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1.
Arruda ME Zimmerman RH Souza RM Oliveira-Ferreira J 《Memórias do Instituto Oswaldo Cruz》2007,102(3):367-371
The aim of this study was to determine the prevalence of malaria infection and antibodies against the repetitive epitopes of the circumsporozoite (CS) proteins of Plasmodium falciparum, P. malariae, P. vivax VK210, P. vivax VK247, and P. vivax-like in individuals living in the states of Rond?nia, Pará, Mato Grosso, Amazonas, and Acre. Active malaria transmission was occurring in all studied sites, except in Acre. P. falciparum was the predominant species in Pará and Rond?nia and P. vivax in Mato Grosso. Infection by P. malariae was low but this Plasmodium species was detected in Rond?nia (3.5%), Mato Grosso (2.5%), and Pará (0.8%). High prevalence and levels of serological reactivity against the CS repeat peptides of P. falciparum were detected in Rond?nia (93%) and Pará (85%). Sera containing antibodies against the CS repeat of P. malariae occurred more frequently in Rond?nia (79%), Pará (76%), and Amazonas (68%). Antibodies against the repeat epitope of the standard CS protein of P. vivax VK210, P. vivax VK247, and P. vivax-like were more frequent in Rond?nia, Pará, and Mato Grosso. The high frequency of reactions to P. malariae in most of the areas suggests that the infection by this Plasmodium species has been underestimated in Brazil. 相似文献
2.
We performed a longitudinal study of adult survival of Anopheles darlingi, the most important vector in the Amazon, in a malarigenous frontier zone of Brazil. Survival rates were determined from both parous rates and multiparous dissections. Anopheles darlingi human biting rates, daily survival rates and expectation of life where higher in the dry season, as compared to the rainy season, and were correlated with malaria incidence. The biting density of mosquitoes that had survived long enough for completing at least one sporogonic cycle was related with the number of malaria cases by linear regression. Survival rates were the limiting factor explaining longitudinal variations in Plasmodium vivax malaria incidence and the association between adult mosquito survival and malaria was statistically significant by logistic regression (P<0.05). Survival rates were better correlated with malaria incidence than adult mosquito biting density. Mathematical modeling showed that P. falciparum and P. malariae were more vulnerable to changes in mosquito survival rates because of longer sporogonic cycle duration, as compared to P. vivax, which could account for the low prevalence of the former parasites observed in the study area. Population modeling also showed that the observed decreases in human biting rates in the wet season could be entirely explained by decreases in survival rates, suggesting that decreased breeding did not occur in the wet season, at the sites where adult mosquitoes were collected. For the first time in the literature, multivariate methods detected a statistically significant inverse relation (P<0.05) between the number of rainy days per month and daily survival rates, suggesting that rainfall may cause adult mortality. 相似文献
3.
Gametocytemia and fever in human malaria infections 总被引:2,自引:0,他引:2
We examine the charts of 408 malaria-naive neurosyphilis patients given malaria therapy at the South Carolina USPHS facility, with daily records encompassing at least 93% of the duration of infection, and focus on the 152 patients infected with the St. Elizabeth strain of Plasmodium vivax, 82 with the McLendon strain of Plasmodium filciparum, 36 with the USPHS strain of Plasmodium malariae, and 15 with the Donaldson strain of Plasmodium ovale in whom gametocytes appeared before drug, or other, intervention. In P. vivax infections, fever and parasitemia were higher after gametocytes were first detected than before; in P. malariae infections, parasitemia was higher. In P. ovale infections, fever and parasitemia were similar before and after. In P. falciparum infections, fever, parasitemia, and fever frequency were lower after gametocytes were first detected than before. Parasitemia and temperature correlated in P. vivax infections, before and after gametocytes were first detected; parasitemia and temperature at first fever were not correlated in infections with any species. Gametocyte density correlated with parasitemia in P. malariae and sporozoite-induced P. falciparum and P. vivax infections. Fevers and detected gametocytemia coincided more often than expected by chance with P. vivax and P. ovale; fever temperature and gametocyte density were not correlated in infections with any species. 相似文献
4.
Perandin F Manca N Galati L Piccolo G Calderaro A Viani I Ricci L Dettori G Chezzi C Turano A 《The new microbiologica》2001,24(1):69-76
A PCR method involving a genus-specific oligonucleotides set and Southern blot hybridization with four species-specific probes to P. falciparum, P. vivax, P. malariae and P. ovale was evaluated for the detection of malaria parasites in blood samples from 101 patients with clinically suspect malaria infection imported to Italy. Plasmodium falciparum was the main species detected. As determined by microscopy, 53 (52.4%) patients had malaria and of these: 40 (75.5%) were infected with P. falciparum; 7 (13.2%) with P. vivax; 1 (1.9%) with P. ovale; 3 (5.7%) with P. malariae; 1 (1.9%) with P. vivax or P. ovale; and 1 (1.9%) with P. falciparum or P. vivax. Ninety-seven out 101 blood samples were submitted to ParaSight-F test which showed a sensitivity of 94.73%, and a specificity of 93.22%, as compared to microscopy. The PCR assay using the genus-specific oligonucleotide primer set (pg-PCR) was able to detect 53 (52.4%) infections and showed a sensitivity of 100% and a specificity of 100%, when compared to microscopy. The parasite species were identified by Southern blot hybridization using species-specific probes and 40 (75.5%) samples were P. falciparum positive, 5 (9.4%) P. vivax positive, 4 (7.5%) P. ovale positive, and 2 (3.8%) P. malariae positive. When the Southern blot results were compared to those of blood-film diagnosis, we observed some disagreement. In particular, compared to Southern blot, microscopy underestimated P. ovale infection; blood film analysis recognised only 1 P. ovale sample, whereas Southern blot recognised 4 P. ovale positive samples (by microscopy, 2 of these were detected as P. vivax, 1 as P. ovale or P. vivax, and the other as P. falciparum or P. vivax). Southern blot hybridization was unable to identify one P. falciparum and one P. vivax positive case detected by microscopy. We also plan to use a reference nested-PCR assay to clarify the disagreement observed between microscopy and Southern blot hybridization. 相似文献
5.
da Silva AN Santos CC Lacerda RN Machado RL Póvoa MM 《Memórias do Instituto Oswaldo Cruz》2006,101(5):547-550
The susceptibility of Anopheles aquasalis (F3 generation) and An. darlingi (F1 generation) to Plasmodium vivax circumsporozoite protein phenotypes from a limited number of blood samples of malaria patients in Belém, state of Pará, Brazil, was examined A polymerase chain reaction was used to determine the P. vivax phenotypes in blood samples and the blood-fed infected mosquitoes were dissected and tested by ELISA. In all patient infections, more infected An. aquasalis and An. darlingi were positive for VK210 compared with VK247. 相似文献
6.
We conducted a survey to determine the vectors of malaria in six localities of Serra do Navio municipality, State of Amapá, from 1990 to 1991. Malaria infection rates of 29.3%, 6.2% and 20.4% were detected by human blood smears in Col?nia Agua Branca, Porto Terezinha and Arrependido, respectively. There was no malaria infection detected in Serra do Navio. Fifteen species were identified among 3,053 anopheline mosquitoes collected by human bait and 64.4% were identified as Anopheles albitarsis s.l., 16.7% An. braziliensis, 9.5% An. nuneztovari and 5.8% An. triannulatus. An. darlingi, the main vector of malaria in the Amazon region of Brazil, was scare. Using enzyme-linked immunosorbent assay (ELISA), a total positive rate of 0.8% (23/2876) was found for six species: fifteen An. albitarsis s.l., four An. nuneztovari, and one of each: An. braziliensis, An. triannulatus, An. oswaldoi and An. rangeli. Nine of 23 positive mosquitoes were infected with Plasmodium malariae, eight with P. vivax VK210, three with P. vivax VK247 and three with P. falciparum. Since An. albitarsis s.l. was collected feeding on humans, was present in the highest density and was positive by ELISA for malaria sporozoites, it probably plays an important role in malaria transmission in this area. 相似文献
7.
K Congpuong A Saejeng R Sug-Aram S Aruncharus A Darakapong SR Meshnick W Satimai 《Malaria journal》2012,11(1):288
ABSTRACT: BACKGROUND: Asymptomatic carriage of Plasmodium falciparum and Plasmodium vivax is common in both low-and high-transmission settings and represents an important reservoir of infection that needs to be targeted if malaria elimination is to succeed. METHODS: Mass blood examinations (475 individuals) were conducted in two villages in Mae Hong Son, an area of endemic but low-transmission malaria in the north-west of Thailand. The microscopist at the local malaria clinic did not detect any infections. Pools of four samples were screened by real-time PCR; individual members of all of the positive pools were then re-examined by expert microscopy and by a second species-specific PCR reaction. RESULTS: Eight subjects were found to be positive by both PCR and expert microscopy and one was found to be positive by PCR alone. The slides contained asexual stage parasites of P. vivax, P. falciparum and Plasmodium malariae, but no gametocytes. The local clinic was notified within two to eight days of the survey. CONCLUSION: A combination of pooling, real-time PCR and expert microscopy provides a feasible approach to identifying and treating asymptomatic malaria infections in a timely manner. 相似文献
8.
Manuela Herrera-Varela Lorena I Orjuela Cilia Pe?alver Jan E Conn Martha L Qui?ones 《Memórias do Instituto Oswaldo Cruz》2014,109(7):952-956
Malaria in La Guajira, the most northern state of Colombia, shows two different
epidemiological patterns. Malaria is endemic in the municipality of Dibulla whereas
in Riohacha it is characterised by sporadic outbreaks. This study aimed to establish
whether differences in transmission patterns could be attributed to different vector
species. The most abundant adult female species were Anopheles
aquasalis, exclusive to Riohacha, and Anopheles darlingi,
restricted to Dibulla. Anopheles mosquitoes were identified
using morphology and the molecular markers internal transcribed spacer 2 and
cytochrome c oxidase I. All specimens (n = 1,393) were tested by ELISA to determine
natural infection rates with Plasmodium falciparum and
Plasmodium vivax. An. darlingi was positive for P. vivax
210, with an infection rate of 0.355% and an entomological inoculation rate
of 15.87 infective bites/person/year. Anopheles albimanus larvae
were the most common species in Riohacha, found in temporary swamps; in contrast, in
Dibulla An. darlingi were detected mainly in permanent streams.
Distinctive species composition and larval habitats in each municipality may explain
the differences in Plasmodium transmission and suggest different
local strategies should be used for vector control. 相似文献
9.
We analyzed point-prevalence data from 19 recent studies of human populations in which either Plasmodium ovale or Plasmodium vivax co-occur with Plasmodium falciparum and Plasmodium malariae. Although the only statistical interactions among, sympatric congeners are pairwise, the frequencies of mixed-species infections relative to standard hypotheses of species sampling independence show no strong relation to overall malaria prevalence. The striking difference between the P. falciparum-P. malariae-P. ovale and the P. falciparum-P. malariae-P. vivax data is that the first typically shows a statistical surplus of mixed-species infections and the second a deficit. This suggests that the number of Plasmodium species present in a human population may be less important in determining the frequencies of mixed-species infections than is the identity of those species. 相似文献
10.
Although Plasmodium malariae was first described as an infectious disease of humans by Golgi in 1886 and Plasmodium ovale identified by Stevens in 1922, there are still large gaps in our knowledge of the importance of these infections as causes of malaria in different parts of the world. They have traditionally been thought of as mild illnesses that are caused by rare and, in case of P. ovale, short-lived parasites. However, recent advances in sensitive PCR diagnosis are causing a re-evaluation of this assumption. Low-level infection seems to be common across malaria-endemic areas, often as complex mixed infections. The potential interactions of P. malariae and P. ovale with Plasmodium falciparum and Plasmodium vivax might explain some basic questions of malaria epidemiology, and understanding these interactions could have an important influence on the deployment of interventions such as malaria vaccines. 相似文献
11.
Robert V Le Goff G Andrianaivolambo L Randimby FM Domarle O Randrianarivelojosia M Raharimanga V Raveloson A Ravaonjanahary C Ariey F 《International journal for parasitology》2006,36(12):1273-1281
Malaria transmission remains poorly documented in areas of low transmission. A study has been carried out over two consecutive years in Analamiranga, a village located at an altitude of 885m on the western edge of the Malagasy highlands, with the aim of generating and updating malariometric indexes for both mosquitoes and schoolchildren. In this village, no vector control measures were performed during the study period nor during previous decades. Mosquitoes were collected monthly when landing on human volunteers and in various resting-places. Blood samples were taken every 3 months from schoolchildren aged 6-12 years and microscopically examined. Of 7,480 mosquitoes collected on human subjects, 5,790 were anophelines. Ten anopheline species were represented and three of these, Anopheles funestus, Anopheles arabiensis and Anopheles mascarensis, accounted for 59.2% of the collection. Of these three species 4,640 were also collected in resting places. The proportion of mosquitoes fed on bovids was high; conversely, the anthropophilic rate (mosquitoes fed on human beings) was especially low: 31%, 7% and 1%, respectively, for A. funestus, A. arabiensis and A. mascarensis. The only confirmed malaria vector was A. funestus with a low sporozoite index (of 6,830 A. funestus, five were positive for Plasmodium falciparum and four for Plasmodium vivax). The annual entomological inoculation rate (number of bites of infected anophelines per adult person) was estimated at 2.49 with low variation over the 2 years. Overall, 909 thick blood smears were tested from blood samples taken from schoolchildren with 30.3% being malaria-positive. The four Plasmodium species infecting human subjects were detected in the following proportions: P. falciparum 78.9%, P. vivax 19.4%, Plasmodium malariae 1.0% and Plasmodium ovale 0.7%. The proportions of children who were infected with any Plasmodium ranged from 10.7% in February to 51.0% in September. Parasitemic children with fever (axillary temperature >37.5 degrees C) accounted for 16.4% of the children sampled. This study demonstrates that there are substantial parasitological consequences of even a relatively low entomological transmission and also recommends including exterior resting-places of mosquitoes in future spraying campaigns in the highlands of Madagascar. 相似文献
12.
AR Bharti S Saravanan V Madhavan DM Smith J Sharma P Balakrishnan SL Letendre N Kumarasamy 《Malaria journal》2012,11(1):306
ABSTRACT: BACKGROUND: Malaria and HIV co-infection adversely impact the outcome of both diseases and previous studies have mostly focused on falciparum malaria. Plasmodium vivax contributes to almost half of the malaria cases in India, but the disease burden of HIV and P. vivax co-infection is unclear. METHODS: HIV-infected subjects (n=460) were randomly selected from the 4,611 individuals seen at a Voluntary Counseling and Testing Center in Chennai, India between Jan 2 to Dec 31 2008. Malaria testing was performed on stored plasma samples by both nested PCR using both genus-specific and species-specific primers and immunochromatography-based rapid diagnostic test for detecting antibodies against both Plasmodium falciparum and P. vivax. RESULTS: Recent malaria co-infection, defined by the presence of antibodies, was detected in 9.8% (45/460) participants. Plasmodium vivax accounted for majority of the infections (60%) followed by P. falciparum (27%) and mixed infections (13%). Individuals with HIV and malaria co-infection were more likely to be men (p=0.01). Between those with and without malaria, there was no difference in age (p=0.14), CD4+ T-cell counts (p=0.19) or proportion CD4+ T-cell below 200/mL (p=0.51). CONCLUSIONS: Retrospective testing of stored plasma samples for malaria antibodies can facilitate identification of populations with high rates of co-infection, and in this southern India HIVinfected cohort there was a considerable burden of malaria co-infection, predominantly due to P. vivax. However, the rate of P. falciparum infection was more than 6-fold higher among HIV-infected individuals than what would be expected in the general population in the region. Interestingly, individuals co-infected with malaria and HIV were not more likely to be immunosuppressed than individuals with HIV infection alone. 相似文献
13.
Nacher M Singhasivanon P Gay F Silachomroon U Phumratanaprapin W Looareesuwan S 《The Journal of parasitology》2001,87(4):912-915
Following an investigation suggesting a protective role for Ascaris against cerebral malaria, possibly through immunomodulation, we examined whether Ascaris had any impact on mixed Plasmodium falciparum and Plasmodium vivax infections. We studied a cross section of 928 patient files between 1991 and 1999. Forty patients had contemporaneous mixed infections and 40 patients had P. falciparum infections, followed by P. vivax infections. There was a significant association between Ascaris infection and risk of having both contemporaneous or successive mixed P. falciparum and P. vivax infections (adjusted odds ratios respectively 6 [2-18] P = 0.001 and 3.6 [1.2-11.1] P = 0.02). There was a positive linear trend between the burden of Ascaris and the risk of mixed infections P < 0.0001. These results suggested the possibility that pre-existing Ascaris infection may increase tolerance of the host to different Plasmodium spp., thus facilitating their coexistence. 相似文献
14.
Malaria transmission potential of Anopheles mosquitoes in the Mwea-Tebere irrigation scheme, Kenya 总被引:1,自引:0,他引:1
1. Anopheles arabiensis Patton and An. funestus Giles were identified as vectors of Plasmodium falciparum malaria in the Mwea-Tebere irrigation scheme, Kenya. An. arabiensis was the only member of the An. gambiae complex identified from chromosome characteristics. Other Anopheles species found included An. pharoensis Theobald, An. rufipes Gough and An. coustani Laveran. Survival rates per gonotrophic cycle for An. arabiensis averaged 0.37 during the short rains (October-November), 0.49 during the dry season (February) and 0.78 during the long rains (May-June). Vectorial capacities were correspondingly low due to low survival rates and a high degree of zoophily. The average duration of infective life for P. falciparum was 0.2 days for both An. arabiensis and An. funestus. In contrast, entomological inoculation rates were comparatively high: 6-8 infective bites/man/month. An. pharoensis averaged 110 bites/man/night during the short rains; 1/999 (0.1%) was positive by ELISA for P. falciparum circumsporozoite antigen, but the ELISA evidence is not conclusive for vector incrimination. In correspondence with clinical observations, the transmission of P. malariae and P. ovale is unlikely due to the low vector survival rates. The observed anomaly between low vectorial capacities and high entomological inoculation rates demonstrates the importance of accurately estimating vector sporozoite rates to monitor unstable malaria transmission in irrigated areas. 相似文献
15.
16.
Angélica Domingues Hristov Maria Carmen Arroyo Sanchez José Jarbas Bittencourt Ferreira Giselle Fernandes Maciel de Castro Lima Juliana Inoue Maria de Jesus Costa-Nascimento Arianni Rondelli Sanchez Eduardo Milton Ramos-Sanchez Silvia Maria Di Santi 《Memórias do Instituto Oswaldo Cruz》2014,109(8):1014-1020
Studies on autochthonous malaria in low-transmission areas in Brazil have acquired
epidemiological relevance because they suggest continued transmission in what remains
of the Atlantic Forest. In the southeastern portion of the state of São Paulo,
outbreaks in the municipality of Juquitiba have been the focus of studies on the
prevalence of Plasmodium, including asymptomatic cases. Data on the occurrence of the
disease or the presence of antiplasmodial antibodies in pregnant women from this
region have not previously been described. Although Plasmodium falciparum in pregnant
women has been widely addressed in the literature, the interaction of Plasmodium
vivax and Plasmodium malariae with this cohort has been poorly explored to date. We
monitored the circulation of Plasmodium in pregnant women in health facilities
located in Juquitiba using thick blood film and molecular protocols, as well as
immunological assays, to evaluate humoural immune parameters. Through real-time and
nested polymerase chain reaction, P. vivax and P. malariae were detected for the
first time in pregnant women, with a positivity of 5.6%. Immunoassays revealed the
presence of IgG antibodies: 44% for ELISA-Pv, 38.4% for SD-Bioline-Pv and 18.4% for
indirect immunofluorescence assay-Pm. The high prevalence of antibodies showed
significant exposure of this population to Plasmodium. In regions with similar
profiles, testing for a malaria diagnosis might be indicated in prenatal care. 相似文献
17.
Calderaro A Piccolo G Zuelli C Galati L Ricci L Perandin F Dell'Anna ML Arcangeletti MC Medici MC Manca N Dettori G Chezzi C 《The new microbiologica》2004,27(2):163-171
A new molecular diagnostic method "Malaria-IBRIDOGEN" (Amplimedical S.p.A.--Bioline Division, Turin, Italy) based on a plate-hybridization assay for the simultaneous detection and identification of human malaria parasites was evaluated in this study. A target DNA sequence of the plasmodial 18S ribosomal RNA gene was amplified by polymerase chain reaction (PCR) and hybridized in microtiter wells with five biotinylated probes each specific for Plasmodium falciparum, P. vivax, P. malariae, P. ovale and the beta-globine human gene, respectively. Compared to the nested-PCR actually used in our laboratory for the molecular diagnosis of malaria, "Malaria-IBRIDOGEN" revealed an overall sensitivity of 100% (51/51) for the four human Plasmodium species testing 100 whole blood samples from people with malaria-like symptoms and fever. Specificity was 92% (45/49) considering four discordant samples as "false positive" by "Malaria-IBRIDOGEN". The assay showed a threshold of parasite density (detection limit) of 0.07 P. falciparum parasites/microliter, 0.15-1.5 P. vivax parasites/microliter, 0.3 P. malariae parasites/microliter and 0.4 P. ovale parasites/microliter of whole blood, respectively. This assay could be successfully applied to the laboratory diagnosis of malaria as a useful aid to microscopy. 相似文献
18.
ABSTRACT: BACKGROUND: Malaria remains a significant health problem in Bangladesh affecting 13 of 64 districts. The risk of malaria is variable across the endemic areas and throughout the year. A better understanding of the spatial and temporal patterns in malaria risk and the determinants driving the variation are crucial for the appropriate targeting of interventions under the National Malaria Control and Prevention Programme. METHODS: Numbers of Plasmodium falciparum and Plasmodium vivax malaria cases reported by month in 2007, across the 70 endemic thanas (sub-districts) in Bangladesh, were assembled from health centre surveillance reports. Bayesian Poisson regression models of incidence were constructed, with fixed effects for monthly rainfall, maximum temperature and elevation, and random effects for thanas, with a conditional autoregressive prior spatial structure. RESULTS: The annual incidence of reported cases was 34.0 and 9.6 cases/10,000 population for P. falciparum and P. vivax respectively and the population of the 70 malaria-endemic thanas was approximately 13.5 million in 2007. Incidence of reported cases for both types of malaria was highest in the mountainous south-east of the country (the Chittagong Hill Tracts). Models revealed statistically significant positive associations between the incidence of reported P. vivax and P. falciparum cases and rainfall and maximum temperature. CONCLUSIONS: The risk of P. falciparum and P. vivax was spatially variable across the endemic thanas of Bangladesh and also highly seasonal, suggesting that interventions should be targeted and timed according to the risk profile of the endemic areas. Rainfall, temperature and elevation are major factors driving the spatiotemporal patterns of malaria in Bangladesh. 相似文献
19.
Evolutionary origin of human and primate malarias: evidence from the circumsporozoite protein gene 总被引:8,自引:1,他引:7
We have analyzed the conserved regions of the gene coding for the
circumsporozoite protein (CSP) in 12 species of Plasmodium, the malaria
parasite. The closest evolutionary relative of P. falciparum, the agent of
malignant human malaria, is P. reichenowi, a chimpanzee parasite. This is
consistent with the hypothesis that P. falciparum is an ancient human
parasite, associated with humans since the divergence of the hominids from
their closest hominoid relatives. Three other human Plasmodium species are
each genetically indistinguishable from species parasitic to nonhuman
primates; that is, for the DNA sequences included in our analysis, the
differences between species are not greater than the differences between
strains of the human species. The human P. malariae is indistinguishable
from P. brasilianum, and P. vivax is indistinguishable from P. simium; P.
brasilianum and P. simium are parasitic to New World monkeys. The human P.
vivax-like is indistinguishable from P. simiovale, a parasite of Old World
macaques. We conjecture that P. malariae, P. vivax, and P. vivax-like are
evolutionarily recent human parasites, the first two at least acquired only
within the last several thousand years, and perhaps within the last few
hundred years, after the expansion of human populations in South America
following the European colonizations. We estimate the rate of evolution of
the conserved regions of the CSP gene as 2.46 x 10(-9) per site per year.
The divergence between the P. falciparum and P. reichenowi lineages is
accordingly dated 8.9 Myr ago. The divergence between the three lineages
leading to the human parasites is very ancient, about 100 Myr old between
P. malariae and P. vivax (and P. vivax-like) and about 165 Myr old between
P. falciparum and the other two.
相似文献
20.
Duarte AM Porto MA Curado I Malafronte RS Hoffmann EH de Oliveira SG da Silva AM Kloetzel JK Gomes Ade C 《Journal of medical primatology》2006,35(2):87-96
BACKGROUND: A survey of malaria antibodies was carried out over 7 years and a total of 777 serum samples from wild monkeys were collected in three distinct ecological areas of Brazil where autochthonous malaria has been reported: the 'Cerrado' (similar to savanna), the Atlantic Forest and the Atlantic Semideciduous Forest. METHODS: We carried out enzyme-linked immunosorbent assay to investigate the presence of IgG antibodies against peptides of the circumsporozoite protein (CSP) repeat region of 'classic'Plasmodium vivax, P. vivax VK247, human P. vivax-like/P. simiovale, P. brasilianum/P. malariae and P. falciparum. We also carried out immunofluorescence assay with asexual forms of P. vivax, P. malariae and P. falciparum. RESULTS: The high prevalence of antibodies against CSP in all areas indicates that the monkeys had intense contact with sporozoites from infected anophelines. The immune response against asexual forms of Plasmodium in the monkeys from the Atlantic Forest indicates the development of the infection. CONCLUSIONS: We discuss the possibility of monkeys being malaria reservoirs in non-endemic areas. 相似文献