How many human pathogens are there in Laos? An estimate of national human pathogen diversity and analysis of historical trends

Abstract

ObjectiveThe emergence of infectious diseases pose major global health threats. Estimates of total in-country human pathogen diversity, and insights as to how and when species were described through history, could be used to estimate the probability of new pathogen discoveries. Data from the Lao People’s Democratic Republic (Laos) were used in this proof-of-concept study to estimate national human pathogen diversity and to examine historical discovery rate drivers.MethodsA systematic survey of the French and English scientific and grey literature of pathogen description in Laos between 1874 and 2017 was conducted. The first descriptions of each known human pathogen in Laos were coded according to the diagnostic evidence available. Cumulative frequency of discovery across time informed the rate of discovery. Four distinct periods of health systems development in Laos were identified prospectively and juxtaposed to the unmodelled rate of discovery. A model with a time-varying rate of discovery was fitted to these data using a Markov-Chain- Monte-Carlo technique.ResultsFrom 6456 pathogen descriptions, 245 discoveries of known human pathogens in Laos, including repeat discoveries using different grades of evidence, were identified. The models estimate that the Laos human pathogen species diversity in 2017 is between 169 and 206. During the last decade, there has been a 33-fold increase in the discovery rate coinciding with the strengthening of medical research and microbiology.ConclusionDiscovery curves can be used to model and estimate country-level human pathogen diversity present in a territory. Combining this with historical assessment improves the understanding of the factors affecting local pathogen discovery.PROSPERO registration numberA protocol of this work was registered on PROSPERO (ID:CRD42016046728).

Antimicrobial use and resistance data in human and animal sectors in the Lao PDR: evidence to inform policy

“…Diverse other infectious diseases are common in Laos, 47 but there are very limited AMR data available. Intrinsic AMR is important for melioidosis and rickettsial diseases, reducing the spectrum of efficacious antibiotic therapy.…”

“…The majority (49%) of data sources on AMR and AMU were from one site, at LOMWRU/ Mahosot Hospital. Though the number of publications on infectious diseases in Laos has greatly increased since 2000, 47 88 there are few articles that specifically describe the AMU and AMR situations in Laos. Fifteen percent of the data sources on AMR and AMU in this review were not peer-reviewed.…”

“…No second-line TB drug (kanamycin, capreomycin and ofloxacin) resistance was reported. 46 AMR of other bacteria of local and regional importance Diverse other infectious diseases are common in Laos, 47 but there are very limited AMR data available. Intrinsic AMR is important for melioidosis and rickettsial diseases, reducing the spectrum of efficacious antibiotic therapy.…”