Clinical impact of vivax malaria: A collection review.

<h4>Background</h4>Plasmodium vivax infects an estimated 7 million people every year. Previously, vivax malaria was perceived as a benign condition, particularly when compared to falciparum malaria. Reports of the severe clinical impacts of vivax malaria have been increasing over the las...

Full description

Bibliographic Details
Main Authors: Aung Pyae Phyo, Prabin Dahal, Mayfong Mayxay, Elizabeth A Ashley
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2022-01-01
Series:PLoS Medicine
Online Access:https://doi.org/10.1371/journal.pmed.1003890
_version_ 1818285085233774592
author Aung Pyae Phyo
Prabin Dahal
Mayfong Mayxay
Elizabeth A Ashley
author_facet Aung Pyae Phyo
Prabin Dahal
Mayfong Mayxay
Elizabeth A Ashley
author_sort Aung Pyae Phyo
collection DOAJ
description <h4>Background</h4>Plasmodium vivax infects an estimated 7 million people every year. Previously, vivax malaria was perceived as a benign condition, particularly when compared to falciparum malaria. Reports of the severe clinical impacts of vivax malaria have been increasing over the last decade.<h4>Methods and findings</h4>We describe the main clinical impacts of vivax malaria, incorporating a rapid systematic review of severe disease with meta-analysis of data from studies with clearly defined denominators, stratified by hospitalization status. Severe anemia is a serious consequence of relapsing infections in children in endemic areas, in whom vivax malaria causes increased morbidity and mortality and impaired school performance. P. vivax infection in pregnancy is associated with maternal anemia, prematurity, fetal loss, and low birth weight. More than 11,658 patients with severe vivax malaria have been reported since 1929, with 15,954 manifestations of severe malaria, of which only 7,157 (45%) conformed to the World Health Organization (WHO) diagnostic criteria. Out of 423 articles, 311 (74%) were published since 2010. In a random-effects meta-analysis of 85 studies, 68 of which were in hospitalized patients with vivax malaria, we estimated the proportion of patients with WHO-defined severe disease as 0.7% [95% confidence interval (CI) 0.19% to 2.57%] in all patients with vivax malaria and 7.11% [95% CI 4.30% to 11.55%] in hospitalized patients. We estimated the mortality from vivax malaria as 0.01% [95% CI 0.00% to 0.07%] in all patients and 0.56% [95% CI 0.35% to 0.92%] in hospital settings. WHO-defined cerebral, respiratory, and renal severe complications were generally estimated to occur in fewer than 0.5% patients in all included studies. Limitations of this review include the observational nature and small size of most of the studies of severe vivax malaria, high heterogeneity of included studies which were predominantly in hospitalized patients (who were therefore more likely to be severely unwell), and high risk of bias including small study effects.<h4>Conclusions</h4>Young children and pregnant women are particularly vulnerable to adverse clinical impacts of vivax malaria, and preventing infections and relapse in this groups is a priority. Substantial evidence of severe presentations of vivax malaria has accrued over the last 10 years, but reporting is inconsistent. There are major knowledge gaps, for example, limited understanding of the underlying pathophysiology and the reason for the heterogenous geographical distribution of reported complications. An adapted case definition of severe vivax malaria would facilitate surveillance and future research to better understand this condition.
first_indexed 2024-12-13T01:03:05Z
format Article
id doaj.art-707565dcec10434d8d2cd32612cdc954
institution Directory Open Access Journal
issn 1549-1277
1549-1676
language English
last_indexed 2024-12-13T01:03:05Z
publishDate 2022-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS Medicine
spelling doaj.art-707565dcec10434d8d2cd32612cdc9542022-12-22T00:04:39ZengPublic Library of Science (PLoS)PLoS Medicine1549-12771549-16762022-01-01191e100389010.1371/journal.pmed.1003890Clinical impact of vivax malaria: A collection review.Aung Pyae PhyoPrabin DahalMayfong MayxayElizabeth A Ashley<h4>Background</h4>Plasmodium vivax infects an estimated 7 million people every year. Previously, vivax malaria was perceived as a benign condition, particularly when compared to falciparum malaria. Reports of the severe clinical impacts of vivax malaria have been increasing over the last decade.<h4>Methods and findings</h4>We describe the main clinical impacts of vivax malaria, incorporating a rapid systematic review of severe disease with meta-analysis of data from studies with clearly defined denominators, stratified by hospitalization status. Severe anemia is a serious consequence of relapsing infections in children in endemic areas, in whom vivax malaria causes increased morbidity and mortality and impaired school performance. P. vivax infection in pregnancy is associated with maternal anemia, prematurity, fetal loss, and low birth weight. More than 11,658 patients with severe vivax malaria have been reported since 1929, with 15,954 manifestations of severe malaria, of which only 7,157 (45%) conformed to the World Health Organization (WHO) diagnostic criteria. Out of 423 articles, 311 (74%) were published since 2010. In a random-effects meta-analysis of 85 studies, 68 of which were in hospitalized patients with vivax malaria, we estimated the proportion of patients with WHO-defined severe disease as 0.7% [95% confidence interval (CI) 0.19% to 2.57%] in all patients with vivax malaria and 7.11% [95% CI 4.30% to 11.55%] in hospitalized patients. We estimated the mortality from vivax malaria as 0.01% [95% CI 0.00% to 0.07%] in all patients and 0.56% [95% CI 0.35% to 0.92%] in hospital settings. WHO-defined cerebral, respiratory, and renal severe complications were generally estimated to occur in fewer than 0.5% patients in all included studies. Limitations of this review include the observational nature and small size of most of the studies of severe vivax malaria, high heterogeneity of included studies which were predominantly in hospitalized patients (who were therefore more likely to be severely unwell), and high risk of bias including small study effects.<h4>Conclusions</h4>Young children and pregnant women are particularly vulnerable to adverse clinical impacts of vivax malaria, and preventing infections and relapse in this groups is a priority. Substantial evidence of severe presentations of vivax malaria has accrued over the last 10 years, but reporting is inconsistent. There are major knowledge gaps, for example, limited understanding of the underlying pathophysiology and the reason for the heterogenous geographical distribution of reported complications. An adapted case definition of severe vivax malaria would facilitate surveillance and future research to better understand this condition.https://doi.org/10.1371/journal.pmed.1003890
spellingShingle Aung Pyae Phyo
Prabin Dahal
Mayfong Mayxay
Elizabeth A Ashley
Clinical impact of vivax malaria: A collection review.
PLoS Medicine
title Clinical impact of vivax malaria: A collection review.
title_full Clinical impact of vivax malaria: A collection review.
title_fullStr Clinical impact of vivax malaria: A collection review.
title_full_unstemmed Clinical impact of vivax malaria: A collection review.
title_short Clinical impact of vivax malaria: A collection review.
title_sort clinical impact of vivax malaria a collection review
url https://doi.org/10.1371/journal.pmed.1003890
work_keys_str_mv AT aungpyaephyo clinicalimpactofvivaxmalariaacollectionreview
AT prabindahal clinicalimpactofvivaxmalariaacollectionreview
AT mayfongmayxay clinicalimpactofvivaxmalariaacollectionreview
AT elizabethaashley clinicalimpactofvivaxmalariaacollectionreview