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Microsoft co-founder Bill Gates has a lot of experience with global public health issues through his work at the Bill & Melinda Gates Foundation. On Wednesday, Gates participated in an Ask Me Anything Q&A on Reddit, inviting questions about COVID-19 specifically or epidemics and pandemics more generally. Gates' foundation has committed up to $100 million to help with the global response to the virus, adding an additional $5 million for Gates' home state, Washington, which has been hit hard.

Testing woes

Gates noted that testing for the disease is still scattered and uneven.

"The testing in the US is not organized yet," he said. "In the next few weeks, I hope the government fixes this by having a website you can go to to find out about home testing and kiosks. Things are a bit confused on this right now. In Seattle, the U of W is providing thousands of tests per day but no one is connected to a national tracking system.

Some of Gates' responses could be viewed as encouraging. When asked how long the outbreak would last, Gates responded that while it would vary by country, there are ways to limit the length of time a nation would be affected.

Effective prevention

"China is seeing very few cases now because their testing and 'shut down' was very effective," he wrote. "If a country does a good job with testing and 'shut down,' then within 6-10 weeks they should see very few cases and be able to open back up."

How many will get it?

When asked about how much of the world's population might be affected, Gates worried about the effect on the poorest countries.

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"Taiwan, Hong Kong and Singapore acted quickly and will have very few cases," he said. "Even China will stay at a low level of their population (less than .01%) so far. Thailand is another exemplar. Unfortunately, in poorer countries, doing social distancing is much harder. People live in close proximity and need to work to get their food, so there could be countries where the virus will spread broadly."

When could a vaccine appear?

Gates also addressed the work on a vaccine. One reader asked if the commonly cited 18-month timeline for vaccine development could be sped up, and while Gates noted that this could happen, he outlined the difficulty of the work.

"There are over 6 different efforts going on to make a vaccine," Gates said. "Some use a new approach called RNA which is unproven. We will have to build lots of manufacturing for the different approaches knowing that some of them will not work. We will need literally billions of vaccines to protect the world."

He suggested that a form of treatment could come first. "A therapeutic could be available well before a vaccine," Gates said. "Ideally this would reduce the number of people who need intensive care including respirators."

Practical advice

One Reddit user asked Gates about precautions to take when delivering food and supplies to older relatives.

"Hand washing is key," Gates said. "Keeping a distance. Having someone else (deliver the items) if you have a fever or are coughing."

You can read Gates' entire Q&A online.