Biology subjects

Esquivel Gomez, L. R.

Publications and source records attributed to Esquivel Gomez, L. R..

2 recordsLinked to original sources

bioRxiv2025

The temperature sensitivity of arboviral disease extrinsic incubation periods: a systematic review

BackgroundArboviral diseases are an increasing global public health concern, driven by both human and environmental factors. A key parameter shaping transmission is the extrinsic incubation period (EIP)--the time between a mosquito acquiring a virus and becoming infectious--which is strongly influenced by temperature. However, the temperature-EIP relationship remains poorly characterized across arboviruses and mosquito species. MethodsWe conducted the first systematic review of laboratory studies evaluating temperature effects on EIP-related outcomes across all reported mosquito-arbovirus pairings. We searched three databases and extracted data on transmission efficiency (TE), applying linear regression models adjusted for diurnal temperature range and viral dose. Studies where TE could not be extracted were synthesized narratively. ResultsOur synthesis included 60 studies covering 17 arboviral diseases and 20 mosquito species. We found substantial heterogeneity in temperature effects on TE. While CHIKV, ZIKV, DENV, and WNV generally showed increased TE and shorter EIP at higher temperatures, many viruses--such as SINV, USUV, and BATV--exhibited no clear trends, often due to limited data and small sample sizes. Even across different vectors of the same virus, findings varied widely, reflecting both biological differences and inconsistent experimental designs. ConclusionsThese findings reveal major gaps in our understanding of climate-sensitive arbovirus transmission. Standardization of vector competence experiments and expanded research on neglected viruses are urgently needed. Environmental cofactors beyond temperature--such as humidity and variability--should also be incorporated to improve modelling and support climate-resilient intervention strategies. Author summaryThe burden of disease caused by arboviruses is increasing globally, largely driven by rapid urbanization, climate change, and global mobility. The transmission dynamics of arboviruses are modulated by a parameter known as the extrinsic incubation period, which is driven by environmental factors, especially temperature. However, the extent and direction of this effect has not been well characterized for all viruses, as data is limited and has not been synthesized for many neglected tropical diseases. Our study is the first systematic review to examine the existing evidence of laboratory studies across all studied mosquito species and virus pairings and to provide a comprehensive dataset for future modelling studies. We find that there is significant heterogeneity, not only between viruses, but also within individual vector-virus combinations, and that many arboviruses show no temperature effect. Based on these results, we propose that existing research efforts be standardized, and further research is conducted on emerging and re-emerging arboviruses for better intervention strategies and modelling predictions.

microbiology↗

bioRxiv2022

Phylogenetic analysis of the origin and spread of plague in Madagascar

BackgroundPlague is a zoonotic disease caused by the bacterium Yersinia pestis, highly prevalent in the Central Highlands, a mountainous region in the center of Madagascar. After a plague-free period of over 60 years in the northwestern coast city of Mahajanga, the disease reappeared in 1991 and caused several outbreaks until 1999. Previous research indicates that the disease was reintroduced to the city of Mahajanga from the Central Highlands instead of reemerging from a local reservoir. However, it is not clear how many reintroductions occurred and when they took place. Methodology/Principal findingsIn this study we applied a Bayesian phylogeographic model to detect and date migrations of Y. pestis between the two locations that could be linked to the re-emergence of plague in Mahajanga. Genome sequences of 300 Y. pestis strains sampled between 1964 and 2012 were analyzed. Four migrations from the Central Highlands to Mahajanga were detected. Two resulted in persistent transmission in humans, one was responsible for most of the human cases recorded between 1995 and 1999, while the other produced plague cases in 1991 and 1992. We dated the emergence of the Y. pestis sub-branch 1.ORI3, which is only present in Madagascar and Turkey, to the beginning of the 20th century, using a Bayesian molecular dating analysis. The split between 1.ORI3 and its ancestor lineage 1.ORI2 was dated to the second half of the 19th century. Conclusions/SignificanceOur results indicate that two independent migrations from the Central Highlands caused the plague outbreaks in Mahajanga during the 1990s, with both introductions occurring during the early 1980s. They happened over a decade before the detection of human cases, thus the pathogen likely survived in wild reservoirs until the spillover to humans was possible. This study demonstrates the value of Bayesian phylogenetics in elucidating the re-emergence of infectious diseases. Author summaryIn 1991 human cases of plague were reported in the city of Mahajanga, located in the west coast of Madagascar, after 60 years without human cases. Existing evidence suggests that Yersinia pestis, the causal agent of the disease, was reintroduced to the city from a mountainous region known as the Central Highlands. We performed a phylogeographic analysis on 300 Y. pestis genome sequences to determine how many migrations of the pathogen between the two locations were related to the reappearance of the disease in Mahajanga. The results revealed that two migrations from the Central Highlands were the cause of the outbreaks of plague in the west coast of the country during the 1990s. We also aimed to date the emergence of the Y.pestis variant that circulates in Madagascar and is also present in Turkey. To do this, we conducted a molecular dating analysis using an extended data set of 445 sequences, which contained sequences from Turkey and India (the country from which the pathogen was exported to Madagascar for the first time). The analysis indicated that this particular variant emerged in the first decade of the 20th century.

microbiology↗