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To understand how malaria could be eliminated in the original hyperendmic area for malaria along international borders in Yunnan Province, malaria situation and control were described on the basis of seven phases. At last the experiences and lessons of the program that reduced border malaria from hyperendmicity to malaria-free status were summarized. Malaria control and elimination area were particularly difficult in the Yunnan border. The achievement can be attributed to high political commitment, strategic and technical innovations based on the actual locality, effective collaboration and communication with neighbouring countries to carry out cross border interventions. Other border areas might perform their own pilot interventions based on their local context, including malaria burden, governing system, health service structure contextualized based on their socioeconomic development and ecology, and then a local decision could be made according to their own trial results. [ABSTRACT FROM AUTHOR]

Background: Eliminating malaria and preventing re-establishment of malaria transmission in border areas requires universal coverage of malaria surveillance and a rapid response to any threats (i.e. malaria cues) of re-establishing transmission. Main text: Strategy 1: Intensive interventions within 2.5 km-wide perimeter along the border to prevent border-spill malaria. The area within 2.5 km along the international border is the travel radius of anopheline mosquitoes. Comprehensive interventions should include: (1) proactive and passive case detection, (2) intensive vector surveillance, (3) evidence-based vector control, and (4) evidence-based preventative treatment with anti-malarial drugs. Strategy 2: Community-based malaria detection and screening of migrants and travellers in frontier townships. Un-permitted travellers cross borders frequently and present in frontier townships. Maintenance of intensified malaria surveillance should include: (1) passive malaria detection in the township hospitals, (2) seek assistance from villager leaders and health workers to monitor cross border travellers, and refer febrile patients to the township hospitals and (3) the county's Centre for Disease Control and Prevention maintain regular proactive case detection. Strategy 3: Universal coverage of malaria surveillance to detect malaria cues. Passive detection should be consolidated into the normal health service. Health services personnel should remain vigilant to ensure universal coverage of malaria detection and react promptly to any malaria cues. Strategy + 1: Strong collaborative support with neighbouring countries. Based on the agreement between the two countries, integrated control strategies should be carried out to reduce malaria burden for both countries. There should be a clear focus on the border areas between neighbouring countries. Conclusion: The 3 + 1 strategy is an experience summary of border malaria control and elimination, and then contributed to malaria elimination in Yunnan's border areas, China. Nevertheless, Yunnan still has remaining challenges of re-establishment of malaria transmission in the border areas, and the 3 + 1 strategy should still be carried out. [ABSTRACT FROM AUTHOR]

Background: Eradication of infectious disease is the sanctified public health and sustainable development goal around the world. Main body: Three antimalarial barriers were developed to control imported malarial cases, and an effective surveillance strategy known as the "1–3–7 approach" was developed to eliminate malaria from the Chinese population. From 2011 to 2019, 5254 confirmed malaria cases were reported and treated in Yunnan Province, China. Among them, 4566 cases were imported from other countries, and 688 cases were indigenous from 2011 to 2016. Since 2017, no new local malarial case has been reported in China. Thus, malaria has been completely eliminated in Yunnan Province. However, malaria is detected in overseas travellers on a regular basis, such as visitors from neighbouring Myanmar. Conclusion: Hence, the strategies should be further strengthened to maintain a robust public health infrastructure for disease surveillance and vector control programs in border areas. Such programs should be supported technically and financially by the government to avert the possibility of a malarial resurgence in Yunnan Province. [ABSTRACT FROM AUTHOR]

Metasequoia glyptostroboides Hu et W.C.Cheng (Cupressaceae) is a relic plant with a narrow natural distribution in central China. Historically, the genus Metasequoia Hu et W.C.Cheng has rich fossil records from the Cretaceous to the Pleistocene in the Northern Hemisphere, but fossil records of Metasequoia in China are still rare, which limits our knowledge of its biogeographic history under paleoenvironmental changes. Here, we describe leaves including cuticles and ovuliferous cones from the middle Miocene of Zhenyuan, Yunnan, Southwest China, comprising the southernmost fossil record of the genus worldwide. Judging by the great morphological similarity between these fossils and extant M. glyptostroboides , we identify them as Metasequoia sp. (cf. Metasequoia glyptostroboides). The material documents obviously a long lasting morphological stasis within the genus. Metasequoia sp. (cf. M. glyptostroboides) considerably expands the spatial distribution range of Metasequoia in the geological past. Furthermore, possible reasons for its disappearance in Southwest China are discussed. Together with other evidence, it is concluded that the disappearance of Metasequoia from Southwest China might be related to the evolutionary stasis of Metasequoia , most likely preventing necessary adaptations of the plants to increasing winter and spring aridity induced by the intensification of the Asian monsoon in this region during the Neogene. • Metasequoia is found from the middle Miocene of southwestern China. • It shows morphological similarity to extant M. glyptostroboides. • Evolutionary stasis of Metasequoia and the intensification of the Asian monsoon might cause its disappearance. [ABSTRACT FROM AUTHOR]

Yunnan, southwestern China, represents a modern biodiversity center for Rubus (Rosaceae). The history for this high modern diversity remains poorly known due to the lack of fossil evidence. In this report, fossil pyrenes of Rubus are taxonomically studied from the late Pliocene (Piacenzian) of Lanping County, northwestern Yunnan. These pyrenes show a greater morphological variation than that of extant Rubus pyrenes within the same species, indicating that they belong to different taxa of Rubus . Based on comparisons with both modern and other fossil species, our fossil pyrenes are assigned to five taxa, including a newly established one, Rubus lanpingensis nov. sp. These fossils suggest a somewhat high species diversity of Rubus in Lanping, a small area in northwestern Yunnan, during the late Pliocene. This provides the first fossil perspective for an understanding of the historical background of the modern Rubus diversity in a limited geographic area of Yunnan. The inferred palaeobiodiversity is probably associated with a large environmental heterogeneity in a limited area of Yunnan at that time. [ABSTRACT FROM AUTHOR]

In southwestern China and Southeast Asia modern geology and topography have been influenced strongly by the collision between the Indian and Eurasian plates. The southeastern margin of the Tibetan Plateau is well known for its high biodiversity and diverse vegetation types. While the present diversity is explained by the geological history of this region, to date no study has looked at how past vegetation was shaped by geological and topographical history. In this study, we focus on three coeval late Miocene leaf assemblages from Yunnan: Lincang, Xiaolongtan and Xianfeng. The palaeoelevation of these three sites is reconstructed using enthalpy as a palaeoaltimeter. Enthalpy at the fossil site is reconstructed based on leaf physiognomy; the difference between this enthalpy and enthalpy at sea-level is used as a proxy for altitude. The palaeoaltitudes are resolved as 214 ± 901 m asl for Lincang, 530 ± 901 m asl for Xiaolongtan, and 1936 ± 901 m asl for Xianfeng. The floristic components of these floras are analysed for their geographical elements. There is a gradient in the percentage of tropical genera between the three floras from Lincang, at the lowest elevation, to Xianfeng, at the highest level. For Lincang, this percentage exceeds the threshold used to define present day tropical regions. Our results demonstrate that there was already a floristic differentiation in Yunnan during the late Miocene. Floras with tropical affinities were at low altitude, whereas floras with temperate affinities were at high altitude. With the later uplift of southern Yunnan, floras with tropical affinities retreated to the south where they are still present. The uplift framework reconstructed in this paper gives a tectonic context for further studies on the impact of uplift on biodiversity. [ABSTRACT FROM AUTHOR]

Abstract: The Miocene Lincang leaf assemblage is used in this paper as proxy data to reconstruct the palaeoclimate of southwestern Yunnan (SW China) and the evolution of monsoon intensity. Three quantitative methods were chosen for this reconstruction, i.e. Leaf Margin Analysis (LMA), Climate Leaf Analysis Multivariate Program (CLAMP), and the Coexistence Approach (CA). These methods, however, yield inconsistent results, particularly for the precipitation, as also shown in European and other East Asian Cenozoic floras. The wide range of the reconstructed climatic parameters includes the Mean Annual Temperature (MAT) of 18.5–24.7°C and the Mean Annual Precipitation (MAP) of 1213–3711mm. Compared with the modern Lincang climate (MAT, 17.3°C; MAP, 1178.7mm), the Miocene climate is slightly warmer, wetter and has a higher temperature seasonality. A detailed comparison on the palaeoclimatic variables with the coeval Late Miocene Xiaolongtan flora from the eastern part of Yunnan allows us to investigate the development and interactions of both South Asian and East Asian monsoons during the Late Miocene in southwest China, now under strong influence of these monsoon systems. Our results suggest that the monsoon climate has already been established in southwest Yunnan during the Late Miocene. Furthermore, our results support that both Southeast Asian and East Asian monsoons co-occurred in Yunnan during the Late Miocene. [Copyright &y& Elsevier]

Abstract: The late Miocene Xiaolongtan megaflora from Kaiyuan in southeast Yunnan (23°48′45″N, 103°11′52″E, 1050 m a.s.l.) was chosen for palaeoclimatic reconstruction using three quantitative techniques, i.e. the Coexistence Approach (CA), Leaf Margin Analysis (LMA), and the Climate–Leaf Analysis Multivariate Program (CLAMP). The reconstructed climatic parameters are also compared with those of the two adjacent Miocene floras currently available in Yunnan, i.e. the early to middle Miocene carpological Mangdan flora (24°24′N, 97°49′E, 1620 m a.s.l.) and the late Miocene Lühe palynoflora (25°10′N, 101°22′E, 1930 m a.s.l.). Quantitative analyses of the Xiaolongtan flora supports the previous qualitative results of a southern, humid subtropical climate, being more humid and having a slightly higher mean annual temperature (MAT) than today. The MATs calculated by CA, LMA, and CLAMP overlap (16.7–19.2 °C, 22.3±2.05 °C, 18.1±1.2 °C, respectively) and are close to the present day value (19.7 °C). The overlapping of temperatures derived using the three techniques is unusual and probably related to the low latitude of the Xiaolongtan area and the southern subtropical nature of its vegetation. Both the mean temperatures of the warmest month (WMT) and of the coldest month (CMT) reconstructed by CA (WMT=25.4–26.0 °C, CMT=7.7–8.7 °C) and CLAMP (WMT=25.9±1.6 °C, CMT=10.8±1.9 °C) are similar to those of today (WMT=24.3 °C, CMT=12.8 °C), but great changes appear in the mean annual precipitation (MAP). The CLAMP results suggest a higher precipitation (1964±335.9 mm) than CA (1215–1639 mm), but they are much higher than the present MAP (820.5 mm). This is consistent with results from the Lühe palynoflora, which also developed under a warmer subtropical climate with higher precipitation (803.6–1254.7 mm) than that of today (815.9 mm). In contrast, the Mangdan flora, situated in a more complicated topographic region to the west of Xiaolongtan and near the Sino-Myanmar border, implies a slightly lower precipitation (1170–1300 mm) than that of today (1300–1400 mm). Overall, the wetter climate during the late Miocene around the Xiaolongtan area suggests that the Himalayas had not yet uplifted to its present altitudes at that time. [Copyright &y& Elsevier]