Inter‐Group Social Behavior, Contact Patterns and Risk for Pathogen Transmission in Cape Buffalo Populations

Cross-species transmission of pathogens is intimately linked to human and environmental health. With limited healthcare and challenging living conditions, people living in poverty may be particularly susceptible to endemic and emerging diseases. Similarly, wildlife is impacted by human influences, including pathogen sharing, especially for species in close contact with people and domesticated animals. Here we investigate human and animal contacts and human health in a community living around the Bwindi Impenetrable National Park (BINP), Uganda. We used contact and health survey data to identify opportunities for cross-species pathogen transmission, focusing mostly on people and the endangered mountain gorilla. We conducted a survey with background questions and self-reported diaries to investigate 100 participants’ health, such as symptoms and behaviours, and contact patterns, including direct contacts and sightings over a week. Contacts were revealed through networks, including humans, domestic, peri-domestic, and wild animal groups for 1) contacts seen in the week of background questionnaire completion, and 2) contacts seen during the diary week. Participants frequently felt unwell during the study, reporting from one to 10 disease symptoms at different intensity levels, with severe symptoms comprising 6.4% of the diary records and tiredness and headaches the most common symptoms. After human-human contacts, direct contact with livestock and peri-domestic animals were the most common. The contact networks were moderately connected and revealed a preference in contacts within the same taxon and within their taxa groups. Sightings of wildlife were much more common than touching. However, despite contact with wildlife being the rarest of all contact types, one direct contact with a gorilla with a timeline including concerning participant health symptoms was reported. When considering all interaction types, gorillas mostly exhibited intra-species contact, but were found to interact with five other species, including people and domestic animals. Our findings reveal a local human population with recurrent symptoms of illness in a location with intense exposure to factors that can increase pathogen transmission, such as direct contact with domestic and wild animals and proximity among animal species. Despite significant biases and study limitations, the information generated here can guide future studies, such as models for disease spread and One Health interventions.

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Escherichia coli Population Structure and Antibiotic Resistance at a Buffalo/Cattle Interface in Southern Africa

Applied and Environmental Microbiology ◽

10.1128/aem.03771-15 ◽

2015 ◽

Vol 82 (5) ◽

pp. 1459-1467 ◽

Cited By ~ 14

Author(s):

Mathilde Mercat ◽

Olivier Clermont ◽

Méril Massot ◽

Etienne Ruppe ◽

Michel de Garine-Wichatitsky ◽

...

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Genetic Material ◽

Pathogen Transmission ◽

African Buffalo ◽

Content Type ◽

E Coli ◽

Natural Interface ◽

Contact Patterns

ABSTRACTAt a human/livestock/wildlife interface,Escherichia colipopulations were used to assess the risk of bacterial and antibiotic resistance dissemination between hosts. We used phenotypic and genotypic characterization techniques to describe the structure and the level of antibiotic resistance ofE. colicommensal populations and the resistantEnterobacteriaceaecarriage of sympatric African buffalo (Syncerus caffer caffer) and cattle populations characterized by their contact patterns in the southern part of Hwange ecosystem in Zimbabwe. Our results (i) confirmed our assumption that buffalo and cattle share similar phylogroup profiles, dominated by B1 (44.5%) and E (29.0%) phylogroups, with some variability in A phylogroup presence (from 1.9 to 12%); (ii) identified a significant gradient of antibiotic resistance from isolated buffalo to buffalo in contact with cattle and cattle populations expressed as the Murray score amongEnterobacteriaceae(0.146, 0.258, and 0.340, respectively) and as the presence of tetracycline-, trimethoprim-, and amoxicillin-resistant subdominantE. colistrains (0, 5.7, and 38%, respectively); (iii) evidenced the dissemination of tetracycline, trimethoprim, and amoxicillin resistance genes (tet,dfrA, andblaTEM-1) in 26 isolated subdominantE. colistrains between nearby buffalo and cattle populations, that led us (iv) to hypothesize the role of the human/animal interface in the dissemination of genetic material from human to cattle and toward wildlife. The study of antibiotic resistance dissemination in multihost systems and at anthropized/natural interface is necessary to better understand and mitigate its multiple threats. These results also contribute to attempts aiming at usingE. colias a tool for the identification of pathogen transmission pathway in multihost systems.

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The impact of COVID-19 control measures on social contacts and transmission in Kenyan informal settlements

BMC Medicine ◽

10.1186/s12916-020-01779-4 ◽

2020 ◽

Vol 18 (1) ◽

Cited By ~ 3

Author(s):

Matthew Quaife ◽

◽

Kevin van Zandvoort ◽

Amy Gimma ◽

Kashvi Shah ◽

...

Keyword(s):

Food Security ◽

Social Contact ◽

Informal Settlements ◽

Pathogen Transmission ◽

Control Measures ◽

Respiratory Pathogen ◽

African Countries ◽

Contact Patterns ◽

And Control ◽

The Impact

Abstract Background Many low- and middle-income countries have implemented control measures against coronavirus disease 2019 (COVID-19). However, it is not clear to what extent these measures explain the low numbers of recorded COVID-19 cases and deaths in Africa. One of the main aims of control measures is to reduce respiratory pathogen transmission through direct contact with others. In this study, we collect contact data from residents of informal settlements around Nairobi, Kenya, to assess if control measures have changed contact patterns, and estimate the impact of changes on the basic reproduction number (R0). Methods We conducted a social contact survey with 213 residents of five informal settlements around Nairobi in early May 2020, 4 weeks after the Kenyan government introduced enhanced physical distancing measures and a curfew between 7 pm and 5 am. Respondents were asked to report all direct physical and non-physical contacts made the previous day, alongside a questionnaire asking about the social and economic impact of COVID-19 and control measures. We examined contact patterns by demographic factors, including socioeconomic status. We described the impact of COVID-19 and control measures on income and food security. We compared contact patterns during control measures to patterns from non-pandemic periods to estimate the change in R0. Results We estimate that control measures reduced physical contacts by 62% and non-physical contacts by either 63% or 67%, depending on the pre-COVID-19 comparison matrix used. Masks were worn by at least one person in 92% of contacts. Respondents in the poorest socioeconomic quintile reported 1.5 times more contacts than those in the richest. Eighty-six percent of respondents reported a total or partial loss of income due to COVID-19, and 74% reported eating less or skipping meals due to having too little money for food. Conclusion COVID-19 control measures have had a large impact on direct contacts and therefore transmission, but have also caused considerable economic and food insecurity. Reductions in R0 are consistent with the comparatively low epidemic growth in Kenya and other sub-Saharan African countries that implemented similar, early control measures. However, negative and inequitable impacts on economic and food security may mean control measures are not sustainable in the longer term.

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Risk factors for the evolutionary emergence of pathogens

Journal of The Royal Society Interface ◽

10.1098/rsif.2010.0123 ◽

2010 ◽

Vol 7 (51) ◽

pp. 1455-1474 ◽

Cited By ~ 28

Author(s):

H. K. Alexander ◽

T. Day

Keyword(s):

Risk Factors ◽

Empirical Studies ◽

Point Mutations ◽

Host Population ◽

Pathogen Transmission ◽

New Host ◽

Contact Patterns ◽

Pathogen Fitness ◽

Contact Distribution ◽

The Impact

Recent outbreaks of novel infectious diseases (e.g. SARS, influenza H1N1) have highlighted the threat of cross-species pathogen transmission. When first introduced to a population, a pathogen is often poorly adapted to its new host and must evolve in order to escape extinction. Theoretical arguments and empirical studies have suggested various factors to explain why some pathogens emerge and others do not, including host contact structure, pathogen adaptive pathways and mutation rates. Using a multi-type branching process, we model the spread of an introduced pathogen evolving through several strains. Extending previous models, we use a network-based approach to separate host contact patterns from pathogen transmissibility. We also allow for arbitrary adaptive pathways. These generalizations lead to novel predictions regarding the impact of hypothesized risk factors. Pathogen fitness depends on the host population in which it circulates, and the ‘riskiest’ contact distribution and adaptive pathway depend on initial transmissibility. Emergence probability is sensitive to mutation probabilities and number of adaptive steps required, with the possibility of large adaptive steps (e.g. simultaneous point mutations or recombination) having a dramatic effect. In most situations, increasing overall mutation probability increases the risk of emergence; however, notable exceptions arise when deleterious mutations are available.

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Nationally Representative Social Contact Patterns in the United States, August 2020-April 2021

10.1101/2021.09.22.21263904 ◽

2021 ◽

Author(s):

Kristin N. Nelson ◽

Aaron J Siegler ◽

Patrick S Sullivan ◽

Heather Bradley ◽

Eric Hall ◽

...

Keyword(s):

Social Behavior ◽

Food Service ◽

Social Contact ◽

The United States ◽

Mechanistic Models ◽

Demographic Groups ◽

Contact Rates ◽

Contact Patterns ◽

Nationally Representative ◽

Vaccine Availability

AbstractThe response to the COVID-19 pandemic in the U.S prompted abrupt and dramatic changes to social contact patterns. Monitoring changing social behavior is essential to provide reliable input data for mechanistic models of infectious disease, which have been increasingly used to support public health policy to mitigate the impacts of the pandemic. While some studies have reported on changing contact patterns throughout the pandemic., few have reported on differences in contact patterns among key demographic groups and none have reported nationally representative estimates. We conducted a national probability survey of US households and collected information on social contact patterns during two time periods: August-December 2020 (before widespread vaccine availability) and March-April 2021 (during national vaccine rollout). Overall, contact rates in Spring 2021 were similar to those in Fall 2020, with most contacts reported at work. Persons identifying as non-White, non-Black, non-Asian, and non-Hispanic reported high numbers of contacts relative to other racial and ethnic groups. Contact rates were highest in those reporting occupations in retail, hospitality and food service, and transportation. Those testing positive for SARS-CoV-2 antibodies reported a higher number of daily contacts than those who were seronegative. Our findings provide evidence for differences in social behavior among demographic groups, highlighting the profound disparities that have become the hallmark of the COVID-19 pandemic.

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