Contact tracing for covid-19 in low- and middle-income countries

In the absence of an effective vaccine or treatment, the key measures to control the covid-19 pandemic are testing and isolating cases, and then tracing and quarantining potential contacts. But contact tracing must be context specific, because in low-and middle-income countries, identifying the cases and tracing their contacts may be impaired by poor access to formal healthcare systems, inadequate specialised diagnostic facilities, and limited numbers of healthcare workers. 

The Government of Bangladesh has extended its testing capability; there are now 43 diagnostic laboratories across the country and the number of tests performed is increasing daily. However, given its limited resources, like any other low- and middle-income country, it is overly ambitious to expect that Bangladesh can rapidly expand its testing capacity. 

On the other hand, Bangladesh has the capacity to scale up its contact tracing strategies. 

Contact tracing in Bangladesh is mainly monitored centrally by the Institute of Epidemiology, Disease Control and Research (IEDCR) of the Government of Bangladesh. Within the capital city, Dhaka, contact tracing is done by health professionals from IEDCR. Outside the capital, contact tracing is done by rapid response teams at district and sub-district levels. 

In a densely populated country like Bangladesh, with 1,116 people living per square kilometre, and rapidly increasing community transmission of covid-19, this centralised approach of contact tracing will be overwhelmed. Sixty per cent of the population also lives in rural areas, where contract tracing by centralised staff will be further challenging by lack of familiarly of the village structure and community mistrust of the “unknown” which may result in concealing exposure information.

Bangladesh has a tightly knit social network, which means community members know and interact with each other on a regular basis, particularly in rural areas. Within the rural areas, there are community-based health services (both government and non-government) provided by an extensive cadre of 185,000 community health workers (CHWs). These CHWs are accepted by the communities because they are selected from the communities and answerable to the community members for their activities. The CHWs are trained to treat common medical conditions and in health promotion, and refer patients to preventive and curative services as appropriate. 

Bangladesh is considered a role model in successfully implementing national health programmes though CHWs, including family planning, tuberculosis control and integrated management of neonatal and childhood illness. This unique extensive network of frontline health workers can be successfully leveraged for contact tracing in rural areas of Bangladesh. When a covid-19 patient is confirmed, the CHW from the area where the patient lives can be notified either by the IEDCR or local health administrative unit. The CHW can contact the patient to collect a potential list of contacts, get in touch with these contacts and provide them with instructions on how to quarantine themselves and monitor contacts for the next 14 days to check if they develop symptoms. 

For urban areas, where the population is much more dispersed, contact tracing through CHWs might not be a feasible option. The IEDCR in collaboration with International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b) have ongoing surveillance for different communicable diseases in 16 tertiary hospitals in seven of the eight divisions of the country, including three within the Dhaka division where more than 80% of the covid-19 cases are concentrated. All the surveillance hospitals are staffed with dedicated field staff who are trained in health data collection and can be leveraged for tracing of contacts within urban areas Additionally, the country has approximately 48,000 students enrolled in Bachelor of Medicine and Bachelor of Surgery programmes and 13,000 enrolled on the BSc nursing programme who can also be mobilised as contact tracers in urban areas. Contact tracing could be included as part of these programmes of study to build health workers’ capacity for dealing with any future health crises. 

More than 85% of households in Bangladesh have access to mobile phones, and these can also be used to collect data for contact tracing. Data can be uploaded to IEDCR database through community clinics, emailed or shared directly by the mobile device. Financial incentive for contact tracers may aid data collection.

The covid-19 pandemic has created a global crisis of a magnitude that we have never had to deal with in our lifetime. The unique nature of the crisis underscores the need for creative and rapid actions, focusing first and foremost on country-specific public-health infrastructure and the science of containment and mitigation strategies. 

Nusrat Homaira is a respiratory epidemiologist and senior lecturer with University of New South Wales, Sydney Australia. 

Md Saiful Islam is an infection prevention and control scientist and a PhD researcher at University of New South Wales, Sydney Australia

Zakiul Hassan is an emerging infectious disease researcher at International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b)

Najmul Haider is an epidemiologist and post-doctoral researcher at Royal Veterinary College, University of London, United Kingdom 

Syed Moinuddin Satter is an infectious disease epidemiologist and assistant scientist at the International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b)

Competing interests: None declared