1921
Volume 97, Issue 5
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645

Abstract

Abstract.

Malaria infections may be symptomatic, leading to treatment, or “asymptomatic,” typically detected through active surveillance, and not leading to treatment. Malaria elimination may require purging both types of infection. Using detection methods with different sensitivities, we conducted a cross-sectional study in two rural communities located along the border between China’s Yunnan Province and Myanmar’s Shan and Kachin States, to estimate the prevalence of asymptomatic and symptomatic malaria. In Mong Pawk, all infections detected were asymptomatic, and the prevalence of was 0.3%, 4.3%, 4.0%, and 7.8% by light microscopy, rapid diagnostic test (RDT), conventional polymerase chain reaction (cPCR), and multiplexed real-time PCR (RT-PCR), respectively, and prevalence was 0% by all detection methods. In Laiza, of 385 asymptomatic participants, 2.3%, 4.4%, and 12.2% were positive for by microscopy, cPCR, and RT-PCR, respectively, and 2.3% were -positive only by RT-PCR. Of 34 symptomatic participants in Laiza, 32.4% were positive by all detection methods. Factors associated with infection included gender (males higher than females, = 0.014), and young age group (5–17 age group compared with others, = 0.0024). Although the sensitivity of microscopy was adequate to detect symptomatic infections, it missed the vast majority (86.5%) of asymptomatic infections. Although molecular detection methods had no advantage over standard microscopy or RDT diagnosis for clinically apparent infections, malaria elimination along the Myanmar–China border will likely require highly sensitive surveillance tools to identify asymptomatic infections and guide targeted screen-and-treat interventions.

[open-access] This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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2017-11-22
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References

  1. World Health Organization, 2015. Global Technical Strategy for Malaria 2016–2030. Geneva, Switzerland: WHO.
  2. Hsiang MS, Gosling RD, , 2015. Striding toward malaria elimination in China. Am J Trop Med Hyg 93: 203204.[Crossref]
  3. Qi G, , 2011. Opportunities and challenges of malaria elimination in China. Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi 23: 347349.
  4. Yang WZ, Zhou XN, , 2016. New challenges of malaria elimination in China. Zhonghua Yu Fang Yi Xue Za Zhi 50: 289291.
  5. Xu J, Liu H, , 2012. The challenges of malaria elimination in Yunnan Province, People’s Republic of China. Southeast Asian J Trop Med Public Health 43: 819824.
  6. malERA, 2011. A research agenda for malaria eradication: drugs. PLoS Med 8: e1000402.
  7. Chen I, Clarke SE, Gosling R, Hamainza B, Killeen G, Magill A, O’Meara W, Price RN, Riley EM, , 2016. “Asymptomatic” malaria: a chronic and debilitating infection that should be treated. PLoS Med 13: e1001942.[Crossref]
  8. Lindblade KA, Steinhardt L, Samuels A, Kachur SP, Slutsker L, , 2013. The silent threat: asymptomatic parasitemia and malaria transmission. Expert Rev Anti Infect Ther 11: 623639.[Crossref]
  9. Imwong M, ., 2015. The epidemiology of subclinical malaria infections in South-East Asia: findings from cross-sectional surveys in Thailand-Myanmar border areas, Cambodia, and Vietnam. Malar J 14: 381.[Crossref]
  10. Canier L, ., 2015. Malaria PCR detection in Cambodian low-transmission settings: dried blood spots versus venous blood samples. Am J Trop Med Hyg 92: 573577.[Crossref]
  11. Imwong M, Hanchana S, Malleret B, Renia L, Day NP, Dondorp A, Nosten F, Snounou G, White NJ, , 2014. High-throughput ultrasensitive molecular techniques for quantifying low-density malaria parasitemias. J Clin Microbiol 52: 33033309.[Crossref]
  12. Adams M, ., 2015. An ultrasensitive reverse transcription polymerase chain reaction assay to detect asymptomatic low-density Plasmodium falciparum and Plasmodium vivax infections in small volume blood samples. Malar J 14: 520.[Crossref]
  13. Lwin KM, Imwong M, Suangkanarat P, Jeeyapant A, Vihokhern B, Wongsaen K, Snounou G, Keereecharoen L, White NJ, Nosten F, , 2015. Elimination of Plasmodium falciparum in an area of multi-drug resistance. Malar J 14: 319.[Crossref]
  14. World Health Organization, 2011 . Malaria Rapid Diagnostic Test Performance: Results of WHO Product Testing of Malaria RDTs: Round 3 (2010–2011). Geneva, Switzerland: WHO.
  15. Snounou G, Singh B, , 2002. Nested PCR analysis of Plasmodium parasites. Methods Mol Med 72: 189203.
  16. Shokoples SE, Ndao M, Kowalewska-Grochowska K, Yanow SK, , 2009. Multiplexed real-time PCR assay for discrimination of Plasmodium species with improved sensitivity for mixed infections. J Clin Microbiol 47: 975980.[Crossref]
  17. Ariey F, ., 2014. A molecular marker of artemisinin-resistant Plasmodium falciparum malaria. Nature 505: 5055.[Crossref]
  18. Khairnar K, Martin D, Lau R, Ralevski F, Pillai DR, , 2009. Multiplex real-time quantitative PCR, microscopy and rapid diagnostic immuno-chromatographic tests for the detection of Plasmodium spp.: performance, limit of detection analysis and quality assurance. Malar J 8: 284.[Crossref]
  19. Bousema T, Okell L, Felger I, Drakeley C, , 2014. Asymptomatic malaria infections: detectability, transmissibility and public health relevance. Nat Rev Microbiol 12: 833840.[Crossref]
  20. Imwong M, ., 2016. Numerical distributions of parasite densities during asymptomatic malaria. J Infect Dis 213: 13221329.[Crossref]
  21. Tripura R, ., 2016. Persistent Plasmodium falciparum and Plasmodium vivax infections in a western Cambodian population: implications for prevention, treatment and elimination strategies. Malar J 15: 181.[Crossref]
  22. Shannon KL, ., 2016. Subclinical Plasmodium falciparum infections act as year-round reservoir for malaria in the hypoendemic Chittagong Hill districts of Bangladesh. Int J Infect Dis 49: 161169.[Crossref]
  23. Delacollette C, ., 2009. Malaria trends and challenges in the Greater Mekong Subregion. Southeast Asian J Trop Med Public Health 40: 674691.
  24. World Health Organization, 2015. World Malaria Report 2015: Summary. Geneva, Switzerland: WHO.
  25. Wang RB, Zhang J, Zhang QF, , 2014. Malaria baseline survey in four special regions of northern Myanmar near China: a cross-sectional study. Malar J 13: 302.[Crossref]
  26. Xu JW, Liu H, Zhang Y, Guo XR, Wang JZ, , 2015. Risk factors for border malaria in a malaria elimination setting: a retrospective case-control study in Yunnan, China. Am J Trop Med Hyg 92: 546551.[Crossref]
  27. Xu JW, Liu H, , 2016. The relationship of malaria between Chinese side and Myanmar’s five special regions along China-Myanmar border: a linear regression analysis. Malar J 15: 368.[Crossref]
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  • Received : 05 Mar 2017
  • Accepted : 17 Apr 2017

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