Plasmodium parasites carried by female Anopheles mosquitoes cause malaria in humans. It is one of the most common vector-borne diseases in India. [1]

The female Anopheles mosquito is the definitive host of the malaria parasite, while humans are considered the intermediate hosts. When an individual is bitten by an Anopheles mosquito carrying the parasite, malaria is transmitted through the injection of sporozoites into the bloodstream. Malaria symptoms typically appear between 10 and 14 days after the bite. Several Plasmodium species are responsible for causing malaria, including Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, Plasmodium malariae and Plasmodium knowlesi. Among these, Plasmodium falciparum and Plasmodium vivax are the most prevalent species detected in India. [2,3]

Malaria continues to be a significant global health challenge and its mitigation and eventual elimination require consistent and focused efforts.[4] Rapid antigen detection tests and blood film examination are widely used approaches that play a significant role in malaria eradication efforts. [5]

While rapid diagnostic tests enhance the speed and accessibility of malaria diagnosis, especially in low-resource settings, they involve trade-offs compared to the precision and detail provided by peripheral blood smear microscopy. RDT technology offers quick, practical and result-oriented malaria screening, which is particularly useful in regions with limited access to health services. [6]

Blood film has been the preferred test for confirming malarial cases for some time. However, it relies on experienced personnel and can sometimes take a significant amount of time to complete. In comparison, rapid diagnostic tests simplify and automate the process, allowing for easy and rapid testing at the patient’s bedside without the need for elaborate laboratory facilities. [7]

The purpose of this study is to show how RDTs supersede traditional microscopy in diagnosing malaria, which has gaps in knowledge and techniques that will advise healthcare providers in a variety of settings. Our main goal is to find out which of the two methods is more effective in diagnosing malaria parasites – RDTs or PBS microscopy. It is aimed at evaluating performance of RDTs along with microscopic examination, in terms of their detection rate, specificity, reliability, against each other in various medical settings.

Conducted at the Parasitology section of the Department of Microbiology, TMU Hospital, this investigation followed a cross-sectional observational study design. Ethical clearance from the Institutional Ethical Committee (IEC) was obtained prior to the commencement of the study.

A total of 147 clinical specimens were tested for malaria. Participants included all age groups, as their blood samples were collected when they visited the hospital with presumed malaria symptoms. After obtaining informed consent, blood was drawn from patients using either the finger prick or venipuncture method and collected in EDTA containers. All samples were sent to the Microbiology Department for analysis.

To prepare the blood smears, technicians followed standard procedures. For the thick smear, they carefully put a drop of blood in the center of a clean glass slide and spread it in a uniform pattern. For the thin smear, a smaller drop was placed at one end of another slide and spread using a second slide held at a 30- to 45-degree angle to create a feathered edge. After allowing the films to air-dry thoroughly, Leishman stain was applied and left for 8 to 10 minutes to ensure optimal staining and also add buffer solution.

Each blood film was examined under a 100X oil immersion objective microscope to screen for malarial parasites. Effective treatment and malaria surveillance depend on timely and accurate diagnosis. According to the World Health Organization, all suspected malarial cases should be tested urgently using either microscopic examination or rapid diagnostic tests before treatment is initiated.

Statistical Analysis: When appropriate the data were submitted to Chi square tests. Data interpretation was done through the use of SPSS software while through Excel 7.0 software, graph production was made easy.

Ethics statement: The institutional ethical committee, TMU/ IEC/ 2024-25/ PG/ 136 approved this study. Before initiating any procedures, all participants were informed about the study and gave their consent for sample collection and processing. Before each person would take part in the study, he or she was provided with information regarding the goals and the structure of the study, the ability to refuse the participation or stop the participation at any time, without the effect on the right for access to other health services. All the collected data was kept in strict confidentiality.

After obtaining IEC approval, the study was conducted in the Parasitology unit of the Microbiology Department at TMU Hospital, located in Moradabad, Uttar Pradesh. Malaria diagnosis was conducted on one hundred fourty seven specimens using thick and thin Leishman-stained blood films, as well as rapid diagnostic tests (RDTs) for antigen detection.

The study reported that 107 cases (72.78%) were confirmed by microscopy, while 113 cases (76.87%) tested positive using rapid diagnostic tests.

Out of the 147 peripheral blood films examined, 113 tested positive for malarial parasites. Among the positive samples, 107 (94.69%) were due to Plasmodium vivax infection, and six were Plasmodium falciparum. Of the 107 patients who tested positive for malaria by rapid diagnostic test, 101 (95.28%) were positive for Plasmodium vivax, whereas six were positive for Plasmodium falciparum.  Subjects aged between 21 and 30 years were the most frequently affected among the cases positively diagnosed by both tests

Table 1: Pathogen found in PBS and RDTs diagnoses

Table 2:  Age distribution of Malaria Infection

The research results were gained from a study was carried out in TMU Hospital, 76.87% of the 147 respondents were found to be positive for malaria based on the RDT, and the infection was identified in 59% of the study subjects using microscopy. Measured the effectiveness of diagnostic techniques for detection of malaria infection patterns, whereby out of 147 positive cases, microscopy identified 107 (72.78%) and RDTs: 113 (76.87%). There is almost the same prevalence recorded by Satyanarayana et al. (2014) in the tribal region of Andhra Pradesh with a prevalence rate of 69.1%.[8] However, the same results were published by Karlekar et al from Maharashtra in 2012 at a rate of 4.28% prevalence. [9]

Our study findings showed that the P.vivax positivity (95.28% by micro and 94.69% by RDT) exceeded that of the P.falciparum among the 113 positive samples. Our results showing more P. vivax cases are similar with the results observed from the study conducted in 2013 by Pawandeep et al. from Orissa 96.77% where P. falciparum was predominantly found with 89.1% prevalence, [10] and In 2000, Singh G., et al mentioned the probability distribution of  Plasmodium vivax (54.76%), Plasmodium falciparum (17.80%) and intermixed infections (27.44%). [11]

Among 10 to 30 years of age, there was a high rate of malaria infection and this may be due to spending more time outdoors. Those between 21 and 30 seemed to face the greatest danger. This implied that the younger people were at higher risk of transmission compared to older people. S.R. Karlekar et al. also found similar findings, with a mean age of 24.8 years. [8] On the contrary, Kochar DK et al found out that children, especially those below the age of five, were highly susceptible to P. vivax infection.

The study found that microscopy (PBS) detected malaria in 72.78% of participants, compared to 76.87% detected by RDT. The results demonstrate that both methods yield comparable outcomes. PBS remains the benchmark diagnostic method. Although PBS screening depends on the expertise of a skilled microscopist and may show variations in sensitivity and specificity compared to newer methods, it is both cost-effective and highly reliable. While RDTs are highly specific, they are more expensive than PBS. Therefore, there is a need for a comprehensive diagnostic test that is highly accurate, reliable and affordable.

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