Preliminary observations on factors responsible for long persistence and continued outbreaks of plague in Lushoto district, Tanzania

Identification of Risk Factors for Plague in the West Nile Region of Uganda

“…48 As suggested, sleeping on floors may put persons at greater risk of exposure to fleas, thus increasing plague risk. 43 Similar to an earlier study in the West Nile Region, 36 our study found that sleeping substrate could indirectly affect contact rates between humans and fleas. Specifically, we showed that persons in case villages were more likely to sleep on reed or straw mats compared with their counterparts in control villages.…”

“…It is unclear if this relates simply to this substrate putting persons in closer contact with the ground than other substrates, or if these mats may be more likely than alternatives (e.g., foam or other stuffed mattresses) to harbor fleas because the organic content or dust in the mats could provide a suitable substrate for breeding of fleas. 22,43 Although not mutually exclusive, the latter suggestion was supported by our observation that X. cheopis and C. felis were more abundant in households that reported sleeping on reed or straw bedding than in those that did not sleep on this material.…”

“…33,38,41,42 The finding of similar host abundance inside of huts regardless of plague history could suggest that abundance is generally high enough within homes to pose a risk to inhabitants and that human behavior may significantly impact the risk of plague infection in this setting. 43 In general, poor housing construction or maintenance, storage of food inside homes, and availability of harborage for rodents (e.g., thatch roofing, dense vegetation, or garbage around homes) promote rodent survival in the home environment. [43][44][45] Thus, in an effort to reduce contact between rodents, their fleas, and humans, plague prevention strategies often focus on reducing food and harborage for rodents in this setting.…”

“…43 In general, poor housing construction or maintenance, storage of food inside homes, and availability of harborage for rodents (e.g., thatch roofing, dense vegetation, or garbage around homes) promote rodent survival in the home environment. [43][44][45] Thus, in an effort to reduce contact between rodents, their fleas, and humans, plague prevention strategies often focus on reducing food and harborage for rodents in this setting. 4,8,9,35 Providing support for this recommendation, our study showed that homesteads in case villages more frequently reported storing food, and garbage (largely food scraps) inside huts where persons sleep, or cooking inside huts where persons sleep.…”

Predicting Potential Risk Areas of Human Plague for the Western Usambara Mountains, Lushoto District, Tanzania

“…5 Studies of plague ecology and epidemiology in Africa have generally been focused at microscales, examining hostvector-parasite systems and human social-activity patterns within single foci. [6][7][8] These studies have nonetheless been unable to elucidate environmental factors shaping plague distributions at regional scales; a few studies have attempted to link plague distribution and the distributions of plague hosts and vectors with environmental factors, [9][10][11][12][13] but only two of these studies have focused on Africa. In a previous study, we developed ecological-niche models for Africa, exploring environmental conditions appropriate for plague occurrence and finding a broad potential distributional area of plague across Africa.…”