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Malaria remains a major public health challenge worldwide. In order to ensure a prompt and accurate malaria diagnosis, the World Health Organization recommended the confirmatory parasitological diagnosis of malaria by microscopy and malaria rapid diagnostic test (RDT) prior to antimalarial administration and treatment. This study was designed to evaluate the performance of nested polymerase chain reaction (nested PCR), light microscopy, and Plasmodium falciparum histidine-rich protein 2 rapid diagnostic test (PfHRP2 RDT) in the detection of falciparum malaria in Akure, Nigeria. A cross-sectional and hospital-based study involving 601 febrile volunteer participants was conducted in Akure, Nigeria. Approximately 2-3 mL venous blood samples were obtained from each study participant for parasitological confirmation by microscopy and PfHRP2-based malaria RDT. Thick and thin films were prepared and viewed under the light microscope for parasite detection, parasite density quantification, and species identification, respectively. Dry blood spot samples were prepared on 3MM Whatman filter paper for nested PCR. The overall prevalence of microscopy, PfHRP2 RDT, and nested PCR were 64.89% (390/601), 65.7% (395/601), and 67.39% (405/601), respectively. The estimates of sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and Youden's j index of microscopy and RDT were 96.30, 100.00, 100.00, 92.89, 97.50, 0.963, and 95.06, 94.90, 97.47, 90.29, 95.01, and 0.899, respectively. Malaria RDT recorded higher false negativity, compared microscopy (4.94% vs. 3.70%). A near perfect agreement was reported between microscopy and nested PCR, and between PfHRP2 RDT and nested PCR with Cohen's kappa (k) values of 0.94 and 0.88, respectively. This study revealed that PfHRP2 RDT and microscopy continues to remain sensitive and specific for falciparum malaria diagnosis in the study area.
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BACKGROUND: Malaria remains a serious public health problem worldwide, particularly in tropical and subtropical regions, including Nigeria. This study investigates the prevalence, parasite density and determinants of malaria among symptomatic children in some peri-urban communities in southwestern Nigeria. METHODS: This was a randomized cross-sectional and hospital-based study. The standard method of microscopy was employed. Thick and thin films were prepared and viewed under a light microscope to identify and quantify malaria parasites. A well-structured and pre-tested questionnaire was used to obtain the subject's information on the demographic, socio-economic and environmental variables. RESULTS: A total of 380 (71.7%) participants were infected with Plasmodium falciparum with a mean parasite density of 1857.11 parasite/µL of blood. Malaria prevalence and mean parasite density were significantly higher among male compared to their female counterparts [80.3% vs 61.4% and 2026.46 vs 1619.63 parasite/µL of blood]. Similarly, age group ≤5 years had the highest malaria prevalence (92.2%) and mean parasite density (2031.66 parasite/µL of blood) than other age groups (AOR 2.281, 95% CI: 1.187-4.384, P < 0.05). The multivariate logistic analysis showed that malaria disease is significantly associated with having mother with no formal education (AOR 12.235, 95% CI: 3.253-46.021, P < 0.05), having well and river as a major source of household water supply (AOR 13.810, 95% CI: 3.012-63.314, P < 0.05 vs AOR 5.639, 95% CI: 1.455-21.853, P < 0.05) and presence of stagnant water around home (AOR 5.22, 95% CI: 2.921-9.332, P < 0.05). Furthermore, protective factors observed include ownership of mosquito bed net (AOR 0.474, 95% CI: 0.223-1.008, P < 0.05) and distance of home to hospital (AOR 0.279, 95% CI: 0.158-0.493, P < 0.05). CONCLUSION: Malaria remains a serious public health problem in the study area. Adopting integrated malaria control measures including educating parents on malaria prevention and control strategies, distributing mosquito bed nets, and establishing larvae source management program is highly imperative.
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BACKGROUND: Malaria is a severe global public health challenge that causes significant morbidity and mortality worldwide, particularly in sub-Saharan Africa. This study was designed to determine the prevalence, parasite density, and risk factors associated with malaria infection transmission among residents of two urban communities of Ibadan, southwestern Nigeria. MATERIALS AND METHODS: A cross-sectional hospital-based study was carried out on 300 participants. Blood samples were obtained. Thick and thin blood films were prepared and viewed using the standard parasitological technique of microscopy. Moreover, data on sociodemographic and environmental variables were obtained using a pre-tested standard questionnaire. RESULTS: Of the 300 participants examined, a total of 165 (55.0%) were found positive for Plasmodium falciparum with a mean (S.D) parasite density of 1814.70 (1829.117) parasite/µL of blood. The prevalence and parasite density of malaria infection vary significantly (P < 0.05) with age group. Children <5 years old were more likely to have malaria infection and high parasite densities than adults (p < 0.05). Similarly, in relation to gender, males significantly (P < 0.05) had a higher prevalence (60.2%) and mean (S.D) parasite density of malaria infection [2157.73 (1659.570) parasite/µL of blood] compared to females. Additionally, those without formal education had the highest prevalence (73.0%) and mean (S.D) parasite density of infection [2626.96 (2442.195) parasite/µL of blood]. The bivariate logistic regression analysis shows that age group 6-10 (Crude Odds Ratio, COR 0.066, 95% CI: 0.007-0.635), presence of streams/rivers (COR 0.225, 95% CI: 0.103-0.492), distance from streams/rivers within ≤1 km (COR 0.283, 95% CI: 0.122-0.654) and travel to rural area (COR 4.689, 95% CI: 2.430-9.049) were the significant risk factors. CONCLUSIONS: Malaria infection is prevalent in the study area and was greatly influenced by traveling activities from the rural areas to urban centers and vice versa. Multifaceted and integrated control strategy should be adopted. Health education on mosquito prevention and chemoprophylaxis before and during travel to rural areas are essential.
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Blastocystis is the most frequently observed eukaryotic gastrointestinal symbiont in humans and animals. Its low host specificity and zoonotic potential suggest that animals might serve as possible reservoirs for transmission. The prevalence and subtype distributions of Blastocystis sp. in animal populations in Southeast Asia, a hotspot for zoonotic diseases, are reviewed. Recommendations for future research aimed at understanding the zoonotic role of Blastocystis are also included. Seven countries have, so far, reported Blastocystis infection in various animals, such as livestock, poultry, companion animals, and non-human primates. Pigs were the most studied animals, and there were records of 100% prevalence in pigs, cattle, and ostriches. Using polymerase chain reaction (PCR)-based approaches, twelve Blastocystis sp. subtypes (STs), namely ST1, ST2, ST3, ST4, ST5, ST6, ST7, ST8, ST9, ST10, ST12, and ST14 have been recognised infecting animals of Southeast Asia. ST1 and ST5 were the most frequently identified, and Malaysia observed the most diverse distribution of subtypes. Further investigations on Blastocystis sp. in various animal hosts, using adequate sample sizes and uniform detection methods, are essential for a better understanding of the distribution of this organism. Detailed genome studies, especially on STs shared by humans and animals, are also recommended.
