Half of the world’s population still does not have adequate access to safe drinking water, sanitation and hygiene (WASH) which could have prevented at least 1.4 million deaths and 74 million disability-adjusted life years in 2019, according to this latest report by the World Health Organization (WHO).

At present, South Asia is among the sub-regions where the spread of COVID-19 transmission is peaking. The intersection of the pandemic with the climate emergencies has created challenges that sub-region has not dealt with before and could magnify the negative impacts in some countries.

The United Nations (UN) and humanitarian partners in the Philippines launched the largest international humanitarian response plan in the country since Typhoon Haiyan in 2013.

The COVID‑19 crisis is affecting everyone, but women and girls are being differently impacted and could face disproportionate economic, health and social risks. These gender-differentiated socio-economic risks must be recognized for an effective COVID-19 response and recovery.

This scientific brief provides an overview of the modes of transmission of SARS-CoV-2, what is known about when infected people transmit the virus, and the implications for infection prevention and control precautions within and outside health facilities. This scientific brief is not a systematic review.