ABSTRACT
Heart worm is a major potentially life-threatening disease of dogs in Thailand, spread through mosquito biting. Because of Thailand is located in tropical zone, mosquitoes proliferate easily. All dogs living in a heavily populated mosquito area are at risk. It is possible that most dogs in endemic foci could be at risk for heartworm new infection and reinfection every year. Dogs may not show signs of illness until the disease is severe. Through surveys, the high prevalence of Dirofilaria immitis infection has been shown be evident in the stray and pet dogs. Humans are accidental and deadend hosts of dirofilariae because adults worms do not reach maturity in the heart. Most infective larvae injected into humans are thought to perish; therefore, infected individuals usually are not microfilaremic. Human disease is amicrofilaremic; although, because human disease is an accidental event, only one degenerate immature larva or young adult worm usually is isolated from an ectopic position of the body. Human infection presents with either subcutaneous nodules or lung parenchymal disease that may be asymptomatic. The significance of infection in humans is that pulmonary lesions and some subcutaneous lesions are commonly labeled malignant tumors, requiring invasive investigation and surgery before a correct diagnosis is made. The interruption of the transmission cycle and the reduction of mosquitos’ population play an important role in the controlling of dirofilariasis. More over, a final line of defense for this disease is the prevention of mosquito bites in both human beings and animals.
ABSTRACT
This study aimed to separate crude proteins of Plasmodium gallinaceum antigen (PgAg) by SDS-PAGE and detect reactive antigens with infected chicken sera by Western blot. Antigen was prepared from 80% parasitized chicken blood, differentially centrifuged to separate parasite cells from frozen lysed red blood cells. The parasite cells were sonicated and centrifuged. The soluble crude PgAg samples were separated and analyzed into protein bands with SDS-PAGE. Several proteins of blood-stage extract were in the molecular-weight (MW) range 22-205 kDa, with some protein bands at higher and lower MWs than the standard proteins. By Western-blot analysis, PgAg-blotted membranes reacted with sera from inoculated chickens with blood stage Pg; chickens in an endemic area diagnosed with malaria by symptoms and positive ELISA; chickens with malaria symptoms in a fresh-poultry market, and other diseases; a blood protozoan (Leucocytozoon sabrazesi) co-infected with other parasites; a coccidian (Eimeria tenella); and Newcastle virus, including negative serum. The results showed 2 malarial protein bands, ie, 32.5 kDa reacted with all Pg-inoculated sera, and some positive sera by ELISA and endemic area. Another antigen was MW 72 kDa, with all Pg-inoculated sera and endemic sera, but not with ELISA-positive sera. This study showed that malaria-infected chickens produced specific antibodies against two interesting avian malaria antigens, of MW 32.5 and 72 kDa, which can be used in Western blot detection.