THE INFLUENCE OF CLIMATE ON THE SEASONAL PREVALENCE OF PLAGUE IN THE REPUBLIC OF VIETNAM
Abstract
An 8 year study of the influence of climate on the seasonal prevalence of bubonic plague in the Republic of Vietnam has been completed. Climatic conditions were found to influence the course of plague epidemics in 2 ways: 1) by regulating the density of the flea population; and, 2) by regulating the efficiency of Xenopsylla cheopis in transmitting the plague bacillus. Slight variations in temperature, relative humidity, and vapor pressure deficits either permit an epidemic to flourish or cause a decline in its intensity.
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The vast majority of past plague cases have been described in regions where average temperatures are >13°C, with outbreaks occurring when temperature ranges from 24°C to 27°C and a decrease of epidemic activities at higher values.
“Accordingly, the vast majority of past plague cases have been described in those regions where average temperatures are >13°C, with outbreaks occurring when temperature ranges from 24°C to 27°C and a decrease of epidemic activities at higher values [62-64].”
From Fleas infesting pets in the era of emerging extra-intestinal nematodes (2013) · cites this paper as [63]
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NATURAL HISTORY OF PLAGUE: Perspectives from More than a Century of Research
Gage, K. L., & Kosoy, M. (2004) · Annual Review of Entomology · doi:10.1146/annurev.ento.50.071803.130337 · Cited by 733 · see citing works
“Climatic factors appear to be important in many but perhaps not all areas (24, 25, 41, 44, 105, 113, 129).”
BackgroundPlague dynamics are driven by climate variation
Stenseth, N. C., Samia, N. I., Viljugrein, H., Kausrud, K., Begon, M. E., Davis, S., Leirs, H., Dubyanskiy, V. M., Esper, J., Ageyev, V. S., et al. (2006) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.0602447103 · Cited by 317 · see citing works
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“pestis to block the foregut of the flea vector, a prerequisite of transmission, is much greater at 21∞C than at 25∞C or higher (Cavanaugh and Marshall, 1972; Hinnebusch et al., 1998).”
BackgroundTransmission of Flea-Borne Zoonotic Agents
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“Hot and dry days also reduce blockage in fleas [17], and low temperatures delay bacterial proliferation and early-phase transmission by X.”
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“Temperature and relative humidity impact flea survival [5]: survival is in fact inversely proportional to air saturation deficit at a constant temperature [14].”
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“This hypothesis was compelling because it could also explain the decrease in proventricular blockage and flea-borne transmission during hot weather (Cavanaugh and Marshall 1972).”
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“cheopis–borne bubonic plague epidemics rapidly subside with the onset of hot, dry weather [43, 57].”
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“In contrast to the studies from North America, however, in Vietnam most human plague cases have been found to occur in dry seasons (23); the risk of plague increased during dry seasons when rainfall was <10 mm (24), showing that the trophic cascade hypothesis may not be generally valid.”
ResultFeeding behaviour of pathogen-infected vectors
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“The area predicted by the southern subset encompasses northern Viet Nam where plague is known to have occurred (23, 24) and parts of Nepal and northeastern India (which is not inconsistent with ref.”
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“Alternative modes of transmission have been proposed, including the inhalation of infected respiratory droplets or can-nibalization of infected carcasses (Bacot and Martin 1914, Dennis et al. 1999, Pollitzer 1954, Mollaret 1963, Webb et al. 2006, Cavanaugh and Marshall 1972).”
Fleas infesting pets in the era of emerging extra-intestinal nematodes
Traversa, D. (2013) · Parasites & Vectors · doi:10.1186/1756-3305-6-59 · Cited by 53 · see citing works
“Accordingly, the vast majority of past plague cases have been described in those regions where average temperatures are >13°C, with outbreaks occurring when temperature ranges from 24°C to 27°C and a decrease of epidemic activities at higher values [62-64].”
BackgroundRange-wide Determinants of Plague Distribution in North America
Maher, S. P., Ellis, C., Gage, K. L., Enscore, R. E., & Peterson, A. T. (2010) · American Journal of Tropical Medicine and Hygiene · doi:10.4269/ajtmh.2010.10-0042 · Cited by 51 · see citing works
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“Historically, it has been shown that increases in the mean monthly ambient temperature above 27.5 (cid:2) C result in declines in epizootic and human plague activity (Pollitzer 1954, Ca-vanaugh 1971, Cavanaugh and Marshall 1972, Enscore et al. 2002, Collinge et al. 2005, Brown et al. 2010).”
InfluentialThe trophic responses of two different rodent–vector–plague systems to climate change
Xu, L., Schmid, B. V., Liu, J., Si, X.-Y., Stenseth, N. C., & Zhang, Z. (2014) · Proceedings of the Royal Society B Biological Sciences · doi:10.1098/rspb.2014.1846 · Cited by 44 · see citing works
“Yet, although the relationship between climatic factors and the dynamics of disease has been studied frequently [11–15], this is seldom done within the context of a full trophic web, whether via bottom-up (e.”
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“In tropical regions the association with rainfall is mixed; plague intensity in southern China is positively associated with drought conditions during the preceding year and extremely wet or extremely dry conditions in the current year [34] and most human cases occur during the dry season in Vietnam [41,42,43].”
BackgroundDemographic and spatio-temporal variation in human plague at a persistent focus in Tanzania
Davis, S., Makundi, R. H., Machang’u, R. S., et al. (2006) · Acta Tropica · doi:10.1016/j.actatropica.2006.10.006 · Cited by 43 · see citing works
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“It is possible that flea survival is simply compromised during hot, dry weather [1,18,21,33].”
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“Key words: black-tailed prairie dog; Cynomys ludovicianus; disease ecology; generalized linear models; spatial autocorrelation; temporal autocorrelation; vector-borne disease; Yersinia pestis.”
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Gage, K. L. (2012) · Advances in experimental medicine and biology · doi:10.1007/978-1-4614-3561-7_11 · Cited by 38 · see citing works
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Effects of Temperature on Early-Phase Transmission of Yersina pestis by the Flea, Xenopsylla cheopis
Schotthoefer, A. M., Bearden, S. W., Vetter, S. M., Holmes, J. L., Montenieri, J. A., Graham, C. B., Woods, M. E., Eisen, R. J., & Gage, K. L. (2011) · Journal of Medical Entomology · doi:10.1603/me10155 · Cited by 31 · see citing works
“…were more frequent during warm, humid conditions, but when temperatures exceeded 27 C (80 F), epidemics would promptly decline, suggesting that hot weather inhibited transmission in some way (Rogers 1928, Davis 1953, Hirst 1953, Pollitzer 1954, Kartman and Prince 1956, Cavanaugh and Marshall 1972).”
BackgroundMacMillan, K., Monaghan, A. J., Apangu, T., Griffith, K., Mead, P. S., Acayo, S., Acidri, R., Moore, S. M., Mpanga, J. T., Enscore, R. E., et al. (2012) · American Journal of Tropical Medicine and Hygiene · doi:10.4269/ajtmh.2012.11-0569 · Cited by 31 · see citing works
“The increased moisture associated with rainfall also supports survival and reproduction of fleas.(15,23) The combined escalation in rodent and flea abundances is believed to enhance the likelihood of plague epizootics.”
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Snäll, T., Benestad, R. E., & Stenseth, N. C. (2008) · Global Change Biology · doi:10.1111/j.1365-2486.2008.01725.x · Cited by 30 · see citing works
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Plague in Egypt: Disease biology, history and contemporary analysis: A minireview
Lotfy, W. M. (2013) · Journal of Advanced Research · doi:10.1016/j.jare.2013.11.002 · Cited by 24 · see citing works
“In Vietnam, studies showed an increased plague incidence during the hot, dry season, when it followed a period of high seasonal rainfall [50,51].”
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“These same meteorological events markedly influence flea activity (Bacot and Martin 1924, Amin 1966, Olson 1969, Cavanaugh and Marshall 1972).”
InfluentialClimate-driven marmot-plague dynamics in Mongolia and China
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“A few studies in Vietnam and the USA have established statistically that climate has a strong influence on the epizootics, the stage of the plague cycle in which the disease is the most infectious [24-27].”
BackgroundResultThe Effect of Seasonal Weather Variation on the Dynamics of the Plague Disease
Ngeleja, R. C., Luboobi, L. S., & Nkansah-Gyekye, Y. (2017) · International Journal of Mathematics and Mathematical Sciences · doi:10.1155/2017/5058085 · Cited by 17 · see citing works
“[3] reported that, in areaswhere drains are absent, orwhere drainage is insufficient as a result of soil composition or impoundments of water, flooding unquestionably causes a drop in the flea population.”
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“An association between warm, moist climate and higher levels of flea vectors has also been discussed in the literature (Cavanaugh & Marshall, 1972; Davis, 1953).”
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“We subsequently dropped rainfall from the model and retained temperature as these were highly correlated (r = 0.51) and because temperature is known to influence flea growth and development (Cavanaugh and Marshall 1972; Kreppel et al., 2016; Ming ming et al., 2013).”
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- Authors
- CAVANAUGH, D. C., & MARSHALL, J. D.
- ORCID
- MARSHALL, JOHN D.
- Venue
- Journal of Wildlife Diseases
- Publisher
- Wildlife Disease Association
- Published
- 1972-01
- Volume
- 8
- Issue
- 1
- Pages
- 85-94
- ISSN
- 0090-3558 (ISSN-L)
- OpenAlex
- W1977039438
- Cited by
- 62
- References
- 0
- Citations by year
- 2025: 2 · 2024: 2 · 2023: 3 · 2020: 1 · 2019: 2 · 2017: 3 · 2015: 1 · 2014: 1 · 2013: 6 · 2012: 5
- FWCI
- 0.64
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Journal of Wildlife Diseases (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Yersinia bacterium, plague, ectoparasites research
- Health Sciences › Medicine › Public Health, Environmental and Occupational Health › Zoonotic diseases and public health
- Physical Sciences › Environmental Science › Ecology › Animal Ecology and Behavior Studies
- Keywords
- bubonic plague, seasonal prevalence, climate, Xenopsylla cheopis, flea-borne transmission, plague epidemics, temperature, relative humidity, vapor pressure deficit, Vietnam
- MeSH terms
- Animals, Climate, Disease Vectors, Siphonaptera, Humans, Humidity, Insect Vectors, Plague, Rodentia, Seasons, Temperature, Vietnam, Weather
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