Genetic diversity of Plasmodium vivax isolates from pregnant women in the Western Brazilian Amazon: a prospective cohort study
Open accessAbstract
Each year, 92 million pregnant women are at risk of contracting malaria during pregnancy, with the underestimation of the mortality and morbidity burden associated with Plasmodium vivax. During pregnancy, P. vivax infection is associated with low birth weight, maternal anaemia, premature delivery, and stillbirth. In the State of Acre (Brazil), high transmission leaves pregnant women at greater risk of contracting malaria and having a greater number of recurrences. The study of genetic diversity and the association of haplotypes with adverse pregnancy effects is of great importance for the control of the disease. Here we investigate the genetic diversity of P. vivax parasites infecting pregnant women across their pregnancies. P. vivax DNA was extracted from 330 samples from 177 women followed during pregnancy, collected in the State of Acre, Brazil. All samples were negative for Plasmodium falciparum DNA. Sequence data for the Pvmsp1 gene was analysed alongside data from six microsatellite (MS) markers. Allelic frequencies, haplotype frequencies, expected heterozygosity (HE) were calculated. Whole genome sequencing (WGS) was conducted on four samples from pregnant women and phylogenetic analysis performed with other samples from South American regions. Initially, the pregnant women were stratified into two groups—1 recurrence and 2 or more recurrences—in which no differences were observed in clinical gestational outcomes or in placental histological changes between the two groups. Then we evaluated the parasites genetically. An average of 18.5 distinct alleles were found at each of the MS loci, and the HE calculated for each marker indicates a high genetic diversity occurring within the population. There was a high percentage of polyclonal infections (61.7%, 108/175), and one haplotype (H1) occurred frequently (20%), with only 9 of the haplotypes appearing in more than one patient. Most pregnant women had polyclonal infections that could be the result of relapses and/or re-infections. The high percentage of H1 parasites, along with the low frequency of many other haplotypes are suggestive of a clonal expansion. Phylogenetic analysis shows that P. vivax population within pregnant women clustered with other Brazilian samples in the region. FAPESP and CNPq - Brazil.
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
A phylogenetic analysis examining the evolutionary relationships between the organisms shows that the P.vivax population is globally distributed among pregnant women.
“A phylogenetic analysis examining the evolutionary relationships between the organisms shows that the P.vivax population is globally distributed among pregnant women [163–166].”
From Current update on malaria in pregnancy: a systematic review (2025) · cites this paper as [165]
The Results (Genomic diversity of samples with haplotype 1) say the pregnant women’s P. vivax samples clustered with samples from non-pregnant people in Acre, Brazil, while the other samples showed geographical clustering. The Discussion likewise describes clustering with Brazilian samples in the region, not a globally distributed population among pregnant women. (LLM, conf=0.89)
Checked by a reasoning model — may be wrong.
Experimental — accuracy not yet measuredP.falciparum has been linked to specific genotypes associated with asymptomatic infections at the time of delivery.
“Interestingly, P.falciparum has been linked to specific genotypes associated with asymptomatic infections at the time of delivery.”
From Current update on malaria in pregnancy: a systematic review (2025) · cites this paper as [165]
The Introduction (page not provided) reports that P. falciparum genotypes correlate with different disease outcomes and that specific haplotypes have been associated with low birth weight. It does not report an association with asymptomatic infection at delivery; the paper’s own haplotype analysis concerns P. vivax. (LLM, conf=0.82)
Experimental — accuracy not yet measuredThe genetic diversity of P.vivax is remarkable, with the existence of different haplotypes and the ability to develop at lower temperatures, in contrast to the lower genetic diversity observed in P.falciparum.
“In addition, the genetic diversity of P.vivax is remarkable, with the existence of different haplotypes (groups of genetic variations) and the ability to develop at lower temperatures, in contrast to the lower genetic diversity observed in P.falciparum.”
From Current update on malaria in pregnancy: a systematic review (2025) · cites this paper as [165]
The Introduction (page not provided) says P. vivax has higher genetic diversity than P. falciparum, and Results > Haplotype diversity (page not provided) identifies multiple P. vivax haplotypes. The paper does not support the claim that P. vivax can develop at lower temperatures; searches for lower-temperature development found no relevant passage. (LLM, conf=0.88)
Experimental — accuracy not yet measuredPregnant women often have polyclonal infections, which can result from either relapses or reinfections.
“Studies have shown that pregnant women often have polyclonal infections, which can result from either relapses or reinfections.”
From Current update on malaria in pregnancy: a systematic review (2025) · cites this paper as [165]
P.vivax can form dormant stages, known as hypnozoites, in the hepatocytes (liver cells).
“This parasite can form dormant stages, known as hypnozoites, in the hepatocytes (liver cells).”
From Current update on malaria in pregnancy: a systematic review (2025) · cites this paper as [165]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
The citation lists haven’t been fetched yet
References 37 · Cited by 5
- Authors
- Dombrowski, J. G., Acford-Palmer, H., Campos, M., Separovic, E. P. M., Epiphanio, S., Clark, T. G., Campino, S., & Marinho, C. R. F.
- Affiliations
- Universidade de São Paulo (BR)
- London School of Hygiene & Tropical Medicine (GB)
- Corresponding author
- Campino, Susana
- Venue
- The Lancet Regional Health - Americas
- Publisher
- Elsevier BV
- Published
- 2023-02
- Volume
- 18
- Pages
- 100407
- ISSN
- 2667-193X (ISSN-L)
- PMC
- PMC9950542
- OpenAlex
- W4310574855
- Cited by
- 5
- References
- 37
- Citations by year
- 2025: 1 · 2024: 4
- FWCI
- 1.10
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- The Lancet Regional Health - Americas (publishedVersion, cc-by-nc-nd)
- PubMed Central (publishedVersion, cc-by-nc-nd)
- PubMed (publishedVersion)
- LSHTM Research Online (London School of Hygiene and Tropical Medicine) (acceptedVersion)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Funders
- Fundação de Amparo à Pesquisa do Estado de São Paulo (2022/02771-3, 2019/, 20/06747-4, 2019/12068‐5, 18/20468-0, 17/05782-8, 20/03163-1)
- Conselho Nacional de Desenvolvimento Científico e Tecnológico (-0 and, 409216/2018-6, 2019-5, 408636/2018-1, 302917/2019-5, 2017/05782-8, -8 and)
- Medical Research Council (MR/R025576/1, MR/M01360X/1, MR/R020973/1, MR/N010469/1)
- Topics
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Malaria Research and Control
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Genetic diversity and population structure
- Life Sciences › Immunology and Microbiology › Parasitology › Bird parasitology and diseases
- Keywords
- Plasmodium vivax, malaria in pregnancy, genetic diversity, haplotypes, microsatellite markers, polyclonal infection, relapse, reinfection, clonal expansion, placental malaria, Amazon
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
