How to mitigate COVID-19 transmission in densely populated areas globally

How to mitigate COVID-19 transmission in densely populated areas globally

Updated Dec. 3, 2020

Document purpose: High-density urban areas may face challenges implementing COVID-19 mitigation measures due to space limitations within and between households and limited water, sanitation, and hygiene (WASH) infrastructure. This document provides suggestions for community mitigation measures in densely populated, international, low-resource settings and describes implementation considerations associated with each measure. Community mitigation activities are actions that people and communities can take to prevent or reduce local COVID-19 transmission. This document describes measures that both individuals and organizations can take to support households in high-density urban areas.

Document audience: This document is intended for use by any person, institution, or organization preparing for or responding to community transmission in high-density urban settings and for those assisting those organizations (federal and local governments, CDC country offices, and others). It contains special considerations for low-resource, international settings.

Layered approach: Mitigation measures can be organized into three categories: personal controls, administrative controls, and engineering controls. These should be layered to reduce overall risk of COVID-19 transmission. In this document, personal controls are primarily limited to actions that individuals can take to prevent transmission within households, whereas administrative and engineering controls are actions that communities, organizations, and governments can take to prevent transmission between households

Personal controls: Individual behaviors to protect themselves and those around them.
Administrative controls: Processes and policies that keep people safe.
Engineering controls: Physical structures put in place to distance people from hazards.

Note on implementation: Below are suggestions for how to mitigate COVID-19 transmission in densely populated areas. Community members must be engaged in the process of planning and implementing any mitigation measures for them to be successful. Engaging local populations is important as you adapt measures to fit the local context. To do so, identify trusted stakeholders and community leaders to provide feedback on proposed mitigation measures before they are implemented. They know the local needs and conditions and are able to apply lessons learned from previous public health interventions in the community, which may complement proposed COVID-19 mitigation interventions. Additionally, they can assist with adapting mitigation measures to fit local laws and regulations. More information on how to effectively engage communities is herepdf iconexternal icon.

Document organization: This document provides an overview of four key mitigation practices: physical distancing, hand hygiene, cleaning and disinfection, and respiratory etiquette. This is followed by operational considerations in the following order:

Personal controls that individuals can take to prevent transmission within households, with additional considerations for individuals at increased risk of severe illness from COVID-19 (the elderly and people with conditions including lung or heart disease, obesity, diabetes, chronic kidney disease, liver disease, or other disease that compromises immunity),
Administrative and engineering controls to be taken by community members, organizations, and governments to prevent transmission between households and in public settings, and
Considerations (personal controls) for home-based care for a person with suspected or confirmed COVID-19.

Four key mitigation practices for individuals and households.

Physical distancing, hand hygiene, cleaning and disinfection, and respiratory etiquette are four of the main things people can do to prevent the spread of COVID-19. This section describes the main principles to follow for each one.
- Physical distancing: Maintain at least a 6 foot distance from individuals from outside the household and practice greetings without touching, such as waving, placing a hand over the heart, bowing, or nodding your head.
- Hand hygiene: Clean hands frequently. People should clean their hands after being in a public place, after blowing their nose, sneezing, or coughing, after using the toilet, and other key times.
Types of hand hygiene:
- Handwashing with soap and water. Soap and water are effective at removing germs from hands, including the virus that causes COVID-19. The cleanest water available (ideally from an improved sourceexternal icon)1 should be used for handwashing, and all types of soap (bar soap, liquid soap, and powder soap) are effective at removing coronaviruses from hands. Scrub hands with soap and water for at least 20 seconds and dry them completely by air or by using single-use hand towels or paper towels.
- Soapy water (a mix of water and either powdered or liquid soap) can be used. To prepare, mix enough soap with water in a bottle or handwashing station so that you can create a foam when rubbing hands together. You will also need a separate handwashing station of rinse water next to the soapy water station. As detailed above, use the cleanest water available for soapy water and rinse water. Detailed instructions for making soapy water can be found on page 25 of the Handwashing Compendium for Low Resource Settingspdf iconexternal icon.
  
  All handwashing stations should: 1) Allow users to wet and rinse their hands under a stream of running water; 2) Have soap or soapy water available; 3) Have a place to catch or adequately drain used water; 4) provide single-use hand towels or paper towels, whenever possible; and 5) provide a waste bin to collect paper towels, when applicable. Additionally, handwashing stations should be durable, easy to use for all users, including children, elderly, and people with disabilities.
Cleaning with alcohol-based hand rub. If hands are not visibly dirty, you can use hand rub containing at least 60% alcohol as an alternative to washing hands when soap and water are not available. To use, apply enough product to cover all surfaces of both hands and rub together until they feel dry, or for approximately 20 seconds. Young children may need supervision when using hand rub to prevent accidental drinking.
Cleaning and disinfection
- Clean and disinfect frequently touched surfaces at least once a day, and more often based on level of use. This includes door handles, toilet/latrine surfaces, tables, and chairs.
- Cleaning refers to the removing germs, dirt, and impurities from surfaces with soap or detergent. It does not kill germs, but by removing them, it lowers the risk of spreading infection. Some surfaces only need to be cleaned with soap and water, for example surfaces and objects that are not frequently touched should be cleaned and do not require additional disinfection. Additionally, disinfectants should typically not be applied on items used by children, especially any items that children might put in their mouths.
- Disinfecting uses chemicals, such as bleach (sodium hypochlorite), to kill germs on surfaces. This process does not necessarily clean dirty surfaces or remove germs, but by killing germs on a surface after cleaning, it can further lower the risk of spreading infection.
- Use a 0.1% solution made from liquid bleach and water for disinfection.
Cleaning and disinfection procedures:

Put on personal protective equipment (thick aprons and closed shoes) and wear reusable or disposable gloves to protect yourself against the disinfection or cleaning agents.
Clean with detergent or soap and water to remove dirt.
Mix 0.1% bleach solution using the procedures described above in a well-ventilated area.
Apply the 0.1% solution to the surface with a cloth. The surface should stay wet for at least 1 minute (contact time for the bleach to be effective). You may apply additional disinfectant to ensure it remains wet for 1 minute. After 1 minute has passed, rinse residue with clean water (this will also protect the surface or item from damage).
After cleaning and disinfection, remove personal protective equipment (PPE) to dispose of or launder. Single use gloves should be discarded after each cleaning. If reusable gloves are used, they should be dedicated for cleaning and disinfection of surfaces for COVID-19 and should not be used for other purposes. Consult the manufacturer’s instructions for cleaning and disinfection products. Clean hands immediately after gloves are removed using above instructions.

Cleaning and disinfecting should not take place near children or people with asthma. Additionally, store cleaning/disinfecting supplies in a locked, secured location, out of the reach of children and away from fire/flames.

Public Services and Health Committee