As coronavirus continues to spread, a number of research on the nature of disease and its spread patterns are also taking place so that people can be better made aware about how the disease is spreading and how precautions can be taken to restrict its spread to minimum. Amidst all this, WHO is assessing ongoing research on the ways that COVID-19 is spread. Here's an analyses by Dr Maria Van Kerkhove, COVID-19 technical head on some of the COVID-19 queries that will help better understand the disease.
What are the main ways COVID-19 spread?
The majority of transmission that we know about is that people who have symptoms transmit the virus to other people through infectious droplets. But there are a subset of people who don't develop symptoms and to truly understand how many people don't have symptoms, there is actually no answer to that.
What does it mean to be asymtomatic or pre-symptomatic?
So when we say asymptomatic, we mean somebody that does not have symptoms, does not go on to develop symptoms. Truly no symtptoms. We know a number of them who are reported to be asymptomatic actually may have mild disease that they may go on to develop symptoms they may not quite register that 'I'm sick'. It like "I just feel a little bit unwell. I am just a little bit under the weather. I am a feeling a little bit fatigued."
And some of those individuals we would classify as pre-symptomatic, which means they have not yet developed symptoms.
Can I infect others if I have no symptoms?
We know from some of the viral shedding studies from some of the lab work that there are people who are infected with COVID-19 that can be PCR positive, that can test positive, one to three days before they develop symptoms and that something that we have know for quite some time now.
What we need to better understand and this is one the major unknows -- is what proportion is that is contributing to transmission.
How can asymptomatic people spread the virus?
When you sing or you're shouting in a nightclub because you can't hear your friend and you're saying you know can you hear me and you're close by and you're projecting your voice at someone then its clear that in that situation, if the virus is present in your upper respiratory mucosa, then there is every likelihood that you can project that virus.
What's the situation right know?
The last couple of days have been the highest number of daily cases in the world. So in terms of pandemic generation we are still very much on the up, on the upward climb on this mountain.
But what some countries have shown, many countries have shown is if you go at this in a very systematic way and you use a comprehensive approach that there is enough ''stopability'' in the virus.
We've seen that with the physical measures, social distancing, we have seen it with surveillance. And we have some choices to make as a society, because it is clear: If we can identify cases and their contacts and we ask those contacts to quarantine themselves and we support them in that quarantine that that can be a very successful way of both stopping the disease and avoiding large-scale lockdowns in the future.
