Seroprevalence of SARS-CoV-2 and select vaccine preventable diseases in Timor-Leste


Seroprevalence studies provide estimates of antibody levels against infectious diseases and are considered the gold standard for measuring population immunity due to past infection or through vaccination. Currently, our understanding of the epidemiology of COVID-19 in Timor-Leste has been based on the identification of cases that presented for testing or were symptomatic. 


This project aims to obtain seroprevalence estimates of SARS-CoV-2 and select vaccine preventable diseases, including measles, rubella, hepatitis B and dengue, to understand the extent of exposure to these viruses in the broader Timor-Leste community. The study findings will guide public health policy to control and mitigate the ongoing impacts of COVID-19 as well as other vaccine preventable diseases. 


In partnership with the Timor-Leste Ministry of Health, the study team will conduct a series of population representative cross-sectional surveys through randomly selected households from every municipality. More than 5,000 people will be invited to participate. The work involves testing blood (serum or plasma) samples for antibodies.


Various locations in Timor-Leste


  • Findings from this project will provide essential information on the extent and nature of infection and possible immunity to SARS-CoV-2 and other vaccine preventable diseases in Timor-Leste. This information will help strengthen Timor-Leste’s ability to efficiently prevent future outbreaks of these diseases by enabling targeted vaccination drives in non-immune populations.
  • Seroprevalence studies are an important component of disease surveillance with the findings used to inform public health policy, vaccination strategies and other models to predict future disease spread and understand needs of the health service to control and subsequently, eliminate these diseases in Timor-Leste. 
  • As Timor-Leste has experienced significant community transmission of SARS-CoV-2, determining what proportion of the population has evidence of antibodies against COVID-19, from either infection or vaccination, will help with planning for the ongoing public health response and to encourage high vaccine uptake.  

Project team

Principal investigator: Dr Nelson Martins (Menzies School of Health Research)

Study team: Dr Josh Francis and the Menzies School of Health Research team, Dr Sarah Sheridan (NCIRS)


Menzies School of Health Research: ARIA-RISE project - publications and news items 


For any enquiries, please email the ARIA secretariat