Diagnostic performance of rapid diagnostic test, light microscopy and polymerase chain reaction during mass survey conducted in low and high malaria-endemic areas from two North-Eastern states of India.

An early and accurate diagnosis followed by prompt treatment is pre-requisite for the management of any disease. Malaria diagnosis is routinely performed by microscopy and rapid diagnostic tests (RDTs) in the field settings; however, their performance may vary across regions, age and asymptomatic status. Owing to this, we assessed the diagnostic performance of conventional and advanced molecular tools for malaria detection in low and high malaria-endemic settings. We performed mass blood surveys in low and high endemic regions of two North-Eastern districts from the states of Assam and Meghalaya. A total of 3322 individuals were screened for malaria using RDT, microscopy and PCR and measures of diagnostic accuracy were estimated. Out of 3322 individuals, 649 (19.5%) were detected with malaria parasite. Asymptomatic were 86.4% (2872/3322), of which 19.4% (557/2872) had Plasmodium infection. The sensitivity and specificity of microscopy were 42.7% and 99.3%, and RDT showed 49.9% and 90.4%, respectively, considering PCR as standard. RDT (AUC: 0.65 vs 0.74; p = 0.001) and microscopy (AUC: 0.64 vs 0.76; p < 0.0001) performances were significantly lower in low compared to high endemic areas. True positive rate was lower in asymptomatics but true negative rate was found similar to symptomatic individuals. The conventional diagnostic tools (RDT and microscopy) had detected malaria in children with nearly twofold greater sensitivity than in the adults (p < 0.05). To conclude, asymptomatics, adults and low malaria-endemic regions require major attention due to mediocre performance of conventional diagnostic tools in malaria detection.

Unlicensed medical practitioners in tribal dominated rural areas of central India: bottleneck in malaria elimination.

BACKGROUND: In India, Accredited Social Health Activists (ASHAs) deliver services for diagnosis and treatment of malaria, although unlicensed medical practitioners (UMPs) (informal health providers) are most preferred in communities. A cross sectional survey was conducted to: (i) assess knowledge and treatment-seeking practices in the community, and (ii) explore the diagnosis and treatment practices related to malaria of UMPs working in rural and tribal-dominated high malaria endemic areas of central India, and whether they adhere to the national guidelines. METHODS: A multi-stage sampling method and survey technique was adopted. Heads of the households and UMPs were interviewed using a structured interview schedule to assess knowledge and malaria treatment practices. RESULTS: Knowledge regarding malaria symptoms was generally accurate, but misconceptions emerged related to malaria transmission and mosquito breeding places. Modern preventive measures were poorly accessed by the households. UMPs were the most preferred health providers (49%) and the first choice in households for seeking treatment. UMPs typically lacked knowledge of the names of malaria parasite species and species-specific diagnosis and treatment. Further, irrational use of anti-malarial drugs was common. CONCLUSIONS: UMPs were the most preferred type of health care providers in rural communities where health infrastructure is poor. The study suggests enhancing training of UMPs on national guidelines for malaria diagnosis and treatment to strengthen their ability to contribute to achievement of India's malaria elimination goals.

Socioeconomic determinants of community knowledge and practice in relation to malaria in high- and low-transmission areas of central India.

This study was undertaken with an aim of exploring community knowledge and treatment practices related to malaria and their determinants in high- and low-transmission areas of central India. A community-based cross-sectional study was carried out between August 2015 and January 2016 in two high- and two low-malaria-endemic districts of central India. A total of 1470 respondents were interviewed using a pre-tested structured interview schedule. Respondents residing in high-transmission areas with higher literacy levels, and of higher socioeconomic status, were found to practise more modern preventive measures than those living in low-transmission areas with low literacy levels and who were economically poor. Level of literacy, socioeconomic status and area (district) of residence were found to be the main factors affecting people's knowledge of malaria aetiology and clinical features, and prevention and treatment practices, in this community in central India.

Association of dietary intake below recommendations and micronutrient deficiencies during pregnancy and low birthweight.

Background Pregnancy is associated with biochemical changes leading to increased nutritional demands for the developing fetus that result in altered micronutrient status. The Indian dietary pattern is highly diversified and the data about dietary intake patterns, blood micronutrient profiles and their relation to low birthweight (LBW) is scarce. Methods Healthy pregnant women (HPW) were enrolled and followed-up to their assess dietary intake of nutrients, micronutrient profiles and birthweight using a dietary recall method, serum analysis and infant weight measurements, respectively. Results At enrolment, more than 90% of HPW had a dietary intake below the recommended dietary allowance (RDA). A significant change in the dietary intake pattern of energy, protein, fat, vitamin A and vitamin C (P < 0.001) was seen except for iron (Fe) [chi-squared (χ2) = 3.16, P = 0.177]. Zinc (Zn) deficiency, magnesium deficiency (MgDef) and anemia ranged between 54-67%, 18-43% and 33-93% which was aggravated at each follow-up visit (P ≤ 0.05). MgDef was significantly associated with LBW [odds ratio (OR): 4.21; P = 0.01] and the risk exacerbate with the persistence of deficiency along with gestation (OR: 7.34; P = 0.04). Pre-delivery (OR: 0.57; P = 0.04) and postpartum (OR: 0.37; P = 0.05) anemia, and a vitamin A-deficient diet (OR: 3.78; P = 0.04) were significantly associated with LBW. LBW risk was much higher in women consuming a vitamin A-deficient diet throughout gestation compared to vitamin A-sufficient dietary intake (OR: 10.00; P = 0.05). Conclusion The studied population had a dietary intake well below the RDA. MgDef, anemia and a vitamin A-deficient diet were found to be associated with an increased likelihood of LBW. Nutrient enrichment strategies should be used to combat prevalent micronutrient deficiencies and LBW.

Epidemiology of malaria and anemia in high and low malaria-endemic North-Eastern districts of India.

Anemia and malaria are the two major public health problems that lead to substantial morbidity and mortality. Malaria infection destroys erythrocytes, resulting in low hemoglobin (Hb) levels known as anemia. Here we report the determinants of anemia in high and low malaria-endemic areas that would help understand which parasite densities, age, and gender-associated low Hb levels. Therefore, a cross-sectional mass survey (n = 8,233) was conducted to screen anemia and malaria in high and low malaria-endemic districts (HMED and LMED) of North-East India. Axillary body temperature was measured using a digital thermometer. The prevalence of anemia was found to be 55.3% (4,547/8,233), of which 45.1% had mild (2,049/4,547), 52.1% moderate (2,367/4,547) and 2.9% had severe anemia (131/4,547). Among anemic, 70.8% (3,219/4,547) resided in LMED and the rest in HMED. The median age of the anemic population was 12 years (IQR: 7-30). Overall, malaria positivity was 8.9% (734/8,233), of which HMED shared 79.6% (584/734) and LMED 20.4% (150/734) malaria burden. The village-wise malaria frequency was concordant to asymptomatic malaria (10-20%), which showed that apparently all of the malaria cases were asymptomatic in HMED. LMED population had significantly lower Hb than HMED [standardized beta (ß) = -0.067, p < 0.0001] and low-density Plasmodium infections had higher Hb levels than high-density infections (ß = 0.113; p = 0.031). Women of reproductive age had higher odds for malaria (OR: 1.42; 95% CI: 1.00-2.05; p = 0.04). Females (ß = -0.193; p < 0.0001) and febrile individuals (ß = -0.029; p = 0.008) have shown lower Hb levels, but malaria positivity did not show any effect on Hb. Young children and women of reproductive age are prone to anemia and malaria. Although there was no relation between malaria with the occurrence of anemia, we found low-density Plasmodium infections, female gender, and LMED were potential determinants of Hb.

Unreported mixed Plasmodium species infection may increase vivax malaria in India: a challenge for malaria elimination.

BACKGROUND: In India, there are several malaria-endemic regions where non-falciparum species coexist with Plasmodium falciparum. Traditionally, microscopy and rapid diagnostic tests are used for the diagnosis of malaria. Nevertheless, microscopy often misses the secondary malaria parasite in mixed-infection cases due to various constraints. Misdiagnosis/misinterpretation of Plasmodium species leads to improper treatment, as the treatment for P. falciparum and Plasmodium vivax species is different, as per the national vector-borne disease control program in India. METHODS: Blood samples were collected from malaria-endemic regions (Jharkhand, Madhya Pradesh, Chhattisgarh, Maharashtra, Odisha, Assam, Meghalaya, Mizoram and Telangana) of India covering almost the entire country. Molecular diagnosis of Plasmodium species was carried out among microscopically confirmed P. falciparum samples collected during a therapeutic efficacy study in different years. RESULTS: The polymerase chain reaction analysis revealed a high prevalence (18%) of mixed malaria parasite infections among microscopically confirmed P. falciparum samples from malaria patients that are either missed or left out by microscopy. CONCLUSIONS: Deployment of molecular tools in areas of mixed species infection may prove vital for accurate diagnosis and treatment of malaria. Further, it will help in achieving the goal of malaria elimination in India.

Asymptomatic low-density Plasmodium infection during non-transmission season: a community-based cross-sectional study in two districts of North Eastern Region, India.

BACKGROUND: Malaria elimination requires targeting asymptomatic and low-density Plasmodium infections that largely remain undetected. Therefore we conducted a cross-sectional study to estimate the burden of asymptomatic and low-density Plasmodium infection using conventional and molecular diagnostics. METHODS: A total of 9118 participants, irrespective of age and sex, were screened for malaria using rapid diagnostic tests (RDTs), microscopy and polymerase chain reaction. RESULTS: Among the participants, 707 presented with symptoms and 8411 without symptoms, of which Plasmodium was present in 15.6% (110/707) and 8.1% (681/8411), respectively. Low-density infection was found in 5.1% (145/2818) of participants and 8327 of 9118 were Plasmodium negative. Endemicity was propotional to asymptomatic infections (high endemicity 11.1% [404/3633] vs low endemicity 5.8% [277/4778]; odds ratio [OR] 2.0 [95% confidence interval {CI} 1.7 to 2.4]) but inversely related to low-density infection (high endemicity 3.7% [57/1545] vs low endemicity 6.9% [88/1273]; OR 1.9 [95% CI 1.4 to 2.7]). The spleen rate in children 2-9 y of age was 17.9% (602/3368) and the enlarged spleen index was 1.6. Children between 8 and 14 y showed higher odds for asymptomatic (adjusted OR [aOR] 1.75 [95% CI 1.4 to 2.2]) and low-density infections (aOR 0.63 [95% CI 0.4 to 1.0)] than adults. CONCLUSIONS: The prevalence of asymptomatic and low-density Plasmodium infection undermines the usefulness of standard diagnostic tools used by health agencies. This necessitates deploying molecular tools in areas where malaria microscopy/RDTs indicate a dearth of infection.

Novel molecular diagnostic technique for detecting the different species of Plasmodium.

BACKGROUND: Sensitive diagnostic techniques are needed for timely detection of malaria parasite and disease control. Molecular diagnostic techniques involving Polymerase chain reaction (PCR) with 18 s rRNA as a known diagnostic target with an overall sensitivity of 10 parasites per microliter is used as a gold standard. Till date, no attempt has been undertaken to develop a technique for the identification of four Plasmodium species in a single step PCR combined with restriction digestion with enzymes. METHOD: Plasmodium species-specific polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays have been developed, based on RFLP of amplified PCR product of mitochondrial gene as a target. This approach identifies Plasmodium species in two steps involving amplification of mitochondrial (Mt) gene by PCR followed by digestion with restriction enzymes. RESULT: A total of 36 clinical samples were subjected to PCR-RFLP for the diagnosis and detection of malaria parasites targeting mitochondrial gene (Mt). The findings of the method were compared with gold standard methods (Microscopy, RDTs and Nested PCR) and was able to detect mixed infection with a sensitivity of 100% and specificity of 93.8% with respect to nested PCR. The results obtained by PCR-RFLP were validated with Sanger sequencing (n = 32) and were found to be consistent with the method. CONCLUSION: This method identifies and distinguishes four species of human malaria parasite namely P. falciparum (Pf), P. vivax (Pv), P. malariae (Pm) and P. ovale (Po) in approximately 4 h. To overcome and address PCR difficulties, continuous efforts are needed for the development of newer diagnostic techniques.

The economic cost of malaria at the household level in high and low transmission areas of central India.

The cost burden of malaria at the household level, resulting from complex social, economic, and epidemiological factors, is enormous. This study was carried out to estimate the economic burden of malaria at the household level in low and high malaria transmission areas of central India. We conducted surveys with households in which at least one member had suffered from malaria in the three months preceding the survey. The human capital method was used to estimate the cost of malaria at the household level. We found that the total cost per episode of malaria was higher in high transmission areas than low transmission areas; direct costs were generally higher for adults than for children. Males spent more on diagnosis and treatment than females, and the mean work absenteeism due to malaria was higher among male adult patients than among females, though work time lost due to child illness was lower for male caregivers. Households belonging to high and middle socioeconomic status (SES) spent significantly more on malaria illness than those of low SES. However, the economic burden of malaria relative to annual incomes was highest among low SES households. Populations belonging to high transmission areas were more vulnerable to malarial infection due to geo-climatic, demographic, socioeconomic, and cultural factors, as well as the relatively poor access to health facilities that characterize these regions. Additionally, poor health-seeking practices not only increase the cost burden but also adversely affect patients' health and productivity, which lead to opportunity losses while imposing a greater economic burden on households.

The changing dynamics of Plasmodium vivax and P. falciparum in central India: trends over a 27-year period (1975--2002).

The changing epidemiology of malaria since 1975 was studied in a tribal forested belt of central India, Chhattisgarh state, which is the second most highly malarious state in India. Chhattisgarh, which accounts for 2% of the total population of the country, contributed >16% of the total malaria cases, 23% of Plasmodium falciparum, and 7% of deaths due to malaria in the country. Retrospective analysis further revealed that, in 1975--76, P. vivax was the predominant species (58%); however, since 1979, P. falciparum showed a steady upward trend (50%), and in 2002. P. vivax reduced to 28%. Between 1986 and 2000, P. falciparum cases reported by the National Anti Malaria Programme have increased 500%, and the number of deaths also showed a similar alarming increase. From 2000 to 2002, though the number of malaria infections and number of deaths declined sharply as a result of intensive intervention measures (30% and 95%, respectively), which included new drugs like Sulfadoxine Pyrimethamine and Arteether under Enhanced Malaria Control Programme, the proportion of P. falciparum has held steady without any decline. Moreover, along with Anopheles fluviatilis, the traditional vector in the forest, An. culicifacies has also established itself in the forest. The comeback of malaria and establishment of new vectors was largely due to the deterioration of health services along with emergence of resistance in P. falciparum to Chloroquine and in An. culicifacies to DDT. Therefore, a more diversified malaria control program might be needed for sustainable malaria control.