non-human patients as well.

The susceptibility of outdoor exhibited captive penguins and certain other avian species to malaria is well documented. Current techniques for diagnosis include direct examination of blood smears (which requires an experienced haematologist) and histopathology (usually performed on samples collected at post mortem examination, with a turn-around of several days). An indirect fluorescent antibody test (IFAT) is also available, but may not indicate active infection unless used in series, and a polymerase chain reaction test (PCR) for Plasmodium species is not widely available in the UK. In a zoological collection holding susceptible species, a quick, inexpensive diagnostic test for malaria that could be performed "in-house" would be very useful. This report describes validation of the "OptiMAL-IT" test in two bird species kept at Bristol Zoo Gardens.

An African penguin (Spheniscus demersus) that died in August 2004 and another that died in August 2006 both tested positive for plasmodium pLDH, using the "OptiMAL-IT" test on blood samples taken at post mortem examination. Both penguins were confirmed to have protozoal schizonts of Plasmodium species present in liver, lung and spleen on histopathology. Other penguins of this species that tested negative with the "OptiMAL-IT" test on post mortem blood samples were confirmed as negative for Plasmodia on histopathology.

An Inca tern (Larosterna inca) that died in October 2007 tested positive for plasmodium pLDH using the "OptiMAL-IT" test on a post mortem blood sample. Inclusions in red blood cells similar in morphology to a Plasmodium species were seen in a blood smear made prior to death, and plasmodial schizonts were identified in heart, liver, kidney, spleen and lung on post mortem histopathology. Blood from a live Inca tern treated for an injury in October 2007 tested negative for plasmodium pLDH using the "OptiMAL-IT" test. This blood sample was confirmed to be free of Plasmodia on examination of a smear by a haematologist.

These results suggest that the "OptiMAL-IT" test can be used to test for malaria in some avian species. Further work is needed to validate the test for use in other avian species.