An innovative three-layer strategy in response to a quartan malaria outbreak among forest goers in Hainan Island,China:a retrospective study

Background:An outbreak of Plasmodium malariae infection among forest goers in Sanya City of Hainan Island,China was reported in 2015.In response to this outbreak,an innovative three-layer strategy(TLS)targeted forest goers was adapted based on the 1-3-7 approach.Main text:Key elements of TLS are:(i)The village with fve malaria cases and adjacent villages were set as the frst layer.All residents including forest goers were taken as the high-risk population(HRP).Active case detection(ACD)by blood smear microscopy and PCR was selected as the primary measure,and passive case detection(PCD)as complementary measure.One case was identifed under TLS implementation.(ii)The township with cases(Gaofeng Town)and the nearby towns were chosen as the second layer.Only forest goers were screened by ACD,while PCD as a routine screening method.7831 blood smears collected by ACD and PCD and tested with negative results.(iii)The city with cases(Sanya City)and others 12 counties/county-level cities were selected as the third layer.Malaria cases were monitored passively.A total of 77,555 blood slides were screened by PCD with zero positive sample.For each layer,the malaria vector mosquitoes were monitored using light traps,cattle-baited/human-bait traps.Anopheles minimus(dominant species),An.sinensis and An.dirus were captured.Vector control measures mainly include insecticide residual spraying and long-lasting insecticide nets.The capacity of clinicians,public health practitioners and laboratory technicians has been improved through training.During 2016‒2018,TLS and chemoprophylaxis were implemented in the same areas.In the frst layer,all residents were monitored by ACD,and malaria chemoprophylaxis were distributed,89.5%of forest goers were using chemoprophylaxis against malaria.The blood smears(3126 by ACD plus 1516 by PCD)were with zero positive results.Chemoprophylaxis and ACD were ofered to forest goers once a year,and PCD in residents as a complementary measure in the second and third layer,77.8%and 95.1%of forest goers received chemoprophylaxis.In each layer,vector surveillance and control of malaria and trainings for medical staf Conclusions:TLS was efective in blocking the outbreak by P.malariae among forest goers in Hainan in malaria elimination stage.However,whether it could prevent the malaria resurgence in the post-elimination phase needs to be further assessed.

Elevational patterns and ecological determinants of mean family age of angiosperm assemblages in temperate forests within Mount Taibai, China

Aims Species assembly is shaped by the interactions among ecological and evolutionary processes.By integrating the niche conservatism and evolutionary history,the tropical niche conservatism hypoth-esis(TCH)has clarified species latitudinal diversity gradient at large scales.One of the TCH’s central predictions,though lack-ing empirical evidence,implies that positive relationship between clade age and temperature along the altitudinal gradient should also be observed.Thus,we aim to test this prediction using a data set derived from forest communities of Mt.Taibai,central China.Methods We systematically established 49 plots(20 m×30 m)along the north slope on Mt.Taibai,China.We calculated the mean family age(MFA)and its corresponding standardized values through rarefi-cation and standardization,for woody and herbaceous angiosperm assemblages in each community respectively.Generalized linear models with Akaike weight and correlation analysis was used to evaluate the relationships between MFA with seven environmental predictors.Important Findings For both woody and herbaceous assemblages,the standardized MFA showed significant decreasing tendencies along the eleva-tional gradient and positive associations with minimum temperature(measured as mean temperature of the coldest month).Additionally,minimum temperature is the dominant predictor compared with the others in the regression models.These findings are generally con-sistent with the age-related predictions of the TCH,but are contrary to the results of related studies conducted in tropical regions.