A longitudinal study of the durability of long-lasting insecticidal nets in Zambia.

BACKGROUND: A key goal of malaria control is to achieve universal access to, and use of, long-lasting insecticidal nets (LLINs) among people at risk for malaria. Quantifying the number of LLINs needed to achieve and maintain universal coverage requires knowing when nets need replacement. Longitudinal studies have observed physical deterioration in LLINs well before the assumed net lifespan of 3 years. The objective of this study was to describe attrition, physical integrity and insecticide persistence of LLINs over time to assist with better quantification of nets needing replacement. METHODS: 999 LLINs distributed in 2011 in two highly endemic provinces in Zambia were randomly selected, and were enrolled at 12 months old. LLINs were followed every 6 months up to 30 months of age. Holes were counted and measured (finger, fist, and head method) and a proportional hole index (pHI) was calculated. Households were surveyed about net care and repair and if applicable, reasons for attrition. Functional survival was defined as nets with a pHI <643 and present for follow-up. At 12 and 24 months of age, 74 LLINs were randomly selected for examination of insecticidal activity and content using bioassay and chemical analysis methods previously described by the World Health Organization (WHO). RESULTS: A total of 999 LLINs were enrolled; 505 deltamethrin-treated polyester nets and 494 permethrin-treated polyethylene nets. With 74 used to examine insecticide activity, 925 were available for full follow-up. At 30 months, 325 (33 %) LLINs remained. Net attrition was primarily due to disposal (29 %). Presence of repairs and use over a reed mat were significantly associated with larger pHIs. By 30 months, only 56 % of remaining nets met criteria for functional survival. A shorter functional survival was associated with having been washed. At 24 months, nets had reduced insecticidal activity (57 % met WHO minimal criteria) and content (5 % met WHO target insecticide content). CONCLUSIONS: The median functional survival time for LLINs observed the study was 2.5-3 years and insecticide activity and content were markedly decreased by 2 years. A better measure of net survival incorporating insecticidal field effectiveness, net physical integrity, and attrition is needed.

Characterizing the insecticide resistance of Anopheles gambiae in Mali.

BACKGROUND: The impact of indoor residual spraying (IRS) and long-lasting insecticide nets (LLINs), key components of the national malaria control strategy of Mali, is threatened by vector insecticide resistance. The objective of this study was to assess the level of insecticide resistance in Anopheles gambiae sensu lato populations from Mali against four classes of insecticide recommended for IRS: organochlorines (OCs), pyrethroids (PYs), carbamates (CAs) and organophosphates (OPs). Characterization of resistance was done in 13 sites across southern Mali and assessed presence and distribution of physiological mechanisms that included target-site modifications: knockdown resistance (kdr) and altered acetycholinesterase (AChE), and/or metabolic mechanisms: elevated esterases, glutathione S-transferases (GSTs), and monooxygenases. METHODS: The World Health Organization (WHO) tube test was used to determine phenotypic resistance of An. gambiae s.l. to: dichlorodiphenyltrichloroethane (DDT) (OC), deltamethrin (PY), lambda-cyhalothrin (PY), bendiocarb (CA), and fenitrothion (OP). Identification of sibling species and presence of the ace-1 (R) and Leu-Phe kdr, resistance-associated mutations, were determined using polymerase chain reaction (PCR) technology. Biochemical assays were conducted to detect increased activity of GSTs, oxidases and esterases. RESULTS: Populations tested showed high levels of resistance to DDT in all 13 sites, as well as increased resistance to deltamethrin and lambda-cyhalothrin in 12 out of 13 sites. Resistance to fenitrothion and bendiocarb was detected in 1 and 4 out of 13 sites, respectively. Anopheles coluzzii, An. gambiae sensu stricto and Anopheles arabiensis were identified with high allelic frequencies of kdr in all sites where each of the species were found (13, 12 and 10 sites, respectively). Relatively low allelic frequencies of ace-1 (R) were detected in four sites where this assessment was conducted. Evidence of elevated insecticide metabolism, based on oxidase, GSTs and esterase detoxification, was also documented. CONCLUSION: Multiple insecticide-resistance mechanisms have evolved in An. coluzzii, An. gambiae s.s. and An. arabiensis in Mali. These include at least two target site modifications: kdr, and ace-1 (R) , as well as elevated metabolic detoxification systems (monooxygenases and esterases). The selection pressure for resistance could have risen from the use of these insecticides in agriculture, as well as in public health. Resistance management strategies, based on routine resistance monitoring to inform insecticide-based malaria vector control in Mali, are recommended.

Global Call to Action: maximize the public health impact of intermittent preventive treatment of malaria in pregnancy in sub-Saharan Africa.

Intermittent preventive treatment of malaria in pregnancy is a highly cost-effective intervention which significantly improves maternal and birth outcomes among mothers and their newborns who live in areas of moderate to high malaria transmission. However, coverage in sub-Saharan Africa remains unacceptably low, calling for urgent action to increase uptake dramatically and maximize its public health impact. The 'Global Call to Action' outlines priority actions that will pave the way to success in achieving national and international coverage targets. Immediate action is needed from national health institutions in malaria-endemic countries, the donor community, the research community, members of the pharmaceutical industry and private sector, along with technical partners at the global and local levels, to protect pregnant women and their babies from the preventable, adverse effects of malaria in pregnancy.

Global Call to Action to scale-up coverage of intermittent preventive treatment of malaria in pregnancy: seminar report.

In 2014, a global 'Call to Action' seminar for the scale-up of intermittent preventive treatment of malaria in pregnancy was held during the 63rd Annual Meeting of the American Society of Tropical Medicine and Hygiene. This report summarizes the presentations and main discussion points from the meeting.

Spring Forest Qigong and chronic pain: making a difference.

PURPOSE: Research completed in Asia on various forms of qigong over time has repeatedly linked the practice to positive health outcomes. To demonstrate that Spring Forest Qigong (SFQ) knowledge is easily accessible, promotes self-efficacy, and has measurable health benefits, a pilot study on SFQ and chronic pain was designed. DESIGN: This mixed-methods study oriented 122 subjects to Level 1 SFQ. METHOD: Participants were required to complete four symptom surveys (including the Visual Analog Scale), attend three group meetings (beginning, middle, end of study), practice SFQ for 30 minutes per day for 8 weeks, and keep a practice record. FINDINGS: Pearson correlation coefficients were computed pairwise between the symptom surveys. Pearson's chi-square tests were used to assess the association of these variables between the four survey time points, with statistical significance assessed at α =.05. The hypothesis was statistically supported. The active exercise and the meditation aspects of SFQ are effective self-care modalities for persons with perceived chronic physical pain and/or emotional distress. CONCLUSIONS: Subjects (n = 86) demonstrated significant improvement both statistically and anecdotally during the study period. Clinical relevance : Findings indicate that health care providers could promote this promising evidenced-based modality for adults to actualize health promotion practices.