Search

A larger number of publications on cases of. complicated vivax malaria in the world literature can be. explained by a set of diffeetit faciors'. There has been unification of the definition of complicated tertian malaria allowing ihe clinical nianagement of a patient and the reporting of complicated cases of P.vivax to be improved. The, epidemiological characteristics of complicated vivax malaria are determined by a diversity of geographical, races, variants, gentyies and phenotypes of tertian malaia due to intensive internal and external migration. Chloroquine resistance and primaquine refractoriness contribute to increased local malaria transmission due to a rise in cases of reinfection during-epidemics of vivax malaria. From an epidemiological point of view, the increasing number of complicated vivax malaria cases indicates the untimely detection and treatment of malaria patients, the low level of medical personnel training and a negative attitude of the local population towards the recommendations of national malaria programs for prevention measures. Unsolved problems can substantially retard the time to achieve malaria elimination.

The review presents the results of trials of the clinical efficacy of a test antimalarial drug for each malarial parasite species, which were published in 2000-2013 and supplemented by the data of in vitro studies or investigations using the molecular markers of resistance. There are data on the resistance of each medicament since many of the drugs are used in combination with artermisinin derivatives.

Early detection of imported cases of malaria and its prompt and efficacious treatment are one of the main tasks of health workers in malaria prevention during the post-elimination period. The diagnosis and treatment of malaria should be developed and standardized to prevent the re-emergence of local transmission from imported cases of malaria. Its diagnosis must be verified by only laboratory tests during the post-elimination period. Keeping in mind the possible rapid conversion of uncomplicated P. falciparum malaria into a several disease, these all cases should be managed in a hospital setting. The healthcare personnel dealing with the treatment of malaria should be aware of its clinical manifestations in non-immune residents and semi-immune immigrants. The main principles of malaria treatment are discussed in respect of age, sex, pregnancy, and different malaria species.

The details of imported case of Chesson strain of P. vivax malaria to Russian Federation (Moscow) from border areas between Myanmar and Thailand is given. It might further confirm the expansion of this strain from its original place in the Western Pacific towards other territories in the World, described in various publications.

The state-of-the-art of malaria elimination programs worldwide and the advances made in the past decade were analyzed and assessed. The factors contributing to or reducing the achievement of the final objective of malaria elimination--to interrupt the local transmission of the infection and to steadily maintain the achieved successes are given. Technical problems are defined at the final stages of a malaria elimination program. The problems include difficulties in identifying patients and asymptomatic parasite carriers due to the low level of malaria transmission and the absence of highly effective methods for detecting malaria parasites with low parasitemia, as well as mixed malaria infections requiring the use of different treatment regimens and antimalarial drugs. Large-scale uncontrolled population migration is noted to be of importance in spreading the infection in a malaria-free area. The solution of urgent tasks is to improve the existing methods and develop new ones for the detection and treatment of the infection and a package of antimalarial measures.

The major benefit of mass primaquine administration in the Republic of Azerbaijan and the Democratic People's Republic of Korea was a considerable reduction in malaria case load in the situation where there is acute inadequacy of various means for malaria control, as well as in the containment of a large-scale malaria epidemic caused exclusively by P. vivax in a relatively short period of time. Success of mass treatment can be achieved only through high coverage (about 90% of the target population), the elaboration of clear instructions for all categories of the personnel engaged in the treatment, with the provision of regular efficient supervision, the accessibility of first medical aid at the site in case of probable severe side effects. Adherence to these prerequisites results in the safety of the treated population with very high degree of G6PD deficiency.

The efficiency of P. vivax malaria treatment with delagil (chloroquine) was evaluated in 122 patients, including 82 cases in Moscow and the Moscow region. The origin of the cases was malaria endemic areas in Asia, Africa, the Pacific Region, South America, and Transcaucasia. Forty other cases were imported malaria cases (secondary to imported ones), detected in Moscow and the Moscow region. Standard treatment with delagil (2.5 g) resulted in clinical improvement during 3 days in the majority of cases. Initial signs of degradation of asexual stages of P. vivax--kernels of nucleus, refinement of cytoplasm and its vacuolization, aggregation of pigment in isolated instances, its pushing out from cytoplasm--were observed after 1-2 hours after administration of delagil. Thereafter, parasite degradation was increasing, and it disappeared within 48 hours. Disappearance of fever slowed down in a few cases. However, degradation of parasites occurred during the same period among the rest of cases. It can not be excluded that fever was determined by the pyrogenic effect of remnants of degraded parasites and by the products of destroyed infected erythrocytes. It is probable that the findings of gametocytes, not completely degraded after disappearance of asexual forms in conjunction with prolonged fever, could result in a wrong conclusion of drug resistance. Negative results of microscopy and nested PCR on the last day of treatment, as well as in the following 10 days and absence of complains during 45 days, suggest the absence of resistance to delagil in P. vivax strains imported from different regions of the world. It is also probable that the literature on P. vivax resistance to chloroquine is limited to sporadic cases.

The highest malaria morbidity rates have been observed in the Tajikistan's Khatlon Region that is contiguous with Afghanistan. This area is notorious for its high malariogenicity ("susceptibility" according to the WHO terminology), caused by natural climatic factors, as well as a significant vulnerability associated with socioeconomic conditions (intensive migration of populations among which there are many infected subjects). In children, tropical malaria is generally characterized by an acute onset, abnormal fever, and its polymorphism of clinical manifestations that are exemplified by the lack of typical malaria paroxysms, as well as a gradual progression of parasitemia during the first malaria attacks. Recurrences are induced by ineffective treatment and chloroquine resistance in the tropical malaria pathogen. The reduction in malaria morbidity has resulted from a package of large-scale malaria-controlling measures implemented with the support of the Global Fund to Fight AIDS, Tuberculosis, and Malaria.

The spectrum of Plasmodium vivax subpopulations could be evaluated by analyzing the results of experimental studies of late relapses in P. vivax malaria in north-western Delhi. The spectra of the subpopulations causing late recurrences were different for malaria with short-and longterm incubations. The conclusions previously made by mathematical stimulation as to that malaria with longterm incubation is mainly transmitted at the beginning of the season have been confirmed. Based on the results of the frequency analysis, 6 P. vivax subpopulations with the values of their development duration of 15, 240, 300, 390, 720, and 1020 days, respectively, were identified for formalization of an epidemic process.

The high incidence of malaria in Ethiopia is due to a number of natural and social factors. The 1988-1989 surveys of 525 patients among this country's indigenous population showed that its great proportion suffered from severe falciparum malaria, including that caused by the chloroquine-resistant strains Plasmodium falciparum. The severity of falciparum malaria seems to be determined by the low immunity of inhabitants in the hyperendemic areas and by late effective therapy. The lack of antimalarial drugs alternative to chloroquine will facilitate fatal malignant malaria.