@article{fdi:010079538,
  title = {{A}ssociation between the proportion of {P}lasmodium falciparum and {P}lasmodium vivax infections detected by passive surveillance and the magnitude of the asymptomatic reservoir in the community : a pooled analysis of paired health facility and community data},
  author = {{S}tresman, {G}. and {S}epulveda, {N}. and {F}ornace, {K}. and {G}rignard, {L}. and {M}wesigwa, {J}. and {A}chan, {J}. and {M}iller, {J}. and {B}ridges, {D}. {J}. and {E}isele, {T}. {P}. and {M}osha, {J}. and {L}orenzo, {P}. {J}. and {M}acalinao, {M}. {L}. and {E}spino, {F}. {E}. and {T}adesse, {F}. and {S}tevenson, {J}. {C}. and {Q}uispe, {A}. {M}. and {S}iqueira, {A}. and {L}acerda, {M}. and {Y}eung, {S}. {M}. and {S}ovannaroth, {S}. and {P}othin, {E}. and {G}allay, {J}. and {H}amre, {K}. {E}. and {Y}oung, {A}. and {L}emoine, {J}. {F}. and {C}hang, {M}. {A}. and {P}hommasone, {K}. and {M}ayxay, {M}. and {L}andier, {J}ordi and {P}arker, {D}. {M}. and {V}on {S}eidlein, {L}. and {N}osten, {F}. and {D}elmas, {G}. and {D}ondorp, {A}. and {C}ameron, {E}. and {B}attle, {K}. and {B}ousema, {T}. and {G}ething, {P}. and {D}'{A}lessandro, {U}. and {D}rakeley, {C}.},
  editor = {},
  language = {{ENG}},
  abstract = {{B}ackground {P}assively collected malaria case data are the foundation for public health decision making. {H}owever, because of population-level immunity, infections might not always be sufficiently symptomatic to prompt individuals to seek care. {U}nderstanding the proportion of all {P}lasmodium spp infections expected to be detected by the health system becomes particularly paramount in elimination settings. {T}he aim of this study was to determine the association between the proportion of infections detected and transmission intensity for {P}lasmodium falciparum and {P}lasmodium vivax in several global endemic settings. {M}ethods {T}he proportion of infections detected in routine malaria data, {P}({D}etect), was derived from paired household cross-sectional survey and routinely collected malaria data within health facilities. {P}({D}etect) was estimated using a {B}ayesian model in 431 clusters spanning the {A}mericas, {A}frica, and {A}sia. {T}he association between {P}({D}etect) and malaria prevalence was assessed using log-linear regression models. {C}hanges in {P}({D}etect) over time were evaluated using data from 13 timepoints over 2 years from {T}he {G}ambia. {F}indings {T}he median estimated {P}({D}etect) across all clusters was 12.5% ({IQR} 5.3-25.0) for {P} falciparum and 10.1% (5.0-18.3) for {P} vivax and decreased as the estimated log-{PCR} community prevalence increased (adjusted odds ratio [{OR}] for {P} falciparum 0.63, 95% {CI} 0.57-0.69; adjusted {OR} for {P} vivax 0.52, 0.47-0.57). {F}actors associated with increasing {P}({D}etect) included smaller catchment population size, high transmission season, improved care-seeking behaviour by infected individuals, and recent increases (within the previous year) in transmission intensity. {I}nterpretation {T}he proportion of all infections detected within health systems increases once transmission intensity is sufficiently low. {T}he likely explanation for {P} falciparum is that reduced exposure to infection leads to lower levels of protective immunity in the population, increasing the likelihood that infected individuals will become symptomatic and seek care. {T}hese factors might also be true for {P} vivax but a better understanding of the transmission biology is needed to attribute likely reasons for the observed trend. {I}n low transmission and pre-elimination settings, enhancing access to care and improvements in care-seeking behaviour of infected individuals will lead to an increased proportion of infections detected in the community and might contribute to accelerating the interruption of transmission.},
  keywords = {{AMERIQUE} ; {AFRIQUE} ; {ASIE}},
  booktitle = {},
  journal = {{L}ancet {I}nfectious {D}iseases},
  volume = {20},
  numero = {8},
  pages = {953--963},
  ISSN = {1473-3099},
  year = {2020},
  DOI = {10.1016/s1473-3099(20)30059-1},
  URL = {https://www.documentation.ird.fr/hor/fdi:010079538},
}