Severe vivax malaria trends in the last two years: a study from a tertiary care centre, Delhi, India.

BACKGROUND: Plasmodium vivax, once considered benign species, is recently being recognised to be causing severe malaria like Plasmodium falciparum. In the present study, the authors report the trends in malaria severity in P. vivax among patients from a Delhi government hospital. The aim of the study was to understand the disease severity and the burden of severe vivax malaria. METHODS: A hospital based study was carried out from June 2017 to December 2018 at a tertiary care centre from Delhi, India. Patients were tested for malaria using peripheral blood smear (PBS) and/or rapid malaria antigen test (RMAT). The severe and non-severe vivax malaria categorization was done as per the WHO guidelines. Sociodemographic, clinic and paraclinical data were collected from patients and their medical records. RESULTS: Of the 205 patients, 177 (86.3%) had P. vivax infection, 22 (10.7%) had P. falciparum infection and six (2.9%) had mixed infection with both the species. Out of 177 P. vivax cases included in this study one or more manifestations of severe malaria was found in 58 cases (32.7%). Severe anaemia (56.9%), jaundice (15%) and significant bleeding (15%) were the most common complications reported in most of patients, along with thrombocytopenia. CONCLUSIONS: In this study, it is evident that vivax malaria is emerging as the new severe disease in malaria patients, a significant shift in the paradigm of P. vivax pathogenesis. The spectrum of complications and alterations in the laboratory parameters in P. vivax clinical cases also indicate the recent shift in the disease severity.

Prevalence of Plasmodium falciparum field isolates with deletions in histidine-rich protein 2 and 3 genes in context with sub-Saharan Africa and India: a systematic review and meta-analysis.

BACKGROUND: In 2017, nearly 80% of malaria morbidity and mortality occurred in sub-Saharan African (SSA) countries and India. Rapid diagnostic tests (RDTs), especially those targeting histidine-rich protein 2 (PfHRP2) of Plasmodium falciparum, have become an important diagnostic tool in these malaria-endemic areas. However, the chances of RDT-oriented successful treatment are increasingly jeopardized by the appearance of mutants with deletions in pfhrp2 and pfhrp3 genes. This systematic review and meta-analysis determines the prevalence of field P. falciparum isolates with deletion in pfhrp2 and/or pfhrp3 genes and their proportion among false-negative results in the PfHRP2-based RDTs in SSA and India. METHODS: Eight electronic databases were used for searching potentially relevant publications for the systematic review analysis, wherein the main methodological aspects of included studies were analysed and some missing links in the included studies were identified. RESULTS: A total of 19 studies were included, 16 from SSA and 3 from India. The pooled prevalence of pfhrp2 deletions was 8 and 5% while 16 and 4% for pfhrp3 gene deletions in Africa and India, respectively. The pooled proportion of pfhrp2 gene deletions found among false negative PfHRP2-based RDTs results was about 27.0 and 69.0% in Africa and India, respectively. CONCLUSIONS: This review study indicates a relatively high proportion of both pfhrp2/3 genes deletions in P. falciparum isolates and among false-negative malaria cases using PfHRP2-based RDT results in SSA and India. Recently the deletions in pfhrp2/3 genes have also been reported from two African countries (Nigeria and Sudan). This review emphasizes the importance of more extensive studies and standardization of studies addressing the pfhrp2/3 gene deletions in malarious areas.