What specific considerations apply for heatwaves in urban informal settlements during the COVID-19 pandemic?


Updated: 17 May 2020


The indoor heat exposure experienced by residents of urban informal settlements can be dangerously high. Recorded temperatures from urban/metropolitan weather stations likely underestimate actual indoor conditions. Informal settlements can exist in low-income countries as much as high-income countries.


Staying indoors during a heatwave for inhabitants of informal settlements will not be possible, especially during the hottest times of the day, regardless of physical distancing mandates that may be in place due to COVID-19. Additional measures therefore need to be introduced to reduce the spread of COVID-19, while allowing people to leave their homes to seek respite from the heat. Such provisions can include the frequent disinfection of high-frequency touch-points such as public drinking-water taps, or the distribution of face masks.


Access to water is especially crucial during a heatwave. City officials and COVID-19 planning teams should consider increasing the number of standpipes where possible. Other provisions, such as water tankers or temporary water access points, may increase the risk of transmitting COVID-19 in the community (and if used should ensure 0.5mg/Litre free residual chlorine levels). It is therefore critical that all shared water, sanitation and hygiene facilities are cleaned and disinfected frequently and thoroughly. Water contamination in informal settlements is often widespread, and access to clean water is essential to avoid other waterborne diseases on top of COVID-19. Informal settlement-based organizations and associations are important partners to mobilize in this activity. City officials can hire and train residents to oversee the disinfection process.


The residents of informal settlements are not a homogeneous group and the effects of heatwaves and COVID-19 are unevenly distributed across households and neighbourhoods. The capacity of households within informal settlements to respond to increased heat while remaining safe during the COVID-19 pandemic is not equal.


People will take calculated risks to ensure they can continue to meet their basic needs and access essential services (particularly food and water). Lockdowns and/or physical distancing measures will also amplify existing forms of social and economic inequality, which in turn may amplify vulnerability to the combined risks of extreme heat and COVID-19.

What can be done?

  • Ensure frequent cleaning and disinfection of shared water, sanitation and hygiene facilities. Water access is especially crucial during hot weather.
  • Establish mobile water stations for hand washing and distribute drinking water in places where there is limited or no piped water service.
  • Provide (cloth) face masks for everyone and teach people how to put them on, remove them and clean them safely.
  • Incorporate existing social networks into solutions and approaches.
  • Collaborate with community leaders and representatives of grass root organizations and groups to: identify high-risk groups, raise awareness/disseminate information, develop support programmes for the most vulnerable, identify appropriate ways of targeting, and develop and disperse appropriate low-cost heat management techniques and technologies.
  • Provide transparent information on infection rates and fatalities to keep people fully informed.
  • Remove threats of eviction or loss of tenure and provide food aid where people are unable to meet basic needs.
  • Continue to support heat health management initiatives whilst increasing capacity for local/urban authorities. The combined effects of heatwaves and COVID-19 on already overstretched healthcare systems will create unprecedented challenges for public health institutions, local authorities and national governments.


The health risks of hot weather are amplified in informal settlements, due to housing materials, dense concentration of living space, limited access to services, and other socio-economic factors. A 2015/2016 study of heat risks in Nairobi’s informal settlements documented that temperatures routinely exceed the central monitoring station by several degrees. A variation that is consistent with increased morbidity and mortality demonstrated in an earlier study in the same city. In Johannesburg, South Africa houses in informal settlements routinely experience indoor temperatures between 4 and 5°C warmer than outdoor temperatures. Informal settlements in Ahmedabad, India are routinely 2 to 3°C hotter than surrounding areas.