PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “malaria”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original 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
PubMed2026

Malaria Risk among Internally Mobile Individuals and Heterogeneous Mobility Patterns in Two Hypoendemic Communities: Implications for Malaria Elimination in the Peruvian Amazon.

BACKGROUND: Human mobility is increasingly recognized as a key factor influencing malaria transmission dynamics, particularly in low-transmission settings approaching elimination. This study aimed to assess mobility patterns and their association with malaria risk in two hypoendemic communities in the Peruvian Amazon. METHOD: A longitudinal study was conducted in the communities of Libertad and Urcomira&#xf1;o (Maz&#xe1;n River basin). Monthly population screenings were combined with weekly active and passive case detection. A total of 678 individuals were enrolled. Mobility patterns were assessed through structured questionnaires, and social network analysis was used to characterize travel connections. Log-binomial regression analysis was applied to identify risk factors associated with malaria infection. RESULT: Internally, mobile individuals in Libertad showed a higher malaria incidence (>32.47 cases per 1,000 person-months) than those in Urcomira&#xf1;o (<10.15 cases per 1,000 person-months). Travel networks were mainly connected to Mazan district and Iquitos city, followed by local streams such as Armas and Arahuana. Mobility was primarily driven by family, administrative and occupational activities. Male sex (PR = 2.15, 95% CI: 1.37 - 3.37) and age &#x2265;15 years (PR = 1.98, 95% CI: 1.24 - 3.19) were significantly associated with malaria infection (p-value < 0.05). CONCLUSION: Internally mobile populations represent a key high-risk group sustaining malaria transmission in hypoendemic settings. Targeted interventions focusing on mobile individuals should be integrated into malaria elimination strategies in the Peruvian Amazon and similar endemic regions.

Malaria elimination↗
PubMed2026

Malaria-GENOMAP: a web-based tool for exploring genomic variation of malaria parasites.

MOTIVATION: Malaria, caused by Plasmodium parasites, imposes a significant public health burden. While Plasmodium falciparum remains the primary target of elimination strategies due to its high mortality rate, lesser-known species such as P. malariae, P. vivax, and P. knowlesi continue to contribute to substantial human morbidity. Genomic approaches, including whole-genome sequencing, offer powerful tools for understanding the biology, transmission, and emerging drug resistance of these neglected Plasmodium species. However, there is an urgent need for informatic tools to summarize and visualize the high-dimensional and complex genomic data generated. RESULTS: We developed Malaria-GENOMAP, a user-friendly web-based tool, which integrates genomic variant data, such as allele frequencies, with geographical maps and chromosome-wide to gene views for in-depth exploration. The tool includes variation from P. knowlesi (n&#x2009;=&#x2009;139), P. malariae (n&#x2009;=&#x2009;158), P. ovale curtisi (n&#x2009;=&#x2009;36), P. ovale wallikeri (n&#x2009;=&#x2009;47), P. simium (n&#x2009;=&#x2009;38), and P. vivax (n&#x2009;=&#x2009;1359). It enables the investigation of population structure, geographic associations of mutations, and putative drug resistance markers, offering valuable insights for malaria control efforts. AVAILABILITY AND IMPLEMENTATION: Malaria-GENOMAP is available online at https://genomics.lshtm.ac.uk/malaria-genomaps.

Internet↗
PubMed1979

Free-flow electrophoresis for the separation of malaria infected and uninfected mouse erythrocytes and for the isolation of free parasites (Plasmodium vinckei): a new rapid technique for the liberation of malaria parasites from their host cells.

After aggregation of erythrocytes from malaria infected mice, the parasites (Plasmodium vinckei) could be set free using gentle mechanical forces. The mixture of freed parasites, infected and non-infected erythrocytes, and membraneous material was separated by free-flow electrophoresis. The free parasites produced were very pure and infectious. Morphological and enzymatic data on the separated fractions are presented. Free-flow electrophoresis also allowed the separation of infected and uninfected erythrocytes.

Animals↗
PubMed1977

The seroepidemiology of malaria in Middle America. IV. Passage of malaria antibodies from mothers to infants.

In an area of El Salvador moderately endemic for malaria, use of the indirect fluorescent antibody test (IFA) showed that 44% of the infants born to mothers who had IFA responses to Plasmodium vivax of 1:20 or higher during the latter part of their pregnancy had positive IFA responses of 1:10 or higher to this antigen. No serum from an infant was positive in the absence of some level of malarial response in the mother.

Antibodies↗
PubMed1979

[Malaria hypothesis--the significance of the hereditary red cell traits Hb S and glucose-6-phosphate dehydrogenase deficiency in malaria (author's transl)].

The high frequencies of the Hb S and G6PD-deficiency genes in the tropics are explained by their relative resistance against malarial infection. They may confer advantage through lower infection rates or through lower parasitaemia. There is evidence that heterozygote carriers of these genes are partially protected. The mechanism of resistance is known for Hb S but not completely understood for the G6PD-deficiency gene. Other red cell factors are discussed with respect to innate resistance against malaria.

Adult↗
PubMed2026

Malaria driven mechanisms shaping cancer risk and aggressiveness in African populations.

Malaria and cancer represent intersecting public health challenges in sub-Saharan Africa, where malaria remains endemic and cancer incidence is rapidly increasing. Emerging evidence indicates that chronic or recurrent malaria infection may influence carcinogenesis and tumour aggressiveness through complex biological mechanisms. This narrative review critically synthesizes data from PubMed, Scopus, and Web of Science to elucidate the mechanistic intersections between malaria and cancer risk, progression, and therapeutic response. The review highlights five principal axes linking malaria to oncogenesis: malaria-induced oxidative stress and chronic inflammation driving genomic instability; gut microbiome dysbiosis altering systemic immunity and tumour microenvironment; exploitation of shared molecular targets such as the endothelial protein C receptor (EPCR) and oncofetal chondroitin sulfate by Plasmodium parasites and cancer cells; cooperative interactions between malaria and oncogenic viruses like Epstein-Barr virus in lymphomagenesis; and malaria-associated vitamin D deficiency impairing immune surveillance. Furthermore, pharmacological evidence reveals that several antimalarial agents, including artemisinin derivatives, chloroquine, and quinacrine, possess anticancer properties, while some anticancer drugs exhibit antimalarial activity, underscoring opportunities for dual-action or repurposed therapeutics. The convergence of malaria and cancer biology underscores the urgent need for integrative, multidisciplinary research spanning molecular epidemiology, immunology, and pharmacology. Unveiling these mechanisms may unveil novel biomarkers and therapeutic targets, guiding context-specific interventions to reduce the disproportionate cancer burden in malaria-endemic African populations.

Humans↗
PubMed1977

Malaria in the Republic of the Philippines. A review.

Malaria in the Republic of the Philippines is caused principally by P. falciparum and P. vivax, with the former as predominant species. P. malariae is occasionally reported, while P. ovale is very rare and has been reported only in the island of Palawan. Malaria is widespread in distribution with prevalence varying from one area to the other. In 1970, the malaria morbidity rate was reported to be 77.6 per 100,000 while the mortality rate was 1.8 per 100,000. Case detection activities revealed that, in 1973, the slide parasite rate was 7.2%, the annual parasite index was 6.1% and the annual blood examination rate was 8.4%. The principal vector of malaria in the Philippines is An. minimus flavirostris which breeds in clear, fresh-water streams in foothills and mountain slopes. An. mangyanus and An. maculatus appear to play a secondary role. The vectorial capacity of the former appears to be confined only where conditions are primitive, while the latter is associated with malaria transmission in high altitudes. In the absence of fresh-water streams, the salt-water breeder mosquito, An. litoralis, assumes the vectorial role. The epidemiology of malaria in the Philippines is discussed. Emergence of strains of P. falciparum with diminished sensitivity to the commonly used antimalarial drugs is reported in Palawan and Rizal provinces. The development of malaria control activities in the Philippines are presented. As of 1972, Cagayan Valley, Palawan, Mindoro, Sulu and circumscribed areas in Mindanao are still considered hard-core malarious areas with on-going persistent transmission.

Animals↗
PubMed1979

Immunity to malaria.

Malaria remains prevalent throughout tropical and subtropical regions and almost a third of the World's population is exposed to the risk of infection. There is currently a serious resurgence of the disease in Asia and Central America. The failure of global eradication measures based upon the use of insecticides and chemotherapy has resulted from difficulties of practical implementation compounded by the spread of insecticide and drug resistance. Repeated natural infection does not produce detectable resistance to the exo-erythrocytic cycle of malaria in man. Irradiated sporzoite vaccines do, however, induce stage specific immunity in murine malaria and in a proportion of human subjects. Vaccinated individuals remain susceptible to blood stage infection which causes clinical malaria. In addition the vaccine is unstable and must be administered by intravenous inoculation. Since neither sporogonic nor exo-erythrocytic parasite development is cyclical in human malarias, there is little prospect for vaccine production through cultivation of these stages. The inhabitants of hyperendaemic areas become increasingly resistant to malaria during childhood and adolescence, through the slow development of specific, acquired immunity to asexual blood stage parasites. Immunity is mediated by antibody, which blocks merozoite invasion of red cells, as well as by cell mediated mechanisms and non-specific cytotoxic agents. Vaccination with merozoites induces long lasting immunity of broad serological specificity active against the blood-stage of the parasite. Merozoite vaccines can be preserved by freeze drying and harvested from continuous cultures of blood stage parasites. The major problem in development of a human merozoite vaccine concerns the requirement for Freund's complete adjuvant which is not acceptable for man. The effective immunity induced by vaccination contrasts with the slow development of incomplete resistance which follows repeated natural infection. The latter is associated with the generation of immune suppressor cells, lymphoid cell mitogens and soluble antigens, and in some species by the occurrence of antigenic variation--all of which may favour parasite survival. It is probable that vaccination with non-viable antigen of appropriate composition, induces immune effector processes without activating mechanisms which allow parasites to escape the consequences of immunity. Many effective vaccines such as those against measles, poliomyelitis, tetanus and rabies are commercially available but barely used in the developing world. The affected nations cannot afford their purchase, nor do the means exist for their distribution. It follows that if a safe and effective malaria vaccine were to be developed, its bulk manufacture and administration would require massive international support and cooperation.

Animals↗
PubMed1977

An outbreak of introduced malaria in California possibly involving secondary transmission.

During 1974, 12 cases of Plasmodium vivax malaria were reported from an agricultural area in California's Sacramento Valley. At least three of these cases resulted from local mosquito transmission. The imported cases were in Punjabi immigrants except for one in an American-born visitor to the Punjab. This is the 11th reported outbreak of introduced malaria in the United States since 1952, and the first in California since 1957. A unique aspect of this outbreak is the likelihood that secondary transmission occurred. Extensive surveillance activities, including a house-to-house case-finding survey in a 15-square-kilometer area of suspected transmission, yielded no new malaria cases, but the activities may have increased awareness of malaria among both the medical community and the public, and thus facilitated the detection of later cases. The occurrence of local malaria transmission coincided with unusually high numbers of Anopheles freeborni. The increase in imported malaria cases probably reflects a resurgence of malaria in Punjab State, India.

Adolescent↗
PubMed2026

Malaria rapid diagnostic tests: performance, pitfalls, and progress.

PURPOSE OF REVIEW: Malaria rapid diagnostic tests (RDTs) have revolutionized malaria diagnosis in endemic settings. RDTs are simple to use and accurate for clinical cases, although sensitivity is reduced at parasite densities below 200&#x200a;parasites/&#x3bc;l. However, increasing prevalence of hrp2/3 gene deletions in certain areas threaten utility of histidine-rich protein 2 (HRP2)-based RDTs, and lingering HRP2 antigenemia can generate false-positive results after parasite clearance. This review summarizes current performance of malaria RDTs, threats to their validity, and recent innovations to improve their performance and continued role in malaria diagnosis. RECENT FINDINGS: Most World Health Organization (WHO) prequalified RDTs perform well for clinical diagnosis, with only occasional exceptions, including a recently reported issue affecting several countries. RDT sensitivity is generally related to malaria transmission intensity, with higher proportions of false-negative results in lower-transmission areas. Newly prequalified lactate dehydrogenase (pLDH)-based RDTs perform well for both Plasmodium falciparum in areas with >5% hrp2/3 gene deletions&#xa0;and for Plasmodium vivax diagnosis. Several point-of-care alternatives to RDTs, including micro-fluidic devices, hemozoin-detecting devices, and automated hematology analyzers, have shown promising results in small studies, but require larger-scale trials before widespread use. SUMMARY: RDTs remain a critical tool in clinical diagnosis of malaria, and newer pLDH-based tests perform well in areas where hrp2/3 gene deletions threaten validity of HRP2-based RDTs.

Humans↗
PubMed1979

[Congenital malaria in a Greek twin (author's transl)].

A case of congenital malaria due to Plasmodium malariae in one of two living Greek twins born in Germany is presented. In the child fever, anaemia and hepatosplenomegaly were first noticed at the age of two months. Plasmodium malariae parasites were demonstrated in the peripheral blood and bone marrow. The sera of mother and infant contained malaria antibodies. However the mother never showed clinical signs of malaria. Diagnosis and therapy of congenital malaria and the possible mode of transmission of this rare disease are discussed.

Anemia↗
PubMed1979

Abnormal haemoglobins in the Sudan savanna of Nigeria. III. Malaria, immunoglobulins and antimalarial antibodies in sickle cell disease.

Subjects with sickle cell disease were identified in (i) a whole population sample (2742) Garki District, Kano State, Nigeria, and in (ii) the 534 infants born into the population during five years. Eleven (2.1%) newborn had Hb.SS, as was expected from gene frequency (0.146). Prevalence was maintained in the first year of life, but fell to 0.4% at one to four years and to 0.05% (one person) over the age of nine years. Antimalarial intervention for two transmission seasons was followed by an apparent but not significant decrease in Hb.SS mortality. There was one male aged about 40 years who had Hb.SC (the expected number was three). Hb.SS children were compared to normal subjects at the same age, the same village and the same survey; they had significantly less than the expected Plasmodium malariae infection (P less than 0.01) and lower than median P. falciparum densities while below five years (P less than 0.05). Over one year of age, they tended to have below average indirect fluorescent antibody (IFA) (P less than 0.01), indirect haemagglutinating antibody (IHA) (P less than 0.01) titres and number of precipitin rings (not significant) against P. falciparum antigen, and IFA against P malariae (P less than 0.01). They had above average IgM (P less than 0.05), but their IgG concentrations did not differ from normal. We conclude that (i) sickling is sufficient to protect against P. malariae in Hb.SS but not Hb.AS; (ii) sickling prevents intense P. falciparum infection in Hb.SS, as in Hb.AS; (iii) in Hb.SS, there is less antigenic stimulus and hence less antibody against P. falciparum (like Hb.AS) and P. malariae (unlike Hb.AS); (iv) although less intense, malaria is frequently fatal in Hb.SS, especially in age-group one to four years (unlike Hb.AS); (v) IgM levels are high in Hb.SS in response to frequent infections other than malaria (unlike Hb.AS).

Adolescent↗
PubMed2026

The Source-Sink Dynamics of Plasmodium vivax May Undermine Malaria Elimination Efforts in the Amazon: An Epidemiological and Population Genomic Study.

BACKGROUND: Brazil's progress toward malaria elimination has stalled and 163 000 new cases (more than 80% caused by Plasmodium vivax) were recorded in the Brazilian Amazon in 2023. We hypothesize that human mobility continues to disperse parasites from hotspots to areas with decreasing endemicity. METHODS: We analyzed 5.5 million malaria case notifications between 2003 and 2023 to describe malaria case mobility and identify sources and sinks of P. vivax in the Brazilian Amazon. We leveraged whole-genome sequence data from 408 P. vivax isolates sampled from across South America to characterize parasite gene flow and infer likely regional routes of parasite dispersal. RESULTS: We found that nearly one-third of the P. vivax infections diagnosed in residents in the Brazilian Amazon over 21 years were acquired outside the locality or municipality of residence, but only 1.7% were imported from other countries in South America, mostly from the Guiana Shield. We show that large cities with residual malaria transmission-such as Manaus and Porto Velho-are receptive parasite sinks surrounded by high-risk source rural localities. Although the genetic relatedness of parasites tended to decrease with geographic distance, parasites from sites more than 1000 km apart often remained genetically connected. CONCLUSIONS: Understanding parasite source-sink dynamics on different geographic scales is crucial to target high-risk mobile populations and source localities along with receptive sinks within low-transmission municipalities, with the goal of eliminating malaria transmission and preventing its reintroduction into malaria-free areas.

Humans↗