Faculté de médecine Faculté de médecine

[988] Infectious Diseases and Mathematical Modelling

The division consists of mathematicians, computer scientists, physicists, statisticians, biologists, physicians, and social scientists. They collaborate closely with experts from a variety of fields, such as Ministries of Health, and with international organisations like the WHO, UNITAID and the World Bank. The division takes an interdisciplinary approach and combines machine learning, mathematical modelling (including cost-effectiveness analyses), analyses of cohort data, systematic reviews, text mining, and qualitative research techniques. The division focuses on HIV, influenza and hepatitis, both in Switzerland and abroad. But it is also interested in expanding its work to other infectious diseases, and in studying the interaction between communicable and non-communicable diseases.

The GRAPH Network

The Global Research and Analyses for Public Health (GRAPH) Network conducts research, builds epidemiological tools and develops training materials to enhance disease surveillance and data science for public health across the globe.

COVID-19

  • Development of a sentinel surveillance system of Covid-19 patients in collaboration with the Swiss Federal Office of Public Health and a number of Swiss hospitals: https://www.unige.ch/medecine/hospital-covid/
  • Development of  a mathematical model to simulate the course of the Covid-19 epidemic in Switzerland:https://gitlab.com/igh-idmm-public/covid-19/modelling_jestill)
  • Collaboration with Citizen Cyberlab at Unige and the Citizen Science Center of ETH/UZH on an automatic classification system to rapidly review and classify the fast growing body of Covid-19 scientific literature
  • Support several African countries with their national response

Modelling HIV and HCV Epidemics

We have developed several mathematical simulation models for HIV-infected adults and children, as well as for tuberculosis and hepatitis C. One of our HIV models showed that tracing patients lost to follow-up prevents only a small number of HIV transmissions. In another project, we identified factors that may explain the typical age structure observed among diagnosed tuberculosis patients in Cape Town. To parameterise the models, we analyse primary data and conduct systematic reviews of published literature. We have developed a general version of a disease progression model that can be used for any type of disease; it is available online as an R package. We developed or applied simulation models in many of our other projects.

HIV in Malawi

In Malawi, we evaluated the prevention-of-mother-to-child-transmission program, “Option B+” by combining quantitative and qualitative analyses techniques. In that study, we found that both HIV testing frequency and loss to follow-up varied substantially across sites. When we mapped the data, we realised that loss to follow-up rates clustered spatially. We decided to explore this spatial clustering by analysing data from qualitative focus groups and in-depth interviews of patients and health care workers.

In a follow-up project, we will extend the findings of this study to explore the spatial variability of HIV in Malawi and, wore widely, in sub-Saharan Africa. For this project, we will use state-of-the-art statistical analyses, review qualitative literature on socio-behavioural factors of HIV in Malawi, and develop a spatial simulation model. Since we work closely with local NGOs and the Ministry of Health, our findings will help others to develop and implement locally acceptable interventions.

Other HIV-related collaborations

For the past 10 years, we have led and contributed to many analyses on HIV therapy outcomes in HIV-infected adults and children in sub-Saharan Africa (IeDEA collaboration, www.iedea.org). One of our PhD students is, for example, now working on an analysis of therapy failure and third-line therapy in Zimbabwe. We continue to be an active partner in this worldwide network of HIV cohort studies.

With the groups of Prof David Wilson (Burnet Institute Australia), the World Bank UNAIDS, and other partners, we constitute the “Optima group” (www.optimamodel.com). Optima is an allocative efficiency analysis tool that can be used to inform public health investment choices, and can also be utilised for academic research. The Optima approach involves, for example, assessing the burden of disease over time, defining strategic objectives under logistic, ethical or and/or political constraints; and, determining optimal resources allocation for achieving objectives. Optima is available for HIV, tuberculosis, nutrition, and hepatitis C. Other modules are in development.

Hepatitis C in Switzerland

We have led several epidemiological analyses within the Swiss Hepatitis C Cohort Study SCCS (www.swisshcv.org). We have focused on access to care and therapy outcomes. We also had a mandate from the Swiss Federal Office of Public Health to conduct a situation analysis of hepatitis B and C in Switzerland. We have worked on several simulation models that assess the effect of difference screening and therapy interventions for hepatitis C-infected patients in Switzerland.

Influenza in Switzerland

In collaboration with the Federal Office of Public Health, the virology and infection control departments at the University hospital of Geneva, and other hospitals in Switzerland we are implementing a pilot study for hospitalised influenza cases in Switzerland. It is likely that influenza cases in hospitals differ from community-based cases regarding patient characteristics and potentially also patterns of circulating strains. With a hospital-based system, we will be able to study the evolution of the epidemic and better understand influenza in hospitalised patients who are most at risk.

Integrated e-Diagnostic Approach Project

In the frame of a collaboration with the Terre des Hommes foundation (www.tdh.ch), the Cloudera foundation (www.clouderafoundation.org), and the Health Informatics for Innovation, Integration, Implementation and Impact Laboratory (HI5lab), led by Prof. Antoine Geissbuhler and hosted at the Faculty of Medicine of the University of Geneva, we contribute to the IeDA (Integrated e-Diagnostic Approach) project (www.IeDA-project.org). The aim of IeDA is to support health care workers in primary health care facilities in West Africa, with mHealth tools and methodologies, for diagnosing and treating children under 5 years-old, based on the IMCI Integrated Management of Childhood Illness (IMCI) WHO protocol and according to national protocols. We are involved in the development and implementation of new data management and visualization tools, digital job-aids solutions, and epidemiological analyses, based on medical consultation data collected in the frame of IeDA in Burkina Faso, including artificial intelligence and machine learning approaches. Such technological resources should enable the Ministry of Health and other partners to increase the quality of care provided in the country, providing invaluable information for planning potential targeted interventions.