The black rat(Rattus rattus)poses a severe threat to food security and public health in Madagascar,where it is a major cause of pre-and post-harvest crop losses and an important reservoir for many zoonotic diseases,in...The black rat(Rattus rattus)poses a severe threat to food security and public health in Madagascar,where it is a major cause of pre-and post-harvest crop losses and an important reservoir for many zoonotic diseases,including plague.Elsewhere,ecologically based rodent management(EBRM)strategies have been developed using ecologi-cal information to inform decisions on where and when to target control.EBRM could deliver improved health and well-being outcomes in Madagascar if adapted to the local ecological context.Using data collected from removal studies,we explored spatio-temporal patterns in the breeding activity of the black rat(R.rattus)in domestic and agricultural habitats across Madagascar and investigated to what extent these trends are influenced by rainfall and rat density.We identified clear spatio-temporal variation in the seasonality of R.rattus reproduction.Reproduction was highly seasonal both inside and outside of houses,but seasonal trends varied between these two habitats.Sea-sonal trends were explained,in part,by variation in rainfall;however,the effect of rainfall on reproductive rates did itself vary by season and habitat type.A decline in breeding intensity with increasing rat density was recorded outside of houses.This has important implications for control,as populations may compensate for removal through increased reproduction.We recommend that sustained control initiated before the main breeding season,combined with improved hygiene and adequate rodent-proofing in homes and grain stores,could curtail population growth and reduce pre-and post-harvest losses provided that these measures overcome the compensatory response of rodent populations.展开更多
Rodents represent a serious threat to food security and public health.The extent to which rodent control can mitigate the risk from rodent-borne disease depends on both the effectiveness of control in reducing rodent ...Rodents represent a serious threat to food security and public health.The extent to which rodent control can mitigate the risk from rodent-borne disease depends on both the effectiveness of control in reducing rodent abundance and the impact on disease epidemiology.Focusing on a plague-endemic region of Madagascar,this study compared the effectiveness of 3 methods:live-traps,snap-traps,and rodenticides.Control interventions were implemented inside houses between May and October 2019.Tracking tiles monitored rodent abundance.Rodent fleas,the vector involved in plague transmission,were collected.Rodent populations consisted of Rattus rattus and Mus musculus.In terms of trap success,we found that our live-trap regime was more effective than snap-traps.While all 3 control strategies appeared to reduce in-house rodent activity in the short term,we found no evidence of a longer-term effect,with in-house rodent abundance in treated sites comparable to non-treatment sites by the following month.Endemic flea,Synopsyllus fonquerniei,is a key plague vector usually found on rats living outdoors.Although we found no evidence that its abundance inside houses increased following control,this may have been due to a lack of power caused by significant variation in S.fonquerniei abundance.The presence of S.fonquerniei in houses was more likely when S.fonquerniei abundance on outdoor rats was higher,which in turn correlated with high rat abundance.Our results emphasize that control strategies need to consider this connectivity between in-house rat–flea populations and the outdoor populations,and any potential consequences for plague transmission.展开更多
基金This work was also supported by the Wellcome Trust[095171/Z/10/Z]the Medical Research Council[MR/T029862/1]by the National Institute for Health Research(NIHR)(using the UK’s Official Development Assistance[ODA]Fund-ing)and Wellcome[219532/Z/19/Z]under the NIHR-Wellcome Partnership for Global Health Research.
文摘The black rat(Rattus rattus)poses a severe threat to food security and public health in Madagascar,where it is a major cause of pre-and post-harvest crop losses and an important reservoir for many zoonotic diseases,including plague.Elsewhere,ecologically based rodent management(EBRM)strategies have been developed using ecologi-cal information to inform decisions on where and when to target control.EBRM could deliver improved health and well-being outcomes in Madagascar if adapted to the local ecological context.Using data collected from removal studies,we explored spatio-temporal patterns in the breeding activity of the black rat(R.rattus)in domestic and agricultural habitats across Madagascar and investigated to what extent these trends are influenced by rainfall and rat density.We identified clear spatio-temporal variation in the seasonality of R.rattus reproduction.Reproduction was highly seasonal both inside and outside of houses,but seasonal trends varied between these two habitats.Sea-sonal trends were explained,in part,by variation in rainfall;however,the effect of rainfall on reproductive rates did itself vary by season and habitat type.A decline in breeding intensity with increasing rat density was recorded outside of houses.This has important implications for control,as populations may compensate for removal through increased reproduction.We recommend that sustained control initiated before the main breeding season,combined with improved hygiene and adequate rodent-proofing in homes and grain stores,could curtail population growth and reduce pre-and post-harvest losses provided that these measures overcome the compensatory response of rodent populations.
基金This work was supported by a Directorate General for International Relations and Strategy grant(2018-SB-024-18SSEOC049-PMG7-SSA5-IPMMADAGASCAR)covering the project“Développement de contre-mesures médicalesàla pesteàMadagascar”with scientific support of IRBA(French Armed Forces Biomedical Research Institute),within the framework of French MoD’s involvement in G7 Global partnershipThis research was also funded in part by the Wellcome Trust[095171/Z/10/Z]and the Institut Pasteur de Madagascar.For the purpose of Open Access,the authors have applied a CC BY public copyright license to any Author Accepted Manuscript version arising from this submissionK.S.was supported by the Biotechnology and Biological Sciences Research Council(BBSRC)under the EastBio DTP(grant number BB/M010996/1).
文摘Rodents represent a serious threat to food security and public health.The extent to which rodent control can mitigate the risk from rodent-borne disease depends on both the effectiveness of control in reducing rodent abundance and the impact on disease epidemiology.Focusing on a plague-endemic region of Madagascar,this study compared the effectiveness of 3 methods:live-traps,snap-traps,and rodenticides.Control interventions were implemented inside houses between May and October 2019.Tracking tiles monitored rodent abundance.Rodent fleas,the vector involved in plague transmission,were collected.Rodent populations consisted of Rattus rattus and Mus musculus.In terms of trap success,we found that our live-trap regime was more effective than snap-traps.While all 3 control strategies appeared to reduce in-house rodent activity in the short term,we found no evidence of a longer-term effect,with in-house rodent abundance in treated sites comparable to non-treatment sites by the following month.Endemic flea,Synopsyllus fonquerniei,is a key plague vector usually found on rats living outdoors.Although we found no evidence that its abundance inside houses increased following control,this may have been due to a lack of power caused by significant variation in S.fonquerniei abundance.The presence of S.fonquerniei in houses was more likely when S.fonquerniei abundance on outdoor rats was higher,which in turn correlated with high rat abundance.Our results emphasize that control strategies need to consider this connectivity between in-house rat–flea populations and the outdoor populations,and any potential consequences for plague transmission.