Malaria Control & Elimination

The antimalarial activity of some bisbenzylisoquinoline (BBIQ) alkaloids were studied using in vitro culture of both chloroquine (CQ)-sensitive and chloroquine-resistant strains of Plasmodium falciparum. The combination of chloroquine and tetrandrine gave a 44 fold potentiation of malarial killing. Fangchinoline, hernandezine, pycnamine, berbamine and isotetrandrine had similar antimalarial activity as tetrandrine against the sensitive strain of P. falciparum malaria. Hernandezine, isotetrandrine, berbamine, fangchinoline and methoxyadiantifoline had similar antimalarial activity as tetrandrine against a strain of chloroquine-resistant falciparum malaria. Based on structure/ activity analysis, we concluded that the stereochemistry of C-1ʹ (S ring) of the BBIQ structure played an important role in selective action against resistant malaria. The stereochemistry of C-1 (left ring) and a substituent of C-12 appeared to have little influence on the selectivity. The point of attachment of the ether bridges to the rings also exerts an important influence on selective antimalarial activity. Tetrandrine (TT) penetrates both the erythrocyte and parasite membranes and inhibits the synthesis and activity of the (MDR) pump and likely the Plasmodium falciparum chloroquine resistance transporter (Pfcrt) since it inhibits the calcium channel. These observations likely account for the fact TT potentiates the activity of chloroquine more than 40 fold against chloroquine resistant falciparum malaria.

Accurate malaria diagnosis is necessary to prevent unnecessary deaths and curb malaria drug resistance related to unnecessary treatment. While numerous diagnostic assays exist, the need for a low-cost, rapid and highly accurate malaria test remains. Here we evaluate the diagnostic performance of a computer vision platform, the Sight Diagnostic P2 device for malaria diagnosis, speciation and parasite quantification. The trial was conducted at two centers on Plasmodium falciparum and Plasmodium vivax samples, using different testing protocols: 374 samples were collected at City Hospital Mangalore India and 167 samples were collected at Lancet Laboratories Johannesburg South Africa. At City Hospital, the device diagnoses were compared to RT-PCR results while at Lancet Laboratories the device diagnoses were compared to a panel of tests provided by the clinic. For identification of malaria, the device demonstrated a sensitivity of 97% and a specificity of 99.5% at City Hospital India, and a sensitivity of 97.8% and a specificity of 97.5% at Lancet Laboratories Johannesburg. For speciation, the device correctly identified 87.5% for Plasmodium Vivax and 93.5% for Plasmodium Falciparum at City Hospital India. Lastly, comparing the device parasite count with that of trained microscopes, produced an average pearsons correlation of 0.87.

In the past decade there has been a significant reduction in malaria incidence globally. In some places continuous surveillance has indicated that the reduction in malaria cases has been sustained to the point of near elimination. The drastic reduction in malaria cases may be attributed to the unprecedented financial support to national malaria control programmes by several donors. The use of interventions such as insecticide treated nets, indoor residual insecticide spraying and to some extent environmental manipulation aimed at eliminating mosquito breeding sites have been responsible for the gains achieved. Application of a combination of these measures has brought about heterogeneity of malaria transmission within some countries. Some areas have recorded drastic reduction in the malaria burden, whereas in other parts of the same country transmission has remained relatively unchanged. This situation implicitly indicates that different approaches to malaria prevention and control or elimination are required in different parts of the same country. Changing malaria epidemiological patterns should also dictate the methods of malaria surveillance that are not only robust but also cost effective. Techniques for malaria diagnosis to support surveillance have to be sensitive and specific enough to pick up the lingering infections especially in low malaria transmission areas. In many malaria endemic countries application of such methods also require deployment of resources differentially in various parts of the same country, and that is a challenge. Chemoprophylaxis has been used in various ways to prevent malaria or avoid its complications in vulnerable populations. When transmission becomes low, new criteria are needed to identify populations that become more vulnerable to the adverse effects of malaria and qualify for chemoprophylaxis. The dynamic malaria epidemiological patterns emerging within countries are presenting unprecedented challenges that will need novel and cost effective ways of managing resources to sustain the reduction or elimination of malaria.

Background Malaria, pneumonia and diarrhea remains to be the major causes of morbidity and mortality among children in Uganda. To address such challenges, the government adopted a national policy on Integrated Community Case Management (ICCM) for malaria, pneumonia and diarrhea in 2010. The aim of this study was to assess household access, utilization and acceptability of ICCM services in Kabarole District. Methods A cross sectional household survey was conducted amongst caretakers of children below 5 years of age and a total of 384 respondents were interviewed about distance from nearest health facility and community health worker, socio-demographic characteristics, type of housing, history of fever, health-seeking behavior, perceptions of quality and utilization of ICCM services. Data was cleaned, coded and analysed using STATA 14.0 to produce results. Results Most 53.1% of the studied children were males and their age ranged from 1-52 months. Nearly all the care takers, 97.1% (373/384) had utilized health services for their children in the three proceeding months to the study and only 27.3% (102/373) had utilized ICCM services. Trust in CHWs (AOR 0.85, 95%CI [0.641-1.135]), level of awareness (AOR 0.73, 95%CI [0.538-0.979]) and distance (≤1km) to CHWs (AOR 1.65, 95%CI [1.075-2.522]) are positively associated with the utilisation of ICCM services. Conclusion The implementation of ICCM policy in kabarole has been an effective approach in increasing the utilization of malaria, diarrhea and pneumonia treatment services and hence increasing access to health services at community level. Trust in the CHWs, level of community awareness and distance to the CHWs are positively associated with the utilisation of ICCM services