Recent decades have brought countless outbreaks of infectious disease among wildlife. These events appear to be increasing in frequency and magnitude, but to objectively evaluate whether ecosystems are experiencing rising rates of disease, scientists require historical data on disease abundance. Specimens held in natural history collections represent a chronological archive of life on Earth and may, in many cases, be the only available source of data on historical disease patterns. It is possible to extract information on past disease rates by studying trace fossils (indirect fossilized evidence of an organism's presence or activity, including coprolites or feces), sequencing ancient DNA of parasites, and examining sediment samples, mummified remains, study skins (preserved animal skins prepared by taxidermy for research purposes), liquid‐preserved hosts, and hosts preserved in amber. Such use of natural history collections could expand scientific understanding of parasite responses to environmental change across deep time (that is, over the past several centuries), facilitating the development of baselines for managing contemporary wildlife disease.
Background: The most commonly used diagnostic tool for soil-transmitted helminths (STH) is the Kato-Katz (KK) thick smear technique. However, numerous studies have suggested that the sensitivity of KK can be problematic, especially in low prevalence and low intensity settings. An emerging alternative is quantitative polymerase chain reaction (qPCR). Methods: In this study, both KK and qPCR were conducted on stool samples from 648 participants in an STH epidemiology study conducted in the delta region of Myanmar in June 2016. Results: Prevalence of any STH was 20.68% by KK and 45.06% by qPCR. Prevalence of each individual STH was also higher by qPCR than KK, the biggest difference was for hookworm with an approximately 4-fold increase between the two diagnostic techniques. Prevalence of Ancylostoma ceylanicum, a parasite predominately found in dogs, was 4.63%, indicating that there is the possibility of zoonotic transmission in the study setting. In individuals with moderate to high intensity infections there is evidence for a linear relationship between eggs per gram (EPG) of faeces, derived from KK, and DNA copy number, derived from qPCR which is particularly strong for Ascaris lumbricoides. Conclusions: The use of qPCR in low prevalence settings is important to accurately assess the epidemiological situation and plan control strategies for the 'end game'. However, more work is required to accurately assess STH intensity from qPCR results and to reduce the cost of qPCR so that is widely accessible in STH endemic countries.
The understanding of Earth's biodiversity depends critically on the accurate identification and nomenclature of species. Many species were described centuries ago, and in a surprising number of cases their nomenclature or type material remain unclear or inconsistent. A prime example is provided by Elephas maximus, one of the most iconic and well-known mammalian species, described and named by Linnaeus (1758) and today designating the Asian elephant. We used morphological, ancient DNA (aDNA), and high-throughput ancient proteomic analyses to demonstrate that a widely discussed syntype specimen of E. maximus, a complete foetus preserved in ethanol, is actually an African elephant, genus Loxodonta. We further discovered that an additional E. maximus syntype, mentioned in a description by John Ray (1693) cited by Linnaeus, has been preserved as an almost complete skeleton at the Natural History Museum of the University of Florence. Having confirmed its identity as an Asian elephant through both morphological and ancient DNA analyses, we designate this specimen as the lectotype of E. maximus.
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