RESUMO
The mechanism of chloroquine (CQ) resistance in Plasmodium falciparum is not clearly understood. However, CQ resistance has been shown to be associated with point mutations in Pfcrt and Pfmdr1. These genes encode for digestive vacuole transmembrane proteins Pfcrt and Pgh1, respectively. The present study was carried out to analyze the association of Pfcrt-K76T and Pfmdr1-N86Y mutations with CQ resistance in Northeast Indian P. falciparum isolates. 115 P. falciparum isolates were subjected to in vitro CQ sensitivity testing and PCR-RFLP analysis for the Pfmdr1-N86Y and Pfcrt-K76T mutations. 100 isolates of P. falciparum were found to be resistant to CQ by the in vitro susceptibility test (geometric mean EC50 2.21 µM/L blood) while 15 were found to be CQ sensitive (geometric mean EC50 0.32 µM/L blood). All the CQ resistant isolates showed the presence of Pfmdr1 and Pfcrt mutations. CQ sensitive isolates were negative for these mutations. Strong linkage disequilibrium was observed between the alleles at these two loci (Pfmdr1-N86Y and Pfcrt-K76T). The results indicate that Pfmdr1-N86Y and Pfcrt-K76T mutations can be used as molecular markers to identify CQ resistance in P. falciparum. The result necessitates the evaluation of CQ in vivo therapeutic efficacy in endemic areas for more effective malaria control strategies.
Assuntos
Marcadores Genéticos/genética , Malária/epidemiologia , Proteínas de Membrana Transportadoras/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Mutação de Sentido Incorreto/genética , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Cloroquina , Primers do DNA/genética , Resistência a Medicamentos/genética , Doenças Endêmicas , Índia/epidemiologia , Desequilíbrio de Ligação , Malária/prevenção & controle , Polimorfismo de Fragmento de RestriçãoRESUMO
A total of 550 stool samples were collected from a low socio economic population of Chandigarh (North India) and examined macroscopically and microscopically, to determine the prevalence of intestinal parasitic infections and their familial incidence. The overall prevalence rate was 19.3%. Ascaris lumbricoides and Giardia lamblia were the commonest, affecting 51 (9.3%) and 33 (6.0%), respectively. In 17 (22.7%) families the same parasite was observed to infect multiple family members, which included A.lumbricoides (in 9 families), G. lamblia (in 7 families) and H. nana (in 1 family). The results of present study indicate that there is a high prevalence of parasitic infection in the community where personal hygiene and sanitary conditions are poor and may be one of the contributing factors for transmission within the families. Intervention strategies including health education program should be designed and implemented to control parasitic infections.