RESUMO
Recent molecular studies of chloroquine (CQ) resistance of Plasmodium falciparum have demonstrated an association between a mutation in the PfCRT gene and CQ resistance. We identified wild type and mutant alleles of the PfCRT codon 76 in baseline pre-CQ treatment P. falciparum isolates collected during 1999 and investigated their relationship to CQ efficacy in 3 different sites with different levels of CQ parasite resistance in Uganda. Of 32 isolates from Mulago Hospital, all were mutant (100%), while of 45 isolates from Tororo, 5 (11%) were mixed wild type and mutant and 40 (89%) were mutants only. Of 41 isolates from Apac, 13 (32%) were mixed wild type and mutant whereas 28 (68%) were mutants only. The finding of 100% prevalence of the Thr-76 mutant allele in all isolates at the 3 sites was remarkable. We found no association between the presence of Thr-76 mutation and treatment outcome at all the sites. However, the prevalence of the wild-type Lys-76 allele was higher in Apac, an area with lower CQ parasite resistance, compared to Tororo and Mulago which have relatively higher CQ parasite resistance. The Thr-76 allele as a marker of CQ resistance is probably useful in regions where the allele frequency has not yet plateaued.
Assuntos
Antimaláricos/uso terapêutico , Cloroquina/uso terapêutico , Malária Falciparum/genética , Proteínas de Membrana/genética , Mutação/genética , Plasmodium falciparum/genética , Animais , DNA de Protozoário/genética , Resistência a Medicamentos/genética , Genótipo , Humanos , Proteínas de Membrana Transportadoras , Plasmodium falciparum/efeitos dos fármacos , Reação em Cadeia da Polimerase/métodos , Proteínas de Protozoários , UgandaRESUMO
BACKGROUND: Chloroquine is a first line drug for the treatment of uncomplicated Plasmodium falciparum malaria in Uganda. Recently, there have been increasing reports of resistance of Plasmodium falciparum malaria to chloroquine, as well as an increase in malaria morbidity and mortality among adults and children. OBJECTIVES: To assess the current effectiveness (clinical and parasitological response) of chloroquine in the treatment of uncomplicated Plasmodium falciparum malaria, and to define the magnitude of chloroquine resistant Plasmodium falciparum malaria in Kampala. DESIGN: A descriptive cross-sectional study among adults and children. SETTING: Mulago hospital complex (the national referral and teaching hospital in Kampala, Uganda) between September 1998 and March 1999. RESULTS: Ninety six patients with Plasmodiumfalciparum parasitaemia of 1000 to 100,000/microl of blood were treated with oral chloroquine phosphate, and followed up for 14 days. Sixty three (65.6%) patients showed clinical improvement, 29 (30.2%) deteriorated and four (4.2%) had no change. Adequate parasitological response was seen in 71(74 %), moderate in four (4.2%) and poor in 21(21.8%) patients. Treatment failures were highest among children below five years, with eleven (57.9%) children not responding to chloroquine. CONCLUSION: Although chloroquine was found to be effective in two thirds of all patients, the high treatment failure, especially seen in children below five years is of concern. This necessitates further countrywide studies, and possibly a need to review the use of chloroquine as single first line drug for the treatment of uncomplicated malaria in Uganda, especially in children below five years of age.
Assuntos
Cloroquina/uso terapêutico , Resistência Microbiana a Medicamentos , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Humanos , Lactente , Pessoa de Meia-Idade , UgandaRESUMO
We explored observed risk factors and drivers of infection possibly associated with African swine fever (ASF) epidemiology in Uganda. Representative sub-populations of pig farms and statistics were used in a case-control model. Indiscriminate disposal of pig viscera and waste materials after slaughter, including on open refuse dumps, farm-gate buyers collecting pigs and pig products from within a farm, and retention of survivor pigs were plausible risk factors. Wire mesh-protected windows in pig houses were found to be protective against ASF infection. Sighting engorged ticks on pigs, the presence of a lock for each pig pen and/or a gate at the farm entrance were significantly associated with infection/non-infection; possible explanations were offered. Strict adherence to planned within-farm and community-based biosecurity, and avoidance of identified risk factors is recommended to reduce infection. Training for small-scale and emerging farmers should involve multidimensional and multidisciplinary approaches to reduce human-related risky behaviours driving infection.