PCR detection of lizard malaria parasites: prevalence of Plasmodium infections with low-level parasitemia differs by site and season.
Plasmodium-specific polymerase chain reaction (PCR) primers allowed detection of infections with very low-level parasitemia for 3 species of malaria parasites infecting Anolis lizards at 2 Caribbean sites, Puerto Rico and Saba, Netherlands Antilles. A verification study, using a single-tube nested PCR to eliminate contamination, showed that infections as low as 1 parasite per millions of erythrocytes could be detected by amplifying a 673 bp fragment of the cytochrome b gene. Very low-level parasitemia infections, subpatent under the microscope, were common in A. sabanus on Saba sites, with no significant seasonal difference (31% of infections appearing uninfected by microscopic examination in summer were found infected by PCR, 38% in winter). At the Puerto Rico site, the subpatent infections were also common in A. gundlachi, but were more prevalent in winter (53%) than in summer (17%). A similar high frequency of subpatent infections is known from studies on human and bird malaria, but a previous PCR-based study on a temperate lizard malaria system found few such low-level infections. Differences in the prevalence of subpatent infections by site and season suggest transmission biology may select for distinct life history strategies by the parasite.
Department of Biology, University of Vermont, Burlington 05405, USA.
Anne M
AM
Vardo
Andrew R
AR
Wargo
Jos J
JJ
Schall
D000818:Animals; D016054:DNA, Protozoan / Q000097:blood; D005260:Female; D008116:Lizards / Q000469:parasitology*; D008288:Malaria / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary*; D008297:Male; D009427:Netherlands Antilles / Q000453:epidemiology; D018512:Parasitemia / Q000453:epidemiology / Q000662:veterinary*; D010961:Plasmodium / Q000235:genetics / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction / Q000592:standards / Q000662:veterinary*; D015995:Prevalence; D011647:Puerto Rico / Q000453:epidemiology; D012621:Seasons; D012680:Sensitivity and Specificity
D016054:DNA, Protozoan