Notice: There’s now a more moderen Novel Coronavirus (COVID-19) Situation Report 74.
International Stage: Very Excessive
Western Pacific Area
Japanese Mediterranean Area
Areas of the Americas
Because the COVID-19 outbreak continues to evolve, we’re studying extra about this new virus every single day. Right here we summarize what has been reported about transmission of the COVID-19 virus, and supply a short overview of obtainable proof on transmission from symptomatic, pre-symptomatic and asymptomatic individuals contaminated with COVID-19.
By means of definition, a symptomatic COVID-19 case is a case who has developed indicators and signs appropriate with COVID-19 virus an infection. Symptomatic transmission refers to transmission from an individual whereas they’re experiencing signs.
Information from printed epidemiology and virologic research present proof that COVID-19 is primarily transmitted from symptomatic individuals to others who’re in shut contact by respiratory droplets, by direct contact with contaminated individuals, or by contact with contaminated objects and surfaces.1-7 That is supported by detailed experiences shared by technical companions through WHO world skilled networks, and stories and shows by Ministries of Well being.
Information from scientific and virologic research which have collected repeated organic samples from confirmed sufferers present proof that shedding of the COVID-19 virus is highest in higher respiratory tract (nostril and throat) early in the midst of the illness.8-11 That’s, throughout the first 3 days from onset of signs.10-11 Preliminary knowledge suggests that folks could also be extra contagious across the time of symptom onset as in comparison with in a while within the illness.
The incubation interval for COVID-19, which is the time between publicity to the virus(changing into contaminated) and symptom onset, is on common 5-6 days, nonetheless could be as much as 14 days. Throughout this era, also called the “pre-symptomatic” interval, some contaminated individuals could be contagious. Subsequently, transmission from a pre-symptomatic case can happen earlier than symptom onset.
In a small variety of case stories and research, pre-symptomatic transmission has been documented by contact tracing efforts and enhanced investigation of clusters of confirmed instances.12-17 That is supported by knowledge suggesting that some individuals can check constructive for COVID-19 from 1-3 days earlier than they develop signs.6,16 Thus, it’s doable that folks contaminated with COVID-19 might transmit the virus earlier than important signs develop. You will need to acknowledge that pre-symptomatic transmission nonetheless requires the virus to be unfold through infectious droplets or by touching contaminated surfaces.
An asymptomatic laboratory-confirmed case is an individual contaminated with COVID-19 who doesn’t develop signs. Asymptomatic transmission refers to transmission of the virus from an individual, who doesn’t develop signs.
There are few stories of laboratory-confirmed instances who’re actually asymptomatic, and thus far, there was no documented asymptomatic transmission. This doesn’t exclude the chance that it might happen. Asymptomatic instances have been reported as a part of contact tracing efforts in some nations.
WHO commonly displays all rising proof about this vital subject and can present an replace as extra data turns into out there.
In case you are not in an space the place COVID-19 is spreading or haven’t traveled from an space the place COVID-19 is spreading or haven’t been in touch with an contaminated affected person, your threat of an infection is low. It’s comprehensible that you could be really feel anxious concerning the outbreak. Get the info from dependable sources that can assist you precisely decide your dangers so that you could take cheap precautions (see Frequently Asked Questions). Search steering from WHO, your healthcare supplier, your nationwide public well being authority or your employer for correct data on COVID-19 and whether or not COVID-19 is circulating the place you reside. You will need to learn of the scenario and take acceptable measures to guard your self and your loved ones (see Protection measures for everyone).
In case you are in an space the place there are instances of COVID-19 you want to take the chance of an infection severely. Observe the recommendation of WHO and steering issued by nationwide and native well being authorities. For most individuals, COVID-19 an infection will trigger delicate sickness nonetheless, it could make some individuals very unwell and, in some individuals, it may be deadly. Older individuals, and people with pre-existing medical situations (corresponding to heart problems, continual respiratory illness or diabetes) are in danger for extreme illness (See Protection measures for persons who are in or have recently visited (past 14 days) areas where COVID-19 is spreading).