Effect of cotton face-masks and other behavioural and health-related risk factors on COVID-19 incidence and severity: Pragmatic cluster-randomized trial and nested observational study in Ranga Reddy district, Telangana

Implementing organizations / Contacts:

Dr Bharati Kulkarni, Scientist F (Senior Grade Deputy Director), Clinical Division. National Institute of Nutrition, Jamai Osmania, Tarnaka, Hyderabad.

Prof. Sanjay Kinra, Professor, Head of Department, Department of Non-communicable Disease Epidemiology, London School of Hygiene and Tropical Medicine/Andhra Pradesh Children and Parents’ Study (APCAPS)

Mr. S. KIRAN KUMAR, Managing Trustee, Synergy India Foundation, DSS Bhavan, Masab Tank, Hyderabad.

Aims and Objectives

Our aim is to generate robust evidence to inform national policy decisions on the use of masks and other urgent public health questions in the current COVID-19 epidemic. Our study has three

Primary Objectives:

1) Conduct a pragmatic cluster-randomized trial in 60 villages to assess the effectiveness of distributing cotton facemasks to all village residents on the incidence of COVID-19 in the villages.

2) Conduct a nested individual-level observational study to assess the health, behavioural and socio-demographic predictors of COVID-19 incidence and severity in a well-characterized cohort of ~10,000 village residents under active follow-up.

3) Use the findings from objectives 1 and 2 as inputs to conduct robust modelling studies of the possible trajectory of the COVID-19 epidemic under different public health intervention scenarios and estimate the cost-effectiveness of these various scenarios.


Primary outcome for the trial will be village-level incidence of COVID-19. Village leaders (Gram Panchayat) and health workers (ANMs, ASHAs) will be contacted by telephone on a weekly basis for reports of new suspected cases, new confirmed cases, any adverse events due to the face-masks, and process outcomes (e.g. intervention delivery, mask-wearing behavior). COVID-19 case information will be triangulated with other administrative data sources. Outcomes will be assessed continuously for up to 6 months and analyzed on a monthly basis for effectiveness and adverse events.

Secondary outcomes will include seroprevalence of SARS-CoV-2 antibodies measured in ~10,000 APCAPS cohort participants at the end of 6 months. These assays will be conducted on the blood samples already planned to be collected as part of the multi-morbidity study, using Roche Elecsys Anti-SARS-CoV-2 serology assay or similar validated method, in collaboration with ICMR laboratories.6 In the same samples, we will also measure antibodies against other common infections (e.g. malaria, chikungunya) that have been hypothesized to play a role in COVID-19. Other individual-level outcomes captured during the multi-morbidity survey will include symptoms of COVID-19, detailed clinical outcomes of severe cases (such as length of hospitalization, oxygen and ventilator requirements), occurrence of other common respiratory and diarrheal diseases (as face-mask use/hygiene may have beneficial effects on these as well), and deaths from COVID-19 and other causes in the household. Informed consent will be sought from participants to answer these additional questions and do the additional antibody assays. For the cost-effectiveness analyses, data on healthcare costs associated with treatment of COVID-19 will be collected from a sample of hospitals in the APCAPS area, as well as from government sources.

Study villages

Below is a list of villages proposed to participate – these include the 27 APCAPS study villages (marked by as *) plus neighboring villages covered by the same ANMs (color shading denotes villages covered by the same ANM). Subject to change.

1Madhapur31Kandukur and x road*
2Begumpet thanda32Makanu md nagar
5Gummadivalli thanda35Gudur*
9Kothval Cheruvu thanda39Narepally
10Nagalgone thanda40Jandamarri thanda
11Sheriguda*41Makthakancha thanda
17Gangaram 47Aakulamailram*
SDGs covered under project:

Selection of Self-Help Women Groups who have expertise in tailoring and training them on the manufacturing masks with required specifications, would cover up major SDGs and also would support them economically during this period.


Face-mask requirement

Approximate population size of the 60 villages proposed to participate in the study is ~120,000. Half of the villages, containing a population of ~60,000, will receive the facemasks. Assuming 5-10% of village population are infants and young children or otherwise unable to wear the facemasks, and 2 facemasks per person, total number of masks required will be ~110,000.

Face-mask Specifications

1. Preferably 3 layered with cotton on either side.

2. A combination of fabric with a tight weave like cotton and one that can hold a static charge are effective as they provide a double barrier for entry of particles both mechanical and electrostatic.

3. Cotton fabric with a thread count of 600/inch is shown to be effective in a recent research article.

4. When in doubt about the quality, we can hold the fabric to the light and check if you can see the individual fibers in it. If seen it is not effective.





National lock-down in India cannot be sustained. Interventions to reduce transmission of COVID-19 whilst maintaining crucial economic activity in society are urgently needed. This project will provide the first trial evidence on whether local-produced cotton facemasks could help mitigate the COVID-19 epidemic, and robust observational evidence on the potential impact of other hygiene and physical distancing practices.

Let us join hands to build a safer and healthier society.