Prevalence of Clinical and Subclinical Plasmodium falciparum and Plasmodium vivax Malaria in Two Remote Rural Communities on the Myanmar–China Border

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 Plasmodium falciparum 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 Plasmodium vivax prevalence was 0% by all detection methods. In Laiza, of 385 asymptomatic participants, 2.3%, 4.4%, and 12.2% were positive for P. vivax by microscopy, cPCR, and RT-PCR, respectively, and 2.3% were P. falciparum-positive only by RT-PCR. Of 34 symptomatic participants in Laiza, 32.4% were P. vivax-positive by all detection methods. Factors associated with infection included gender (males higher than females, P = 0.014), and young age group (5–17 age group compared with others, P = 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.

Prevalence of Asymptomatic Malaria among Children in the Tamale Metropolis: How Does the PfHRP2 CareStart™ RDT Perform against Microscopy?

“…Using microscopy in the current study, the overall prevalence of malaria was lower compared to RDT. is is consistent with recent studies by Sumari et al [11] and Huang et al [21] but contrary to results of a study in Myanmar where microscopy produced a higher prevalence than RDT [22]. e microscopic prevalence found in this current study is far lower than the 56% reported in 2010 and 27.5% in 2017 during a similar dry season study in the northern part of Ghana [18,23].…”

“…Evaluation of gender as a biological factor in asymptomatic malaria is, however, beyond the scope of this present study and therefore recommended for further studies. Nevertheless, in Myanmar, Huang et al [21] and Zaw et al [22] separately reported a higher parasite prevalence among asymptomatic males. Likewise, Kiemde et al [25] found asymptomatic malaria to be prevalent among males using both microscopy and RDT.…”

Bayesian spatiotemporal analysis of malaria infection along an international border: Hlaingbwe Township in Myanmar and Tha-Song-Yang District in Thailand

“…A few studies of the entomological determinants of malaria transmission in the same areas as this study along the Thai–Myanmar border also reported that Anopheles mosquitoes exhibited an outdoor and early biting pattern with active timing between 06:00 and 07:00 [ 53 , 54 ]. Several studies have reported high malaria morbidity among children [ 55 , 56 ]; interestingly, one study in the Laiza refugee camp along the Myanmar–China border [ 57 ] speculated that daytime malaria transmission might occur near the primary school attended by younger children. It would be interesting to conduct an entomological investigation to explore this hypothesis in Tha-Song-Yang District.…”

The health beliefs, dengue knowledge and control behaviors among internally displaced persons versus local residents in Kachin Special Region II, Myanmar

“…DF is still one of the major tropical diseases and an increasing threat to public health in the world [7,8], but the impact of dengue on local public health is still being neglected now. While extensive investigations about malaria have been done in the KSR2, Myanmar [2,3,[9][10][11][12][13][14][15][16][17][18], studies on DF are still unavailable.…”