Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Plasmodium malariae”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2006

Report of a case of congenital malaria Plasmodium malariae in France.

Congenital malaria (CM) has been considered to be rare, even in malaria-endemic areas but the disease can result in significant neonatal morbidity. Because of its rarity, the disease may go undiagnosed for a prolonged period in a seriously ill infant. We report the first case of Plasmodium malariae CM from a HIV mother. HIV could have facilitated the transfer of erythrocytic persistent P. malariae through the placenta to the fetus.

Adult↗
PubMed2006

Characterization and application of multiple genetic markers for Plasmodium malariae.

Plasmodium malariae, a protozoan parasite that causes malaria in humans, has a global distribution in tropical and subtropical regions and is commonly found in sympatry with other Plasmodium species of humans. Little is known about the genetics or population structure of P. malariae. In the present study, we describe polymorphic genetic markers for P. malariae and present the first molecular epidemiological data for this parasite. Six microsatellite or minisatellite markers were validated using 76 P. malariae samples from a diverse geographical range. The repeat unit length varied from 2 to 17 bp, and up to 10 different alleles per locus were detected. Multiple genotypes of P. malariae were detected in 33 of 70 samples from humans with naturally acquired infection. Heterozygosity was calculated to be between 0.236 and 0.811. Allelic diversity was reduced for samples from South America and, at some loci, in samples from Thailand compared with those from Malawi. The number of unique multilocus genotypes defined using the 6 markers was significantly greater in Malawi than in Thailand, even when data from single genotype infections were used. There was a significant reduction in the multiplicity of infection in symptomatic infections compared with asymptomatic ones, suggesting that clinical episodes are usually caused by the expansion of a single genotype.

Alleles↗
PubMed2002

Rapid immunochromatographic malarial antigen detection unreliable for detecting Plasmodium malariae and Plasmodium ovale.

In order to determine the reliability of two commercial tests for the rapid detection of plasmodial antigen in cases of infection with Plasmodium ovale and Plasmodium malariae, the products were evaluated in four centers and a search of the relevant literature was performed. The results of the present and previous studies were compared. With overall sensitivities ranging between 18.8% and 47.6% for Plasmodium malariae and between 20% and 31.3% for Plasmodium ovale, it is evident that neither test is reliable for the detection of Plasmodium ovale and Plasmodium malariae infections.

Animals↗
PubMed1988

In vitro cultivation of exoerythrocytic stages of the human malaria parasite Plasmodium malariae.

Exoerythrocytic stage parasites of Plasmodium malariae were obtained in vitro by inoculating primary cultures of hepatocytes from a chimpanzee (Pan troglodytes) and a monkey (Aotus lemurinus griseimembra) with sporozoites. Schizonts were observed in chimpanzee hepatocytes 8, 11, and 13 days after inoculation. Only 1 schizont was seen in Aotus hepatocytes at day 13. The morphology and development rates of P. malariae exoerythrocytic stages obtained in vitro were similar to those previously described in vivo.

Animals↗
PubMed1998

High prevalence of Plasmodium malariae and Plasmodium ovale in malaria patients along the Thai-Myanmar border, as revealed by acridine orange staining and PCR-based diagnoses.

The prevalence of the four human malaria parasites was investigated among malaria patients at northern, central and southern towns in Thailand along the border with Myanmar between September 1995 and May 1996. Thin smears obtained from 548 Thai and Burmese patients were reviewed by an acridine orange staining method, and many mixed infections with two to four species, including P. malariae and P. ovale, were detected. These diagnostic results were compared with those by two PCR-based diagnoses, microtitre plate hybridization (MPH) and a nested PCR method, both of which targets the same, species-specific regions in the 18S rRNA genes. In both PCR diagnoses, many P. malariae and P. ovale infections were also detected. Detection sensitivity of P. malariae infection was higher in nested PCR than MPH, and a total prevalence of P. malariae infection estimated by nested PCR reached 24.3% (133/548). In 16 of them, the size of PCR products amplified by the P. malariae-specific primer was about 20-bp shorter than the expected size of 115-bp. Four of 16 possessed two different bands with normal and shorter sizes, suggesting that P. malariae isolates may be separated into two types, and that those with shorter products may be new variant form (s) with a nucleotide deletion in the target region. On the other hand, 21 P. ovale infections (3.8%) were detected by nested PCR, but four of them were MPH-negative because of the sequence variation at the probe region. These results indicated that the prevalence of P. malariae and P. ovale along the Thai-Myanmar border may be substantially higher than previously reported.

Acridine Orange↗
PubMed1993

Experimental infection of Anopheles gambiae s.s., Anopheles freeborni and Anopheles stephensi with Plasmodium malariae and Plasmodium brasilianum.

Susceptibility to infection of 2 strains of Anopheles gambiae s.s., An. freeborni and An. stephensi, was determined for 2 closely related malaria parasites, Plasmodium malariae and P. brasilianum. Neither strain of An. gambiae supported development of oocyst densities as great as the other 2 anopheline mosquitoes. The ZAN strain of An. gambiae s.s. from Zanzibar was more susceptible to infection with the strain of P. malariae from Uganda than the G-3 strain of An. gambiae s.s. from The Gambia. All species and strains of mosquitoes supported complete development to the presence of sporozoites in the salivary glands.

Animals↗
PubMed1999

The blood-stage dynamics of mixed Plasmodium malariae-Plasmodium falciparum infections.

We present the first mathematical model of the within-host dynamics of a mixed-species malaria infection in a human: the blood-stage population dynamics of a dual infection with Plasmodium malariae and Plasmodium falciparum. Our results reproduce several important features of such infections in nature, including the asymmetry of species asexual-form densities, inter-specific suppression through interactions with the human immune system, and seasonal alternations in species prevalence. Most importantly, our results suggest that an existing P. malariae infection can reduce the peak parasitemia of a subsequent P. falciparum superinfection by as much as 50%. This result integrates numerous empirical observations and supports the hypothesis that clinical outcomes of P. falciparum infections may be influenced by the presence of a congener.

Animals↗
PubMed2000

[Congenital malaria due to Plasmodium falciparum and Plasmodium malariae].

Increasing tourism and growing numbers of immigrants from malaria-endemic countries are leading to a higher importation rate of rare tropical disorders in European countries. We describe, to the best of our knowledge, the first case of connatal malaria in Austria. The patient is the first child of a 24 year old mother who was born in Ghana and immigrated to Austria one and a half years before delivery. She did not stay in an endemic region during this period and did not show fever or any other signs of malaria. The boy was healthy for the first six weeks of his life. In the 8th week of life he was admitted to our hospital due to persistent fever of unknown origin. On physical examination he showed only mild splenomegaly. Routine laboratory testing revealed mild hemolytic anemia with a hemoglobin value of 8.3 g/l. In the blood smear Plasmodium falciparum and Plasmodium malariae were detected. Oral therapy with quinine hydrochloride was successful and blood smears became negative for Plasmodia within 6 days. This case shows that congenital malaria can occur in children of clinically healthy women who were born in malaria-endemic areas even one and a half year after they have immigrated to non-endemic regions.

Adult↗
PubMed2002

Plasmodium malariae infection boosts Plasmodium falciparum gametocyte production.

We analyzed records of malaria therapy patients sequentially or simultaneously inoculated with Plasmodium falciparum and Plasmodium malariae. Gametocyte production was enhanced in P. falciparum by prior or concurrent P. malariae infection but diminished or unaffected in P. malariae by P. falciparum. Conversely, asexual-form production was diminished in P. malariae but unaffected in P. falciparum.

Animals↗
PubMed1980

A malaria outbreak due to Plasmodium malariae on the Island of Grenada.

An outbreak of Plasmodium malariae malaria occurred in Grenada some 16 years after the end of a malaria eradication campaign, probably due to renewal of transmission from recrudescent cases. Serological studies were used in addition to blood film surveys in defining the outbreak, and their value in such surveillance situations is emphasized.

Adolescent↗
PubMedDate not supplied

Reappearance of Plasmodium malariae in Suriname?

Plasmodium malariae has not been reported from Suriname since 1979. In 1989 an increasing number of P. vivax infections among Bush-negroes returning from the eastern part of the interior was reported in Paramaribo. A microscopical re-examination of all malaria cases in the eastern part of the country failed to confirm any P. vivax infections, but instead P. malariae infections were diagnosed. A study followed to determine the Duffy blood group antigens of 4 Bush-negroes allegedly with a P. vivax infection in their medical history and of 28 and 32 unselected Bush-negroes and Amerindians respectively. Three of the 4 former Bush-negroes had the FyB antigen, while only 7% of the unselected Bush-negroes had this antigen. This low frequency of the genotype is incompatible with reports of high P. vivax prevalences in Bush-negro populations. The Amerindians tested showed a low proportion of Fy0 genotype, which is compatible with the frequent diagnosis of P. vivax among this ethnic group. Reports of P. vivax infections among Bush-negroes are due to misdiagnosis of P. malariae, emphasizing the need to include all 4 species of human Plasmodium when (re)training microscopists. The question whether P. malariae reappeared in Suriname due to increased contact with the simian reservoir, or was simply missed, is discussed.

Animals↗
PubMed2002

Congenital malaria as a result of Plasmodium malariae--North Carolina, 2000.

Congenitally acquired malaria is rare in the United States; < or = 10 cases are reported each year. Congenital infection with Plasmodium malariae is particularly uncommon because distribution of this parasite is focal and sparse in areas where P. falciparum is endemic. The last case of congenital P. malariae infection in the United States was reported in 1992. This report describes the investigation of a case of P. malariae in an infant with no travel history outside of the United States and suggests that health-care providers suspect malaria when treating a neonate or young infant with fever if the mother has traveled or lived in a malarious area.

Animals↗
PubMed2005

[Congenital malaria as a result of Plasmodium malariae in an infant born to a HIV-seropositive woman].

Congenital malaria is uncommon in France. The purpose of this report is to describe a case involving a six-week-old infant who was hospitalized with fever, hepatosplenomegaly, anemia and thrombopenia. Thick and thin blood smears were positive for Plasmodium malariae. The infant responded favorably to chloroquine. Based on this experience, we performed a search of the literature to find case reports on congenital malaria in France and compare clinical and epidemiologic data with series reported in the United States and from endemic areas. The placenta appears to provide an effective barrier against Plasmodium since infection is much more common than disease. The delay for onset of clinical symptoms is longer in temperate zones than in endemic areas. The type of parasite could account for this difference since African congenital malaria are due to Plasmodium falciparum while most cases described in the United States are due to Plasmodium vivax. We also discuss the possible implications of coinfection by HIV in the mother.

Antimalarials↗