RESUMO
The main objective of this paper is to make available in a single document, a sequence of events that have been published on the biology of malaria parasites and their interaction with the human host, looking for arguments for effective and save treatment: what we know and what we would like to know about the effects of primaquine in order to justify its use in clinical and public health practice. The practicioner should be aware that the antimalarial activity, hemolytic and methemoglobinemic side effects, and detoxification of primaquine are all thought to depend on various biotransformation products of the drug. In spite of the universal use during over six decades, their site and mechanism of formation and degradation and their specific biologic effects remain very poorly understood in human beings. The mature gametocytes of P. falciparum are naturally resistant to chloroquine and other blood merontocides, but they are usually eliminated with a single dose of 1.315 mg/kg per os (p.o.) of primaquine phosphate (equivalent to 0.75 mg-base). Rather than empirically, related with relapses frequency, dosage schedules should only be determined through consideration of the kinetics and dynamics of the drug and its effect on sporozoites, pre and exo-erythrocytic merontes, hypnozoites and gametocytes of P. vivax. Where medical care services are not available or not capable to detect glucose-6-phosphate dehydrogenese- (G-6-PD) deficiencies and deleterious effects of the drug, we recommend not to use primaquine. Both, P. vivax primary clinical attack and P. vivax relapses, as and when they occur should be treated with a course of 10 mg/kg chloroquine-base p.o. Prevention of relapses is probably related to strain characteristics of P. vivax hypnozoites populations involved. If well informed and qualified medical care workers decide to use primaquine in the absence of enzime deficiencies and are able to follow-up the clinical, toxicological and parasitic results, a daily dose of 0.25 mg/kg primaquine-base during 14 days could be administered safety for possible prevention of P. vivax relapses.
Assuntos
Antimaláricos/farmacologia , Malária Falciparum/tratamento farmacológico , Malária Vivax/tratamento farmacológico , Primaquina/farmacologia , Animais , Antimaláricos/farmacocinética , Cloroquina/farmacologia , Humanos , Malária Falciparum/parasitologia , Malária Vivax/parasitologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium vivax/efeitos dos fármacos , Primaquina/farmacocinética , RecidivaRESUMO
The activities of several beta-lactam antimicrobial agents, aminoglycosides and ciprofloxacin, were determined against 62 clinical isolates of enterobacteria resistant to oxyimino cephalosporins (extended-spectrum beta-lactamase producers), collected during 1991 to 1993, and 16 penicillin-resistant invasive isolates of Streptococcus pneumoniae collected during 1994-1996. The numbers and percentages of susceptible enterobacterial strains to tested antibiotics were: imipenem 60 (97%), ciprofloxacin 57 (92%), cefepime 56 (90%), cefpirome 34 (55%), aztreonam 13 (21%), cefotaxime 7 (11%), ceftazidime 0 (0%), amikacin 11 (18%) and gentamicin 16 (26%). Despite the fact that these strains had never been exposed previously to cefepime or cefpirome, the susceptibility was 90% and 55%, respectively. No penicillin-resistant strains of S. pneumoniae were susceptible to cefotaxime, imipenem or cefepime. Only one strain was susceptible to ceftazidime and 4 (25%) were susceptible to cefpirome. Erythromycin showed the greatest activity with 12 (75%) susceptible strains.
Assuntos
Antibacterianos/farmacologia , Resistência às Cefalosporinas , Enterobacteriaceae/efeitos dos fármacos , Resistência às Penicilinas , Streptococcus pneumoniae/efeitos dos fármacos , Aminoglicosídeos , Anti-Infecciosos/farmacologia , Ciprofloxacina/farmacologia , Contagem de Colônia Microbiana , México , beta-Lactamases/metabolismo , beta-LactamasRESUMO
Parasite diseases such as Leishmaniases and American Trypanosomiases have been increasingly important in Mexico and other countries of the American Region. In known areas, these diseases are highly endemic, and in recently opened developing areas became a new threat to public health. Some social groups working in natural resources exploitation, agriculture, animal stock and public labor are particularly affected. The molecular epidemiology approach to these diseases is linking valuable capabilities and resources within the academic and operational institutions actual working in genetic polymorphism, strain characterization and PRC identification of Trypanosoma and Leishmania parasites. Clinical and epidemiological aspects of American trypanosomiasis infections and Chagas's disease and of cutaneous, mucocutaneous, disseminated and visceral leishmaniases, as well as genetic susceptibility studies have been initiated by Mexican scientists. In order to organize and coordinate the molecular epidemiology activities and support effective prevention and control programs against these diseases, political decision from the health, and academic authorities is urgently needed to adopt and support the research strategy for typing Trypanosoma and Leishmania species through exposition and biological markers (analysis of chromosomal DNA, ribosomal genes restriction patterns, DNA sequence, and DNA plasmids); the study of the membrane proteins and isoenzymes and monoclonal antibodies; detecting antigens and nucleic acids; defining susceptibility to infection with genetic markers, and searching for species, variants and mutant strains responsible for high virulence. The support for the establishment of a Reference Center for identification, cryopreservation and registration of parasites, vectors and reservoires is of paramount importance.
Assuntos
Doença de Chagas/epidemiologia , Leishmaniose/epidemiologia , Animais , Bancos de Espécimes Biológicos , Doença de Chagas/genética , Doença de Chagas/prevenção & controle , DNA de Protozoário/genética , Reservatórios de Doenças , Suscetibilidade a Doenças , Variação Genética , Planejamento em Saúde , Humanos , Insetos Vetores/parasitologia , Agências Internacionais , Leishmania/classificação , Leishmania/genética , Leishmania/isolamento & purificação , Leishmaniose/genética , Leishmaniose/prevenção & controle , México/epidemiologia , Camundongos , Prevalência , Sistema de Registros , Especificidade da Espécie , Transferência de Tecnologia , Trypanosoma cruzi/classificação , Trypanosoma cruzi/genética , Trypanosoma cruzi/isolamento & purificação , VacinaçãoRESUMO
Malaria and other arthropod born diseases remain a serious public health problem affecting the lives and health of certain social groups when the two basic strategies to control fail due to: (1) the lack of effective chemoprophylaxis/chemotherapy or the rapid development of drug resistance of the infectious agents and (2) the ineffectiveness of pesticides or the arthropod vectors develop resistance to them. These situations enhances the need for the design and implementation of other alternatives for sustainable health programmes. The application of the epidemiological methods is essential not only for analyzing the relevant data for the understanding of the biological characteristics of the infectious agents, their reservoirs and vectors and the methods for their control, but also for the assessment of the human behaviour, the environmental, social and economic factors involved in disease transmission and the capacity of the health systems to implement interventions for both changes in human behaviour and environmental management to purpose guaranteed prevention and control of malaria and other arthropod born diseases with efficiency, efficacy and equity. This paper discuss the evolution of the malaria and arthropod diseases programmes in the American Region and the perspectives for their integration into health promotion programs and emphasis is made in the need to establish solid basis in the decision-making process for the selection of intervention strategies to remove the risk factors determining the probability to get sick or die from ABDs. The implications of the general planning and the polices to be adopted in an area should be analyzed in the light of programme feasibility at the local level, in the multisectoral context of specific social groups and taking in consideration the principles of stratification and equity.
Assuntos
Vetores Artrópodes , Malária/prevenção & controle , Animais , Países em Desenvolvimento , Planejamento em Saúde , Promoção da Saúde , Humanos , Controle de Insetos , América Latina , Malária/epidemiologia , Malária/transmissão , Modelos Teóricos , Programas Nacionais de Saúde , Saúde Pública , Fatores de Risco , Fatores Socioeconômicos , Organização Mundial da SaúdeRESUMO
Malaria and other arthropod born diseases remain a serious public health problem affecting the lives and health of certain social groups when the two basic strategies to control fail due to : (1) the lack of effective chemoprophylaxis/chemotherapy or the rapid development of drug resistance of the infectious agents and (2) the ineffectiveness of pesticides or the arthropod vectors develop resistance to them. These situations enhances the need for the design and implementation of other alternatives for sustainable health programmes. The application of the epidemiological methods is essential not only for analyzing the relevant data for the understanding of the biological characteristics of the infectious agents, their reservoirs and vectors and the methods for their control, but also for the assessment of the human behaviour, the environmental, social and economic factors involved in disease transmission and the capacity of the health systems to implement interventions for both changes in human behaviour and environmental management to purpose guaranteed prevention and control of malaria and other arthropod born diseases with efficiency, efficacy and equity. This paper discuss the evolution of the malaria arthropod diseases programmes in the American Region and the perspectives for their integration into health promotion programs and emphasis is made in the need to establish solid basis in the decision-making process for the selection of intervention strategies to remove the risk factors determining the probability to get sick or die from ABDs. The implications of the general planning and the polices to be adopted in an area should be analyzed in the light of programme feasibility at the local level, in the multisectoral context specific social groups and taking in consideration the principles of stratification and equity
Assuntos
Malária/epidemiologia , Vetores Artrópodes/epidemiologia , Malária/prevenção & controle , Vetores Artrópodes/prevenção & controleRESUMO
The sensitivity of Plasmodium falciparum to antimalarial drugs is primarily determined by observing changes in the level of parasitaemia after administration of drugs to man. Performance of such a study and interpretation of its results may present certain difficulties, especially when conducted among persons living in malarious areas. The present study was conducted to evaluate the usefulness of a simple in vitro method for detecting chloroquine-resistant strains among infected residents of Mato Grosso, Brazil. The findings indicated the participants were infected with chloroquine-resistant P. falciparum. Subsequent administration of a standard regimen of chloroquine (25 mg/kg) to these subjects confirmed the findings observed in vitro by failing to cure 28 out of 30 infections. This in vitro technique seems to provide a useful method of determining the presence or prevalence of chloroquine-resistant strains in a given area.